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arXiv · 2001.02722

Searching for optical companions to four binary millisecond pulsars with the Gran Telescopio Canarias

A. Yu. Kirichenko·A. V. Karpova·D. A. Zyuzin·S. V. Zharikov·E. A. Lopez·Yu. A. Shibanov·P. C. C. Freire·E. Fonseca·A. Cabrera-Lavers
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Abstract

We report on multi-band photometric observations of four binary millisecond pulsars with the Gran Telescopio Canarias. The observations led to detection of binary companions to PSRs J1630+3734, J1741+1351 and J2042+0246 in the Sloan g', r' and i' bands. Their magnitudes in the r' band are $\approx$24.4, 24.4 and 24.0, respectively. We also set a 3$σ$ upper limit on the brightness of the PSR J0557+1550 companion in the r' band of $\approx$25.6 mag. Combining the optical data with the radio timing measurements and white dwarf cooling models, we show that the detected companions are cool low-mass white dwarfs with temperatures and ages in the respective ranges of (4-7)$\times 10^3$ K and 2-5 Gyr. All the detected white dwarfs are found to likely have either pure hydrogen or mixed helium-hydrogen atmospheres.

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A. Yu. Kirichenko, A. V. Karpova, D. A. Zyuzin, S. V. Zharikov, E. A. Lopez, Yu. A. Shibanov, P. C. C. Freire, E. Fonseca, A. Cabrera-Lavers. 2020-01-08. Searching for optical companions to four binary millisecond pulsars with the Gran Telescopio Canarias. https://doi.org/10.1093/mnras%2Fstaa066

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