RT Journal Article
T1 Observation of the black widow B1957+20 millisecond pulsar binary system with the MAGIC telescopes
A1 Barrio Uña, Juan Abel
A1 Bonnefoy, Simon
A1 Contreras González, José Luis
A1 Domínguez Díaz, Alberto
A1 Fidalgo, David Friedrich Carreto
A1 Fonseca González, Mª Victoria
A1 López Moya, Marcos
A1 Nievas Rosillo, Mireia
A1 Ahnen, L.M.
A1 Ansoldi, S.
A1 Otros, ...
AB Spontaneous breaking of Lorentz symmetry at energies on the order of the Planck energy or lower is predicted by many quantum gravity theories, implying non-trivial dispersion relations for the photon in vacuum. Consequently, gamma-rays of different energies, emitted simultaneously from astrophysical sources, could accumulate measurable differences in their time of flight until they reach the Earth. Such tests have been carried out in the past using fast variations of gamma-ray flux from pulsars, and more recently from active galactic nuclei and gamma-ray bursts. We present new constraints studying the gamma-ray emission of the galactic Crab Pulsar, recently observed up to TeV energies by the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) collaboration. A profile likelihood analysis of pulsar events reconstructed for energies above 400. GeV finds no significant variation in arrival time as their energy increases.. Ninety-five percent CL limits are obtained on the effective Lorentz invariance violating energy scale at the level of E-QG1 > 5.5 x 10(17) GeV (4.5 x 10(17) GeV) for a linear, and E-QG2 > 5.9 x 10(10) GeV (5.3 x 10(10) GeV) for a quadratic scenario, for the subluminal and the superluminal cases, respectively. A substantial part of this study is dedicated to calibration of the test statistic, with respect to bias and coverage properties. Moreover, the limits take into account systematic uncertainties, which are found to worsen the statistical limits by about 36%-42%. Our constraints would have been much more stringent if the intrinsic pulse shape of the pulsar between 200 GeV and 400 GeV was understood in sufficient detail and allowed inclusion of events well below 400 GeV.
PB Oxford University Press.
SN 0035-8711
YR 2017
FD 2017-10
LK https://hdl.handle.net/20.500.14352/18349
UL https://hdl.handle.net/20.500.14352/18349
LA eng
NO ©2017 Oxford University Press.Artículo firmado por más de diez autores.We would like to thank the Instituto de Astrofiisica de Canarias for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The financial support of the German BMBF and MPG, the Italian INFN and INAF, the Swiss National Fund SNF, the ERDF under the Spanish MINECO (FPA2015-69818-P, FPA2012-36668, FPA2015-68378-P, FPA2015-69210C6-2-R, FPA2015-69210-C6-4-R, FPA2015-69210-C6-6-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2015-71662-C2-2-P, CSD2009-00064) and the Japanese JSPS and MEXT is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia 'Severo Ochoa' SEV-2012-0234 and SEV-2015-0548, and Unidad de Excelencia 'Maria de Maeztu' MDM-2014-0369, by the Croatian Science Foundation (HrZZ) Project 09/176 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, and by the Polish Narodowe Centrum Nauki grant 2016/22/M/ST9/00382. This work is partially supported by the grant through the Polish Narodowe Centrum Nauki No. 2014/15/B/ST9/04043. The Nancay Radio Observatory is operated by the Paris Observatory, associated with the French Centre National de la Recherche Scientifique (CNRS).
NO Ministerio de Economía y Competitividad (MINECO)
NO German BMBF
NO German MPG
NO Italian INFN
NO Italian INAF
NO Swiss National Fund SNF
NO ERDF
NO Centro de Excelencia Severo Ochoa
NO Unidad de Excelencia María de Maeztu
NO Croatian Science Foundation (HrZZ)
NO University of Rijeka
NO DFG Collaborative Research Centers
NO Polish Narodowe Centrum Nauki
DS Docta Complutense
RD 8 may 2024