Background Rejection in the DMTPC Dark Matter Search Using Charge Signals

Abstract

The Dark Matter Time Projection Chamber (DMTPC) collaboration is developing low-pressure gas TPC detectors for measuring WIMP-nucleon interactions. Optical readout with CCD cameras allows for the detection for the daily modulation in the direction of the dark matter wind, while several charge readout channels allow for the measurement of additional recoil properties. In this article, we show that the addition of the charge readout analysis to the CCD allows us too obtain a statistics-limited 90% C.L. upper limit on the $e^{-}$ rejection factor of $5.6\times 10^{-6}$ for recoils with energies between 40 and 200 keV${}_{\mathrm{ee}}$. In addition, requiring coincidence between charge signals and light in the CCD reduces CCD-specific backgrounds by more than two orders of magnitude.

8 pages, 6 figures. For proceedings of DPF 2011 conference

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Cited by in corpus (9)

• A review of the discovery reach of directional Dark Matter detection
• Complementarity of dark matter detectors in light of the neutrino background
• Readout technologies for directional WIMP Dark Matter detection
• Measurement of the directional sensitivity of DMTPC detectors
• WIMP detection and slow ion dynamics in carbon nanotube arrays
• Low energy electron/recoil discrimination for directional Dark Matter detection
• In situ measurement of the electron drift velocity for upcoming directional Dark Matter detectors
• Overview of Non-Liquid Noble Direct Detection Dark Matter Experiments
• Observables for Recoil Identification in High-Definition Gas Time Projection Chambers