arXiv : First Results on the Search for Chameleons with the KWISP Detector at CAST

Arguedas Cuendis, S.; Karuza*, M.; Fischer*, H.; Bräuninger, H.; Funk, W.; Dermenev, A.; Ozbey, A.; Gninenko, S.; Ruiz Chóliz, E.; Castel, J.F.; Schmidt, S.; Lakić, B.; Dafni, T.; Vafeiadis, T.; Irastorza, I.G.; Pivovaroff, M.J.; Schumann, M.; Carmona, J.M.; Maroudas, M.; Neff, S.; Davenport, M.; Bayirli, A.; Laurent, J.M.; Desch, K.; Stewart, L.; Ortega, I.; Semertzidis, Y.K.; Yildiz, S.C.; Gardikiotis, A.; Hasinoff, M.D.; Tsagris, I.; Ruz, J.; Vogel, J.K.; Cetin, S.A.; Solanki, S.K.; Miceli, L.; Garć ia, J.A.; Cantatore, G.; Zioutas, K.; Belov, A.; Rosu, M.; Krieger, C.; Baier, J.; Garza, J.G.; Vretenar, M.; Iguaz, F.J.; Jakovčí c, K.; Döbrich, B.; Baum, S.; Kaminski, J.; Barth, K.; Luzón, G.; Hoffmann, D.H.H.

doi:10.1016/j.dark.2019.100367

Article
Report number	arXiv:1906.01084
Title	First Results on the Search for Chameleons with the KWISP Detector at CAST
Author(s)	Arguedas Cuendis, S. (CERN) ; Baier, J. (Freiburg U.) ; Barth, K. (CERN) ; Baum, S. (Royal Inst. Tech., Stockholm ; Stockholm U., OKC ; Nordita) ; Bayirli, A. (Istanbul U.) ; Belov, A. (Moscow, INR) ; Bräuninger, H. (Garching, Max Planck Inst., MPE) ; Cantatore, G. (INFN, Trieste ; Trieste U.) ; Carmona, J.M. (Zaragoza U.) ; Castel, J.F. (Zaragoza U.) ; Cetin, S.A. (Istanbul U.) ; Dafni, T. (Zaragoza U.) ; Davenport, M. (CERN) ; Dermenev, A. (Moscow, INR) ; Desch, K. (Bonn U.) ; Döbrich, B. (CERN) ; Fischer, H. (Freiburg U.) ; Funk, W. (CERN) ; Garć ia, J.A. (Zaragoza U.) ; Gardikiotis, A. (Patras U.) ; Garza, J.G. (Zaragoza U.) ; Gninenko, S. (Moscow, INR) ; Hasinoff, M.D. (British Columbia U.) ; Hoffmann, D.H.H. (Xian Jiaotong U.) ; Iguaz, F.J. (Zaragoza U.) ; Irastorza, I.G. (Zaragoza U.) ; Jakovčí c, K. (Boskovic Inst., Zagreb) ; Kaminski, J. (Bonn U.) ; Karuza, M. (Rijeka U. ; LSU, CAMD ; INFN, Trieste) ; Krieger, C. (Bonn U.) ; Lakić, B. (Boskovic Inst., Zagreb) ; Laurent, J.M. (CERN) ; Luzón, G. (Zaragoza U.) ; Maroudas, M. (Patras U.) ; Miceli, L. (IBS, Daejeon, CAPP) ; Neff, S. (Bogazici U.) ; Ortega, I. (Zaragoza U. ; CERN) ; Ozbey, A. (Istanbul U.) ; Pivovaroff, M.J. (LLNL, Livermore) ; Rosu, M. (ELI-NP, Bucharest) ; Ruz, J. (LLNL, Livermore) ; Ruiz Chóliz, E. (Zaragoza U.) ; Schmidt, S. (Bonn U.) ; Schumann, M. (Freiburg U.) ; Semertzidis, Y.K. (IBS, Daejeon, CAPP ; KAIST, Taejon) ; Solanki, S.K. (Lindau, Max Planck Inst.) ; Stewart, L. (CERN) ; Tsagris, I. (Patras U.) ; Vafeiadis, T. (CERN) ; Vogel, J.K. (LLNL, Livermore) ; Vretenar, M. (Rijeka U.) ; Yildiz, S.C. (Istanbul U.) ; Zioutas, K. (Patras U. ; CERN)
Publication	2019-12
Imprint	2019-06-03
Number of pages	21
Note	21 pages, 12 figures
In:	Phys. Dark Univ. 26 (2019) 100367
DOI	10.1016/j.dark.2019.100367
Subject category	physics.ins-det ; Detectors and Experimental Techniques ; astro-ph.SR ; Astrophysics and Astronomy ; astro-ph.CO ; Astrophysics and Astronomy ; hep-ex ; Particle Physics - Experiment
Accelerator/Facility, Experiment	CAST
Abstract	We report on a first measurement with a sensitive opto-mechanical force sensor designed for the direct detection of coupling of real chameleons to matter. These dark energy candidates could be produced in the Sun and stream unimpeded to Earth. The KWISP detector installed on the CAST axion search experiment at CERN looks for tiny displacements of a thin membrane caused by the mechanical effect of solar chameleons. The displacements are detected by a Michelson interferometer with a homodyne readout scheme. The sensor benefits from the focusing action of the ABRIXAS X-ray telescope installed at CAST, which increases the chameleon flux on the membrane. A mechanical chopper placed between the telescope output and the detector modulates the incoming chameleon stream. We present the results of the solar chameleon measurements taken at CAST in July 2017, setting an upper bound on the force acting on the membrane of $80$ pN at 95\% confidence level. The detector is sensitive for direct coupling to matter $10^4 \leq\beta_m \leq 10^8$, where the coupling to photons is locally bound to $\beta_\gamma \leq 10^{11}$.
Copyright/License	preprint: (License: arXiv nonexclusive-distrib 1.0) publication: © 2019 Published by Elsevier B.V. (License: CC-BY-4.0)

$The exclusion limit for Chameleons at CAST are shown with hatched pattern. The KWISP measurement of this work is illustrated in red colour and comparison to other experimental techniques (\cite{gammev,gammevchase,collider,atomin}) is made, assuming a dark energy scale $\Lambda = 2.4 \cdot 10^{-3}$ eV and $n = 1 $. The limit from the previous CAST measurement \cite{castchin} is based on chameleon-to-photon conversion only. In the parameter space of realistic solar models the expected chameleon production maximum, in darker shade, takes place for $B=30$~T and the tachocline length $L_i = 0.05 R_{Sun}$ while the minimum, in lighter shade, is expected for $B=10$~T and the tachocline length $L_i = 0.01 R_{Sun}$.$ $Calibration graph showing the result of the sine fit. The data points were fitted with the function $I(x) = A \cdot sin(\omega \cdot x+b)+B$\ and the values $A = (133 \pm 4)\cdot 10^2$, $B = -324 \pm 64$, $\omega = 0.02336 \pm 4$, $\varphi = -0.178 \pm 6$ were derived.$