Parkes observations for project P427 semester 2007APRS

Timing the dozen pulsars discovered in P303 is ensuring high quality results: (a) the peculiarities (in position or projected acceleration) of all the 5 millisecond pulsars in NGC6752 suggested the presence of non thermal dynamics in the core, perhaps due to black-holes of intermediate mass; (b) the eclipsing pulsar in NGC6397 appears the best laboratory for studying formation and evolution of exotic binaries. We propose to continue our timing project focusing mostly on NGC6752 at 20cm (in order to measure additional parameters useful to constrain the existence of a black-hole) and NGC6397 at 10cm (for studying the eclipse region and orbital secular evolution). We also request observations in order to confirm candidates resulting from reprocessing of the data with a code sensitive to pulsars in close binaries.

对P303中发现的12颗脉冲星（pulsar）进行计时观测，旨在确保高质量的结果：(a) NGC6752中5颗毫秒脉冲星（millisecond pulsar）的特性（位置或投影加速度方面）表明其核心存在非热动力学过程，这可能源于中等质量黑洞（intermediate-mass black hole）；(b) NGC6397中的食脉冲星（eclipsing pulsar）是研究奇异双星形成与演化的最佳实验室。我们提议继续开展计时观测项目，重点关注NGC6752的20厘米波长观测（以测量更多有助于约束黑洞存在的参数）以及NGC6397的10厘米波长观测（用于研究食区域及轨道长期演化）；我们还申请观测时间，以确认通过对密近双星（close binary）中脉冲星敏感的代码重新处理数据所得到的候选体。