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arXiv · 2308.15173

Photon-rejection Power of the Light Dark Matter eXperiment in an 8 GeV Beam

Abstract

The Light Dark Matter eXperiment (LDMX) is an electron-beam fixed-target experiment designed to achieve comprehensive model independent sensitivity to dark matter particles in the sub-GeV mass region. An upgrade to the LCLS-II accelerator will increase the beam energy available to LDMX from 4 to 8 GeV. Using detailed GEANT4-based simulations, we investigate the effect of the increased beam energy on the capabilities to separate signal and background, and demonstrate that the veto methodology developed for 4 GeV successfully rejects photon-induced backgrounds for at least $2\times10^{14}$ electrons on target at 8 GeV.

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Torsten Åkesson, Cameron Bravo, Liam Brennan, Lene Kristian Bryngemark, Pierfrancesco Butti, E. Craig Dukes, Valentina Dutta, Bertrand Echenard, Thomas Eichlersmith, Jonathan Eisch, Einar Elén, Ralf Ehrlich, Cooper Froemming, Andrew Furmanski, Niramay Gogate, Chiara Grieco, Craig Group, Hannah Herde, Christian Herwig, David G. Hitlin, Tyler Horoho, Joseph Incandela, Wesley Ketchum, Gordan Krnjaic, Amina Li, Jeremiah Mans, Phillip Masterson, Sophie Middleton, Omar Moreno, Geoffrey Mullier, Joseph Muse, Timothy Nelson, Rory O'Dwyer, Leo Östman, James Oyang, Jessica Pascadlo, Ruth Pöttgen, Luis G. Sarmiento, Philip Schuster, Matthew Solt, Cristina Mantilla Suarez, Lauren Tompkins, Natalia Toro, Nhan Tran, Erik Wallin, Andrew Whitbeck, Danyi Zhang. 2023-08-29. Photon-rejection Power of the Light Dark Matter eXperiment in an 8 GeV Beam. https://arxiv.org/abs/2308.15173

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