6 sujets IRFU/DEDIP

Dernière mise à jour : 18-01-2021


• Artificial intelligence & Data intelligence

• Electronics and microelectronics - Optoelectronics

• Neutronics

• Particle physics

 

Machine learning for unmixing gravitational wave signals from the LISA interferometer

SL-DRF-21-0300

Research field : Artificial intelligence & Data intelligence
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

Laboratoire ingénierie logicielle et applications spécifiques

Saclay

Contact :

Jérôme Bobin

Starting date : 01-09-2021

Contact :

Jérôme Bobin
CEA - DRF/IRFU/DEDIP/LILAS

0169084463

Thesis supervisor :

Jérôme Bobin
CEA - DRF/IRFU/DEDIP/LILAS

0169084463

Personal web page : www.jerome-bobin.fr

Following the first detections of gravitational waves in 2015, that were awarded the Nobel prize in Physics in 2017, a new window is now open to observe our Universe. In contrast to ground-based interferometers, the LISA observatory (Laser Interferometer Space Antenna) will be sensitive to a very large number of signals of different physical natures: galactic binaries, supermassive black holes, extreme mass ratio inspirals, etc. This wealth of signals raise paramount data analysis challenges: unmixing a large number of gravitational events of very different nature. The goal of this PhD thesis is to develop the first gravitational signal unmixing method for LISA. The proposed approach will make use of adapted signal representations for each category of signals to be retrieved, which will make profit of their different temporal signatures. The design of such representations will be based on advanced machine learning techniques. The proposed methods will be evaluated with the participation to the LISA Data Challenges (LDC).
Design of a new readout circuit for highly pixelated hybrid detectors for hard X-ray spectro-imaging and polarimetry space applications.

SL-DRF-21-0346

Research field : Electronics and microelectronics - Optoelectronics
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

Systèmes Temps Réel, Electronique d’Acquisition et Microélectronique

Saclay

Contact :

Olivier GEVIN

Olivier LIMOUSIN

Starting date : 01-10-2021

Contact :

Olivier GEVIN
CEA - DSM/IRFU/SEDI

0169081716

Thesis supervisor :

Olivier LIMOUSIN
CEA - DRF/IRFU/DAP/LSIS

01 64 50 15 03

This space instrumentation thesis consists in designing a microelectronic matrix circuit integrating numerous analog and digital functions in 250 µm pixels for the reading of CdTe or silicon semiconductor detectors.

Since 2011, our research team has been developing a new concept of hybrid detectors called MC2 (Mini CdTe on Chip) based on 3D WDoD(TM) (wireless die on die) technologies that should support the thermomechanical and radiative environment of a space mission. The ambition is to realize large focal planes with unequalled performances in time-resolved spectro-imaging and polarimetry, intended to serve the next discoveries in X and gamma astrophysics and solar flare physics.

The targeted microelectronics technology is the XFAB 180 nm technology, which is particularly attractive for space applications due to its perennial and affordable commercial availability and its good radiation resistance. It is a credible choice as an alternative to the AMS 0.35 µm technology, massively exploited until now, especially for the space projects SVOM (gamma camera ECLAIRs) and Solar Orbiter (X STIX telescope) in our group. Future generations of our detectors will be able to benefit from this advantageous technology in R&D as well as in production, even in cases where the dose resistance is important.

Two generations of matrix circuits realized in the XFAB 180 nm technology have shown very promising results to integrate ultra low noise and low power self-triggered spectroscopy chains in a 250 µm pixel side. These circuits have also shown the need to design, characterize and optimize several critical functions at the pixel level, common blocks and inter-pixel operators in order to obtain a better response uniformity and the desired ultimate noise level. The objective of the thesis is to provide innovative and high-performance solutions for a new circuit of 32 x 32 pixels with a 250 µm pitch, connectable on 2 sides, with an optimized interface and a modular architecture to be integrated in a spatially-integrated detection module.

Spinoffs from these developments are also envisaged in the medical field, notably for breast cancer tomography, as well as in the field of environmental monitoring in the nuclear field.
Design of a novel Analog to Digital Converter with internal Machine Learning calibration

SL-DRF-21-0349

Research field : Electronics and microelectronics - Optoelectronics
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

Systèmes Temps Réel, Electronique d’Acquisition et Microélectronique

Saclay

Contact :

Fabrice Guilloux

Philippe Schwemling

Starting date : 01-10-2021

Contact :

Fabrice Guilloux
CEA - DRF/IRFU/DEDIP/STREAM

33 1 69 08 67 31

Thesis supervisor :

Philippe Schwemling
CEA - DRF/IRFU/DPHP/Atlas

33 1 69 08 85 85

Laboratory link : http://irfu.cea.fr/dedip/index.php

In current and future high energy physics experiments (as the LHC at CERN), the particle detector uses sub-micron integrated circuits. The signals from these circuits are digitized upstream of the processing chain and conveyed far from the experience by ultra-fast digital links. The development of new analog to digital converters (ADC) that perform well in potentially extreme environments, especially in radiation environments, is a challenge. Up to now, the trend has been to make these circuit responses stable and insensitive to variations in T°, dose or technology. Another possibility is to establish precise calibration tables that can be "downloaded" into the ASIC when conditions change or, even better, automatically generated by the ASIC itself.



This calibration parameter generation, in or outside of the ASIC, can be considered in the Machine Learning (ML) context.



The thesis approach is therefore to understand both the complexity of a real ADC and the software analysis of the errors correction, by carrying out the ML algorithms resulting in the ADC calibration. With an accurate ADC calibration, it is also foreseen to greatly enhanced the ADC performance by combining several ADC channels into one, leading to conversion rates or resolutions unreachable for a single core ADC.

Neutron and beta imaging with Micromegas detectors with optical readout

SL-DRF-21-0319

Research field : Neutronics
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

DÉtecteurs: PHYsique et Simulation

Saclay

Contact :

Thomas PAPAEVANGELOU

Esther FERRER RIBAS

Starting date : 01-10-2021

Contact :

Thomas PAPAEVANGELOU
CEA - DRF/IRFU/DEDIP/DEPHYS

01 69 08 2648

Thesis supervisor :

Esther FERRER RIBAS
CEA - DRF/IRFU/DEDIP/DEPHYS

0169083852

Personal web page : http://irfu.cea.fr/Pisp/esther.ferrer-ribas/

Laboratory link : http://irfu.cea.fr/dedip/index.php

Recent developments have shown that coupling a Micromegas gaseous detector on a glass substrate with a transparent anode and a CCD camera enable the optical readout of Micromegas detectors with an impressive spatial resolution showing that the glass Micromegas detector is well-suited for imaging. This feasibility test has been effectuated with low-X-ray photons permitting energy resolved imaging. This test opens the way to different applications. Here we will focus, on one hand, on neutron imaging for non-destructive examination of highly gamma-ray emitting objects, such as fresh irradiated nuclear fuel or radioactive waste and on the other hand, we would like to develop a beta imager at the cell level in the field of anticancerous drug studies.

Both applications require gas simulations to optimize light yields, optimization of the camera operation mode and design of the detectors in view of the specific constraints of reactor dismantling and medical applications: spatial resolution and strong gamma suppression for neutron imaging and precise rate and energy spectrum measurements for the beta. The image acquisition will be optimized for each case and dedicated processing algorithms will be developed.

Axion searches with the International Axion Observatory with ultra low background Micromegas detectors

SL-DRF-21-0302

Research field : Particle physics
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

DÉtecteurs: PHYsique et Simulation

Saclay

Contact :

Thomas PAPAEVANGELOU

Esther FERRER RIBAS

Starting date : 01-10-2021

Contact :

Thomas PAPAEVANGELOU
CEA - DRF/IRFU/DEDIP/DEPHYS

01 69 08 2648

Thesis supervisor :

Esther FERRER RIBAS
CEA - DRF/IRFU/DEDIP/DEPHYS

0169083852

Personal web page : http://irfu.cea.fr/Pisp/esther.ferrer-ribas/

Laboratory link : http://irfu.cea.fr/dedip/index.php

More : https://iaxo.web.cern.ch/content/home-international-axion-observatory

Axions were introduced as the most promising solution in explaining the absence of Charge-Parity symmetry violation in the strong interaction. These neutral, very light particles, interact so weakly with ordinary matter that they could contribute to the Dark Matter. Axion search techniques rely on their interaction with photons. Helioscopes search for axions produced in the solar core by the conversion of plasma photons into axions giving rise to a solar axion flux at the Earth surface, with energy spectrum at the region 1-10 keV.

The International Axion Observatory (IAXO) will achieve a signal-to-background ratio of about 4-5 orders of magnitude better than most sensitive experiments today. BabyIAXO, an intermediate experimental stage of IAXO, will be hosted at DESY (Germany). BabyIAXO is conceived to test all IAXO subsystems (magnet, optics and detectors) at a relevant scale for the final system and thus serve as prototype for IAXO, but at the same time as a fully-fledged helioscope with relevant physics reach in itself, and with potential for discovery. IAXO and BabyIAXO will be equipped with X-ray optics coupled to low background X-ray detectors. The required levels of background are extremely challenging, a factor 10 better than current levels.

The PhD will work on the X-ray detector development in particular of the new generation of Micromegas detectors. The development will be focused on the optimization of the background level by a multi-approach strategy coming from ground measurements, screening campaigns of components of the detector, underground measurements, background models, in-situ background measurements as well as refinement of rejection algorithms. Physics analysis of BabyIAXO data is expected in the last year of the PhD.

Towards a high spatial resolution pixel detector for particle identification: new detectors contribution to physics

SL-DRF-21-0714

Research field : Particle physics
Location :

Département d’Electronique, des Détecteurs et d’Informatique pour la physique (DEDIP)

DÉtecteurs: PHYsique et Simulation

Saclay

Contact :

Nicolas FOURCHES

Starting date : 01-09-2021

Contact :

Nicolas FOURCHES
CEA - DRF/IRFU/DEDIP/DEPHYS

0169086164

Thesis supervisor :

Nicolas FOURCHES
CEA - DRF/IRFU/DEDIP/DEPHYS

0169086164

More : https://doi.org/10.1109/TED.2017.2670681

Future experiments on linear colliders (e+e-) with low hadronic background require improvements in the spatial resolution of pixel vertex detectors to the micron range, in order to determine precisely the primary and secondary vertices for particles with a high transverse momentum. This kind of detector is set closest to the interaction point. This will provide the opportunity to make precision lifetime measurements of short-lived charged particles. We need to develop pixels arrays with a pixel dimension below the micron squared. The proposed technologies (DOTPIX: Quantum Dot Pixels) should give a significant advance in particle tracking and vertexing. Although the principle of these new devices has been already been studied in IRFU (see reference), this doctoral work should focus on the study of real devices which should then be fabricated using nanotechnologies in collaboration with other Institutes. This should require the use of simulation codes and the fabrication of test structures. Applications outside basics physics are X ray imaging and optimum resolution sensors for visible light holographic cameras.

 

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