Experimental search for the “LSND anomaly” with the ICARUS detector in the CNGS neutrino beam

M. Antonello; B. Baibussinov; P. Benetti; E. Calligarich; N. Canci; S. Centro; A. Cesana; K. Cieślik; D. B. Cline; A. G. Cocco; A. Dabrowska; D. Dequal; A. Dermenev; R. Dolfini; C. Farnese; A. Fava; A. Ferrari; G. Fiorillo; D. Gibin; S. Gninenko; A. Guglielmi; M. Haranczyk; J. Holeczek; A. Ivashkin; M. Kirsanov; J. Kisiel; I. Kochanek; J. Lagoda; S. Mania; A. Menegolli; G. Meng; C. Montanari; S. Otwinowski; A. Piazzoli; P. Picchi; F. Pietropaolo; P. Plonski; A. Rappoldi; G. L. Raselli; M. Rossella; C. Rubbia; P. R. Sala; E. Scantamburlo; A. Scaramelli; E. Segreto; F. Sergiampietri; D. Stefan; J. Stepaniak; R. Sulej; M. Szarska; M. Terrani; F. Varanini; S. Ventura; C. Vignoli; H. G. Wang; X. Yang; A. Zalewska; K. Zaremba

doi:10.1140/epjc/s10052-013-2345-6

2024 Impact factor 4.8

Particles and Fields

Open Access

Eur. Phys. J. C (2013) 73: 2345
https://doi.org/10.1140/epjc/s10052-013-2345-6

Regular Article - Experimental Physics

Experimental search for the “LSND anomaly” with the ICARUS detector in the CNGS neutrino beam

M. Antonello¹, B. Baibussinov², P. Benetti³, E. Calligarich³, N. Canci¹, S. Centro², A. Cesana⁴, K. Cieślik⁵, D. B. Cline⁶, A. G. Cocco⁷, A. Dabrowska⁵, D. Dequal², A. Dermenev⁸, R. Dolfini³, C. Farnese², A. Fava², A. Ferrari⁹, G. Fiorillo⁷, D. Gibin², S. Gninenko⁸, A. Guglielmi², M. Haranczyk⁵, J. Holeczek¹⁰, A. Ivashkin¹⁰, M. Kirsanov⁸, J. Kisiel¹⁰, I. Kochanek¹⁰, J. Lagoda¹¹, S. Mania¹⁰, A. Menegolli³, G. Meng², C. Montanari³, S. Otwinowski⁶, A. Piazzoli³, P. Picchi¹², F. Pietropaolo², P. Plonski¹³, A. Rappoldi³, G. L. Raselli³, M. Rossella³, C. Rubbia¹^,9, P. R. Sala¹⁵^*, E. Scantamburlo¹, A. Scaramelli¹⁵, E. Segreto¹, F. Sergiampietri¹⁴, D. Stefan¹, J. Stepaniak¹¹, R. Sulej¹^,11, M. Szarska⁵, M. Terrani⁴, F. Varanini², S. Ventura², C. Vignoli¹, H. G. Wang⁶, X. Yang⁶, A. Zalewska⁵ and K. Zaremba¹³

¹ INFN—Laboratori Nazionali del Gran Sasso, Assergi, Italy
² Università di Padova e INFN, Padova, Italy
³ Università di Pavia e INFN, Pavia, Italy
⁴ Politecnico di Milano e INFN, Milano, Italy
⁵ H. Niewodniczański Institute of Nuclear Physics, Kraków, Poland
⁶ Department of Physics, UCLA, Los Angeles, USA
⁷ Università Federico II di Napoli e INFN, Napoli, Italy
⁸ Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, Russia
⁹ CERN, Geneva, Switzerland
¹⁰ A. Sołtan Institute for Nuclear Studies, Warszawa, Poland
¹¹ Institute of Physics, University of Silesia, Katowice, Poland
¹² INFN Laboratori Nazionali di Frascati, Frascati, Italy
¹³ Institute for Radioelectronics, Warsaw University of Technology, Warsaw, Poland
¹⁴ Università di Pisa e INFN, Pisa, Italy
¹⁵ INFN Milano, Milano, Italy

^* e-mail: paola.sala@mi.infn.it

Received: 28 January 2013
Revised: 13 February 2013
Published online: 13 March 2013

Abstract

We report an early result from the ICARUS experiment on the search for a ν _μ→ν _e signal due to the LSND anomaly. The search was performed with the ICARUS T600 detector located at the Gran Sasso Laboratory, receiving CNGS neutrinos from CERN at an average energy of about 20 GeV, after a flight path of ∼730 km. The LSND anomaly would manifest as an excess of ν _e events, characterized by a fast energy oscillation averaging approximately to $\sin^{2}(1.27\Delta m^{2}_{\mathrm{new}}L/E_{\nu})\approx 1/2$ with probability $P_{\nu_{\mu}\rightarrow \nu_{e}} = 1/2 \sin^{2}(2\theta_{\mathrm{new}})$ . The present analysis is based on 1091 neutrino events, which are about 50 % of the ICARUS data collected in 2010–2011. Two clear ν _e events have been found, compared with the expectation of 3.7±0.6 events from conventional sources. Within the range of our observations, this result is compatible with the absence of a LSND anomaly. At 90 % and 99 % confidence levels the limits of 3.4 and 7.3 events corresponding to oscillation probabilities $\langle P_{\nu_{\mu}\rightarrow \nu_{e}}\rangle \le 5.4 \times 10^{-3}$ and $\langle P_{\nu_{\mu}\rightarrow \nu_{e}}\rangle \le 1.1 \times 10^{-2}$ are set respectively. The result strongly limits the window of open options for the LSND anomaly to a narrow region around (Δm ²,sin²(2θ))_new=(0.5 eV²,0.005), where there is an overall agreement (90 % CL) between the present ICARUS limit, the published limits of KARMEN and the published positive signals of LSND and MiniBooNE Collaborations.