标题： PSR J0210+5845；一颗与B6V主序星伴星构成的超宽轨道毫秒脉冲星 显示英文标题

标题： PSR J0210+5845; An ultra wide binary pulsar with a B6V main-sequence star companion

摘要： 我们报道了对PSR J0210+5845的射电脉冲计时观测，结果显示其自转减速行为存在较大的偏差。我们认为这些偏差是由双星运动引起的，该双星系统围绕着一颗$V=13.5$星2MASS J02105640$+$5845176运行，这颗恒星在天球位置和距离上与脉冲星相一致。存档观测和新的光学光谱数据表明，这颗恒星是一颗温度为$T_\mathrm{eff}\approx 14\,000$K、质量为$M_\mathrm{c}= 3.5$至$3.8$M$_\odot$的B6V型恒星，使其成为已知环绕非回收脉冲星的最低质量主序星。 我们发现，观测到的轨道时间约束该双星轨道为宽且适度偏心，轨道周期为$P_\mathrm{b}=47^{+40}_{-14}$年，偏心率为$e=0.46^{+0.10}_{-0.07}$。 我们预测，下次近日点经过将发生在 2030 年至 2034 年之间。 由于伴星质量较低，我们得出结论，具有 PSR J0210+5845 及其双星伴星属性的系统在超新星爆发中存活下来的概率很低。 我们表明，在超新星爆炸期间，双星系统需要一个低速且偶然方向的初生反冲速度才能保持结合状态，并论证电子俘获型超新星可能是该脉冲星的形成场景。 显示英文摘要

摘要： We report on radio timing observations of PSR J0210+5845 which reveal large deviations from typical pulsar spin-down behaviour. We interpret these deviations as being due to binary motion around the $V=13.5$ star 2MASS J02105640$+$5845176, which is coincident in celestial position and distance with the pulsar. Archival observations and new optical spectroscopy identify this star as a B6V star with a temperature of $T_\mathrm{eff}\approx 14\,000$K and a mass of $M_\mathrm{c}= 3.5$ to $3.8$M$_\odot$, making it the lowest mass main-sequence star known orbiting a non-recycled pulsar. We found that the timing observations constrain the binary orbit to be wide and moderately eccentric, with an orbital period of $P_\mathrm{b}=47^{+40}_{-14}$yr and eccentricity $e=0.46^{+0.10}_{-0.07}$. We predict that the next periastron passage will occur between 2030 and 2034. Due to the low companion mass, we find that the probability for a system with the properties of PSR J0210+5845 and its binary companion to survive the supernova is low. We show that a low velocity and fortuitously directed natal kick is required for the binary to remain bound during the supernova explosion, and argue that an electron-capture supernova is a plausible formation scenario for the pulsar.