Construction on vacuum-compatible straw tracker for COMET Phase-I

H. Nishiguchi, P. Evtoukhovitch, Y. Fujii, E. Hamada, N. Kamei, S. Mihara, A. Moiseenko, K. Noguchi, K. Oishi, J. Suzuki, J. Tojo, Z. Tsamalaidze, N. Tsverava, K. Ueno, A. Volkov

Research output: Contribution to journalArticleResearchpeer-review

Abstract

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.

Original languageEnglish
Article number162800
Number of pages4
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
DOIs
Publication statusAccepted/In press - 19 Sep 2019

Keywords

  • COMET
  • Gaseous detector
  • J-PARC
  • Lepton Flavour Violation
  • Muon experiment
  • Straw tracker

Cite this

Nishiguchi, H., Evtoukhovitch, P., Fujii, Y., Hamada, E., Kamei, N., Mihara, S., Moiseenko, A., Noguchi, K., Oishi, K., Suzuki, J., Tojo, J., Tsamalaidze, Z., Tsverava, N., Ueno, K., & Volkov, A. (Accepted/In press). Construction on vacuum-compatible straw tracker for COMET Phase-I. Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, [162800]. https://doi.org/10.1016/j.nima.2019.162800