摘要
利用南山基地25 m射电望远镜在1.54 GHz频段对脉冲星PSRJ0034-0721强单个脉冲进行了观测.使用单脉冲探测方法,从1 h观测数据中探测到116个信噪比R_(SN)N≥5的单个脉冲信号.在1.54 GHz频段探测到的单个脉冲R_(SN)从5到10.5,峰值流量约是平均脉冲峰值流量的14～29倍,远小于典型巨脉冲强度与其平均脉冲强度的比.这些脉冲的强度累积分布基本符合幂律谱,拟合得到谱指数α=-4.3±0.4.本次观测对R_(SN)≥5的单个脉冲探测率为3%,对R_(SN)≥10的单个脉冲探测率约为0.08%.这些脉冲的半峰线宽(W_(50))从1.6到8 ms,平均为3.9 ms.探测到的绝大多数强单脉冲发射相位集中分布在平均脉冲轮廓的峰值相位处,但也探测到两个R_(SN)>8.5的强脉冲相位提前平均脉冲轮廓峰值相位33 ms左右,表明强脉冲发射区可能有两个,符合前人在40 MHz和111 MHz频段的观测结果,但1.54 GHz频段的平均脉冲轮廓只显示一个成份.
Using the Urumqi 25 m radio telescope on Aug. 6th 2007, the analysis results of strong single pulses of PSR J0034-0721 observed at 1.54 GHz are reported. 1-hr data is collected. Using the single-pulse searching method, 116 strong pulses of PSR J0034-0721 with signal-to-noise ratios （RSN） above 5a threshold are detected. The RsN values of the detected pulses are from 5 to 10.5 and the peak fluxes of these pulses are approximately 14 to 29 times that of the average pulse （AP）. However, these values are much less than those of the classical giant pulses. The cumulative distribution of the RSN of these pulses has roughly a power-law distribution with a slope of -4.3±0.4. The detectivity of the pulses with RSN≥5 and RSN≥10 are 3% and 0.08%, respectively. The half peak line breadths W50 of these pulses range from 1.6 ms to 8 ins, with an average value of 3.9 ms. Most of the pulses cluster in the narrow region centering at the peak of the AP. However, two strong pulses with RSN〉8.5 are detected at the phase about 33 ms earlier than the phase of the AP peak. This may indicate that there are two strong-pulse emitting regions.
出处
《天文学报》
CSCD
北大核心
2010年第3期253-262,共10页
Acta Astronomica Sinica
基金
国家自然科学基金(10973026)
西部之光-联合学者(LHXZ200602)资助项目
关键词
恒星
中子
脉冲星
个别
stars
neutron, pulsars
individual
