# Internships

Each year, CPPM welcomes more than a dozen trainees in the various research teams of the laboratory. The internships offered by the laboratory can be of several kinds:

• Bachelor's/Master's level physics internships: they are spontaneous or compulsory and are intended for Bachelor's and Master's level students who have completed a physics course. Specific offers are submitted by the various research teams during the year.

• Technical internships (BTS, IUT, Engineer): they are generally part of your school curriculum. Precise offers are submitted by the various teams and departments during the year.

• High school internships: we welcome high school students for observation internships for specific periods of time.

To apply for physics or technical internships, you must attach to your application a CV, a cover letter as well as your last transcript (transcript of the previous year or the last semester of the year current year if available ). For Master internships, recommendation letters from your professors or former internship supervisors may be requested.

Whatever the nature of your internship, a favourable response from one of our laboratory staff is not sufficient to hire you as an internship student. Indeed, only the agreement of the CPPM dirctor and the establishment of a legal agreement between the CPPM and your school/University are the two conditions to formaly welcome you as trainee student at CPPM.

Contacts: William Gillard (Physics Internships), Frédéric Hachon (Technical Internships), Jocelyne Munoz (Administrative Internships)

# Internship M2

Belle II
Search for tau lepton flavour violating decays with Belle II
Internship supervisor:
Justine Serrano - serrano@cppm.in2p3.fr
Description:

Being forbidden in the Standard Model (SM) of particle physics, lepton flavor violating decays are among the most powerful probes to search for physics beyond the SM.

In view of the recent anomalies seen by LHCb on tests of lepton flavor universality, the interest of tau lepton flavor violating decays has been greatly reinforced. In particular, several new physics models predict branching fractions of $$\tau\to\mu\mu\mu$$ and $$\tau\to\phi\mu$$ just below the current experimental limits.

The Belle II experiment located at KEK, Japan, has started physics data taking in 2019, aiming at collecting 50 times more data than its predecessor.

Thanks to its clean environment and high $$\tau^+\tau^-$$ cross section, it provides an ideal environment to study tau decays. The goal of this internship is to perform a sensitivity study of the $$\tau\to K^+K^-\mu$$ decay using the simulated data.

The analysis code is based on ROOT and python. Multivariate methods will be studied to optimize the analysis performances.

This internship could be followed by a PhD in the context of the NEPAL projet : https://www.cppm.in2p3.fr/Belle2/en/

Keywords:
Physique des particules
Code:
M2-2122-BE-01
HESS-CTA
Application of Convolutional Neural Network innovative reconstruction to real data of the Large-Sized Telescope of CTA
Internship supervisor:
Franca Cassol & Rubén Lopéz Coto - 0491827248 - cassol@cppm.in2p3.fr
Description:

The CTA (Cherenkov Telescope Array) is a worldwide project to construct the next generation ground based very high energy gamma ray instrument [1]-[2]. CTA will use tens of Imaging Air Cherenkov Telescopes (IACT) of three different sizes (mirror diameter of 4 m, 12 m and 23 m) deployed on two sites, one on each hemisphere (La Palma on the Canary Islands and Paranal in Chile). CTA will detect gamma-rays with energy ranging from 20 GeV up to 300 TeV by imaging the Cherenkov light emitted from the charge particle shower produced by the interaction of the primary gamma ray in the upper atmosphere.

The CTA unconventional capabilities will address some of the most intriguing questions of astroparticle physics such as the origin of very high energy galactic cosmic rays. The observatory completion is foreseen in 2025 but the first large size telescope (LST1) is already installed and taking data in La Palma. This telescope has a key role in the definition and validation of the methods and software tools for the future observatory.

This internship concerns the reconstruction of LST1 data by the use of innovative convolution neural network methods (CNN). Standard IACT event reconstruction is based on parametrization of the shower images and on machine learning algorithms trained with these parameters, for the estimation of the energy, the direction and the gammaness (the probability to be a gamma) of the primary particles [3]. Recently, several innovative reconstructions based on CNN have been developed in the context of CTA and of LST1 in particular [3]. Till now, these methods have been tested only on Monte Carlo simulated data. The goal of the internship is to verify their performance on data coming from real observations. The student will first make use of the newly proposed CNN methods to access their performance on simulated observations of the Crab Nebula (the standard candle of gamma-ray astronomy). Then, she/he will apply the same methods to Crab real data taken during the present LST1 commissioning phase.

The candidate needs a medium knowledge of the python programming language.

The internship will be in co-supervision with Dr. Rubén López Coto from the University of Padova (Italy). Candidates should send their CV and motivation letter as well as grades (Licence, M1 as well as their M2 if available) to cassol@cppm.in2p3.fr

A PhD contract can eventually follow the internship.

References:

[1] Science with the Cherenkov Telescope Array: https://arxiv.org/abs/1709.07997

[3] Lopéz-Coto, R. et al. Physics Performance of the Large-Sized Telescope prototype of the Cherenkov Telescope Array, Proceeding of 37th International Cosmic Ray Conference (ICRC 2021)

[4] Grespan, P. et al., Deep-learning-driven event reconstruction applied to simulated data from a single Large-Sized Telescope of CTA, Proceeding of 37th International Cosmic Ray Conference (ICRC 2021)

Keywords:
Astroparticules
Code:
M2-2122-CT-01
Preparatory study for the observation of the PeVatron candidate SNR G106.3-2 with the LST1+MAGIC Cherenkov telescopes
Internship supervisor:
Franca Cassol - 0491827248 - cassol@cppm.in2p3.fr
Description:

The CTA (Cherenkov Telescope Array) is a worldwide project to construct the next generation ground based very high energy gamma ray instrument [1]-[2]. CTA will use tens of Imaging Air Cherenkov Telescopes (IACT) of three different sizes (mirror diameter of 4 m, 12 m and 23 m) deployed on two sites, one on each hemisphere (La Palma on the Canary Islands and Paranal in Chile). The observatory will detect gamma-rays with energy ranging from 20 GeV up to 300 TeV by imaging the Cherenkov light emitted from the charge particle shower produced by the interaction of the primary gamma ray in the upper atmosphere.

The unconventional capabilities of CTA will address, among others, the intriguing question of the origin of the very high energy galactic cosmic rays by the search of galactic sources capable of accelerating cosmic rays up to the PeV, called PeVatrons. Recently, the Supernova Remnant (SNR) G106.3-2.7 has been indicated as a highly promising PeVatron candidate [4]. In fact, G106.3-2.7 emits gamma-rays up to 500 TeV from an extended region (~0.2o) well separated from the SNR pulsar and in spatial correlation with a molecular cloud.

The CTA observatory completion is foreseen in 2025 but the first large size telescope (LST1) is already installed and taking data in La Palma. LST1 is placed very close to the two MAGIC telescopes [3], which are one of the presently active IACT experiments. This configuration permits to perform joint observations of the same source with the three telescopes LST1+MAGIC. Joint acquisition not only increases the effective detection area but also improves the energy and angular resolution, thanks to the enhanced stereo data. While the LST1+MAGIC telescopes cannot reach enough sensitivity to access energies above 100 TeV, they can provide exclusive and unprecedented data for establishing the spectral morphology of this exiting PeVatron candidate in the 100 GeV-100 TeV energy range. A campaign of joint observations of G106.3-2.7 will start in 2022.

This internship concerns the setup of the reconstruction chain for G106.3-2.7 on the base of Monte Carlo data. In order to maximise the effective area at very high energy, G106.3-2.7 observation will be performed at large zenith angle (62o-70o), which is a challenging detection condition and asks to perform a preliminary verification of the detection performances. The student will first estimate the expected Instrument Response Function with the standard LST1 reconstruction [5], using the mono telescope approach. Then, s/he will estimate the performance of the MAGIC + LST1 stereo reconstruction with the joint reconstruction pipeline [6], presently under development. Eventually, the student will simulate the signal expected from the source with the two configurations.

The candidate needs a medium knowledge of the python programming language.

Candidates should send their CV and motivation letter as well as grades (Licence, M1 as well as their M2 if available) to cassol@cppm.in2p3.fr

A PhD contract can eventually follow the internship, it will be centred on the analysis of real data from G106.3-2.7, acquired in 2022 and the following years.

References:

[1] Science with the Cherenkov Telescope Array: https://arxiv.org/abs/1709.07997;

[3] MAGIC Collaboration, Aleksi?, J. et al. Astropart. Phys. 72 (2016) 7694.

[4] Z. Cao et al. Nature, 594, 3336 (2021); M. Amenomori et al. Nature Astronomy, 5, 460464 (2021)

Keywords:
Astroparticules
Code:
M2-2122-CT-03
Data analysis of the first Large-Sized Telescope of CTA for the search of high energy gamma-ray emission from the PeVatron candidate LHAASO J2108+5157
Internship supervisor:
Heide Costantini - 049182 72 57 - costantini@cppm.in2p3.fr
Description:

The origin of galactic cosmic rays is one of the main open questions in high energy astrophysics. PeVatrons are objects capable of accelerating particles up to the PeV (=10^{15} eV) energies and are therefore considered the galactic cosmic ray accelerators. The principal signature of PeVatrons is ultrahigh-energy (exceeding 100 TeV) gamma radiation. The search for PeVatrons has recently been boosted by the discovery of several ultrahigh energy gamma-ray sources by the Large High Altitude Air Shower Observatory (LHAASO) [1]. In particular no obvious counterpart has been found for the LHAASO J2108+5157 source at lower energies and its gamma-ray emission seems to be correlated with a giant molecular cloud favoring the hadronic origin [2]. Deeper observations of this source in the 0.1-10 TeV energy region are therefore important to establish its nature.

First observations have been performed on this source with the Large-Sized Telescope (LST1) deployed at La Palma on the Canary Islands. LST1 is the first telescope of the Cherenkov Telescope Array (CTA)[3][4] which is a worldwide project to construct the next generation ground based very-high-energy gamma-ray instrument.

The CPPM group has started since few years to work on the potentiality of CTA in detecting PeVatrons and is also working on the calibration and commissioning of the LST1.

The internship project will focus on the analysis of the first data taken with LST1 on the LHAASO J2108+5157 source. The goal will be to establish if LST1 can detect a high energy gamma emission coming from this source. The candidate will use the reconstruction chain (lstchain [5]) that has been developed for the single telescope and eventually extract significant spectral points in the case of a detection or establish upper limits in the case of no detection. The analysis tools that will be used during the internship are written in Python. The candidate should therefore have basic knowledge of Python programming.

This internship can be continued with a PhD thesis.

Candidates should send their CV and motivation letter as well as grades (Licence, M1 as well as their M2 if available) to costantini@cppm.in2p3.fr

References:

[1] Cao, Z., Aharonian, F.A., An, Q. et al. Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 ?-ray Galactic sources. Nature 594, 3336 (2021).

[2] Cao, Z., Aharonian, F.A., An, Q. et al. Discovery of the Ultra-high energy gamma-ray source LHAASO J2108+5157. https://arxiv.org/pdf/2106.09865.pdf

[4] Science with the Cherenkov Telescope Array: https://arxiv.org/abs/1709.07997

Keywords:
Astroparticules
Code:
M2-2122-CT-02
KM3NeT
Application of machine learning techniques to the analysis of data from the KM3NeT/ORCA deep sea neutrino detector.
Internship supervisor:
Paschal Coyle - 04918273 - coyle@cppm.in2p3.fr
Description:

KM3NeT/ORCA (Oscillation Research with Cosmics in the Abyss) is a deep sea

neutrino telescope currently under construction at a depth of 2500m in the

Mediterranean Sea off the coast of Toulon. ORCA is optimised for the detection of

low energy (3-100 GeV) atmospheric neutrinos and will allow precision studies

of neutrino oscillation properties. ORCA is part of the multi-site KM3NeT research infrastructure, which also incorporates a second telescope array (in Sicily) optimised for the detection of high-energy cosmic neutrinos.

The first ORCA detection strings have been operating for more than a year and are providing high quality data. During this stage the student will apply machine learning techniques to the data analysis with the aim to improve the angular and energy resolutions of the current event reconstruction algorithms. It is expected the candidate will follow this stage with a PhD on measuring the neutrino oscillation parameters.

http://www.cppm.in2p3.fr/rubrique.php3?id_rubrique=259

Keywords:
Astroparticules
Code:
M2-2122-KM-01
Machine Learning Assisted Neutrino Flavour Tagging
Internship supervisor:
Sorry, this position is no longer available
Description:

The Neutrino Team at CPPM is strongly involved in the KM3NeT/ORCA neutrino telescope, under construction in the abyss (-2500m) of the Mediterranean sea, 40km offshore Toulon. The first detection units that have been deployed are successfully collecting data. The detector is now large enough to access yet unexplored physics territories. A very exciting topic is the search for tau neutrinos appearing in the neutrino flux created in the collisions of cosmic rays in the atmosphere. The appearance probability is poorly known and KM3NeT/ORCA has a unique potential to measure it. Such measurements could lead to a major discovery regarding the existence of sterile neutrinos.

One of the keystones for these studies is the tag of the neutrino flavours (electron, muon, or tau); hence, in this project, the student will develop Machine Learning algorithms to perform this kind of identifications. The expected skills are to master the basics of neutrino oscillation and to program in python, c++, ROOT.

Keywords:
Astroparticules
Code:
M2-2122-KM-03
Implementation of a neutrino selection module based on machine learning tools for the KM3NeT online analyses
Internship supervisor:
Damien Dornic / Feifei Huang - 0491827682 - dornic@cppm.in2p3.fr , feifei.huang@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Doing neutrino astronomy is a long dream in astroparticle physics. IceCube and ANTARES have found the first evidences of a few neutrino sources, mainly related to blazars (active galactic nuclei with their jets posting toward the Earth) and tidal disruption events. For most of those explosive events can release enormous amounts of energy both in electromagnetic radiation and in non-electromagnetic forms such as neutrinos and gravitational waves. This is at the basis of multi-messenger astronomy. KM3NeT, the second generation neutrino detectors in the Mediterranean Sea, will have significant better performances, either in term of effective area or in term of angular resolution.

In CPPM, we are mainly working on the development of multi-messenger analyses with high-energy neutrinos detected with ANTARES and KM3NeT neutrino telescopes. In this context, we are developing a real-time analysis framework that is able to send neutrino alerts and to receive and process a cross-match analysis with high-energy neutrinos in coincidence with selected potential external triggers.

During this intern ship, the student will implement a neutrino selection module that takes in inputs the reconstructed and classified neutrino streams. To reach a sustainable false alert rate (1-2 per month), It will be necessary to filter on the topology of the events, the multiplicity, the energy and the estimate of the reconstruction error. The student will have to implement such module based on machine learning tool.

The analyses will be performed using C++ or python.

Keywords:
Astroparticules
Code:
M2-2122-KM-02
Renoir
Constraining dark energy parameters or probing new cosmology with supernova dataset
Internship supervisor:
Dominique Fouchez - 04 91 82 76 49 - fouchez@cppm.in2p3.fr
Description:

Twenty years after the discovery of the current acceleration of the expansion of the universe by supernova measurements, the supernova probe remains the most accurate way to measure the parameters of this recent period in the history of our universe dominated by the so-called dark energy.

The precision measurements that can be performed by the supenova probe will be a crucial element that, in combination with other probes (LSS, weak lenses, CMB, etc.), will put strong constraints on the nature of dark energy. This will be made possible by the exceptional Supernova data set to be provided by LSST, with a combination of huge statistics and extreme calibration accuracy.

The Rubin observatory with the Large Survey of Space and Time (Rubin/LSST) project will be commissioned in 2022 and will run at full speed by the end of 2023. It is an 8.4-metre telescope with a 3.2 billion pixel camera, the most powerful ever built.

This telescope will take a picture of half the sky every three nights for ten years. This survey will make it possible to measure billions of galaxies with great accuracy and to track the variation over time of all transient objects. With many other astrophysical studies, it will be a very powerful machine for determining cosmological parameters using many different probes and, in particular, it will impose strong constraints on the nature of dark energy. The LSST project aims to discover up to half a million supernovae. This two to three orders of magnitude improvement in statistics over the current data set will allow accurate testing of dark energy parameters and will also impose new constraints on the universe's isotropy.

In this Master 2 internship we propose to prepare the first analysis of LSST supernova data by performing an analysis using LSST software and our deep learning method for identifying supernova on existing HSC/Subsaru data. Indeed, the HSC data has characteristics that are very close to what we expect with Rubin/LSST. The CPPM LSST group is already engaged in precision photometry work for LSST with direct involvement in algorithm validation within DESC/LSST [1][2][3] and has proposed a new deep learning method to improve the photometric identification of supernovae [4] and photometric redshifts [5].

Keywords:
Cosmologie observationnelle
Code:
M2-2122-RE-01
Testing dark energy with the integrated Sachs-Wolfe effect in the Euclid space mission
Internship supervisor:
Description:

Observations of our universe on a large scale by different cosmic probes tend to agree for a model of a relatively flat universe whose matter is mostly in the form of dark matter and which is recently dominated by dark energy causing the acceleration of its expansion. The European space mission Euclid (Laureijs et al. (2011)), scheduled for launch in 2023, will collect the spectroscopic position of more than 35 million galaxies and the photometric image of about 1.5 billion galaxies. Euclid will observe for about 6 years and will cover an area of about 15,000 deg2. Euclid's observations will allow through the analysis of the position of galaxies and their deformation by gravitational lensing effect to estimate the cosmological parameters describing our universe with an unprecedented accuracy. Cosmic voids are defined as large (a few tens of Mpc/h) spaces of low density surrounded by galaxies (grouped in clusters and filaments) in the cosmic web. These objects have recently aroused interest because of their low density nature making them good candidates for testing gravity. Nevertheless, unlike galaxy clusters characterized as virialized groupings of galaxies, the notion of cosmic void can be defined in different ways and one finds nowadays in the literature various algorithms using different methodologies to identify them (see for example Colberg et al. (2008) for a comparison).

On the other hand, the cosmic microwave background (CMB), electromagnetic radiation coming from the primordial universe, is a cosmic probe rich in information and the statistical study of the CMB temperature maps will have allowed to constrain the cosmological parameters to unprecedented degrees (Planck Collaboration et al. (2020)). This radiation coming from the background of the universe will cross, and be affected by different processes, the field of matter that we observe with galaxy probes. Therefore, there are correlations between the cosmic radiation observed today and the position of large structures observed by a satellite like Euclid. Combining cosmological probes from different types of observations has recently been shown to be an excellent tool for increasing the accuracy of our measurements (Baxter et al. (2019); Abbott et al. (2019)). Similarly to high-density areas the footprint of low-density areas can be detected in the CMB maps. Not only by their graviational de-lensing effect but also by their integrated Sachs-Wolfe signal (ISW, Sachs & Wolfe (1967)). Indeed, the ISW signal is defined as a dynamical property of dark energy causing the decay of large-scale gravitational potentials that impart small anisotropies to the primary fluctuations of the CMB radiation. Interestingly, the ISW signal from cosmic voids has already been measured in different ways on data from different observations and in cosmological simulations and some measurements have claimed disagreement with the standard model of cosmology at a level of about 3? (see e.g. Kovacs et al. (2021)).

In this context, this internship, addressed to a Master 2 student, will consist in developing a methodology for the identification and optimal treatment of cosmic voids

in order to maximize the correlation signal of these voids with the integrated Sachs-Wolfe signal maps of the CMB. The selected student should have knowledge of programming languages (especially Python). This

internship will lead to a thesis, partly financed by the CNES, in the Renoir group of the CPPM.

Références

Abbott T. M. C., et al., 2019, , 100, 023541

Baxter E. J., et al., 2019, , 99, 023508

Colberg J. M., et al., 2008, , 387, 933

Kov ?acs A., Beck R., Smith A., R ?acz G., Csabai I., Szapudi I., 2021, arXiv

e-prints, p. arXiv:2107.13038

Laureijs R., et al., 2011, arXiv e-prints, p. arXiv:1110.3193

Planck Collaboration et al., 2020, , 641, A6

Sachs R. K., Wolfe A. M., 1967, in Liege International Astrophysical Colloquia.

Keywords:
----
Code:
M2-2122-RE-03
Caracterization of the spectral response of the NISP instrument
Internship supervisor:
William GILLARD - gillard@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Euclid is an M-class space mission from ESA's Cosmic Vision program that was selected in 2011 by ESA for a scheduled launch in 2023. The Euclid mission is designed to map the observable Universe in order to understand the origins and the nature of the acceleration of the expansion of the Universe discovered in 1998. The Euclid mission is therefor optimized to study the nature of dark energy, dark matter and gravity from the measurements of two independent cosmological probes: the cosmic shear through measurements of gravitational shear of low amplitude and through the measurements of the matter power spectrum traced by the spatial distribution of galaxies. These measurements are carried out by two independent instruments: a visible imager (VIS) optimized for measurements of the weak gravitational lensing and a spectrophotometer working in the near infrared (NISP) dedicated to measurements of the redshift of galaxies. One of the advantages of the NISP is to make slitless spectroscopy which allows it to measure the redshift of a thousand galaxies on a single field of an angular size comparable to the apparent angular size of the moon. The disadvantage of slitless spectroscopy is that it induces contamination of the spectra (contamination between neighboring sources as well as self-contamination of the extended source) and a good knowledge of the instrument is necessary to obtain an optimal extraction of the observed spectra.

To achieve this optimal extraction and achieve the scientific goal, spectroscopic calibration of the NISP is an important step of the data reduction. In addition, it should noted that the accuracy of the instrumental response strongly affects the accuracy and bias of scientific results. To answer this problem, the NISP instrument was tested on the ground in 2019 and 2020 to obtain a series of measurements dedicated to the evaluation of its performances and to its calibration. A large part of these tests were under the responsibility of the Instrument Scientist of the NISP, member of our team and supervisor of this internship, former responsible for the spectroscopic calibration of the NISP.

The internship work will therefore consist of analyzing all the data collected by the NISP instrument during the various ground test campaigns in order to build a model of the spectral response of the instrument, in its spectroscopic channels

This internship is aimed at M1 or M2 physics students with solid knowledge of optics and showing a strong interest in instrumentation and data analysis. Mastery of python and C ++ programming languages ??is strongly recommended. To apply, you must send the internship manager a CV, a cover letter and your last transcript (the transcript of the first semester of the current year if you have it). Letters of recommendation from your previous internship supervisor or teachers will also be asked if your application is accepted.

Any incomplete application will not be studied.

Keywords:
Instrumentation
Code:
M2-2122-RE-02
imXgam
Deep learning labelling of Cherenkov and scintillation photons in a crystal following the photoelectric interaction of an annihilation photon
Internship supervisor:
Christian Morel - 04.91.82.76.73 - morel@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Context

The imXgam research team conducts interdisciplinary research activities for imaging applications of ionising radiation in the field of health and energy. The internship topic proposed here aims at improving the temporal performance of gamma ray detectors in the context of time-of-flight positron emission tomography (PET).

The coincidence time resolution (CTR) of state-of-the-art clinical TOF-PET cameras is around 210 ps FWHM. A CTR of 10 ps FWHM would allow the position of an electron-positron annihilation to be located at better than 1.5 mm FWHM, making it possible to obtain a PET image virtually without tomographic inversion [1]. One possible way to improve the temporal performance of detectors is to exploit the Cherenkov radiation generated by the motion of photoelectrons in a transparent interaction medium [2]. If this transparent medium is also scintillating, then two types of visible light photons are emitted with temporal distributions different from each other, the first almost simultaneously by the Cherenkov effect and the second slightly delayed by de-excitation of a radiative centre causing the scintillation phenomenon [3]. The photons are then likely to undergo reflections from the faces of the transparent medium before being collected by a photodetector(s) in order to accurately label the photoelectric interaction with a detection time. The existence of different temporal distributions makes the measurement of CTR complex [4].

Aim of the internship

The aim of the internship is to determine whether deep learning techniques can be used to label these two populations of visible light photons given their time and location of detection and, if so, to accurately date the photoelectric interaction in order to improve the temporal resolution of the coincidence. The trainee will build Monte Carlo datasets using GATE [5] to simulate the interaction of 511 keV gamma rays in a scintillating medium and exploit Monte Carlo truth to learn the position of the photoelectric interaction, the type of emission (Cherenkov or scintillation) and the time of the interaction, and then seek to reduce the dimension of the phase space as much as possible while preserving the accuracy of the observables retrieved by deep learning.

Required knowledge: Python programming, knowledge of radiation-matter interactions, notions of deep learning (DL)

[1] P. Lecoq, C. Morel et al. Roadmap towards the 10 ps time-of-flight PET challenge, Phys. Med. Biol. 65 (2020) 21RM01

[2] S.K. Kwon et al, Ultrafast timing enables reconstruction-free positron emission imaging, Nat. Photon. (2021) https://doi.org/10.1038/s41566-021-00871-2

[3] D. Yvon et al, Design study of a scintronic crystal targeting tens of picoseconds time resolution for gamma ray imaging: the ClearMind detector, J. Instrum. 15 (2020) P07029

[4] J. Nuyts et al. Estimating the relative SNR of individual TOF-PET events for Gaussian and non-Gaussian TOF-kernels, in Proc. Fully-3D'2021, G. Schramm, A. Rezaei, K. Thielemans and J. Nuyts eds, pp. 19-23.

Keywords:
Imagerie médicale
Code:
M2-2122-IM-01
Development and evaluation of an automatic deep learning segmentation method for an in vivo study on cellular hepatocarcinoma
Internship supervisor:
Yannick Boursier - 04 91 82 76 41 - boursier@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

The imXgam research team conducts interdisciplinary research activities for imaging applications of ionising radiation in the field of health and energy. The internship topic proposed here aims at improving the performance of an automatic segmentation process of liver tumours in the context of small animal CT.

Context

This internship is part of the DePIcT project financed by the Mission pour les Initiatives Transverses et Interdisciplinaires of the CNRS (https://miti.cnrs.fr/projet-multi-quipe/depict/ , https://www.in2p3.cnrs.fr/fr/cnrsinfo/palmares-des-80prime-2020-4-projets-pilotes-par-lin2p3-decrochent-un-financement). As part of a preclinical study on hepatocellular carcinoma, longitudinal in vivo follow-ups are carried out using the PIXSCAN-FLI, a photon counting micro-CT developed at the CPPM. It has been demonstrated that photon counting guarantees very high contrast on the 3D images.

In addition, the ultra-fast acquisition (100 images per second) allows the capture of the respiratory movements of the mouse. This study is based on an imaging protocol established at the CPPM (Cassol et al. 2019), which consists in labelling the liver with Barium nanoparticles, a contrast agent absorbed by liver macrophages. Tumours appearing in negative can then be observed and characterized due to the radiopacity of the contrast agent surrounding the tumours. This technique allows the differentiation of liver from tumours and the estimation of a series of important tumour parameters over time (size, shape, etc.)

Objectives

The aim of the internship is to implement and evaluate the performance of a state-of-the-art Deep Learning method in micro-CT for automatic segmentation (Léger et al. 2018, Brion et al. 2020). The aim here is to automatically segment the liver as well as liver tumours. The trainee will be able to rely on a large real-world database for which tumour segmentation by an expert is already available. If these methods prove satisfactory, they will be incorporated into the PIXSCAN-FLI automatic data processing pipeline for routine use.

This study may include analysis and correction of mouse breathing movements to improve the sharpness of 3D images.

Skills required: Python programming, deep learning. Knowledge of the context and physics of CT imaging will be appreciated.

Bibliography

E. Brion et al, Domain adversarial networks and intensity-based data augmentation for male pelvic organ segmentation in cone beam CT in Computers in Biology and Medicine https://dial.uclouvain.be/pr/boreal/object/boreal:245104

J. Léger et al, Contour Propagation in CT Scans with Convolutional Neural Networks in Advanced Concepts for Intelligent Vision Systems https://dial.uclouvain.be/pr/boreal/object/boreal:203221

F. Cassol et al, Tracking dynamics of spontaneous tumours in mice using Photon Counting Computed Tomography, iScience 21 (2019) 68-83 https://www.sciencedirect.com/science/article/pii/S2589004219303943

Keywords:
Imagerie médicale
Code:
M2-2122-IM-03

# Internship M1

Atlas
Development or Machine Learning Algorithms for ATLAS Data Acquisition
Internship supervisor:
Lauri Laatu - 0491827640 - laatu@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Our group is developing machine learning for embedded trigger systems for the ATLAS detector, and as such the developed neural networks need to be optimized for speed and resource consumption on Field Programmable Gate Arrays (FPGAs). The networks are developed using Tensorflow/Keras which is a Python library, but historically C++ has been the language used in particle physics for its speed. While Python has a reputation as a slow language, that is not anymore the case with new methods such as Numba that uses LLVM and Just In Time (JIT) compilation to optimize the performance. The purpose of this internship is to develop methods for fast data processing with Python that would replace and complement the existing parts written in C++ or (slow) Python. This work consists of writing and evaluating Numba as a method to speed up Python used in the data processing and analysis as well as possibility to merge Python with C++, such as pybind11. This internship would also consist of developing neural networks with tools suitable to create more optimized networks that would retain their original accuracy, but be compressed to run fast and consume low resources when running on FPGAs.

The project is done in English. The candidate is expected to have knowledge in Python programming and good communication skills in English. The project length is expected to be 2 to 3 months and can start in spring 2022.

Keywords:
Informatique
Code:
M1-2122-AT-01
b-quark identification with the ATLAS detector at HL-LHC
Internship supervisor:
Thomas Strebler - +33 4 91 82 72 52 - strebler@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

The Higgs boson was discovered in July 2012 by the ATLAS (http://atlas.cern) and CMS collaborations at the LHC, and led to a Nobel Prize for F. Englert and P. Higgs in 2013. Since then and till 2019, the LHC experiments have collected a lot of new data, in order to better characterize the Higgs boson and to possibly find evidences of new physics beyond the Standard Model. However, in order to increase by a factor 100 the amount of useful data we already have, the LHC and its detectors will be upgraded for the High-Luminosity phase of LHC (2025-2035). The ATLAS group at CPPM, building on its previous expertise, is developing new sub detectors and reconstruction algorithms.

The ATLAS detector upgrade will be the opportunity to install a new High-Granularity Timing Detector (HGTD), aimed at providing additional timing measurements associated with reconstructed tracks in the forward region of the detector. This additional information can provide new handles to identify charged particles produced in different proton collisions in a given bunch-crossing (pile-up) and mitigate their influence on reconstruction and identification algorithms focused on particles produced in the hard-scatter interaction. b-tagging algorithms, used to identify jets of particles stemming from the hadronization of bottom quarks, rely on particular on the reconstruction of displaced secondary vertices, which can be quite sensitive to the presence of pile-up particles in the forward region of the detector.

The student will use detailed Monte-Carlo simulations to explore the potential improvement in b-tagging performance associated with the pile-up rejection capabilities offered with the HGTD detector. The project provides an opportunity for the student to get an exposure to a broad spectrum of topics: LHC physics notably the Higgs sector; basics of silicon detectors and track-finding; b-tagging algorithms. The project requires the use of the ROOT (http://root.cern.ch) analysis framework and the writing of C++ code: their prior knowledge is desirable but not mandatory.

Keywords:
Physique des particules
Code:
M1-2122-AT-02
Communication
Development of a digital application to present CPPM activities to a high school audience.
Internship supervisor:
Magali Damoiseaux - 04.91.82.72.28 - damoiseaux@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

The CPPM is developing an application to present the laboratory's activities to a high school audience. The digital communication assistant trainee will be part of the project team and will contribute to the production of multimedia contents, with several components: an editorial section on fundamental topics, video interviews presenting the jobs and skills, knowledge learning tests. The duration of the internship is 3 months.

Keywords:
Physique des particules
Code:
M1-2122-CO-01
HESS-CTA
Multi-wavelength studies of galactic binary systems
Internship supervisor:
S Le Stum / JP Ernenwein - ernenwein@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Le groupe HESS au CPPM travaille sur l'étude multi-longueur d'onde de systèmes binaires galactiques, avec pour but la recherche d'une éventuelle émission de photons gamma de très haute énergie (>100GeV), dans le cadre des observations de l'expérience HESS (voir https://www.mpi-hd.mpg.de/hfm/HESS ).

Plus spécifiquement, nous nous intéressons aux Microquasars, constitués d'un objet compact (trou noir ou étoile à neutron) accrétant la matière d'une étoile compagnon, systèmes caractérisés par des jets (voir par exemple https://arxiv.org/abs/1607.04613 et https://arxiv.org/abs/1908.06958 ).

Nous nous intéressons également aux spiders binaries (black-widows: veuves noires, et redbacks: veuves noires à dos rouge) : ces noms sont donnés à des systèmes pulsars non accrétants + étoile compagnon dans lesquels l'étoile à neutrons interagit avec son compagnon par son vent intense de particules relativistes et de rayonnement. Un choc intra-binaire peut se former et constituer le site d'accélération de particules, siège d'une émission non thermique. Nous collaborons en particulier avec les auteurs de cet article: https://arxiv.org/abs/2010.01125 ( voir aussi https://arxiv.org/abs/2108.01705 ).

Le travail à faire concerne prioritairement les spider binaries, mais pourra être rediscuté au moment du stage, selon les besoins du groupe et les affinités du stagiaire. Il consiste à réunir et analyser les informations d'observatoires de rayons X (satellites), de photons gamma de haute énergie (satellite FERMI), qui sont publiques, pour déterminer les périodes potentiellement plus propices à l'émission de photons gamma de très haute énergie (>100GeV) selon le modèles de nos collaborateurs, afin d'exploiter les données HESS déjà acquises et qui seraient concomitantes.

Keywords:
Astroparticules
Code:
M1-2122-CT-01
KM3NeT
Development of a neutrino filter in the FINK broker
Internship supervisor:
Damien Dornic - 0491827682 - dornic@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Time-domain astronomy has received a considerable boost in recent years due to its ability to study extreme physics, to track cataclysmic phenomena like the birth of stellar mass black holes or the mergers of neutron stars, to probe distant

regions of the Universe, and to identify candidate sources for multi-messenger astrophysics. These explosive events can release enormous amounts of energy both in electromagnetic radiation and in non-electromagnetic forms such as neutrinos

and gravitational waves. They lie at the frontier of our understanding of the laws of physics under the most extreme conditions. Multi-messenger astronomy  the observation of astrophysical objects and processes using combinations of different messengers such as electromagnetic radiation, neutrinos, cosmic rays and gravitational waves  has emerged as a major new field in astronomy during the last years.

In CPPM, we are mainly working on the development of multi-messenger analyses with high-energy neutrinos detected with ANTARES and KM3NeT neutrino telescopes. In this context, we are developing a real-time analysis framework that is able to send neutrino alerts and to receive and process a cross-match analysis with high-energy neutrinos. In the next years, the LSST telescope in Chile will be one of the major discover of optical transients. Around a million triggers are expected each night. To account for these large numbers, LSST is developing some brokers to filter the alerts. In France, some colleagues are implementing the FINK broker (https://arxiv.org/abs/2009.10185). Some actual data are available with the ZTF telescope in US.

During this intern ship, the student will implement a filter chain in the broker to identify the most interesting candidates for the neutrino searches. It will filter on the nature of the transient, the number of detections, the light-curve and some cross-matches with astrophysical catalogues.

The analyses will be performed using C++ or python.

Keywords:
Astroparticules
Code:
M1-2021-KM-01
Studies of neutrino oscillations with the KM3NeT/ORCA detector
Internship supervisor:
Chiara Lastoria - lastoria@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

The KM3NeT experiment is a next-generation neutrino telescope, currently under construction in the two sites: ORCA (Oscillation Research with Cosmics in the Abyss) and ARCA (Astroparticle Research with Cosmics in the Abyss).

The ORCA site foresees the installation of 115 detection units (DUs), at 2500m depth in the Mediterranean Sea off Toulon and it is optimized for the atmospheric neutrino detection in the 3-100 GeV energy range, allowing for precision studies of neutrino oscillation parameters. Currently, only partially instrumented, KM3NeT/ORCA has already been operating for several months and it is collecting high-quality data. During this internship, the student will have the opportunity to become familiar with neutrino physics and analyze the KM3NeT/ORCA data collected so far, for studying neutrino oscillation properties. It is expected that the candidate will pursue similar studies in an M2 internship and eventually a Ph.D. in our group.

Keywords:
Astroparticules
Code:
M1-2122-KM-01
Renoir
Caracterization of the spectral response of the NISP instrument
Internship supervisor:
William Gillard - gillard@cppm.in2p3.fr
Description:

Euclid is an M-class space mission from ESA's Cosmic Vision program that was selected in 2011 by ESA for a scheduled launch in 2023. The Euclid mission is designed to map the observable Universe in order to understand the origins and the nature of the acceleration of the expansion of the Universe discovered in 1998. The Euclid mission is therefor optimized to study the nature of dark energy, dark matter and gravity from the measurements of two independent cosmological probes: the cosmic shear through measurements of gravitational shear of low amplitude and through the measurements of the matter power spectrum traced by the spatial distribution of galaxies. These measurements are carried out by two independent instruments: a visible imager (VIS) optimized for measurements of the weak gravitational lensing and a spectrophotometer working in the near infrared (NISP) dedicated to measurements of the redshift of galaxies. One of the advantages of the NISP is to make slitless spectroscopy which allows it to measure the redshift of a thousand galaxies on a single field of an angular size comparable to the apparent angular size of the moon. The disadvantage of slitless spectroscopy is that it induces contamination of the spectra (contamination between neighboring sources as well as self-contamination of the extended source) and a good knowledge of the instrument is necessary to obtain an optimal extraction of the observed spectra.

To achieve this optimal extraction and achieve the scientific goal, spectroscopic calibration of the NISP is an important step of the data reduction. In addition, it should noted that the accuracy of the instrumental response strongly affects the accuracy and bias of scientific results. To answer this problem, the NISP instrument was tested on the ground in 2019 and 2020 to obtain a series of measurements dedicated to the evaluation of its performances and to its calibration. A large part of these tests were under the responsibility of the Instrument Scientist of the NISP, member of our team and supervisor of this internship, former responsible for the spectroscopic calibration of the NISP.

The internship work will therefore consist of analyzing all the data collected by the NISP instrument during the various ground test campaigns in order to build a model of the spectral response of the instrument, in its spectroscopic channels

This internship is aimed at M1 or M2 physics students with solid knowledge of optics and showing a strong interest in instrumentation and data analysis. Mastery of python and C ++ programming languages ??is strongly recommended. To apply, you must send the internship manager a CV, a cover letter and your last transcript (the transcript of the first semester of the current year if you have it). Letters of recommendation from your previous internship supervisor or teachers will also be asked if your application is accepted.

Any incomplete application will not be studied.

Keywords:
Instrumentation
Code:
M1-2122-RE-01

# Technical Internship

DarkSide
DarkSide calibration mockup
Internship supervisor:
Wingerter-Seez - 7267 - wingerter-seez@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

During six weeks (from 1st June until 15th of July), the student in engineering will participate to the tests of the DarkSide calibration mock-up: measurements at cold (LN2), CAD description of the mock-up.

Keywords:
Instrumentation
Code:
Ingenieur-2122-DS-01
Electronique
Conception de building block en technologie CMOS adapté au détecteur pixellisé de BelleII
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Description:

BelleII est un détecteur polyvalent du collisionneur SuperKEKB au Japon.

Il a été conçu et construit pour étudier la physique au-delà du Modèle Standard, pour tester de nouveaux modèles de physique et rechercher les signatures de nouvelles particules.

Le détecteur BelleII est un détecteur de particules qui mesure 7,5 m de long, 7 m de haut. Il est composé principalement d'un détecteur de Vertex et d'un calorimètre. En augmentant la luminosité de l'accélérateur de particule

SuperKEKB, le sous-ensemble Vertex de BelleII doit être mis à jour d'ici 2026.

Une collaboration internationale s'est ainsi structurée afin de réfléchir et concevoir cette jouvence du détecteur.

Au CPPM, un groupe d'une dizaine de physiciens, ingénieurs et techniciens est

impliqué dans le projet BelleII et s'intéresse en particulier à l'évolution du détecteur de vertex (VXD), détecteur interne le plus proche du point d'interaction. Ce détecteur de traces(trajectographe) est destiné à suivre le passage des particules dès leur formation.

La brique élémentaire du trajectographe est un circuit intégré spécifique (ASIC) matriciel de plusieurs millions de transistors.

Ce circuit opère comme un appareil photo à pixels, qui doit prendre une image de la détection des particules. Plusieurs contraintes de conception sont imposées sur l'électronique, comme la surface,la rapidité, la consommation et la précision. De plus, afin de fonctionner en toute autonomie, le circuit a besoin de fonctions générales, comme un « bandgap reference », un capteur de

température, un buffer analogique et son ADC, des circuits numériques de décisions et mémoires,ou encore un système de distribution des alimentations ou polarisations des étages. Des étages d'entrée/ sortie à hautes vitesses comme les standards LVDS ou CML seront aussi intégrés.

Activité principale :

Dans un premier temps, le/la stagiaire doit mener une recherche bibliographique détaillée sur le circuit servant de référence au projet (TJ-MONOPIX2) ainsi que sur les détecteurs à pixels monolithiques et sur les fonctions générales. Ensuite, il lui sera proposé d'étudier et concevoir une des fonctions qui soit le mieux adaptée à l'application selon le cahier des charges fourni.

En fonction de l'avancement du projet, le/la stagiaire aidera l'équipe de conception à finaliser le circuit prototype OBELIX, pour une fabrication courant 2022.

- Etude bibliographique sur les architectures de la fonction.

- Dessin des masques (Layout)

- Simulation post-layout

- Des tests sur d'anciens circuits sont à prévoir.

Connaissances requises :

- Bonnes connaissances en conception de circuits intégrés en technologie CMOS

- Connaissance dans la manipulation d'instruments de mesure

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-01 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Electronique
Code:
Ingenieur-2122-EL-01
Bancs de test et de caractérisation de circuits intégrés pour les futurs collisionneurs de particules
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Description:

Le Centre de Physique des Particules de Marseille (CPPM) participe à plusieurs projets visant à développer des circuits intégrés monolithiques pour les futurs collisionneurs de particules. Notre groupe travaille en collaboration avec plusieurs partenaires, en particulier le CERN (« Centre Européen pour la Recherche Nucléaire ») ainsi que l'Université de Bonn, le CEA et d'autres laboratoires CNRS. Cette activité est présente au CPPM depuis près de 10 ans et est proche d'aboutir à une utilisation au sein d'un futur détecteur.

En 2021, avec nos partenaires, 3 circuits intégrés différents ont été fabriqués. Leur caractérisation doit être finaliser en 2022. Les deux premiers circuits, baptisés TJ_MONOPIX2' et LF_MONOPIX2', sont conçus en technologie TJ 180 nm et LF 180 nm respectivement. La particularité de ces circuits est d'être constitué d'une matrice de pixels et d'une électronique Front End effectuant la mise en forme de signaux et leur discrimination. Leur association permet de détecter les particules qui traversent le circuit. Un troisième circuit est conçu en technologie innovante (TJ 65 nm) et contient un ensemble d'oscillateurs en anneau formé de cellules numériques standards. La mesure de la fréquence d'oscillation permet de caractériser les performances de ces cellules en fonction de plusieurs paramètres : la température, les conditions de polarisation et la dose en irradiation.

Activité principale :

Le/la stagiaire a pour mission de contribuer au développement des bancs de tests et de caractérisation des circuits.

Un banc est constitué de manière générale de :

- Un circuit intégré (ASIC) monté sur une carte fille

- Une carte mère qui intègre un FPGA et un micro-processeur

- Un PC contrôlant les cartes et instruments de mesures (alimentation,

multimètres, etc..)

Un programme en Python ou C++ pilote le microprocesseur qui gère les alimentations sur la carte mère, ainsi que le « slow control ». Ensuite, un firmware en VHDL est développé pour le FPGA qui commande l'ASIC en temps réel et récupère les résultats de la mesure. Les données sont stockées sur le PC et traitées par un software en Python ou autre. LabView peut être envisagé pour piloter des appareils de mesures.

Le stage comportera :

- La lecture de la documentation et la prise en main du banc de test,

- Développement du banc de test (automatisation de certains tests par exemple)

- Tests de différents circuits intégrés

- Traitement de données et interprétation des résultats

- Présentations des résultats en réunion de groupe

Connaissances requises :

- Bonnes connaissances en électronique générale

- Développements de programmes en langage Python, C++, LabView

- Bonnes connaissances en design FPGA en langage VHDL et avec Quartus

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-03 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Physique des particules
Code:
Ingenieur-2122-EL-03
Participation aux développements d'une carte d'acquisition de données rapides avec FPGA
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Description:

Le Centre de Physique des Particules de Marseille, unité mixte de recherche CNRS/Aix-Marseille Université vient de construire et de livrer au CERN le système d'acquisition des données de l'expérience LHCb : lecture de l'ensemble des données (30 Terabits/s) des sous-détecteurs via 10000 liens optiques à 10 Gbits/s, traitement en temps réel puis envoi vers une ferme de calcul constituée de plusieurs milliers de processeurs. Le CPPM s'intéresse désormais à la prochaine génération qui devra avoir une puissance de calcul 10 fois supérieure au système actuel. Le FPGA le plus récent d'Intel (AgileX, 2.7 million de logic cells) et des liens sériels à 112 Gbits/s seront utilisés

Activité principale :

Il s'agit de participer aux développements de la carte prototype du futur système. La mission proposée sera définie avec le/la candidat(e), selon ses goûts et ses connaissances . Il s'agira de participer aux développements de la carte prototype du futur système, soit en conception hardware, soit en développant des firmwares et softwares qui permettront de tester le premier prototype de la carte :

- Intégrité de signal et simulations de liaisons à 58 Gbits/s PAM4

- Monitoring automatique de la carte (courants, tension, température)

- Étude thermique et simulation du refroidissement de la carte

- Conception hardware (distribution d'horloge précise, drivers optiques ..)

- Firmware d'interfaçage périphériques (PLLs,senseurs,interfaces optiques)

- Interfaçage de la carte au bus PCI Express Gen5

- Logiciel en Python de programmation des circuits périphériques du FPGA

- Monitoring en temps réel de la qualité des liens sériels (eye diagram)

Le ou la stagiaire sera accueilli(e) au sein du service électronique du CPPM qui possède un savoir-faire étendu dans la programmation des FPGA et en conception de cartes à très haute densité.

Le travail s'effectuera dans un environnement de recherche international.,quelques déplacements au CERN (Genève) seront possibles en vue d'assister à des réunions de collaboration.

Connaissances appréciées :

Les connaissances suivantes seront appréciées pour travailler sur les différents sujets du stage :

- Électronique analogique et numérique

- Conception de firmware FPGA en langage VHDL

- Conception logicielle, langage Python et éventuellement PyQt

- Appareils de mesure~: Serial Data analyser, TDR, analyseur de spectre~

- Simulations électriques et thermiques (alimentations de FPGA)

- Intégrité de signal,transmission de signaux rapides, liaison série à haut

débit sur fibres optiques

Le ou la candidat(e) sera formé(e) sur les compétences requises pour mener à bien les missions choisies.

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-04 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Physique des particules
Code:
Ingenieur-2122-EL-04
Caractérisation de lignes de transmission rapides sur plateformes électroniques de test à base de FPGA
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Description:

Le Centre de physique des particules de Marseille est une unité mixte de recherche (UMR 7346) qui relève du CNRS, et d'Aix-Marseille Université. Le CPPM travaille notamment sur l'expérience ATLAS basée au CERN à Genève, le plus puissant accélérateur de particules au monde. Le CPPM est l'un des membres d'une collaboration internationale de 3 000 scientifiques issus de 174 instituts, représentant pas moins de 38 pays. Une mise à niveau («~upgrade~») dATLAS doit être opérée à l'horizon 2026. Dans ce cadre,le CPPM participe fortement à l'upgrade du système d'acquisition des données et de trigger. Cette activité de R\&D a amené l'équipe du CPPM à développer une plateforme de test au format ATCA, standard très utilisé dans le monde des Télécoms. Cette carte de haute densité (20 couches), intègre 24 modules optiques et deux FPGA INTEL Stratix 10 de dernière génération. Elle permettra de mettre en uvre des liaisons série sur fibres optiques à très haut débit (jusqu'à 25 Gbit/s). Ces liaisons sont basées sur des protocoles propriétaires du CERN tolérants aux radiations. Cette carte permettra également de valider les composants, ainsi que le challenge technique de gestion de la consommation et la dissipation thermique.

Activité principale :

Le ou la stagiaire sera intégré(e) à l'équipe de développement. Le travail proposé est un travail de R\&D destiné à caractériser par différentes approches l'intégrité des transmissions électriques et optiques à très haut débit jusqu'à 25 Gbps.

Cette évaluation s'effectuera à travers l'emploi de différentes techniques et technologies mises en uvre autour de l'outil de diagnostic embarqué sur FPGA~ODI pour «~On-Die Instrumentation~» , d'instruments de mesures de pointe et de logiciels d'analyse et de simulation d'intégrité de signaux sur circuit imprimé. Ce travail d'évaluation nous permettra de confronter les résultats pour comprendre les phénomènes observés et proposer des solutions optimisant la qualité des signaux. Le but est d'élargir notre expertise dans la conception de cartes numériques pour lesquelles les débits augmentent perpétuellement.

Ce travail permettra à l'étudiant d'approfondir plusieurs domaines techniques~:

- l'étude des architectures électroniques des cartes à base de FPGA

- le développement de code VHDL pour FPGA qui solliciteront notamment l'ODI

- la caractérisation des liens sériels en mesurant le diagramme de l'il

avec un oscilloscope de pointe (type Serial Data Analyser de chez Lecroy)

et en mesurant les jitters.

- La simulation des liens sériels par l'outil SIGRITY sous CADENCE.

Le ou la stagiaire sera accueilli(e) au sein du service électronique qui possède un savoir-faire étendu et reconnu dans le design de firmware FPGA et la conception de cartes électroniques rapides à haute densité.

Le travail s'effectuera dans un environnement de recherche international. Des déplacements au CERN à Genève sont à prévoir en vue d'assister à des réunions de collaboration et y présenter son travail~.

Connaissances requises :

- Bonnes connaissances en électronique générale et en instrumentation,

- Bonnes connaissances en design FPGA en langage VHDL,

- Développements d'outils logiciels en langage C, C++, Python, LabView

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-06 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Physique des particules
Code:
Ingenieur-2122-EL-06
Développement et mise au point d'un banc de tests pour la caractérisation de circuits intégrés dans le cadre de l'expérience ATLAS du CERN
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Description:

ATLAS («~A Toroidal LHC ApparatuS») est une expérience de physique des particules installée auprès du LHC («~Large Hadron Collider~») au CERN («~Centre Européen pour la Recherche Nucléaire~») situé à Genève. Elle a été conçue pour tester de nouveaux modèles de physique, et rechercher les signatures de nouvelles particules, telles que le boson de Higgs dont l'existence a été découverte expérimentalement en 2012.

En prévision d'une jouvence complète du détecteur à pixel de l'expérience, une collaboration internationale, RD53 a été mise en place pour développer le prochain circuit de lecture associé au détecteur en technologie CMOS~65~nm. Le CPPM fait partie de cette collaboration et a en charge plusieurs cellules implantées dans le circuit global comme un ADC de type SAR permettant la numérisation des informations provenant de références de tension, dosimètres, et capteurs de température. Il a également la responsabilité de la conception de mémoires tolérantes au SEU («~Single Event Upset~») et exerce une activité dans le groupe «~Radiation Tolerance~» puisque l'ASIC de lecture devra fonctionner dans un environnement très radioactif, supportant une dose totale de 500~Mrad (5~MGray) pendant 5 ans d'exploitation.

Activité principale :

Plusieurs prototypes de circuits intégrés (CI) ont été conçus en différentes technologies, 65~nm, 28~nm, etc et testés sur table ainsi qu'en irradiation au CERN. Les tests de ces CI permettent la validation de leur architecture auprès de la collaboration où les résultats sont présentés. Un banc de tests de CI prototypes a été développé au CPPM. Il est basé sur une carte du commerce nanoPC de type BeagleBone, communicant avec un FPGA (Altera-Cyclone III) via un bus parallèle de type GPMC (General-Purpose Memory Controller). Les séquences de tests sont préalablement implantées dans le FPGA (programmation VHDL), Le contrôle-commande s'effectue au niveau de la carte BeagleBone en C++. D'autres paramètres tels que, la consommation, la température, les niveaux d'alimentation, sont enregistrés via un bus I2C. Ces éléments sont indispensables pour s'assurer du

Le stage de 6 mois devra comporter plusieurs étapes~:

- Prise en main du banc de test.

- Maitrise, débogage des différentes fonctions du banc.

- Amélioration et finalisation de l'ensemble, paramétrage intuitif et convivial via une interface utilisateur de type Qt Python.

Connaissances requises :

Le(la) candidat(e) devra posséder de bonnes bases en électronique ainsi que de solides connaissances en programmation VHDL, C++, Qt Python

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-07 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Electronique
Code:
Ingenieur-2122-EL-07
Implémentations de circuits neuronaux sur différents FPGAs, évaluation de performances
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Le Centre de Physique des Particules de Marseille, unité mixte CNRS/Aix-Marseille

Université, (http://marwww.in2p3.fr) est un des laboratoires de l'Institut National de Physique Nucléaire et de Physique des Particules (IN2P3), institut du CNRS qui regroupe les moyens de la physique des particules. Le CPPM travaille notamment sur des systèmes d'acquisition sur le LHC, l'accélérateur de particules et collisionneur proton-proton le plus puissant du monde, au CERN à Genève (http://www.cern.ch).

Le nombre de collisions va dans un avenir proche être multiplié par 10, rendant difficile l'identification des particules générées tant elles seront nombreuses.

Une piste possible est d'utiliser des algorithmes neuronaux au plus près du détecteur pour trier et identifier les particules générées ainsi que les phénomènes recherchés. The challenge est que le LHC génère 40 millions de collisions par seconde, chacune d'entre elles «~illuminant~» des dizaines, voire des centaines de milliers de capteurs. Il est donc nécessaire d'implémenter ces algorithmes «~au vol~» sur des FPGAs très puissants.

L'objet du projet THINK (Testing Hardware Instantiations of Neural Kernels) est d'évaluer la capacités de FPGAs ou de circuits spécialisés tels que des chips neuromorphiques à traiter ce type de données en temps réel.

Activité principale :

L'évaluation consistera à hiérarchiser les performances de différents types de FPGAs ou chips neuromorphiques en implémentant plusieurs benchmarks communs. L'évaluation portera non seulement sur les performances mais aussi sur la qualité des outils de mise en uvre, notamment leur facilité d'emploi ou leur versatilité.

Deux types de FPGAs relativement différents seront étudiés~:

- Le Stratix NX d'Intel doté d'AI Tensor Blocks répartis dans le FPGA

- Le Versal AI de Xilinx doté d'un processeur scalaire avec accélérateur de fonctions AI

Si le temps le permet un chip neuromorphique ou un GPU sera également étudié.

Connaissances apréciées

- Conception FPGA en langage VHDL, HLS~;

- Langage Python~;

- TensorFlow, Queras, Pytorch.

Contact : CV + lettre de motivation avec la référence « LHCb_Conception » à

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Electronique
Code:
Ingenieur-2122-EL-08
Conception d'un circuit de réception optique en CMOS 28 nm pour les futures expériences du CERN
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Le stage se déroule au Centre de Physique des Particules de Marseille (CPPM), une unité mixte de recherche (UMR 7346) qui relève de l'IN2P3, institut regroupant les activités de physique des particules et de physique nucléaire au sein du CNRS et d'Aix-Marseille Université.

Le CPPM participe depuis plusieurs années au projet à l'expérience ATLAS du CERN à Genève, au sein d'une collaboration internationale de plus 3 000 scientifiques issus de 174 instituts, représentant pas moins de 38 pays.

L'un des grands challenges techniques au niveau de l'expérience ATLAS réside dans l'augmentation du nombre de données à acheminer depuis le détecteur vers les centres de calculateurs et les circuits intégrés spécifiques très haut débit et durcis contre les irradiations sont des éléments essentiels pour la transmission de ces données.

Le CPPM associé à des équipes du CERN, s'intéresse à la conception de l'ASIC de réception optique pour les futures mises à niveau de l'expérience ATLAS. Le circuit devrait utiliser le process CMOS 28 nm et fonctionner à un débit supérieur à 20 Gbp/s.

Activité principale :

Le but du stage est de proposer une architecture haute vitesse, très bas bruit très basse consommation pour le circuit de transmission de données. Le circuit est par la suite conçu en utilisant le process CMOS 28~nm.

Le stage de 6 mois sera organisé en plusieurs étapes :

- Etude de l'interface de transmission des données à haut débit

- Etude et optimisation du circuit d'émission ou de réception à 20~Gbit/s

- Etude des effets de la dose ionisante

- Simulation et optimisation du circuit sous Cadence Virtuoso

- Dessin des masques sous cadence

Connaissances requises :

- Bonnes connaissances en conception de circuits analogiques CMOS

- Le développement de bancs de test basés sur des composants programmables

de type FPGA est considéré comme un avantage.

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-02 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Electronique
Code:
Ingenieur-2122-EL-02
Développement de la carte DAQTemp pour le système d'acquisition du projet TIARA
Internship supervisor:
Frédéric Hachon - 04 91 82 76 71 - hachon@cppm.in2p3.fr
Sorry, this position is no longer available
Description:

Le Centre de Physique des Particules de Marseille, unité mixte CNRS/Aix-Marseille Université est un des laboratoires de l'Institut National de Physique Nucléaire et Physique des Particules (IN2P3), institut du CNRS qui regroupe les moyens de la physique des particules.

Le CPPM participe au projet TIARA (Time-of-flight Imaging Array), dont l'objectif est de réduire les incertitudes liées au parcours des protons lors de traitements par protonthérapie grâce au développement d'un détecteur pour l'imagerie par temps-de-vol des gammas prompts créés lors de l'irradiation.

Ce détecteur consiste en un ensemble de convertisseurs cherenkov en fluorure de plomb entourant le volume irradié et lus en coïncidence avec un moniteur de faisceau. Le temps-de-vol entre les pixels de fluorure et leurs positions permettent de reconstruire le parcours des protons en temps réel.

Le CPPM est en charge du développement du système d'acquisition de données du projet TIARA basé sur la carte DAQTemp, qui permet de lire simultanément 64 SiPM et d'étiqueter en temps et en énergie les événements avec une résolution inférieure à 100 ps. Cette carte est dotée d'un FPGA Intel Arria 10, de circuits ASIC pour la lecture des SiPM et d'un système d'horloge d'une précision de 100 fs.

Activité principale :

Pour la mise au point du système d'acquisition de données du projet TIARA, il s'agit de poursuivre, avec l'ensemble de l'équipe, le développement du firmware FPGA, du software commande-contrôle de la carte DAQTemp ainsi que du software de calibration, d'analyse et de traitement de données des événements détectés par les SiPM.

Ces développements utiliseront principalement les langages VHDL, Python et C++.

Le ou la stagiaire sera accueilli(e) au sein du service électronique du CPPM, composé d'une vingtaine de personnes, qui possède un savoir-faire étendu dans la programmation des FPGA de la marque Intel/Altera et dans la conception de cartes d'acquisition à grande bande passante pour des expériences de physique des particules telles que celles menées au CERN.

Connaissances requises :

- Conception FPGA en langage VHDL sous Quartus et simulation Modelsim;

- Programmation en C/C++, des connaissances en Qt seraient un plus;

- Programmation en Python pour l'analyse et le traitement de données;

- Des tests de caractérisation sur les cartes sont à prévoir.

Contact : CV + lettre de motivation avec la référence « Ingenieur-2122-EL-05 »

Frédéric HACHON, Ingénieur de Recherche CPPM

Tél : +33 4 91 82 76 71 - Mél : hachon@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Physique des particules
Code:
Ingenieur-2122-EL-05
Instrumentation
Contrôle-commande et traitement du signal d'un banc interférométrique pour la mesure des ondes gravitationnelles dans le cadre de la mission spatiale LISA de l'ESA
Internship supervisor:
Aurélia Secroun - 04 91 82 72 15 - secroun@cppm.in2p3.fr
Description:

La mission LISA (https://www.elisascience.org) est un projet satellite majeur de l'ESA dont l'objectif est de détecter des ondes gravitationnelles par mesure interférométrique grâce à une constellation de trois satellites en orbite autour du soleil. Un consortium de dix laboratoires français, dont le CPPM fait partie, s'est engagé à intégrer et tester les instruments à bord de LISA et le CPPM en particulier est responsable de la mise en uvre du contrôle-commande (CC) du banc de test qui comprend tout le pilotage et monitoring du banc ainsi que la mise en place de tests automatisés.

Activité principale~:

Dans ce cadre, un démonstrateur de banc interférométrique est en cours de développement. Deux séries de tests sont prévues~: une première série à l'APC (à Paris) fin 2021 pour laquelle une première version du code CC réalise l'acquisition et l'affichage en temps réel des données.~Pour la deuxième série de tests, planifiée fin 2022, le banc sera installé en salle propre au LAM (à Marseille) pour des tests fins et entièrement automatisés. Le CC doit piloter les composants critiques de ce banc, à savoir deux lasers «~maison~» fonctionnant à 1064~nm qui génèrent le signal interférométrique, des injecteurs fibrés qui permettent de contrôler finement l'alignement des faisceaux, et des photodiodes à quadrants lues par des phasemètres qui mesurent le signal interféromètrique à la recherche d'un minuscule décalage de phase significatif du passage d'une onde gravitationnelle. L'ensemble des instruments à piloter est accessible depuis le CPPM par une prise de contrôle à distance via un LAN Gbit.

L'objectif de ce stage sera de prendre en main le pilotage des paramètres critiques tels que l'alignement des faisceaux laser, leur fréquence ou leur amplitude de fonctionnement et de mettre en place l'automatisation des tests qui seront réalisés à Marseille. Ainsi l'ingénieur?e-stagiaire devra~:

Prendre en main le code existant et l'adapter à l'environnement du LAM

Ajouter au code existant des commandes sous forme de fonction paramétrable

Mettre en place l'automatisation sous forme de scripts

L'ingénieur?e stagiaire sera amené?e à participer aux réunions du projet pour exposer son travail.

Connaissances requises~:

Base technique solide en instrumentation

Base solide en programmation en langage Python

Bonnes connaissances en traitement du signal

Connaissance de la Raspberry PI considéré comme un atout supplémentaire

Contact~: CV + lettre de motivation avec la référence «~LISA~» à

Aurélia Secroun, Ingénieure Chercheure CPPM

Tel~: 04 91 82 72 15 email~: secroun@cppm.in2p3.fr

Le stage de 6 mois sera conventionné et rémunéré.

Keywords:
Instrumentation
Code:
Ingenieur-2122-IS-01
imXgam
Development of the wireless control and data acquisition system for the MAPSSIC intracranial probe
Internship supervisor:
Mathieu Dupont - mdupont@cppm.in2p3.fr
Description:

The Marseille Particle Physics Center is a mixed research unit (UMR 7346) dependent on the CNRS and Aix-Marseille University, which deploys its research activities both in the field of fundamental physics and also for applications based on ionizing radiation.

Satiety or addiction circuits are driven in the brain by negative or positive feedback loops using neurotransmitters. These circuits can be imaged by positron emission tomography (PET) thanks to the labeling of neurotransmitters by positron-emitting radioactive ions, such as, for example, cocaine labeled with 11C.

However, PET scans require the subject to be anesthetized, which does not capture the actual behavior of the brain under waking conditions.

The CPPM is participating in the MAPSSIC project, which consists of developing an intracranial CMOS pixel probe for positron imaging in vigilant and free-moving rats. The IMIC probe, which forms a needle of several hundred active CMOS pixels, was developed by the IPHC in Strasbourg to be permanently implanted in the brain of a rat which, equipped with a backpack including a battery and a wireless transmitter linked to the CMOS pixels, will make it possible to directly image the positrons emitted during the disintegration of the nuclei of a radioactive tracer attached to the molecules of the neurotransmitter studied.

Main activity :

The trainee will be integrated into the MAPSSIC project will participate in the design study and the implementation of a wireless solution to ensure the monitoring and control and transmission of data collected simultaneously by 4 probes IMIC to an acquisition PC.

This wireless solution must be carried in a backpack adapted to the build of a rat and be able to achieve an autonomy of several hours corresponding to several periods of decay of the radioactive tracer used to label the neurotransmitter.

Required profile :

 Practice of C / C ++ language

 Embedded systems programming (µC) in C / C ++

 Knowledge of python is a plus

The 6-month internship will be remunerated.

Keywords:
Instrumentation
Code:
Ingenieur-2122-IM-01

# Bachelor Internship

CPPM welcomes students from bachelor levels (L1, L2 and L3) for an intership.

Applications for internships are centralized by William Gillard. To apply, send him a cover letter with your CV, your latest grades and your contact details so that he can get back in touch with you. The administrative file will be followed by Jocelyne Munoz.

Contacts : William Gillard, Jocelyne Munoz

# Secondary School

We welcome college and high school students for internships for defined periods of time. All requests must be justified but cannot be accepted, given the limited number of places.

• for college level: one week in December (before the Christmas holidays) Rescheduled to spring 2021

• for high school students: one week in June (during the baccalaureate exam period)

Contact : Jocelyne Munoz

# TIPE

Since 1998, CPPM accomodates pupils of preparatory classes in order to help them carry out their TIPE.

Most of them obtained, at the time of their TIPE test, a higher grade than the national average and succesfully integrated an engineering school.

Contact: Heide Costantini