First Search for Bosonic Superweakly Interacting Massive Particles with Masses up to <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mn>1</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>MeV</mml:mi><mml:mo>/</mml:mo><mml:msup><mml:mrow><mml:mi>c</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math> with GERDA
M. Agostini, A. M. Bakalyarov, M. Balata, И. Р. Барабанов, L. Baudis, C. Bauer, E. Bellotti, S. Belogurov, A. Bettini, L. Bezrukov, D. Borowicz, E. Bossio, V. Bothe, V. Brudanin, R. Brugnera, A. Caldwell, C. Cattadori, A. Chernogorov, T. Comellato, V. D’Andrea, É. V. Demidova, N. Di Marco, E. Doroshkevich, V. Egorov, F. Fischer, M. Fomina, A. M. Gangapshev, A. Garfagnini, C. Gooch, P. Grabmayr, V. Gurentsov, K. Gusev, J. Hakenmüller, S. Hemmer, R. Hiller, W. Hofmann, M. Hult, Л. В. Инжечик, J. Janicskó Csáthy, J. Jochum, M. Junker, V. V. Kazalov, Y. Kermaïdic, H. Khushbakht, T. Kihm, I. V. Kirpichnikov, A. Klimenko, R. Kneißl, K.T. Knöpfle, O. Kochetov, В. Н. Корноухов, P. Krause, V. V. Kuzminov, M. Laubenstein, A. Lazzaro, M. Lindner, I. Lippi, A. Lubashevskiy, Б. Лубсандоржиев, G. Lutter, C. Macolino, B. Majorovits, W. Maneschg, M. Miloradovic, R. Mingazheva, M. Misiaszek, P. Moseev, I. Nemchenok, K. Panas, L. Pandola, K. Pelczar, L. Pertoldi, P. Piseri, A. Pullia, C. Ransom, L. Rauscher, S. Riboldi, N. Rumyantseva, C. Sada, F. Salamida, S. Schönert, J. Schreiner, M. Schütt, A.-K. Schütz, O. Schulz, M. Schwarz, B. Schwingenheuer, O. Selivanenko, E. Shevchik, M. Shirchenko, H. Simgen, A. Smolnikov, D. Stukov, A. A. Vasenko, A. Veresnikova, C. Vignoli, K. von Sturm, T. Wester, Christoph Wiesinger, M. Wójcik
Abstract
We present the first search for bosonic superweakly interacting massive particles (super-WIMPs) as keV-scale dark matter candidates performed with the GERDA experiment. GERDA is a neutrinoless double-$\ensuremath{\beta}$ decay experiment which operates high-purity germanium detectors enriched in $^{76}\mathrm{Ge}$ in an ultralow background environment at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy. Searches were performed for pseudoscalar and vector particles in the mass region from $60\text{ }\text{ }\mathrm{keV}/{c}^{2}$ to $1\text{ }\text{ }\mathrm{MeV}/{c}^{2}$. No evidence for a dark matter signal was observed, and the most stringent constraints on the couplings of super-WIMPs with masses above $120\text{ }\text{ }\mathrm{keV}/{c}^{2}$ have been set. As an example, at a mass of $150\text{ }\text{ }\mathrm{keV}/{c}^{2}$ the most stringent direct limits on the dimensionless couplings of axionlike particles and dark photons to electrons of ${g}_{ae}<3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ and ${\ensuremath{\alpha}}^{\ensuremath{'}}/\ensuremath{\alpha}<6.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}24}$ at 90% credible interval, respectively, were obtained.