Mode change characteristics of PSR J0826+2637
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摘要:利用FAST在中心频率为1.25 GHz的观测数据,分析了PSR J0826+2637的单脉冲能量分布和调制特性,发现存在新的模式变换,并探讨了不同模式的平均脉冲轮廓和偏振特性.结果显示:在B模式中存在强、弱2种模式,弱模式中存在脉冲消零(PN)现象, 脉冲消零比(NF)为2.7%;在强、弱2种模式中,中间脉冲的偏振结果差异较小,而主脉冲的变化较大.PSR J0826+2637的模式变换特性很难用现有的模型来解释.
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关键词:
- 脉冲星/
- 模式变换/
- 偏振/
- PSR J0826+2637
Abstract:The FAST observation data at center frequency of 1.25 GHz are used to analyze energy distribution and modulation characteristics of single pulse of PSR J0826+2637.A new mode change is found, average pulse profile and polarization characteristics of different modes are discussed.Strong and weak modes are present in B mode, a PN phenomenon is found in weak mode, with NF of 2.7%.In both strong and weak modes, polarization results of inter-pulse are slightly different, while the main pulse changes greatly.The mode change characteristics of PSR J0826+2637 are difficult to explain with existing models.-
Key words:
- pulsars/
- mode change/
- polarization/
- PSR J0826+2637
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表 1不同模式的偏振和轮廓参数
模式 L/I V/I $ \left|V\right| $/I W50 W10 % (°) 所有脉冲 所有成分 21.10±0.01 1.61±0.02 2.63±0.01 — — 主脉冲 20.95±0.01 1.62±0.01 2.67±0.01 3.95±0.02 9.06±0.19 中间脉冲 30.43±0.53 1.23±0.67 0.08±0.41 — — 强模式 所有成分 23.26±0.01 1.10±0.01 2.39±0.01 — — 主脉冲 23.19±0.01 1.12±0.01 2.40±0.01 3.99±0.02 8.70±0.21 中间脉冲 33.01±0.94 −0.76±1.34 0.69±0.80 — — 弱模式 所有成分 16.95±0.03 2.64±0.04 3.55±0.03 — — 主脉冲 16.48±0.02 2.72±0.04 3.67±0.02 3.68±0.07 9.47±0.22 中间脉冲 29.77±0.58 0.43±0.78 0.32±0.45 — — -
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