Field of Interest:hep-ex
Experiments:CLAS12
Deadline: 2017-02-28
Region: Europe
Job description:
The study of the inner structure of the nucleon is one of the main challenges in hadronic physics nowadays. Our team at IPN Orsay carries out experiments at Jefferson Lab (JLab - Virginia, USA),focusing in particular on measurements of exclusive electroproduction reactions, which allow to access the Generalized Parton Distributions (GPDs) of the nucleon. The formalism of GPDs provides a universal description of the structure of the nucleon in terms of its constituents, the quarks and gluons: their spatial distribution, their contribution to the momentum and spin of the nucleon, etc.
Our team has lead a program, very fruitful in terms of results and having a strong impact, of measurements of GPDs at JLab with a 6-GeV electron beam. This program is continuing with the 12-GeV upgrade of JLab, which will increase the kinematic coverage for the study of GPDs. IPN Orsay has contributed to the JLab upgrade by constructing, and recently completing, a neutron detector (Central Neutron Detector, CND) for the Hall-B CLAS12 spectrometer. The CND will allow us to measure neutron GPDs and thus to extract the contributions of the various quark flavors to the GPDs. The installation of the CND in CLAS12 is scheduled for the spring of 2017. The first CLAS12 data taking, on an unpolarized proton target, will follow, and the student will have the unique opportunity to take an active part in it. These data will allow the student to measure the CND neutron-detection efficiency. She/he will then perform a full data analysis to extract physics observables of interest for the CLAS12 GPD program, such as beam-spin asymmetries for Deeply Virtual Compton Scattering reaction (DVCS, ep -> e'p'gamma), or for Time-like Compton Scattering (TCS, gamma p -> gamma*p'), or cross sections for the exclusive electroproduction of mesons.
Several trips to Jefferson Lab will be required, during the data taking stages. A background in high-energy or nuclear physics is required, along with a good knowledge of the English language and adequate computing skills.
To apply online: http://www.adum.fr/as/ed/voirpropositionT.pl?site=PSaclay&matricule_prop=13026
More Information:https://userweb.jlab.org/~silvia/these_cnd_clas12_2017.pdf
Experiments:CLAS12
Deadline: 2017-02-28
Region: Europe
Job description:
The study of the inner structure of the nucleon is one of the main challenges in hadronic physics nowadays. Our team at IPN Orsay carries out experiments at Jefferson Lab (JLab - Virginia, USA),focusing in particular on measurements of exclusive electroproduction reactions, which allow to access the Generalized Parton Distributions (GPDs) of the nucleon. The formalism of GPDs provides a universal description of the structure of the nucleon in terms of its constituents, the quarks and gluons: their spatial distribution, their contribution to the momentum and spin of the nucleon, etc.
Our team has lead a program, very fruitful in terms of results and having a strong impact, of measurements of GPDs at JLab with a 6-GeV electron beam. This program is continuing with the 12-GeV upgrade of JLab, which will increase the kinematic coverage for the study of GPDs. IPN Orsay has contributed to the JLab upgrade by constructing, and recently completing, a neutron detector (Central Neutron Detector, CND) for the Hall-B CLAS12 spectrometer. The CND will allow us to measure neutron GPDs and thus to extract the contributions of the various quark flavors to the GPDs. The installation of the CND in CLAS12 is scheduled for the spring of 2017. The first CLAS12 data taking, on an unpolarized proton target, will follow, and the student will have the unique opportunity to take an active part in it. These data will allow the student to measure the CND neutron-detection efficiency. She/he will then perform a full data analysis to extract physics observables of interest for the CLAS12 GPD program, such as beam-spin asymmetries for Deeply Virtual Compton Scattering reaction (DVCS, ep -> e'p'gamma), or for Time-like Compton Scattering (TCS, gamma p -> gamma*p'), or cross sections for the exclusive electroproduction of mesons.
Several trips to Jefferson Lab will be required, during the data taking stages. A background in high-energy or nuclear physics is required, along with a good knowledge of the English language and adequate computing skills.
To apply online: http://www.adum.fr/as/ed/voirpropositionT.pl?site=PSaclay&matricule_prop=13026
More Information:https://userweb.jlab.org/~silvia/these_cnd_clas12_2017.pdf