TY - JOUR
T1 - Construction on vacuum-compatible straw tracker for COMET Phase-I
AU - Nishiguchi, H.
AU - Evtoukhovitch, P.
AU - Fujii, Y.
AU - Hamada, E.
AU - Kamei, N.
AU - Mihara, S.
AU - Moiseenko, A.
AU - Noguchi, K.
AU - Oishi, K.
AU - Suzuki, J.
AU - Tojo, J.
AU - Tsamalaidze, Z.
AU - Tsverava, N.
AU - Ueno, K.
AU - Volkov, A.
PY - 2019/9/19
Y1 - 2019/9/19
N2 - The COMET experiment at J-PARC aims to search for a lepton-flavour violating process of muon to electron conversion in a muonic atom, μ-e conversion, with a branching-ratio sensitivity of better than 10−16, 4 orders of magnitude better than the present limit, in order to explore the parameter region predicted by most of well-motivated theoretical models beyond the Standard Model. The need for such an excellent sensitivity places several stringent requirements on the detector; (i) good momentum resolution, <2%, for 100 MeV/c electron, which is primarily limited by multiple scattering effect for this momentum region, and (ii) high rate capability, up to 5×109μ−/s muon beam by J-PARC. In order fulfil such requirements, we decided to develop the straw-base planar tracker which is operational in vacuum and made of an extremely light material. The COMET straw tracker consists of 10 mm diameter straw tube, longer than 1 m length, with 20μm-thick Mylar foil and 70 nm-thick aluminium cathode. Recently, two big milestones, detector-performance verification by the full-scale prototype with 100 MeV/c electron beam, and start the assembly of final straw tracker for COMET Phase-I, were achieved. In this article, details of these two big milestones are provided. In addition, some prospects on the straw tracker development towards the COMET Phase-II are also given.
AB - The COMET experiment at J-PARC aims to search for a lepton-flavour violating process of muon to electron conversion in a muonic atom, μ-e conversion, with a branching-ratio sensitivity of better than 10−16, 4 orders of magnitude better than the present limit, in order to explore the parameter region predicted by most of well-motivated theoretical models beyond the Standard Model. The need for such an excellent sensitivity places several stringent requirements on the detector; (i) good momentum resolution, <2%, for 100 MeV/c electron, which is primarily limited by multiple scattering effect for this momentum region, and (ii) high rate capability, up to 5×109μ−/s muon beam by J-PARC. In order fulfil such requirements, we decided to develop the straw-base planar tracker which is operational in vacuum and made of an extremely light material. The COMET straw tracker consists of 10 mm diameter straw tube, longer than 1 m length, with 20μm-thick Mylar foil and 70 nm-thick aluminium cathode. Recently, two big milestones, detector-performance verification by the full-scale prototype with 100 MeV/c electron beam, and start the assembly of final straw tracker for COMET Phase-I, were achieved. In this article, details of these two big milestones are provided. In addition, some prospects on the straw tracker development towards the COMET Phase-II are also given.
KW - COMET
KW - Gaseous detector
KW - J-PARC
KW - Lepton Flavour Violation
KW - Muon experiment
KW - Straw tracker
UR - http://www.scopus.com/inward/record.url?scp=85072563408&partnerID=8YFLogxK
U2 - 10.1016/j.nima.2019.162800
DO - 10.1016/j.nima.2019.162800
M3 - Article
AN - SCOPUS:85072563408
JO - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment
SN - 0168-9002
M1 - 162800
ER -