A flattening in the optical light curve of SN 2002ap
A flattening in the optical light curve of SN 2002ap
复制标题
SN 2002ap 的光学光曲线变平
DOI：
--
复制
发表时间：
2002
期刊：
影响因子：
--
通讯作者：
J. Pandey
中科院分区：
文献类型：
--
作者：
S. Pandey;G. Anupama;R. Sagar;D. Bhattacharya;D. Sahu;J. Pandey
本文介绍了2002年2月6日至3月23日期间获得的Ic型超新星SN 2002ap的UBV RcIc宽波段光学测光结果。结合这些数据与已发表的，一般的光变曲线的发展进行了研究。估算了峰值亮度和峰宽的时间和亮度。在B极大值后约30天，光学光变曲线有一个平坦化。在U、B、V、Rc和Ic通带中，平坦化前的通量下降率分别为0.127±0.005、0.082 ± 0.001、0.074±0.001、0.062±0.001和0.040±0.001 mag day −1，而在所有通带中，平坦化后的相应值约为0.02 mag day −1。SN 2002ap的最大亮度MV = 17.2等，与Ic型超新星SN 1997ef相当，但比Ic型超新星SN 1998bw要暗。峰值亮度显示出一个约0.06 M的镍质量的喷射。我们还提出了在早期阶段获得的低分辨率光谱。SiII吸收最小值表明光球速度在6天内从21，360 km s −1下降到10，740 km s −1。
We present the UBV RcIc broad band optical photometry of the Type Ic supernova SN 2002ap obtained during 2002 February 06 – March 23 in the early decline phases and also later on 2002 15 August. Combining these data with the published ones, the general light curve development is studied. The time and luminosity of the peak brightness and the peak width are estimated. There is a flattening in the optical light curve about 30 days after the B maximum. The flux decline rates before flattening are 0.127±0.005, 0.082±0.001, 0.074±0.001, 0.062±0.001 and 0.040±0.001 mag day −1 in U, B, V , Rc and Ic passbands respectively, while the corresponding values after flattening are about 0.02 mag day −1 in all the passbands. The maximum brightness of SN 2002ap MV = 17.2 mag, is comparable to that of the type Ic 1997ef, but fainter than that of the type Ic hypernova SN 1998bw. The peak luminosity indicates an ejection of � 0.06 M⊙ 56 Ni mass. We also present low-resolution optical spectra obtained during the early phases. The SiII absorption minimum indicates that the photospheric velocity decreased from � 21,360 km s −1 to � 10,740 km s −1 during a period of � 6 days.