Search for low-mass dark matter via bremsstrahlung radiation and the Migdal effect in SuperCDMS
M. F. Albakry, I. Alkhatib, David Alonso-González, D. W. P. Amaral, T. Aralis, T. Aramaki, I. J. Arnquist, I. Ataee Langroudy, E. Azadbakht, S. Banik, C. Bathurst, R. Bhattacharyya, P. L. Brink, R. Bunker, B. Cabrera, R. Calkins, R. A. Cameron, C. Cartaro, D. G. Cerdeño, Y. -Y. Chang, M. Chaudhuri, R. Chen, N. Chott, J. Cooley, H. Coombes, Jacqueline Corbett, P. Cushman, S. Das, F. De Brienne, Martín de los Rios, S. Dharani, M. L. di Vacri, M. D. Diamond, M. Elwan, E. Fascione, E. Figueroa‐Feliciano, C. W. Fink, K. Fouts, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, S. R. Golwala, J. Hall, N. Hassan, B. A. Hines, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, Vipul Kashyap, M. H. Kelsey, A. Kubik, N. A. Kurinsky, M. Lee, A. Li, M. Litke, J. Liu, Y. Liu, B. Loer, E. Lopez Asamar, P. Lukens, D. B. MacFarlane, R. Mahapatra, J. S. Mammo, N. Mast, A. Mayer, H. Meyer Zu Theenhausen, Eva Michaud, E. Michielin, N. Mirabolfathi, B. Mohanty, J. K. Nelson, H. Neog, V. Novati, J. L. Orrell, M. D. Osborne, S. M. Oser, W. A. Page, L. Pandey, S. Pandey, R. Partridge, D. S. Pedreros, L. Perna, R. Podviianiuk, F. Ponce, S. Poudel, A. Pradeep, M. Pyle, W. Rau, E. Reid, R. Ren, T. Reynolds, Ann Roberts, A. E. Robinson, T. Saab, D. Sadek, B. Sadoulet
Abstract
We present a new analysis of previously published SuperCDMS data using a profile likelihood framework to search for sub-GeV dark matter (DM) particles through two inelastic scattering channels: bremsstrahlung radiation and the Migdal effect. By considering these possible inelastic scattering channels, experimental sensitivity can be extended to DM masses that are undetectable through the DM-nucleon elastic scattering channel, given the energy threshold of current experiments. We exclude DM masses down to $220\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ at $2.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}30}\text{ }\text{ }{\mathrm{cm}}^{2}$ via the bremsstrahlung channel. The Migdal channel search provides overall considerably more stringent limits and excludes DM masses down to $30\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ at $5.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}30}\text{ }\text{ }{\mathrm{cm}}^{2}$.