First direct observation of muon antineutrino disappearance

P Adamson; C Andreopoulos; D J Auty; D S Ayres; C Backhouse; G Barr; M Bishai; A Blake; G J Bock; D J Boehnlein; D Bogert; S Cavanaugh; D Cherdack; S Childress; B C Choudhary; J A B Coelho; S J Coleman; L Corwin; D Cronin-Hennessy; I Z Danko; J K de Jong; N E Devenish; M V Diwan; M Dorman; C O Escobar; J J Evans; E Falk; G J Feldman; M V Frohne; H R Gallagher; R A Gomes; M C Goodman; P Gouffon; N Graf; R Gran; N Grant; K Grzelak; A Habig; D Harris; J Hartnell; R Hatcher; A Himmel; A Holin; C Howcroft; X Huang; J Hylen; J Ilic; G M Irwin; Z Isvan; D E Jaffe; C James; D Jensen; T Kafka; S M S Kasahara; G Koizumi; S Kopp; M Kordosky; A Kreymer; K Lang; G Lefeuvre; J Ling; P J Litchfield; L Loiacono; P Lucas; W A Mann; M L Marshak; N Mayer; A M McGowan; R Mehdiyev; J R Meier; M D Messier; W H Miller; S R Mishra; J Mitchell; C D Moore; J Morfín; L Mualem; S Mufson; J Musser; D Naples; J K Nelson; H B Newman; R J Nichol; T C Nicholls; J A Nowak; J P Ochoa-Ricoux; W P Oliver; M Orchanian; R Ospanov; J Paley; R B Patterson; G Pawloski; G F Pearce; D A Petyt; S Phan-Budd; R K Plunkett; X Qiu; J Ratchford; T M Raufer; B Rebel; P A Rodrigues; C Rosenfeld; H A Rubin; M C Sanchez; J Schneps; P Schreiner; P Shanahan; A Sousa; P Stamoulis; M Strait; N Tagg; R L Talaga; E Tetteh-Lartey; J Thomas; M A Thomson; G Tinti; R Toner; G Tzanakos; J Urheim; P Vahle; B Viren; A Weber; R C Webb; C White; L Whitehead; S G Wojcicki; T Yang; R Zwaska; MINOS Collaboration

doi:10.1103/PhysRevLett.107.021801

First direct observation of muon antineutrino disappearance

Phys Rev Lett. 2011 Jul 8;107(2):021801. doi: 10.1103/PhysRevLett.107.021801. Epub 2011 Jul 5.

Authors

P Adamson¹, C Andreopoulos, D J Auty, D S Ayres, C Backhouse, G Barr, M Bishai, A Blake, G J Bock, D J Boehnlein, D Bogert, S Cavanaugh, D Cherdack, S Childress, B C Choudhary, J A B Coelho, S J Coleman, L Corwin, D Cronin-Hennessy, I Z Danko, J K de Jong, N E Devenish, M V Diwan, M Dorman, C O Escobar, J J Evans, E Falk, G J Feldman, M V Frohne, H R Gallagher, R A Gomes, M C Goodman, P Gouffon, N Graf, R Gran, N Grant, K Grzelak, A Habig, D Harris, J Hartnell, R Hatcher, A Himmel, A Holin, C Howcroft, X Huang, J Hylen, J Ilic, G M Irwin, Z Isvan, D E Jaffe, C James, D Jensen, T Kafka, S M S Kasahara, G Koizumi, S Kopp, M Kordosky, A Kreymer, K Lang, G Lefeuvre, J Ling, P J Litchfield, L Loiacono, P Lucas, W A Mann, M L Marshak, N Mayer, A M McGowan, R Mehdiyev, J R Meier, M D Messier, W H Miller, S R Mishra, J Mitchell, C D Moore, J Morfín, L Mualem, S Mufson, J Musser, D Naples, J K Nelson, H B Newman, R J Nichol, T C Nicholls, J A Nowak, J P Ochoa-Ricoux, W P Oliver, M Orchanian, R Ospanov, J Paley, R B Patterson, G Pawloski, G F Pearce, D A Petyt, S Phan-Budd, R K Plunkett, X Qiu, J Ratchford, T M Raufer, B Rebel, P A Rodrigues, C Rosenfeld, H A Rubin, M C Sanchez, J Schneps, P Schreiner, P Shanahan, A Sousa, P Stamoulis, M Strait, N Tagg, R L Talaga, E Tetteh-Lartey, J Thomas, M A Thomson, G Tinti, R Toner, G Tzanakos, J Urheim, P Vahle, B Viren, A Weber, R C Webb, C White, L Whitehead, S G Wojcicki, T Yang, R Zwaska; MINOS Collaboration

Affiliation

¹ Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.

PMID: 21797594
DOI: 10.1103/PhysRevLett.107.021801

Abstract

This Letter reports the first direct observation of muon antineutrino disappearance. The MINOS experiment has taken data with an accelerator beam optimized for ν(μ) production, accumulating an exposure of 1.71 × 10²⁰ protons on target. In the Far Detector, 97 charged current ν(μ) events are observed. The no-oscillation hypothesis predicts 156 events and is excluded at 6.3σ. The best fit to oscillation yields |Δm²| = [3.36(-0.40)(+0.46)(stat) ± 0.06(syst)] × 10⁻³ eV², sin²(2θ) = 0.86(-0.12)(+0.11)(stat) ± 0.01(syst). The MINOS ν(μ) and ν(μ) measurements are consistent at the 2.0% confidence level, assuming identical underlying oscillation parameters.