1307.1985 (M. Arik et al.)

CAST solar axion search with 3^He buffer gas: Closing the hot dark
matter gap    [PDF]

M. Arik, S. Aune, K. Barth, A. Belov, S. Borghi, H. Brauninger, G. Cantatore, J. M. Carmona, S. A. Cetin, J. I. Collar, E. Da Riva, T. Dafni, M. Davenport, C. Eleftheriadis, N. Elias, G. Fanourakis, E. Ferrer-Ribas, P. Friedrich, J. Galan, J. A. Garcia, A. Gardikiotis, J. G. Garza, E. N. Gazis, T. Geralis, E. Georgiopoulou, I. Giomataris, S. Gninenko, H. Gomez, M. Gomez Marzoa, E. Gruber, T. Guthorl, R. Hartmann, S. Hauf, F. Haug, M. D. Hasinoff, D. H. H. Hoffmann, F. J. Iguaz, I. G. Irastorza, J. Jacoby, K. Jakovcic, M. Karuza, K. Konigsmann, R. Kotthaus, M. Krcmar, M. Kuster, B. Lakic, P. M. Lang, J. M. Laurent, A. Liolios, A. Ljubicic, V. Lozza, G. Luzon, S. Neff, T. Niinikoski, A. Nordt, T. Papaevangelou, M. J. Pivovaroff, G. Raffelt, H. Riege, A. Rodriguez, M. Rosu, J. Ruz, I. Savvidis, I. Shilon, P. S. Silva, S. K. Solanki, L. Stewart, A. Tomas, M. Tsagri, K. van Bibber, T. Vafeiadis, J. Villar, J. K. Vogel, S. C. Yildiz, K. Zioutas

The CERN Axion Solar Telescope (CAST) has finished its search for solar axions with 3^He buffer gas, covering the search range 0.64 eV < m_a <1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence of excess X-rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of g_ag < 3.3 x 10^{-10} GeV^{-1} at 95% CL, with the exact value depending on the pressure setting. Future direct solar axion searches will focus on increasing the sensitivity to smaller values of g_a, for example by the currently discussed next generation helioscope IAXO.

View original: http://arxiv.org/abs/1307.1985