The Identification of the White Dwarf Companion to the Millisecond Pulsar J2317+1439

Abstract

We report identification of the optical counterpart to the companion of the millisecond pulsar J2317+1439. At the timing position of the pulsar, we find an object with g = 22.96 ± 0.05, r = 22.86 ± 0.04 and i = 22.82 ± 0.05. The magnitudes and colors of the object are consistent with it being a white dwarf. By comparing with white dwarf cooling models, we estimate that it has a mass of 0.39 +0.13 −0.10 M , an effective temperature of 8077 +550 −470 K and a cooling age of 10.9 ± 0.3 Gyr. Combining our results with published constraints on the orbital parameters obtained through pulsar timing, we estimate the pulsar mass to be 3.4 +1.4 −1.1 M . Although the constraint on the pulsar mass is still weak, there is a significant possibility that the pulsar could be more massive than two solar mass.

The ultracool helium-atmosphere white dwarf companion of PSR J0740+6620?

“…This value was transformed to the extinction correction values A r ′ = 0.09 ± 0.05 and A i ′ = 0.07 ± 0.03 using the conversion coefficients presented by Schlafly & Finkbeiner (2011). (Nicastro et al 1995), J1231−1411 (Bassa et al 2016) and J2317+1439 (Dai et al 2017). We also include two ultracool isolated WDs: SDSS J110217.48+411315.4 (hereafter WD J1102; Hall et al 2008;Kilic et al 2012) and WD 0346+246 (Oppenheimer et al 2001).…”

“…Nevertheless, increasing the number of such identifications is important for understanding the nature and origin of these systems. The situation has been improving thanks to the world's largest telescopes and deep sky surveys (e.g., Bassa et al 2016;Dai et al 2017;Karpova et al 2018;Kirichenko et al 2018). The subject of this paper, the binary MSP J0740+6620 (hereafter J0740), was discovered in the radio in the frame of the Green Bank North Celestial Cap Pulsar Survey (Stovall et al 2014;Lynch et al 2018).…”

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

“…To better constrain the WD parameters for this system, we utilised the procedure described by Dai et al (2017) and used the models for helium-core hydrogen-atmosphere WDs with masses of 0.1554-0.4352 M ⊙ and the CO-core hydrogen-atmosphere WDs with masses of 0.5-1.0 M ⊙ . The models were interpolated in the mass-temperature plane within a mass range of 0.1554-1.0 M ⊙ and a temperature range of 3000-10000 K using a 7000×7000 grid.…”

“…The models were interpolated in the mass-temperature plane within a mass range of 0.1554-1.0 M ⊙ and a temperature range of 3000-10000 K using a 7000×7000 grid. Then the likelihood of each model point was calculated according to formula (5) from Dai et al (2017). We assumed the distance range between D YMW16 and D NE2001 , i.e.…”

“…a In the case of the NE2001 model (Cordes & Lazio 2002), the distances D NE2001 are 2.92 (J0557+1550), 0.94 (J1630+3734), 0.9 (J1741+1351) and 0.83 (J2042+0246) kpc. b A minimum companion mass is calculated assuming the inclination angle of the binary orbit i = 90 • and the pulsar mass M p = have triggered intensive studies with large optical telescopes (Bassa et al 2016;Dai et al 2017;Kirichenko et al 2018;Beronya et al 2019).…”