HST/WFC3 Ultraviolet Observations of AT2018cow
ATel #11921; C. D. Kilpatrick, R. J. Foley, C. Rojas-Bravo (UCSC), M. R. Drout, A. L. Piro (Carnegie Observatories), S. J. Smartt, K. Maguire, M. Magee, S. Prentice (Queen's University Belfast), A. Rest (STScI)
on 6 Aug 2018; 21:08 UT
Credential Certification: Charles Kilpatrick (cdkilpat@ucsc.edu)
Subjects: Optical, Ultra-Violet, Supernovae, Transient
On UT 2018 Aug 6.4, we obtained imaging of AT2018cow (ATel #11727; Prentice et al. 2018, arXiv:1807.05965; Rivera Sandoval et al. 2018, arXiv:1807.06369; Perley et al. 2018, arXiv:1808.00969) in four ultraviolet bands (F218W, F225W, F275W, F336W) with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST; Program 15600; PI Foley). Aligning these images to ground-based imaging of AT2018cow at peak brightness, we clearly detect the transient source in all four bands. From these images, we find that the transient had brightness (Vega mag):
F218W = 19.3 +/- 0.1 mag
F225W = 19.2 +/- 0.1 mag
F275W = 18.9 +/- 0.1 mag
F336W = 19.1 +/- 0.1 mag
Additional HST/WFC3 imaging is scheduled.
