arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1708.07041astro-ph.HEastro-ph.SR
收藏

过渡毫秒脉冲星XSS J12270-4859和PSR J1023 +0038射电脉冲星态的中紫外研究

Mid-UV Studies of the Transitional Millisecond Pulsars XSS J12270-4859 and PSR J1023+0038 During Their Radio Pulsar States

L. E. Rivera Sandoval, J. V. Hernandez Santisteban, N. Degenaar, R. Wijnands, C. Knigge, J. M. Miller, M. Reynolds, D. Altamirano, M. van den Berg, A. Hill

摘要:

本文报道了用HST/WFC 3、Swift/UVOT和GALEX/NUV对过渡毫秒双星XSS J12270-4859和PSR J1023+0038在射电脉冲星状态下的中紫外(MUV)观测结果。这两个系统都在我们的图像中被检测到,并显示出MUV的可变性。在相似的轨道相位下,两颗双星的MUV光度相当。这表明两个物体的发射过程是相似的。我们估计的质量比,同伴的温度,倾角和距离XSS J12270-4859的限制,通过使用马尔可夫链蒙特卡罗算法,以适应出版的折叠光学光变曲线。使用所得到的参数,我们在我们的HST过滤器中建模MUV光曲线。由此产生的模型不符合我们的MUV观测。将XSS J12270-4859的质量比固定为其他研究中报告的值,我们获得了约3.2 kpc的距离。这比从无线电测量中得出的结果(约1.4千秒差距)要大。假设质量比的先验是均匀的,则距离与无线电测量的距离相似。然而,它需要一个质量较小的伴星(~0.01 M_sun)。我们的结论是,一个直接加热模型不能完全解释在光学和MUV的观察。因此,需要额外的辐射源。该源可能是一个双星内的冲击,有助于MUV流量,并可能为光学之一。在射电脉冲星状态下,用GALEX探测到PSR J1023+0038的MUV轨道变化,表明存在非对称双星内激波。

英文摘要:

We report mid-UV (MUV) observations taken with HST/WFC3, Swift/UVOT and GALEX/NUV of the transitional millisecond pulsars XSS J12270-4859 and PSR J1023+0038 during their radio pulsar states. Both systems were detected in our images and showed MUV variability. At similar orbital phases, the MUV luminosities of both pulsars are comparable. This suggests that the emission processes involved in both objects are similar. We estimated limits on the mass ratio, companion's temperature, inclination, and distance to XSS J12270-4859 by using a Markov Chain Monte Carlo algorithm to fit published folded optical light curves. Using the resulting parameters, we modeled MUV light curves in our HST filters. The resulting models failed to fit our MUV observations. Fixing the mass ratio of XSS J12270-4859 to the value reported in other studies, we obtained a distance of ~3.2 kpc. This is larger than the one derived from radio measurements (~1.4 kpc). Assuming a uniform prior for the mass ratio, the distance is similar to that from radio measurements. However, it requires an undermassive companion (~0.01 M_sun). We conclude that a direct heating model alone can not fully explain the observations in optical and MUV. Therefore, an additional radiation source is needed. The source could be an intrabinary shock which contributes to the MUV flux and likely to the optical one as well. During the radio pulsar state, the MUV orbital variations of PSR J1023+0038 detected with GALEX, suggests the presence of an asymmetric intrabinary shock.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑