A high efficiency photon veto for the Light Dark Matter eXperiment
Fixed-target experiments using primary electron beams can be powerful discovery tools for light dark matter in the sub-GeV mass range. The Light Dark Matter eXperiment (LDMX) is designed to measure missing momentum in high-rate electron fixed-target reactions with beam energies of 4 GeV to 16 GeV. A prerequisite for achieving several important sensitivity milestones is the capability to efficiently reject backgrounds associated with few-GeV bremsstrahlung, by twelve orders of magnitude, while maintaining high efficiency for signal. The primary challenge arises from events with photo-nuclear reactions faking the missing-momentum property of a dark matter signal. We present a methodology developed for the LDMX detector concept that is capable of the required rejection. By employing a detailed GEANT4-based model of the detector response, we demonstrate that the sampling calorimetry proposed for LDMX can achieve better than $$10^{-13}$$ rejection of few-GeV photons. This suggests that the luminosity-limited sensitivity of LDMX can be realized at 4 GeV and higher beam energies.
- Research Organization:
- SLAC National Accelerator Lab., Menlo Park, CA (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), High Energy Physics (HEP)
- Contributing Organization:
- The LDMX collaboration
- Grant/Contract Number:
- AC02-76SF00515; AC02-07CH11359
- OSTI ID:
- 1608809
- Alternate ID(s):
- OSTI ID: 1614743
- Report Number(s):
- FERMILAB-PUB-19-620-SCD; SLAC-PUB-17495; arXiv:1912.05535; TRN: US2105104
- Journal Information:
- Journal of High Energy Physics (Online), Vol. 2020, Issue 4; ISSN 1029-8479
- Publisher:
- Springer BerlinCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Current Status and Future Prospects for the Light Dark Matter eXperiment
Light Dark Matter eXperiment (LDMX)