arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新，休息一下吧，周末愉快~~
arXiv 1003.2336astro-ph.SR
收藏

新星V4743 Sgr X射线光变曲线中0.75 mHz特征的多频性质

Multifrequency nature of the 0.75 mHz feature in the X-ray light curves of the nova V4743 Sgr

Andrej Dobrotka, Jan-Uwe Ness

备注：
17 pages, 22 figures, 7 tables, accepted for publication in MNRAS
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

我们提出了8个X射线光曲线和一个光学/紫外光曲线的新星V4743 Sgr（2002年）的CHANNEL和XMM采取爆发后的天：50（早期硬发射阶段），180，196，302，371，526（超软源，SSS，阶段），742和1286（静态发射阶段）的时间分析。我们研究了多频性质和时间演化的主峰在~0.75兆赫使用标准的Lomb-Scargle方法和2-D正弦拟合方法。在第180天和第196天，我们发现了一个双重结构的峰值和它的泛音。在第196天，两个频率更接近，表明两个峰值之间的差异逐渐减小。对于后面的观测，只能检测到单个频率，这可能是由于曝光时间短于两个峰值之间的拍频周期，特别是如果它们移动得更近。在第742天和第1286天的观测时间足够长，可以检测到两个频率，而在第196天发现了差异，但我们确信只发现了一个频率。我们发现振荡频率和振幅的显着变化。我们推导出黑体温度从SSS光谱，和频率和黑体温度的变化的演变表明，0.75兆赫的峰值调制脉动。后来，在核燃烧停止后，信号稳定在一个单一的频率，尽管X射线频率与从XMM机载OM和地面观测获得的光学/紫外频率不同。我们认为，晚的频率是白矮星的旋转和自旋/轨道周期的比例强有力地支持该系统是一个中间极性。

英文摘要：

We present timing analyses of eight X-ray light curves and one optical/UV light curve of the nova V4743 Sgr (2002) taken by CHANDRA and XMM on days after outburst: 50 (early hard emission phase), 180, 196, 302, 371, 526 (super soft source, SSS, phase), and 742 and 1286 (quiescent emission phase). We have studied the multifrequency nature and time evolution of the dominant peak at ~0.75 mHz using the standard Lomb-Scargle method and a 2-D sine fitting method. We found a double structure of the peak and its overtone for days 180 and 196. The two frequencies were closer together on day 196, suggesting that the difference between the two peaks is gradually decreasing. For the later observations, only a single frequency can be detected, which is likely due to the exposure times being shorter than the beat period between the two peaks, especially if they are moving closer together. The observations on days 742 and 1286 are long enough to detect two frequencies with the difference found for day 196, but we confidently find only a single frequency. We found significant changes in the oscillation frequency and amplitude. We have derived blackbody temperatures from the SSS spectra, and the evolution of changes in frequency and blackbody temperature suggests that the 0.75-mHz peak was modulated by pulsations. Later, after nuclear burning had ceased, the signal stabilised at a single frequency, although the X-ray frequency differs from the optical/UV frequency obtained consistently from the OM onboard XMM and from ground-based observations. We believe that the late frequency is the white dwarf rotation and that the ratio of spin/orbit period strongly supports that the system is an intermediate polar.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑