Details
| Original language | English |
|---|---|
| Pages (from-to) | 915-934 |
| Number of pages | 20 |
| Journal | Monthly Notices of the Royal Astronomical Society |
| Volume | 502 |
| Issue number | 1 |
| Early online date | 23 Nov 2020 |
| Publication status | Published - Mar 2021 |
Abstract
The Fermi Large Area Telescope gamma-ray source 3FGL J2039.6-5618 contains a periodic optical and X-ray source that was predicted to be a 'redback' millisecond pulsar (MSP) binary system. However, the conclusive identification required the detection of pulsations from the putative MSP. To better constrain the orbital parameters for a directed search for gamma-ray pulsations, we obtained new optical light curves in 2017 and 2018, which revealed long-term variability from the companion star. The resulting orbital parameter constraints were used to perform a targeted gamma-ray pulsation search using the Einstein@Home-distributed volunteer computing system. This search discovered pulsations with a period of 2.65 ms, confirming the source as a binary MSP now known as PSR J2039-5617. Optical light-curve modelling is complicated, and likely biased, by asymmetric heating on the companion star and long-term variability, but we find an inclination i ≳ 60°, for a low pulsar mass between 1.1 M⊙ < Mpsr < 1.6 M⊙, and a companion mass of 0.15-0.22 M⊙z, confirming the redback classification. Timing the gamma-ray pulsations also revealed significant variability in the orbital period, which we find to be consistent with quadrupole moment variations in the companion star, suggestive of convective activity. We also find that the pulsed flux is modulated at the orbital period, potentially due to inverse Compton scattering between high-energy leptons in the pulsar wind and the companion star's optical photon field.
Keywords
- binaries: close, gamma-rays: stars, pulsars: individual (PSR J2039-5617), stars: neutron
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Astronomy and Astrophysics
- Earth and Planetary Sciences(all)
- Space and Planetary Science
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In: Monthly Notices of the Royal Astronomical Society, Vol. 502, No. 1, 03.2021, p. 915-934.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Einstein@Home discovery of the gamma-ray millisecond pulsar PSR J2039-5617 confirms its predicted redback nature
AU - Clark, C. J.
AU - Nieder, L.
AU - Voisin, G.
AU - Allen, B.
AU - Aulbert, C.
AU - Behnke, O.
AU - Breton, R. P.
AU - Choquet, C.
AU - Corongiu, A.
AU - Dhillon, V. S.
AU - Eggenstein, H. B.
AU - Fehrmann, H.
AU - Guillemot, L.
AU - Harding, A. K.
AU - Kennedy, M. R.
AU - Machenschalk, B.
AU - Marsh, T. R.
AU - Sánchez, D. Mata
AU - Mignani, R. P.
AU - Stringer, J.
AU - Wadiasingh, Z.
AU - Wu, J.
N1 - Funding Information: CJC, GV, RPB, MRK, DMS, and JS acknowledge support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. 715051; Spiders). VSD and ULTRACAM acknowledge the support of the Science and Technology Facilities Council (STFC). ZW is supported by the National Aeronautics and Space Administration (NASA) postdoctoral program. Einstein@Home is supported by National Science Foundation (NSF) grants 1104902 and 1816904. This paper uses data taken from the XMM-Newton Science Archive (Observation ID: 0720750301) and produced using the Pipeline Processing System. Thiswork hasmade use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/con sortium). Funding for the DPAC has been provided by national institutions, in particular, the institutions participating in the Gaia Multilateral Agreement. This research was made possible through the use of the AAVSO Photometric All-Sky Survey (APASS), funded by the Robert Martin Ayers Sciences Fund and NSF AST-1412587.
PY - 2021/3
Y1 - 2021/3
N2 - The Fermi Large Area Telescope gamma-ray source 3FGL J2039.6-5618 contains a periodic optical and X-ray source that was predicted to be a 'redback' millisecond pulsar (MSP) binary system. However, the conclusive identification required the detection of pulsations from the putative MSP. To better constrain the orbital parameters for a directed search for gamma-ray pulsations, we obtained new optical light curves in 2017 and 2018, which revealed long-term variability from the companion star. The resulting orbital parameter constraints were used to perform a targeted gamma-ray pulsation search using the Einstein@Home-distributed volunteer computing system. This search discovered pulsations with a period of 2.65 ms, confirming the source as a binary MSP now known as PSR J2039-5617. Optical light-curve modelling is complicated, and likely biased, by asymmetric heating on the companion star and long-term variability, but we find an inclination i ≳ 60°, for a low pulsar mass between 1.1 M⊙ < Mpsr < 1.6 M⊙, and a companion mass of 0.15-0.22 M⊙z, confirming the redback classification. Timing the gamma-ray pulsations also revealed significant variability in the orbital period, which we find to be consistent with quadrupole moment variations in the companion star, suggestive of convective activity. We also find that the pulsed flux is modulated at the orbital period, potentially due to inverse Compton scattering between high-energy leptons in the pulsar wind and the companion star's optical photon field.
AB - The Fermi Large Area Telescope gamma-ray source 3FGL J2039.6-5618 contains a periodic optical and X-ray source that was predicted to be a 'redback' millisecond pulsar (MSP) binary system. However, the conclusive identification required the detection of pulsations from the putative MSP. To better constrain the orbital parameters for a directed search for gamma-ray pulsations, we obtained new optical light curves in 2017 and 2018, which revealed long-term variability from the companion star. The resulting orbital parameter constraints were used to perform a targeted gamma-ray pulsation search using the Einstein@Home-distributed volunteer computing system. This search discovered pulsations with a period of 2.65 ms, confirming the source as a binary MSP now known as PSR J2039-5617. Optical light-curve modelling is complicated, and likely biased, by asymmetric heating on the companion star and long-term variability, but we find an inclination i ≳ 60°, for a low pulsar mass between 1.1 M⊙ < Mpsr < 1.6 M⊙, and a companion mass of 0.15-0.22 M⊙z, confirming the redback classification. Timing the gamma-ray pulsations also revealed significant variability in the orbital period, which we find to be consistent with quadrupole moment variations in the companion star, suggestive of convective activity. We also find that the pulsed flux is modulated at the orbital period, potentially due to inverse Compton scattering between high-energy leptons in the pulsar wind and the companion star's optical photon field.
KW - binaries: close
KW - gamma-rays: stars
KW - pulsars: individual (PSR J2039-5617)
KW - stars: neutron
UR - http://www.scopus.com/inward/record.url?scp=85103160357&partnerID=8YFLogxK
U2 - 10.48550/arXiv.2007.14849
DO - 10.48550/arXiv.2007.14849
M3 - Article
AN - SCOPUS:85103160357
VL - 502
SP - 915
EP - 934
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -