Swift observation of PS1-12fo (=CSS120121)
ATel #3925; R. Margutti, A. Soderberg, L. Chomiuk, E. Berger, D. Milisavljevic, N. Sanders (Harvard University)
on 14 Feb 2012; 23:52 UT
Credential Certification: Raffaella Margutti (rmargutti@cfa.harvard.edu)
Subjects: Optical, Ultra-Violet, X-ray, Supernovae
PS1-12fo is a spectroscopically confirmed, very luminous supernova with similarities to SN2010gx, lying at redshift z=0.175 (Valenti et al. ATels #2668, #3351; Smartt et al. Atel #3918). A Swift ToO was executed starting from 2012-02-13T16:55:19 UT.
Swift-UVOT observations have been obtained in the 6 optical/UV filters. A source is marginally detected at the SN position in the v, b, u and m2 filters, while it is seen faintly in the w1 and w2 filters. Including possible contamination from the underlying host galaxy, we measure the following preliminary magnitudes (UVOT photometric system Breeveld et al. 2011, arXiv:1102.4717): v= 19.0 +/- 0.2; b= 19.8 +/- 0.2; u= 19.5 +/- 0.2; m2= 20.4 +/- 0.2. Magnitudes are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.068 in the direction of the transient (Schlegel et al. 1998).
Contemporary Swift-XRT observations have been performed (total exposure of 5 ks). No X-ray source is detected at the optical position of the transient, with a 3 sigma upper limit of ~3.2d-3 c/s in the 0.3-10 keV energy band. The Galactic neutral hydrogen column density in the direction of the event is 2.38d20 1/cm2 (Kalberla 2005). Assuming a spectral photon index ~2, this translates into an absorbed flux of ~1.6d-13 erg/s/cm2 (corresponding to a luminosity of ~1d43 erg/s. A luminosity distance of 836 Mpc has been used).
We thank the Swift team for scheduling these ToO observations.
