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A state change in the low-mass X-ray binary XSS J12270−4859

Bassa, C. G. and Patruno, A. and Hessels, J. W. T. and Keane, E. F. and Monard, B. and Mahony, E. K. and Bogdanov, S. and Corbel, S. and Edwards, P. G. and Archibald, A. M. and Janssen, G. H. and Stappers, B. W. and Tendulkar, S. (2014) A state change in the low-mass X-ray binary XSS J12270−4859. Monthly Notices of the Royal Astronomical Society, 441 (2). pp. 1825-1830. ISSN 0035-8711.

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Millisecond radio pulsars acquire their rapid rotation rates through mass and angular momentum transfer in a low-mass X-ray binary system. Recent studies of PSR J1824−2452I and PSR J1023+0038 have observationally demonstrated this link, and they have also shown that such systems can repeatedly transition back-and-forth between the radio millisecond pulsar and low-mass X-ray binary states. This also suggests that a fraction of such systems are not newly born radio millisecond pulsars but are rather suspended in a back-and-forth, state-switching phase, perhaps for gigayears. XSS J12270−4859 has been previously suggested to be a low-mass X-ray binary, and until recently the only such system to be seen at MeV–GeV energies. We present radio, optical and X-ray observations that offer compelling evidence that XSS J12270−4859 is a low-mass X-ray binary which transitioned to a radio millisecond pulsar state between 2012 November 14 and December 21. We use optical and X-ray photometry/spectroscopy to show that the system has undergone a sudden dimming and no longer shows evidence for an accretion disc. The optical observations constrain the orbital period to 6.913 ± 0.002 h.

Item Type:Article
Related URLs:
URLURL TypeDescription
Hessels, J. W. T.0000-0003-2317-1446
Keane, E. F.0000-0002-4553-655X
Bogdanov, S.0000-0002-9870-2742
Additional Information:© 2014 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. Accepted 2014 April 8; Received 2014 April 2; In original form 2014 February 4. CGB acknowledges support from ERC Advanced Grant ‘LEAP’ (227947, PI:Michael Kramer). AMA and JWTH acknowledge support from a Vrije Competitie grant from NWO. JWTH and AP acknowledge support from NWO Vidi grants. JWTH also acknowledges funding from an ERC Starting Grant ‘DRAGNET’ (337062). EFK acknowledges the support of the Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO), through project number CE110001020. SC acknowledges the financial support from the UnivEarthS Labex programme of Sorbonne Paris Cité (ANR-10-LABX-0023 and ANR-11-IDEX-0005-02). The Australia Telescope Compact Array and Parkes radio telescope are part of the Australia Telescope National Facility which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO. The work presented was based in part on observations obtained with XMM–Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.
Funding AgencyGrant Number
ERC Advanced Grant 'LEAP'227947
NWO Vrije Competitie grantUNSPECIFIED
ERC Starting Grant 'DRAGNET'337062
Australian Research Council Centre of Excellence for All-sky Astrophysics (CAASTRO)CE110001020
Sorbonne Paris Cité UnivEarthS Labex programmeANR-10-LABX-0023
Sorbonne Paris Cité UnivEarthS Labex programmeANR-11-IDEX-0005-02
Subject Keywords:binaries: general; stars: individual: XSS J12270−4859; stars: neutron; X-rays: binaries
Issue or Number:2
Record Number:CaltechAUTHORS:20140626-084824918
Persistent URL:
Official Citation:Bassa, C. G., Patruno, A., Hessels, J. W. T., Keane, E. F., Monard, B., Mahony, E. K., . . . Tendulkar, S. (2014). A state change in the low-mass X-ray binary XSS J12270−4859. Monthly Notices of the Royal Astronomical Society, 441(2), 1825-1830. doi: 10.1093/mnras/stu708
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46520
Deposited By: Jason Perez
Deposited On:26 Jun 2014 20:45
Last Modified:09 Mar 2020 13:18

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