Early Photometry of the Type IIP supernova SN 2013ej
ATel #5466; M. Lee (Taipei First Girls' High School), K. L. Li, J.-W. Wang, A. K.H. Kong (National Tsing Hua U.), H. B. Liu (ASIAA), H.-J. Huang (National Taiwan U. & ASIAA), Y.-H. Huang (U. of Chicago), Y.-M. Lin, K.-C. Yang (TFGHS), on behalf of the Taipei First Girls' High School High Scope Program
on 13 Oct 2013; 07:22 UT
Credential Certification: Albert Kong (firstname.lastname@example.org)
Subjects: Optical, Supernovae
We report an early photometric observation of the Type IIP supernova SN 2013ej taken 15 hours before the official discovery (CBET #3606). We observed the field of M74 on 2013 July 24.80 - 24.83 UT using the 1m telescope at the Lulin Observatory in Taiwan. The supernova 2013ej was clearly detected in our multi-color observations. By comparing with the USNO and GSC2.3 catalogs, we derived the following optical (B, V, and R) photometry: B=13.8, V=14.0, and R=14.3.
The observations were taken under unstable weather condition and we estimated the uncertainties as ~0.2 mag. We note that SN 2013ej was also seen (but without photometry) in a pre-discovery image taken by C. Feliciano on 2013 July 24.125 (Bright Supernovae web site). The supernova was not seen by the All Sky Automated Survey for SuperNovae (ASAS-SN) on 2013 July 23.54 with a detection limit of V > 16.7 (ATel #5237).
The observation is part of an observing training program at Taipei First Girls' High School. This project is funded by the National Science Council of Taiwan as part of the High Scope Program through grants NSC 101-2514-S-007-002 and NSC 101-2514-S-577-001.
Pre-discovery image of SN 2013ej