论文标题
PSR J1012+5307的非常长的基线天文学及其对替代性重力理论的影响
Very long baseline astrometry of PSR J1012+5307 and its implications on alternative theories of gravity
论文作者
论文摘要
PSR J1012+5307是轨道上的毫秒脉冲星，带有氦白矮人（WD），已经定时使用了25年的时间。这个长期时机的主要目标之一是在中子恒星和WD之间使用大型不对称性来检验引力理论。但是，此类测试最终将受到与Pulsar距离的准确性的限制。在这里，我们介绍VLBI（非常长的基线干涉法）在PSR J1012+5307大约2。5年的vlbi（作为MSPSRPI项目的一部分）中，其结果为2。5年。这些提供了在准惯性参考框架中测量的PSR J1012+5307的第一个正确运动和绝对位置。从VLBI的结果中，我们的距离为$ 0.83^{+0.06} _ { - 0.02} $ kpc（摘要中提出的所有估计值均为68％的信心），对于迄今为止获得的最精确。使用新的距离，我们改善了未建模对轨道时期衰减的贡献的不确定性，该贡献与其他三个脉冲发生在一起，对偶极重力辐射的耦合常数$κ_d=（-1.7 \ pm1.7 \ pm1.7）\ times 10^{ - 4} $ deveritiation new new new new new new new new new newwortival of偶极辐射$κ_d=（-1.7 \ pm1.7） $ \ dot {g}/g = -1.8^{\，+5.6} _ {\， - 4.7} \ times 10^{ - 13} \，{\ rm yr^{ - 1}} $在本地宇宙中。由于四个领先的PULSAR-WD系统的观察到轨道时期的不确定性在$ \ \ \ 10 $年内可忽略不计，因此对于$ \ dot {g}/g $和$κ_D$的不确定性将被提高至$ \ $ \ $ \ $ \ leq leq1.5 \ leq1.5 \ times10^{ - 13}^{ - 13} $ and y。 $ \ leq1.0 \ times10^{ - 4} $，主要受距离不确定性的限制。
PSR J1012+5307, a millisecond pulsar in orbit with a helium white dwarf (WD), has been timed with high precision for about 25 years. One of the main objectives of this long-term timing is to use the large asymmetry in gravitational binding energy between the neutron star and the WD to test gravitational theories. Such tests, however, will be eventually limited by the accuracy of the distance to the pulsar. Here, we present VLBI (very long baseline interferometry) astrometry results spanning approximately 2.5 years for PSR J1012+5307, obtained with the Very Long Baseline Array as part of the MSPSRPI project. These provide the first proper motion and absolute position for PSR J1012+5307 measured in a quasi-inertial reference frame. From the VLBI results, we measure a distance of $0.83^{+0.06}_{-0.02}$kpc (all the estimates presented in the abstract are at 68% confidence) for PSR J1012+5307, which is the most precise obtained to date. Using the new distance, we improve the uncertainty of measurements of the unmodeled contributions to orbital period decay, which, combined with three other pulsars, places new constraints on the coupling constant for dipole gravitational radiation $κ_D=(-1.7\pm1.7)\times 10^{-4}$ and the fractional time derivative of Newton's gravitational constant $\dot{G}/G = -1.8^{\,+5.6}_{\,-4.7}\times 10^{-13}\,{\rm yr^{-1}}$ in the local universe. As the uncertainties of the observed decays of orbital period for the four leading pulsar-WD systems become negligible in $\approx10$ years, the uncertainties for $\dot{G}/G$ and $κ_D$ will be improved to $\leq1.5\times10^{-13}\,{\rm yr^{-1}}$ and $\leq1.0\times10^{-4}$, respectively, predominantly limited by the distance uncertainties.
