人马座新星2015#2（V5668 Sgr）尘埃形成和破坏的时间发展：全色研究
The Temporal Development of Dust Formation and Destruction in Nova Sagittarii 2015#2 (V5668 Sgr): A Panchromatic Study
摘要：
我们提出了5-28微米SOFIA预报光谱补充全色X射线通过红外观测的CO新星V5668 Sgr记录的形成和破坏的尘埃在500天后爆发。在1090 K的温度下，爆发后82天，尘埃开始凝结。冷凝温度表明冷凝物是无定形碳。有一个逐渐减少的粒度和粉尘质量在恢复阶段。这里给出的绝对参数值是针对1.2 kpc的假定距离。我们的结论是，如果尘埃是无定形碳，产生的尘埃的最大质量是1.2 x 10-7太阳质量。平均晶粒半径增长到最大值为2.9微米，在720 K的温度下约113天时，壳的视觉光学深度为Tau = 5.4。最大晶粒生长之后，随后是一段时间的晶粒破坏。从第95天到第500天以后，用Swift检测X射线。由热白矮星产生的雨燕X射线计数率在第220天左右达到峰值，当时它的光谱是kT = 35 eV的黑体。温度，加上超软X射线的开启和关闭时间，表明WD的质量为1.1太阳质量。我们表明，X射线通量足以摧毁尘埃。我们的数据表明，尘埃事件后的X射线增亮不是由于尘埃破坏，这肯定会发生，因为尘埃对X射线来说是光学薄的。
英文摘要：
We present 5-28 micron SOFIA FORECAST spectroscopy complemented by panchromatic X-ray through infrared observations of the CO nova V5668 Sgr documenting the formation and destruction of dust during 500 days following outburst. Dust condensation commenced by 82 days after outburst at a temperature of 1090 K. The condensation temperature indicates that the condensate was amorphous carbon. There was a gradual decrease of the grain size and dust mass during the recovery phase. Absolute parameter values given here are for an assumed distance of 1.2 kpc. We conclude that the maximum mass of dust produced was 1.2 x 10-7 solar masses if the dust was amorphous carbon. The average grain radius grew to a maximum of 2.9 microns at a temperature of 720 K around day 113 when the shell visual optical depth was Tau = 5.4. Maximum grain growth was followed by followed by a period of grain destruction. X-rays were detected with Swift from day 95 to beyond day 500. The Swift X-ray count rate due to the hot white dwarf peaked around day 220, when its spectrum was that of a kT = 35 eV blackbody. The temperature, together with the super-soft X-ray turn-on and turn-off times, suggests a WD mass of 1.1 solar masses. We show that the X-ray fluence was sufficient to destroy the dust. Our data show that the post-dust event X-ray brightening is not due to dust destruction, which certainly occurred, as the dust is optically thin to X-rays.
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。
