Palomar Transient Factory: Discovery and Follow-Up of 25 Transients
ATel #2005; R. Quimby (Caltech), M. M. Kasliwal (Caltech), S. B. Cenko (Berkeley), D. Fox (Penn State), A. Gal-Yam (Weizmann), D. A. Howell (LCOGT/UCSB), S. R. Kulkarni (Caltech), N. Law (Caltech), D. Levitan (Caltech), A. Mahabal (Caltech), P. Nugent (LBNL), E. O. Ofek (Caltech), D. Poznanski (UCB/LBNL), and R. Thomas (LBNL), report on behalf of the larger Palomar Transient Factory Collaboration
on 2 Apr 2009; 23:38 UT
Credential Certification: Robert Quimby (quimby@astro.as.utexas.edu)
Subjects: Optical, Cataclysmic Variable, Supernovae, Transient
The Palomar Transient Factory (see ATel #1964) reports the discovery of 25 optical transients with the Palomar Observatory 1.2-m Oschin telescope (+CFH12K camera). Imaging data were obtained on several nights between Mar 17 and Mar 28 with a g-band filter. Transient candidates were identified after subtracting off reference templates constructed from imaging data obtained prior to Mar 12. Spectroscopic follow-up was carried out on Mar 27, 28, 29, 30, and 31 with the 9.2-m Hobby-Eberly Telescope (+LRS), the 5.1-m Palomar Hale (+DBSP) telescope, and the 10.0-m Keck-I (+LRIS) telescope. Below we list the locations of each transient, the UT date in which the transient was first found, and the g-band magnitude at discovery.
Name | RA(J2000) | DEC(J2000) | Date | g-Mag | Offset | z | Class
--------+-------------+-------------+-------------+-------+-------------+------+-------
PTF09k | 12 26 17.84 | +48 26 49.5 | Mar 17.1880 | 20.86 | 5.3"W,6.3"N | 0.19 | Ia
PTF09o | 04 05 02.73 | +73 24 54.2 | Mar 17.1343 | 18.54 | N/A | | (CV?)
PTF09x | 13 21 45.15 | +42 33 06.2 | Mar 21.3851 | 20.18 | 0.8"W,1.2"N | 0.25 | Ia
PTF09y | 11 16 34.27 | +03 32 02.8 | Mar 21.1860 | 20.06 | 0.2"W,2.1"N | 0.19 | SN?
PTF09z | 11 54 42.23 | +55 18 10.7 | Mar 21.4275 | 20.12 | 0.1"W,0.4"N | 0.19 | Ia
PTF09aa | 11 33 20.71 | -09 24 40.3 | Mar 21.1961 | 18.97 | 0.0"W,0.2"N | 0.12 | Ia
PTF09ab | 09 22 15.69 | +45 44 53.4 | Mar 21.3599 | 19.49 | 0.0"E,0.1"N | 0.17 | Ia
PTF09ac | 12 24 35.31 | +47 14 16.8 | Mar 21.4350 | 19.17 | 6.1"W,1.2"N | 0.16 | Ia
PTF09ad | 11 03 06.64 | +50 09 36.3 | Mar 21.4313 | 19.75 | 0.6"W,1.4"N | 0.20 | Ia
PTF09aj | 09 45 30.46 | +06 32 25.0 | Mar 21.2155 | 17.81 | 0.2"W,1.5"N | 0.09 | Ia
PTF09as | 12 59 15.85 | +27 16 41.3 | Mar 25.1642 | 19.08 | 1.7"W,5.5"N | 0.19 | Ia
PTF09av | 09 15 12.73 | +19 05 46.3 | Mar 25.1522 | 20.24 | 2.0"W,2.9"S | 0.22 | Ia
PTF09aw | 14 15 19.36 | +16 25 14.0 | Mar 25.2625 | 19.74 | 4.7"W,4.5"S | 0.17 | Ia
PTF09bc | 10 51 08.55 | +74 05 23.2 | Mar 20.2834 | 20.51 | 3.9"E,1.9"N | 0.18 | Ia
PTF09bd | 08 07 29.72 | +15 34 41.8 | Mar 20.1407 | 16.87 | N/A | | CV
PTF09be | 14 10 18.54 | +16 53 38.8 | Mar 26.2304 | 18.98 | 4.7"E,3.9"N | | ?
PTF09bf | 10 43 29.16 | +06 14 05.4 | Mar 26.1674 | 17.30 | N/A | | (CV?)
PTF09bh | 12 24 39.20 | +08 55 59.2 | Mar 28.4155 | 20.51 | 1.6"W,0.8"N | 0.18 | Ia
PTF09bi | 11 46 50.12 | +11 47 55.3 | Mar 25.1613 | 19.56 | 2.6"W,0.7"S | 0.11 | II?
PTF09bj | 11 18 06.46 | +12 53 43.1 | Mar 25.1627 | 18.05 | 0.1"E,1.3"N | 0.14 | Ia
PTF09bw | 15 05 01.97 | +48 40 03.9 | Mar 28.4039 | 20.29 | 0.8"W,0.7"N | 0.15 | IIn?
PTF09bx | 14 30 50.42 | +35 37 31.4 | Mar 26.2086 | 18.79 | 4.2"E,3.3"S | | (SN?)
PTF09by | 13 29 12.64 | +46 43 27.5 | Mar 26.2509 | 19.28 | 0.2"E,0.9"N | 0.10 | Ia
PTF09ct | 11 42 13.88 | +10 38 54.0 | Mar 27.1606 | 20.30 | 5.6"W,5.2"N | 0.15 | II?
PTF09cu | 13 15 23.15 | +46 25 09.4 | Mar 26.2509 | 17.91 | 7.5"W,3.9"S | 0.06 | II
PTF09o was detected at the same location in two visits separated by 2 hours, but we do not have further subtractions of this field. We performed a spectroscopic observation at this location on Mar 31 with Keck/LRIS, but no source was detected. This significant fading suggests a dwarf nova. Similarly, PTF09bf rose by more than 3 magnitudes from Mar 25th to the 26th but faded away by our P200/DBSP observations on Mar 30. We suggest this is a dwarf nova as well. We have not spectroscopically confirmed PTF09bx; however, from its association with a
SDSS galaxy (z=0.03), we infer that this is a SN. Spectra of PTF09be show a nearly featureless blue continuum. PTF09as was independently discovered by
CRTS.