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871.
Buhalqem Nizamdin Ali Esamdin Zhi-Yong LiuNa Wang Cheng-Shi Zhao 《Chinese Astronomy and Astrophysics》2011,35(1):37
Using the 25m radio telescope of the Urumqi Observatory, the strong single pulses of the pulsar PSR J0034-0721 were observed at 1.54 GHz on 6th Aug. 2007. With the technique of single-pulse detection, 116 single pulses with the signal-to-noise ratios of RSN≥5 were detected from the observed data of 1 h. At 1.54 GHz, the signal-to-noise ratios of the detected single pulses are in the range from 5 to 10.5, and the peak flux densities of these pulses are approximately 14∼29 times that of the average pulse (AP), much less than the ratios between the intensities of typical giant pulses and the intensity of AP. The cumulative distribution of the intensities of these pulses is basically a powerlaw distribution with the spectral index α = −4.3 ± 0.4. The detection rates for the pulses of RSN≥5 and RSN≥10 are 3% and 0.08%, respectively. For these pulses, the half-peak width W50 ranges from 1.6 ms to 8 ms, 3.9 ms in average. The phases of the vast majority of the strong single pulses are concentrated around the peak position of AP, but 2 strong pulses of RSN≥8.5 are detected at the phases about 33 ms earlier than the phase of the AP peak. This implies that there probably exist two emission regions of strong pulses, and this is consistent with the previously observed results at 40 MHz and 111 MHz, except that at 1.54 GHz the profile of AP exhibits only one component. 相似文献
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We present an analysis of strong single pulses from PSR J0034-0721. Our observations were made using the Urumqi 25-m radio telescope at a radio frequency of 1.54GHz. A total of 353 strong pulses were detected during eight hours of observing. The signal-to-noise ratios of the detected pulses range from 5 to 11.5. The peak fluxes of those pulses are 17 to 39 times that of the average pulse peak. The cumulative distribution of the signal-to-noise ratios of these strong pulses has a rough power-law distribution... 相似文献
874.
Ye Xu Dong-Rong Jiang Zhi-Yao Yu Xing-Wu Zheng Chuan-Yi Yang Yan-Ping Zhang Chun-Chuan Pei Jun-Mei Ma Jin-Jiang Sun Li-Ming Wang Deng-Rong Lu Jie-Qing Wu Yang Li Cheng-Ming Lei 《中国天文和天体物理学报》2001,(1)
1 INTRODUCTIONA violent molecular outflow is a bajsic component of star formation process. Such outflowsare observed over a wide range of wavelength from the ultraviolet to the radio, resulting fromthe interaction of highly supersonic stellar winds with the alnbiellt material and the windejection takes place in the vicinity of a newly formed star. Outflows are produced by starsof all massess but currellt outflow theories are predominantly based on observations of nearby,low-mass outflow sy… 相似文献
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Li-Cai Deng Heidi Jo Newberg Chao Liu Jeffrey L. Carlin Timothy C. Beers Li Chen Hsu-Tai Lee Carl J. Grillmair Puragra Guhathakurta Zhan-Wen Han Jin-Liang Hou Sebastien Lepine Jing Li Xiao-Wei Liu Kai-Ke Pan J. A. Sellwood Bo Wang Hong-Chi Wang Fan Yang Brian Yanny Hao-Tong Zhang Yue-Yang Zhang Zheng Zheng Zi Zhu 《天体物理学报》2012,(7):735-754