Gamma-ray observations of the Be/pulsar binary 1A 0535+262 during a giant X-ray outburst

Abstract

Giant X-ray outbursts, with luminosities of about $10^{37}$ erg s${}^{-1}$, are observed roughly every 5 years from the nearby Be/pulsar binary 1A 0535+262. In this article, we present observations of the source with VERITAS at very-high energies (VHE; E$>$100 GeV) triggered by the X-ray outburst in December 2009. The observations started shortly after the onset of the outburst, and they provided comprehensive coverage of the episode, as well as the 111-day binary orbit. No VHE emission is evident at any time. We also examined data from the contemporaneous observations of 1A 0535+262 with the Fermi/LAT at high energy photons (HE; E$>$0.1 GeV) and failed to detect the source at GeV energies. The X-ray continua measured with the Swift/XRT and the RXTE/PCA can be well described by the combination of blackbody and Comptonized emission from thermal electrons. Therefore, the gamma-ray and X-ray observations suggest the absence of a significant population of non-thermal particles in the system. This distinguishes 1A~0535+262 from those Be X-ray binaries (such as PSR B1259--63 and LS I +61${}^{\circ }$303) that have been detected at GeV--TeV energies. We discuss the implications of the results on theoretical models.

28 pages, 4 figures; accepted by The Astrophysical Journal updated references

References in corpus (15)

• Fermi Large Area Telescope First Source Catalog
• Catalogue of high-mass X-ray binaries in the Galaxy ($4^{th}$ edition)
• The Constant Inner-Disk Radius of LMC X-3: A Basis for Measuring Black Hole Spin
• Observation of Supernova Remnant IC443 with the Fermi Large Area Telescope
• VERITAS Observations of the gamma-Ray Binary LS I +61 303
• Discovery of a point-like very-high-energy gamma-ray source in Monoceros
• HESS J0632+057 : A new gamma-ray binary?
• A 0535+26 in the August/September 2005 outburst observed by RXTE and INTEGRAL
• Gamma-Hadron Separation Methods for the VERITAS Array of Four Imaging Atmospheric Cherenkov Telescopes
• Fermi LAT observations of the Geminga pulsar
• A 0535+26: Back in business
• On the neutron star-disc interaction in Be/X-ray binaries
• Broad band X-ray spectroscopy of A0535+262 with SUZAKU
• Inverse Compton e-p pair cascade model for the gamma-ray production in massive binary LSI +61^o 303
• Very high energy gamma-ray emission from X-ray transients during major outbursts

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• A propeller scenario for the gamma-ray emission of low-mass X-ray binaries: The case of XSS J12270-4859
• X-Ray and Optical Observations of A 0535+26
• A0535+26 in the April 2010 outburst: probing the accretion regime at work
• The frequency of Kozai-Lidov disc oscillation driven giant outbursts in Be/X-ray binaries
• INTEGRAL and Swift observations of the Be X-ray binary 4U 1036-56 (RX J1037.5-5647) and its possible relation with gamma-ray transients
• The Galactic high mass X-ray binary population with Fermi -LAT
• Chandra Imaging of Gamma-Ray Binaries
• X-ray spectral-timing variability of 1A 0535+262 during the 2020 giant outburst
• Deep search for gamma-ray emission from the accreting X-ray pulsar 1A 0535+262
• Very-high-energy observations of the binaries V 404 Cyg and 4U 0115+634 during giant X-ray outbursts
• The likely Fermi detection of the Be X-ray binary GRO J1008-57: hint for gamma-ray production in neutron-star X-ray binaries
• State-Dependent Orbital Modulation of X-rays in CYG X-3
• TeV and optical observations of the Be/pulsar binary 1A0535+262 during the 2020 giant outburst