Dissertations / Theses on the topic 'Chambres à projection temporelle (physique)'
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Antilogus, Pierre. "Calibration de la TPC de DELPHI pour la mesure du dE/dx : étude des oscillations des mésons beaux dans DELPHI." Paris 7, 1988. http://www.theses.fr/1988PA077003.
Full textThe TPC (Time Projection Chamber) of DELPHI which gives 16 tridimensional space-points for each charged track, is fondamental in the reconstruction of L. E. P. Events with complex topology. This detector with its measurement of the energy lost by particles in the Ar/CH4 mixture, permits also separation between electron and pion at 3 standard deviations below 7. 5 GeV. In this thesis we develop the control of systematic errors in the energy lost measurement. More precisely, we present results on the 12 TPC proportional chambers calibration. With these measurements we can use the identification power of the TPC in the best condition. In the second part of this thesis, we develop different methods on the beauty meson oscillation measurement. We estimate the possibility for the DELPHI detector in this sector. Particularly, we introduce the differential measurement of the oscillation which seems to be the only method to have access to the maximal mixing of the B⁰s √ B⁰s mesons
Macaire, Michael. "Etude des oscillations de neutrinos muoniques en neutrinos électroniques auprès de l'expérience T2K." Paris 7, 2012. http://www.theses.fr/2012PA077251.
Full textT2K is a long baseline neutrino experiment currently running in Japan, which aims at measuring the mixing angle 013. The experiment uses a high intensity beam of muon neutrinos, and observes the oscillations into electron neutrinos, ve, at the Super-Kamiokande detector, 295 km away from the neutrino source. This thesis presents a measurement of the intrinsic beam contamination in electron neutrinos, which is the dominant background when looking for this kind of oscillations. As an introduction to the analysis, the T2K experimental setup is presented, as well as the first published T2K oscillation results. The beam contamination measurement is made from a data set taken in 2010 and 2011 by the near detector of the experiment, located at 280 m from the beam source. Selection criteria are defined to create two samples of charged current electron neutrino interactions and charged current vii interactions, in order to calculate the ratio of the number of interactions and estimate the beam contamination. The result is in agreement with the beam simulation and shows a contamination in ve of the order of 1%. This thesis also contains a study of the alignment of the MicroMegas modules on the near detector TPCs. It is shown that misalignments between modules can introduce a bias in the momentum mea-surement of the charged particles crossing the TPCs. Cosmic ray data is used to determine the relative misalignments between modules and correct the related effects in the event reconstruction
Ascher, Pauline. "Étude de la radioactivité deux protons de 54Zn avec une chambre à projection temporelle." Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14376/document.
Full textThe study of nuclei at the proton drip-line is a recent and efficient tool to prove the nuclearstructure far from stability. In particular, the two proton radioactivity phenomenonpredicted in 1960 has been discovered in 2002. This PhD thesis concerns an experiment realisedat GANIL, in order to study the 2p radioactivity of 54Zn with a time projection chamber,developed for the individual detection of each proton and the reconstruction of their tracksin three dimensions. The data analysis allowed to determine the correlations in energy andangle between the two protons. They have been compared to a theoretical model, which takesinto account the dynamics of the emission, giving information about the structure of theemitter. However, due to the very low statistics, the interpretation of the results is limitedbut these results open very interesting prospects for further studies of nuclei at the limits ofthe existence
Pibernat, Jérôme. "Conception d'une électronique de traitement de signaux de forte dynamique issus d'une chambre à projection temporelle." Bordeaux 1, 2007. http://www.theses.fr/2007BOR13600.
Full textThe emphasis on many-particles radioactive decays requires a tracking detector like a Time Projection Chamber (TPC), which operating point can be set in accordance with the nucleides analyzed. The electrical model of such a detector reveals that, depending on its operating conditions and the nature of elements under study, the signals dynamic range can be up to more than five orders of magnitude. Consequently, an application specific processing system has to be designed. To meet the requirements of the experimental equipment, this system muste be integrated and its functional architecture muste be similar to the one of the prototype presented. The topology of the input stage of the protoype narrows the dynamics of the processing. The solution suffested to solve this problem consists in substituting this stage by a second generation current conveyor (CCII) with multiple outputs. The study of its linearity leads to predict the highest signal amplitude that it's able to process. A dynamic range greater than 1. 10(5) obtained in simulation with adapted filters. Optimization of this conveyor and filters coukd lead to extend even more this dynamic range
Wang, Wenxin. "Etude d’un grand détecteur TPC Micromegas pour l’ILC." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112099/document.
Full textThe study of the fundamental building blocks of matter necessitates always more powerful accelerators. New particles are produced in high energy collisions of protons or electrons. The by-Products of these collisions are detected in large apparatus surrounding the interaction point. The 125 GeV Higgs particle discovered at LHC will be studied in detail in the next e⁺e⁻ collider. The leading project for this is called ILC. The team that I joined is working on the R&D for a Time Projection Chamber (TPC) to detect the charged tracks by the ionization they leave in a gas volume, optimised for use at ILC. This primary ionization is amplified by the so-Called Micromegas device, with a charge-Sharing anode made of a resistive-Capacitive coating. After a presentation of the physics motivation for the ILC and ILD detector, I will review the principle of operation of a TPC (Chapter 2) and underline the advantages of the Micromegas readout with charge sharing. The main part of this PhD work concerns the detailed study of up to 12 prototypes of various kinds. The modules and their readout electronics are described in Chapter 3. A test-Bench setup has been assembled at CERN (Chapter 4) to study the response to a ⁵⁵Fe source, allowing an energy calibration and a uniformity study. In Chapter 5, the ion backflow is studied using a bulk Micromegas and the gas gain is measured using a calibrated electronics chain. With the same setup, the electron transparency is measured as a function of the field ratio (drift/amplification). Also, several beam tests have been carried out at DESY with a 5 GeV electron beam in a 1 T superconducting magnet. These beam tests allowed the detailed study of the spatial resolution. In the final test, the endplate was equipped with seven modules, bringing sensitivity to misalignment and distortions. Such a study required software developments (Chapter 6) to make optimal use of the charge sharing and to reconstruct multiple tracks through several modules with a Kalman filter algorithm. The results of these studies are given in Chapter 7. The TPC technique has been applied to neutron imaging in collaboration with the University of Lanzhou. A test using a neutron source has been carried out in China. The results are reported in Chapter 8
Lázaro, Roche Ignacio. "Design, réalisation et test in situ d’une caméra muon pour des applications en sciences de la terre et en génie civil." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4074/document.
Full textThis thesis is dedicated towards the creation of a new direction-sensitive tool for muon flux measurement based on a thin time projection chamber with a Micromegas readout, to achieve a compact detector with an angular resolution compatible with civil engineering and geophysics imagery and monitoring applications. The main motivation is to develop a detector capable to fill the technological gap for applications with compactness and transportability constraints. The dissertation provides a review of the different existing muon detection technologies and their diverse fields of application. Two muon imaging techniques are introduced: transmission and scattering muography. Transmission muography, more suitable for big targets, is based on the attenuation of the natural-occurring cosmic-muon flux due to the opacity of the material they traverse. This non-destructive, passive technique provides original information that can be used for imaging purposes. The work covers the methodology used towards the characterization of the incidental muon flux both on the surface and in underground conditions. A detailed description of the physical processes triggered by the passage of a muon through the detector is provided. Results of the simulations of the signal formation processes are presented and discussed to justify the design choices of the key components so as to meet performance requirements in term of temporal, spatial and angular resolution. The influence of operational or external parameters such as the gain, temperature or presence of contaminants is covered as well. The thesis describes in detail the principal phases of design and assembly of the MUST2 detector, including: (i) the design of the Micromegas readout layout, (ii) the choice of gas, (iii) the conception of an electric field homogenizer, (iv) the choice of the electronics instrumentation and its trigger signal, and (v) the creation of an auxiliary system to manage the gas. The versatility of MUST2 has been proved with the successful use of different trigger options and electronics. The data is acquired by means of software developed for the CERN’s Scalable Readout System electronics and subsequently analyzed with a muon trajectory reconstruction algorithm, which retrieves the: time of passage, 2D position, zenith and azimuth angles of the muons traversing the detector. The characteristics, performance and limitations of the data acquisition chain are presented and evaluated, a series of guidelines towards the improvement of its efficiency of are provided. A series of characterization tests has been carried out in different environments: controlled muon beam, open sky, at the bottom of a valley and in underground conditions. These tests have enabled a better understanding of the performance of the detector and allowed to tune up its operational parameters. Despite the weak statistics of the test runs, the measured muon flux has shown a good correlation with the surrounding target volumes. A campaign of measurements in real field conditions has been carried out at the Saint-Saturnin-les-Apt (Vaucluse, France) dam. The experimental results obtained are in consonance with the values anticipated by the digital model, the field transportability and the capability to perform long-term out-of-lab measurements have been demonstrated. On the downside, the impact of the external temperature on the data acquisition should be balanced out to get a steady acquisition and monitor the temporal evolution of the muon flux. In conclusion, the successful proof-of-concept trial allows to validate the MUST2 camera for transmission muography purposes
Goigoux, Thomas. "Etude de la radioactivité deux-protons de 67Kr et développement d’une chambre à projection temporelle." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0706/document.
Full textTwo-proton radioactivity is a decay mode of proton-rich nuclei located beyond the proton nuclear existence limit (drip line). Predicted in the 1960s, this process was observed for the first time in 2002 in the 45Fe decay study. Only four two-proton emitters were known so far: 45Fe, 48Ni, 54Zn and 19Mg. A search for new emitters was performed with the EURICA- WAS3ABi setup at the RIKEN Nishina center in 2015. The decay of 59Ge, 63Se, 67Kr and 68Kr was observed for the first time. Two-proton radioactivity of 67Kr together with the beta and delayed proton decay of exotic nuclei in the region were studied. A time projection chamber (TPC) developed at the CENBG (2004-2011) enabled the study of the correlations between the protons for 45Fe and 54Zn. A second generation of TPC is under construction within the ACTAR TPC (ACtive TARget for TPC) collaboration. This detector enables a reconstruction in three dimensions of the energy deposited in the active volume which allows a more efficient reconstruction of the tracks as compared to the previous TPC. The generic electronics GET (General Electronics for TPCs) manages the processing and acquisition of the signals. The characterisation of the GET electronics and the TPC demonstrator at CENBG is devoted to the second aspect of this PhD work
Caiulo, Davide. "Charge readout analysis in Liquid Argon Time Projection Chambers for neutrino and astro-particle physics." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1065/document.
Full textThis is an important period for High Energy Physics: many recent results, including the Higgs discovery and its characterization, confirm the Standard Model. A crucial point for the future of Particle Physics is the study of neutrino masses and mixing representing the first established evidence of physics beyond the SM. Since 2011, the large value of the ?13 mixing angle opened the way to the investigation of CP violation in the neutrino sector. A next generation long baseline neutrino experiment (DUNE) has unprecedented potential to precisely measure the neutrino oscillation parameters, determine the neutrino mass hierarchy and has a very good chance to discover evidence for CP violation in the leptonic sector. The large underground neutrino detectors needed for this task will also address the search for proton decay and the observation of supernovae neutrinos. Giant Liquid Argon Time Projection Chambers (LAr TPCs) will be employed as neutrino targets and detectors. They provide bubble-chamber quality imaging coupled to excellent energy resolution and particles identification capabilities. Neutrino interactions produce secondary particles, which ionize the liquid argon. The ionization electrons drift for long distances along a uniform electric field until they reach finely segmented and instrumented anodes, producing electrical signals that are used for 3D imaging and analysis of the primary interactions. The dual-phase readout technique foresees the amplification of the ionization signal in avalanches occurring in the gas phase above the liquid argon level. This technique further enhances the performance of the LAr TPC by increasing its signal to noise ratio. The subject of thesis is the ionization charge reconstruction and analysis in the dual-phase LAr TPC: the ionization charges measurement provides information about the kinetic energy of secondary charged particles produced in neutrino interactions. In this way, it is possible to reconstruct the incoming neutrino energy, identify and reject electromagnetic shower generated by photons from pi0 decay and perform particles identification from the measurement of the specific ionization losses.The measurement of the ionization implies a detailed knowledge of the detector response and of the reconstruction algorithm. In order to achieve this knowledge a detailed analysis of the simulated energy losses has been performed by studying the differences between the theoretical knowledge and the simulation
Navrer-Agasson, Anyssa. "Direct dark matter search with the DarkSide Experiment." Thesis, Université de Paris (2019-....), 2019. https://theses.md.univ-paris-diderot.fr/NAVRER-AGASSON_Anyssa_va2.pdf.
Full textThe existence of dark matter is known because of its gravitational effects, and although its nature remains undisclosed, one of the leading candidate is the weakly interacting massive particle (WIMP) with mass of the order of 100 GeV/c2 and coupling with ordinary matter at or below the weak scale. In this context, DarkSide-50 aims to direct observe WIMP-nucleon collisions in a liquid argon dual phase time-projection chamber located deep underground at Gran Sasso National Laboratory, in Italy. This work first details the argon calibration realised by the ARIS experiment. ARIS characterised the argon response to low energy nuclear and electronic recoils, down to unprecedented energies. The nuclear quenching was measured with the best precision to this date, and the recombination probability extracted was compared to different models describing the behaviour of argon in presence of an electric field. A search for low mass WIMPs performed with DarkSide-50 data is also presented. This search focuses on the ionisation signal from the TPC, leading much to much lower detection threshold. The achieved exclusion limits are amongst the leading ones, and the most stringent for a liquid argon target. Finally a preliminary search for axions is presented. Axions are an alternative candidate to dark matter, proposed as a solution to the strong CP problem. They are detectable in DarkSide via their coupling to electrons. This search required the improvement of the modelling of the background sources, by taking into account atomic effects in beta emission spectra, as well as a redefinition of the energy scale converting the energy deposited into a number of extracted electrons. The results presented show an encouraging sensitivity to both solar and galactic axions
Audirac, Laurent. "Etude de la radioactivité 2-protons de 45Fe avec une chambre à projection temporelle." Phd thesis, Bordeaux 1, 2011. http://tel.archives-ouvertes.fr/tel-00659079.
Full textCotte, Philippe. "Le projet WA105 : un prototype de chambre à projection temporelle à argon liquide diphasique utilisant des détecteurs LEMs." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS246/document.
Full textThe WA105/ProtoDUνE-DP project is a prototyping experiment which goal is to test the Double Phase Liquid Argon Time Projection Chamber (DLArTPC) technology at large scale, to use it in the future neutrinos physics experiment DUνE. Scheduled for the end of 2026 in the USA, DUνE aims at measuring the neutrinos mass ordering and the leptonic CP symetry violation. The first part of this thesis is dedicated to tests and simulations of the detection and amplification elements of the WA105 detectors. The second part is focused on the analysis of cosmic muon tracks seen by a first prototype of 4t, operated at CERN in 2017. The DLArTPC technology is a variation of the LArTPC technology allowing for the amplification of the electrons extracted from the liquid phase to the gas phase. The Large Electron Amplifiers (LEMs) are 50x50cm² PCB plates with a thickness of 1mm, pierced by 400k holes of 500 microns diameter, covered on each side by a thin layer of copper giving a gain superior to 10. Part of this thesis work is about the simulation of electrons drifting through those LEMs to study the charge collection efficiencies. Another part of this thesis is about the measurement of important caracteristics (thickness, voltage stability) of the LEMs that are used in the 300t demonstrator of WA105, which commissionning was done in the end of August 2019. The gain is one of the main caracteristics of a DLArTPC, and it has been studied in the 4t prototype by detecting cosmic muons. Comparisons are done with previous results from 2014 from a smaller prototype of 3L, and a dedicated reconstruction program was created to analyse noisy events. The work done in the thesis allowed for a better understanding of DALrTPCs, mainly on the multiplication and drift of electrons. This knowledge will be important during the operation of the 300t demonstrator at CERN, and during the operationg of the DLArTPC module of DUνE
Giganti, Claudio. "Particule Identification in the T2K TPCs and study of the electron neutrino component in the T2K neutrino beam." Paris 11, 2010. http://www.theses.fr/2010PA112334.
Full textThis thesis is devoted to the measurement of the electron neutrino appearance with the T2K experiment. T2K is a long baseline neutrino oscillation experiment that is taking data in Japan. The neutrino beam is produced by an accelerator in JPARC and neutrinos are observed in a Near Detector, ND280, before the oscillation and in the far detector, SuperKamiokande, after the oscillation. The aim of this thesis is the measurement of the intrinsic electron neutrino component of the beam with the Near Detector. The main detector used in this measurement is the ND280 TPC. The first part of the thesis describes the method developed for the particle identification in the TPCs: the PID method is based on the measurement of the truncated mean of the charge deposited by the particles crossing the gas. The PID capabilities of the TPCs have been tested analyzing the beam test data: these data have been taken at TRIUMF where we had a beam composed by electrons, muons and pions with momenta up to 400 MeV/c: the analysis of these data confirmed that the resolution on the deposited energy in the TPCs was of the order of 7%. When the first data of the T2K experiment were available, a first measurement of the electron neutrino component in the near detector has been done. To perform the analysis, a sample of neutrino interactions in ND280 was selected: this sample was mainly composed by muon neutrino interactions as the electron neutrino is expected to be 1 % of the total number of neutrinos in the beam. The selection of both, electron and muon neutrinos, allowed a first measurement of the electron neutrino component in the T2K beam
Scarpelli, Andrea. "Performances studies of the dual-phase Liquid Argon TPC for the DUNE experiment and analysis of the 4-tonne prototype detector data." Thesis, Université de Paris (2019-....), 2019. http://www.theses.fr/2019UNIP7159.
Full textThe 4 10 kt Liquid Argon Time Projection Chambers (LAr-TPCs) of the future DUNE experiment will enable precise measurements of the oscillation parameters and the discovery of CP violation for leptons, thanks to their excellent 3D imaging capabilities coupled with a high resolution calorimeter. One or more modules of the DUNE detector may exploit a dual phase (DP) LAr-TPC that, relying on the extraction of the charge produced in the liquid volume and its subsequent multiplication in argon gas, will increase the expected granularity and energy resolution. This thesis work present the simulation and reconstruction strategies of charged particles in a dual-phase LArTPC in the context of the DUNE experiment and its preliminary validation using cosmic ray data from the CERN 4 t demonstrator
Gizzarelli, Francesco. "Mesure du rapport des sections efficaces d'interaction des neutrinos sur les noyaux d'oxygène et de carbone, à partir des données du détecteur proche ND280 de l'expérience T2K." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS259.
Full textThe Standard Model of particle physics describes the interactions of subatomic particles through the strong, weak and electromagneticinteractions. However, it is known that this theory is not a complete description of the nature. Indeed the observation that neutrinos can change their flavor alongtheir propagation path (neutrino oscillation) proves that they actually have a mass. The work of this thesis has been performed in the T2K oscillation experiment: a long baseline experiment located in Japan. % detailed in Chapter ref{sec_t2k_res}.Using the data collected so far, T2K has been able to observe for the first time the $nu_{mu} rightarrow nu_e$ appearance and to give first results on the Charge-Paritysimmetry in neutrino oscillation. It provides also precise measurements of the oscillation parameters θ₁₃ , θ₂ ₃, Δm²₂ ₃.The precise measurement of oscillation parameters requires a good understanding of the detector and of the neutrino interaction model. This thesis is thus focused on boththese aspects: reduce the detector uncertainties and improve our knowledge of neutrino interactions with matter.The CEA Saclay group where I am involved, is in charge of the maintenance and operation of the Time Projection Chambers (TPCs) of the T2K near detector (ND280)which are used to identify and measure the kinematics of the charged particles produced in neutrino interactions.Part of my work was focused on the study of the TPC and in particular on the alignment of the MicroMegas modules instrumenting their readout planes.Indeed, misalignments between modules may cause a bias on the momentum measurement of the particles crossing the TPC.Neutrinos are studied through the observation of the final state of their interactions with matter. Therefore, the interactionmodels need to be extremely well understood to infer the neutrino properties correctly.Indeed current and next future oscillation experiments are approaching the phase of precise measurements of the mixing parameters becominglimited by our knowledge of neutrino interactions.The charged current quasi-elastic (CCQE) interaction is the most relevant process at T2K.This manuscript describes the measurement of CCQE cross-section ratio between oxygen and carbon nuclei. It can contribute to reduce the uncertainties on the oscillation analysis arisingfrom the different target between the near and far detector
Joshi, Shivam. "Characterization of resistive Micromegas for High Angle-Time Projection Chambers readout and preparation of neutrino physics analysis with upgraded near detector of T2K experiment." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP123.
Full textThe PhD work is in the field of Neutrino Physics as a part of the T2K experiment. The thesis is divided into two subjects- detector characterization and preparation of physics analysis. In the context of the upgrade of T2K near detector- ND280, a model was developed and utilized to characterize the charge spreading in novel resistive Micromegas (ERAM) detector. In addition, pad-by-pad gain and energy resolution was obtained for each ERAM for a complete characterization. The results directly led to the selection of specific ERAMs for installation at specific positions in the High Angle-Time Projection Chamber anode planes for charge readout. In total, 37 ERAMs were successfully characterized using X-ray data from a test bench at CERN. This information was also used as inputs for reconstruction. Improvement in statistics and detection efficiency of charged-current quasi-elastic events in high Q² (4-momentum transfer) region after the ND280 upgrade was studied. The question of- how effectively the high Q² uncertainties will be constrained after the ND280 upgrade by the 4 high Q² parameters in the neutrino-nucleus cross-section model was addressed using T2K re-weighting tools and the ND280 fitter- GUNDAM. An important source of the high Q² uncertainties is the axial-vector form factor model (dipole) used currently in the cross-section model. Some alternative form factor models that can better constrain these uncertainties were also studied. The effect of uncertainties in nucleon removal energy estimation on different variables (muon kinematics, neutrino energy, etc.) was studied. Binned splines were produced for the 4 removal energy parameters in the cross-section model in the context of Oscillation Analysis using data collected in 2024
Chaus, Andrii. "Searches for Dark Matter particules and development of a pixellized readout of the Time Projection Chamber for the International Linear Collider (ILC)." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112300.
Full textThe International Linear Collider (ILC) is planned to be the next major project in the High Energy Physics. ILC is proposed to have two detectors, namely International Large Detector (ILD), and Silicon Detector (SiD). This thesis is done in the framework of the ILD. One of the main components of the ILD detector is the Time Projection Chamber (TPC). This PhD thesis concentrates on the development of TPC readout, based on integration of the Micro-pattern gas detectors (Micromegas) and CMOS pixel chips ("Timepix"). This new type of device is named "InGrid". Main requirements for "InGrid" is to achieve sensitivity to single electrons and a very high spatial resolution (~30 μm). In TPC one reconstructs tracks using 2D-charge profile on the TPC endplate and the third coordinate is derived from the drift time information. In Saclay mini-TPC was built. Using this mini-TPC, several prototype "Ingrid" detectors have been tested in the course of this PhD. In addition, 8-chips system named “Octopuce” was built to develop track reconstruction algorithms. We have performed several measurements using laboratory radioactive source in Saclay. In addition, the large modules were tested at a Large TPC Prototype (LP) in a test beam area at DESY. Results with two different modules were presented. Obtained results well agreed with theoretical prediction. The existence of Dark Matter provides a strong indication for the appearance of new phenomena near the electroweak scale, and the popular WIMP hypothesis is out there to be tested. Since the couplings of WIMPs to different species of Standard Model particles are a priori unknown, the investigation of WIMP production in e+e- collisions is fundamentally complementary to production in pp collisions or direct detection of primordial WIMPs scattering on nucleons. In this work we investigate the discovery (or exclusion) reach of the ILC based on the production of a pair of WIMPs, which recoils against an energetic photon from initial state radiation. We show that the ILC can discover this signature even if annihilation to electrons provides only a small fraction of the total dark matter annihilation rate in the early universe. We translated the sensitivity into mass scales of various effective operators and showed that the WIMPs mass and couplings can be measured at the percent level in case of an observation. Furthermore, WIMPs studies on ILC are complementary to current LHC in the mono-X final states, because they test WIMP-lepton coupling. LHC studies WIMP-proton coupling at the scale of 1 TeV. ILC could reach limits up to 2 TeV on the contact interaction scale Λ for the vector operator by using an integrated luminosity at 500 fb⁻¹, at the center-of-mass √s = 500 GeV with unpolarized beams. Moreover, proper polarization configurations allows to improve sensitivity for the Dark Matter searches at the ILC, assuming WIMPs pair couple differently to electron and positron for different operators
Bienstock, Simon. "Étude de la violation de CP dans le secteur leptonique avec l'analyse combinée d'oscilaltions de neutrinos et d'anti-neutrinos dans l'expérience T2K." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS415.
Full textNeutrino physics is currently one of the most rich areas of high-energy physics, and neutrino oscillations in particular are opening the door to a new physics, beyond the standard model. In this context, the measurement of all mixing angles as non-zero offers the possibility of studying a possible violation of CP symmetry in the leptonic sector. The purpose of the T2K experiment, located in Japan, is to study these neutrino oscillations in the muon neutrino and anti-neutrino beam at J-PARC. The purpose of the T2K experiment, located in Japan, is to study these neutrino oscillations in the muon neutrino and anti-neutrino beam at J-PARC. Two channels thus studied: the disappearance of the muon (anti-) neutrinos of the beam and the appearance of (anti-) electronic neutrinos 295km further in the detector Super-Kamiokande. The measurement of the oscillation parameters involves a measurement of the number of events in the far detector, and requires a good modeling of the neutrino flux and interaction rate. These models are constrained before oscillation in a near detector, ND280, helping to greatly reduce the associated systematic uncertainties. T2K is the first experiment to show evidence of CP violation in the leptonic sector with a 2 sigma CL exclusion of CP conservation. In order to improve this constraint, a second phase of the experiment is proposed with an upgrade of the near detector in order to reduce the impact of systematic uncertainties on the cross section models
Agnes, Paolo. "Direct search for dark matter with the DarkSide experiment." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC279/document.
Full textA wide range of observational evidence suggests that the matter content of the Universe is dominated by a non-baryonic and non-luminous component: dark matter. One of the most favored candidate for dark matter is a big-bang relic population of Weakly Interacting Massive Particles (WIMPs). The DarkSide program aims to the direct detection of WIMPs with a dual-phase liquid argon TPC and a background free exposure. The first phase of the experiment, DarkSide-50, is running since Oct 2013 and has (46 ± 0.7) kg active mass. A first run, with an atmospheric argon fill (AAr), provided the most sensitive limit ever obtained by an argon-based experiment. The current run, with an underground argon fill (UAr, depleted in Ar-39), represents a milestone towards the construction of DarkSide-20k, a low-background dual-phase TPC with a fiducial mass of 20 t. This work is been mainly devoted to the description of G4DS, the DarkSide Monte Carlo simulation, and to its applications. G4DS is a GEANT4-based simulation, it provides the geometry description of each detector of the DarkSide program, it is tuned to reproduce the DarkSide-50 response at the percent level and incorporates a custom model for ionization and scintillation mechanisms in liquid argon, tuned on real data. The principal applications of the simulation include the estimate of the neutron and gamma backgrounds for DarkSide-50, the measurement of the Ar-39 depletion factor in UAr with respect to AAr and the design studies for DarkSide-20k
Hourlier, Adrien. "Background studies for electron anti-neutrino oscillations measurement at the Double Chooz experiment." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC192/document.
Full textDouble Chooz is a reactor anti-neutrino experiment which measures the θ13 mixing parameter in the neutrino oscillation phenomenon thanks to two identical underground detectors located at different distances from the two reactors of the Chooz nuclear power plant in the French Ardennes. The Far Detector started data taking in April 2011 and the Near Detector began operations in January 2015. This thesis presents an analysis of both the single- and twodetector phases. Neutrinos interact in Double Chooz through inverse β decay on protons, where positron and a neutron are emitted, creating two coincident signals. Analyses were performed for each detector on independent samples using the neutron capture on Gadolinium or on Hydrogen. A combined analysis, using both neutron captures is also presented. Backgrounds to the neutrino sample originate from the ambient radioactivity and the abundance of atmospheric muons (cosmogenic (β-n) emitters, fast neutron showers, and muons stopping and decaying inside the detector). This thesis focuses on developing techniques for measuring and reducing the Stopping Muon background. With colleagues from APC and MIT, a 60 litre neutron TPC was installed in both underground laboratories at Chooz. This low pressure He/CF4-based time projection chamber, called DCTPC, measures the flux, energy spectrum and direction of fast neutrons in both locations, with different overburdens (150 and 300 meters water equivalent for the Near and Far Laboratories respectively)
Mauss, Benoit. "Réactions élastiques et inélastiques résonantes pour la caractérisation expérimentale de la cible active ACTAR TPC." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC226/document.
Full textACTAR TPC (ACtive TARget and Time Projection Chamber) is a next generation active target that was designed and built at GANIL (Grand Accélérateur d'Ions Lourds). Active targets are gaseous targets in which the gas is also used to track charged particles following the principles of time projection chambers (TPC). The TPC of ACTAR has a segmented anode of 16384 2 mm side square pixels. The high density of pixels is processed using the GET (General Electronics for TPCs) electronic system. This system also digitizes the signals over a time interval, enabling a full 3D event reconstruction. An eight time smaller demonstrator was first built to verify the electronics operation and the mechanical design. ACTAR TPC's final design was based on results obtained with the demonstrator which was tested using 6Li, 24Mg and 58Ni beams. The commissioning of ACTAR TPC was then carried out for the case of resonant scattering on a proton target using 18O and 20Ne beams. A track reconstruction algorithm is used to extract the angles and energies of the ions involved in the reactions. Results are compared to previous data to determine the detection system performances. Comparing the commissioning data with R matrix calculations, excitation functions resolutions in different cases are obtained. The use of ACTAR TPC is validated for future experiments. Furthermore, alpha clustering was studied in 10B through the resonant scattering 6Li + 4He, carried out with the demonstrator. Two resonances at 8.58 MeV and 9.52 MeV are observed for the first time in elastic scattering with this reaction channel
Dastgheibi, Fard Ali. "Étude d’un détecteur sphérique gazeux pour la recherche d’événements rares à bas seuil en énergie." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112297/document.
Full textThe Spherical gaseous detector (or Spherical Proportional Counter, SPC) is a novel type of a particle detector, with a broad range of applications. Its main features in- clude a very low energy threshold which is independent of the volume (due to its very low capacitance), a good energy resolution, robustness and a single detection readout channel. SEDINE, a low background detector installed at the underground site of Laboratoire Souterrain de Modane is currently being operated and aims at measuring events at a very low energy threshold, around 40 eV. The sensitivity for the rare events detection at low energy is correlated to the detector background and to the decreasing the level of energy threshold, which was the main point of this thesis. A major effort has been devoted to the operating of the experimental detector. Several detection parameters were optimized: the electric field homogeneity in the sphere, keeping clear of sparks, the electronic noise level and the leak rate of the detector. The detector is optimized for operation with a high pressure stable gain. The modification of the shield, cleanings of the detector and the addition of an anti-Radon tent have significantly reduced the background of SEDINE. Progress has increased the sensitivity of the detector at low energy up to a value comparable to the results other underground research experiences for the low mass WIMPs. We will present the results with a measured background in the region of keV, which has allowed us to show a competitive figure of exclusion for the production of light dark matter
Vandebrouck, Marine. "Première mesure des résonances géantes isoscalaires dans un noyau exotique riche en neutrons : le 68Ni avec la cible active Maya." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00872712.
Full textSantamaria, Clémentine. "Quest for new nuclear magic numbers with MINOS." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112153/document.
Full textThe MINOS device has been developed until mid-2013 for in-beam γ spectroscopy of very exotic nuclei from proton knockout reactions. It is composed of a thick liquid hydrogen target to achieve higher luminosities and a Time Projection Chamber (TPC) to reconstruct the vertex position and compensate for the thick target effect on the Doppler correction.The Time Projection Chamber has been developed with the expertise of CEA-IRFU in gas detectors and Micromegas detectors. At first, different solutions for the TPC were tested in a test chamber with an α source and cosmic-ray measurements. Cosmic rays were detected for the first time using the test chamber in early 2013 and validated the use of a Micromegas detection plane. The first TPC prototype was finished in May 2013, and we used a cosmic-ray bench to estimate the effiiciency of the TPC. The MINOS device was then shipped to Japan and an in-beam performance test was performed at the HIMAC medical facility (Chiba, Japan) with two thin targets instead of the thick hydrogen target to validate the tracking algorithm and the vertex position resolution. A tracking algorithm for the offline analysis based on the Hough transform has been developed, tested with the data, and compared with simulations.The first physics campaign using MINOS took place in May 2014 with SEASTAR. It focused on the first spectroscopy of ⁶ ⁶ Cr, ⁷⁰,⁷²Fe, and ⁷⁸Ni. The analysis of the ⁶⁶Cr spectroscopy revealed two transitions, assigned to the two first excited states. An interpretation with shell model calculations shows that the maximum of quadrupole collectivity occurs at N=40 along the Cr isotopic chain.⁶⁶Cr is still placed in the Island of Inversion region of N=40 and the shell model calculations as well as comparison with HFB-based calculations suggest an extension of this Island of Inversion towards N=50 below ⁷⁸Ni. The analysis of ⁷⁰,⁷²Fe performed by C. Louchart (TU Darmstadt, Germany) reveals the same trend as for Cr isotopes, with a maximum of deformation at N=42. The full data set and our shell-model interpretation suggests a large collectivity for neutron-rich Cr and Fe, possibly up to N=50, questioning the robustness of the N=50 shell closure below ⁷⁸Ni