TY - JOUR
T1 - The 11 yr of low activity of the magnetar XTE J1810−197
AU - Pintore, Fabio
AU - Mereghetti, Sandro
AU - Esposito, Paolo
AU - Turolla, Roberto
AU - Tiengo, Andrea
AU - Rea, Nanda
AU - Bernardini, Federico
AU - Israel, Gian Luca
N1 - Funding Information:
We used observations obtained with XMM–Newton an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, the NASA Chandra, and NICER missions. We acknowledge financial contribution from the agreement ASI-INAF I/037/12/0. We acknowledges support from the HERMES Project, financed by the Italian Space Agency (ASI) Agreement n. 2016/13 U.O. FB is f−unded by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement n. 664931. PE acknowledges funding in the framework of the project ULTraS, ASI–INAF contract N. 2017-14-H.0. We also thank the referee for his useful suggestions.
Funding Information:
We used observations obtained with XMM–Newton an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA, the NASA Chandra, and NICER missions. We acknowledge financial contribution from the agreement ASI-INAF I/037/12/0. We acknowledges support from the HERMES Project, financed by the Italian Space Agency (ASI) Agreement n. 2016/13 U.O. FB is f−unded by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement n. 664931. PE acknowledges funding in the framework of the project ULTraS, ASI–INAF contract N. 2017-14-H.0.
Publisher Copyright:
© 2018 The Author(s).
PY - 2019/3/1
Y1 - 2019/3/1
N2 - In 2003, the magnetar XTE J1810−197 started an outburst that lasted until early 2007. In the following 11 yr, the source stayed in a quiescent/low-activity phase. XTE J1810−197 is one of the closest magnetars, hence its X-ray properties can be studied in detail even in quiescence and an extended monitoring has been carried out to study its long-term timing and spectral evolution. Here, we report the results of new X-ray observations, taken between 2017 September and 2018 April, with XMM–Newton, Chandra, and NICER. We derived a phase-connected timing solution yielding a frequency derivative of −9.26(6) × 10−14 Hz s−1. This value is consistent with that measured between 2009 and 2011, indicating that the pulsar spin-down rate remained quite stable during the long quiescent period. A spectral analysis of all the X-ray observations taken between 2009 and 2018 does not reveal significant spectral and/or flux variability. The spectrum of XTE J1810−197 can be described by the sum of two thermal components with temperatures of 0.15 and 0.3 keV, plus a power-law component with photon index 0.6. We also found evidence for an absorption line at ∼1.2 keV and width of 0.1 keV. Due to the long exposure time of the summed XMM–Newton observations, we could also carry out a phase-resolved spectral analysis for this source in quiescence. This showed that the flux modulation can be mainly ascribed to the warmer of the two thermal components, whose flux varies by ∼45 per cent along the pulse phase.
AB - In 2003, the magnetar XTE J1810−197 started an outburst that lasted until early 2007. In the following 11 yr, the source stayed in a quiescent/low-activity phase. XTE J1810−197 is one of the closest magnetars, hence its X-ray properties can be studied in detail even in quiescence and an extended monitoring has been carried out to study its long-term timing and spectral evolution. Here, we report the results of new X-ray observations, taken between 2017 September and 2018 April, with XMM–Newton, Chandra, and NICER. We derived a phase-connected timing solution yielding a frequency derivative of −9.26(6) × 10−14 Hz s−1. This value is consistent with that measured between 2009 and 2011, indicating that the pulsar spin-down rate remained quite stable during the long quiescent period. A spectral analysis of all the X-ray observations taken between 2009 and 2018 does not reveal significant spectral and/or flux variability. The spectrum of XTE J1810−197 can be described by the sum of two thermal components with temperatures of 0.15 and 0.3 keV, plus a power-law component with photon index 0.6. We also found evidence for an absorption line at ∼1.2 keV and width of 0.1 keV. Due to the long exposure time of the summed XMM–Newton observations, we could also carry out a phase-resolved spectral analysis for this source in quiescence. This showed that the flux modulation can be mainly ascribed to the warmer of the two thermal components, whose flux varies by ∼45 per cent along the pulse phase.
KW - Magnetic fields
KW - Pulsars: individual: XTE J1810-197
KW - Stars: magnetars
KW - Stars: neutron
KW - X-rays: stars
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U2 - 10.1093/mnras/sty3378
DO - 10.1093/mnras/sty3378
M3 - Article
AN - SCOPUS:85064454928
SN - 0035-8711
VL - 483
SP - 3832
EP - 3838
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -