The MoEDAL Apparatus for Penetrating Particles (MAPP) at the LHC - Part (2)

点击翻译按钮获取中文摘要

The MoEDAL (Monopole and Exotics Detector at the LHC) is the 1st  "dedicated search experiment" to be deployed at  the LHC. It is designed to search for the highly ionizing  particle (HIP) avatars of new physics in a complementary way to the main LHC detectors, ATLAS and CMS. The MoEDAL experiment, led by the MoEDAL-Alberta group, is carried out by a international collaboration of 70 physicists. It is partially supported by an NSERC Discovery grant. MoEDAL started to take data in 2015 and has since then established the world's most stringent limits on:  multiply charged magnetic monopole production. It is also the first experiment to place limits on:  the direct production of spin1 monopoles; dyons, particles with electric and magnetic charge; and,  monopoles produced  in heavy-ion collisions via the Schwinger mechanism.  MoEDAL was also the first experiment to  place limits on monopole production via photon fusion at the LHC. MoEDAL papers reporting the world's best experimental limits  on massive electrically charged HIPs, are in the process of being submitted. MoEDAL will be reinstalled to take data at LHC's Run-3 starting in 2022 with the addition of a new sub-detector called MAPP (MoEDAL Apparatus for Penetrating Particles). MAPP's purpose is to expand MoEDAL's  physics reach to include the search for Feebly Interacting Particles, such as  mini-charged particles (mCP) with charge as low as 0.001e, where e is the electron charge. The funding for the construction of the MAPP-mcP detector was largely provided by a Category-2 RTI grant awarded in 2020.  MAPP-mCP consists of 4 collinear sections with cross-sectional area 1 sqm. Each section is comprised of 100 (10cm x 10cm x 75cm) scintillator bars readout by a fast, low noise PMT and specialized fast electronics. Thus, each through going particle will encounter 3m of scintillator, readout by 4 PMTs in coincidence. MAPP is protected from cosmic rays and SM particles from IP8, by: 100m rock overburden; at least 30 m of intervening rock; and, an active veto system. The MAPP-mCP detector will greatly extend the LHC's sensitivity to fractional charge which currently lies at only ~1/3e. This request has two parts. The 1st  part is for additional funding to finish the MAPP-mCP detector. This is required because our  Chinese PMT supplier (HZK) ceased trading in 2021  before all 400 PMTs were delivered, due to financial problems arising from the   Covid-19 pandemic. As a result we have to purchase the last 100 PMTs from Hamamatsu as a much higher price. We are asking for the difference is the cost between 100 HZK PMTs, already funded,  and 100 equivalent  Hamamatsu PMTs. The 2nd part of the request,  is for  an outrigger scintillator detector to improve the MAPP-mQP's acceptance for higher mass milli-charged particles. Here the funds are needed to provide additional scintillator material to add to a contribution of scintillator from the EXO-200 collaboration, in order to complete the detector.