168670 20260213191049.0 doi 10.1088/1475-7516/2009/02/008 sideral 63699 ART-2009-63699 eng Arik, E. Probing eV-Scale Axions with CAST 2009 We have searched for solar axions or other pseudoscalar particles that couple to two photons by using the CERN Axion Solar Telescope (CAST) setup. Whereas we previously have reported results from CAST with evacuated magnet bores (Phase I), setting limits on lower mass axions, here we report results from CAST where the magnet bores were filled with 4He gas (Phase II) of variable pressure. The introduction of gas generates a refractive photon mass mγ, thereby achieving the maximum possible conversion rate for those axion masses ma that match mγ. With 160 different pressure settings we have scanned ma up to about 0.4 eV, taking approximately 2 h of data for each setting. 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 gaγ≲2.2 × 10−10 GeV−1 at 95% CL for ma≲0.4 eV, the exact result depending on the pressure setting. The excluded parameter range covers realistic axion models with a Peccei-Quinn scale in the neighborhood of fa ∼ 107 GeV. Currently in the second part of CAST Phase II, we are searching for axions with masses up to about 1.2 eV using 3He as a buffer gas. info:eu-repo/semantics/closedAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 6.502 2009 PHYSICS, PARTICLES & FIELDS 3 / 27 = 0.111 2009 Q1 T1 ASTRONOMY & ASTROPHYSICS 6 / 52 = 0.115 2009 Q1 T1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Aune, S. Autiero, D. Barth, K. Belov, A. Beltran, B. Borghi, S. Bourlis, G. Boydag, F. S. Braeuninger, H. Carmona, J. M. Cebrian, S. Universidad de Zaragoza (orcid)0000-0002-6948-5101 Cetin, S. A. Collar, J. I. Dafni, T. Universidad de Zaragoza (orcid)0000-0002-8921-910X Davenport, M. Di Lella, L. Dogan, O. B. Eleftheriadis, C. Elias, N. Fanourakis, G. Ferrer-Ribas, E. Fischer, H. Friedrich, P. Franz, J. Galan, J. Geralis, T. Giomataris, I. Gninenko, S. Gomez, H. Universidad de Zaragoza (orcid)0000-0002-1770-8940 Hartmann, R. Hasinoff, M. Heinsius, F. H. Hikmet, I. Hoffmann, D. H. H. Irastorza, I. G. Universidad de Zaragoza (orcid)0000-0003-1163-1687 Jacoby, J. Jakovcic, K. Kang, D. Koenigsmann, K. Kotthaus, R. Krcmar, M. Kousouris, K. Kuster, M. Lakic, B. Lasseur, C. Liolios, A. Ljubicic, A. Lutz, G. Luzon, G. Universidad de Zaragoza (orcid)0000-0002-5352-1884 Miller, D. Morales, J. Universidad de Zaragoza Niinikoski, T. Nordt, A. Ortiz, A. Papaevangelou, T. Pivovaroff, M. J. Placci, A. Raffelt, G. Riege, H. Rodriguez, A. Ruz, J. Universidad de Zaragoza (orcid)0000-0002-3253-7027 Savvidis, I. Semertzidis, Y. Serpico, P. Soufli, R. Stewart, L. Van Bibber, K. Villar, J. Universidad de Zaragoza (orcid)0000-0003-0228-7589 Vogel, J. Walckiers, L. Zioutas, K. 2004 390 Universidad de Zaragoza Dpto. Física Teórica Área Física Atóm.Molec.y Nucl. 2, 008 (2009), 1-15 J. Cosmol. Astropart. Phys. Journal of Cosmology and Astroparticle Physics 1475-7516 927629 http://zaguan.unizar.es/record/168670/files/texto_completo.pdf Versión publicada 1994803 http://zaguan.unizar.es/record/168670/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:168670 articulos driver 2026-02-13-18:28:07 ARTICLE