Radio non-detection of SSS130101:122222-311525

ATel #4785; Leonid Petrov (Astrogeo Center), Philip Edwards (CSIRO, Australia), Mark Wieringa (CSIRO, Australia), Ashish Mahabal (Caltech), Andrwe Drake (Caltech), George Djorgovski (Caltech)
on 5 Feb 2013; 03:02 UT
Credential Certification: Ashish Mahabal (aam@astro.caltech.edu)

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We have observed in radio and find no evidence of detection for the transient SSS130101:122222-3115250. The Cataclysmic Variable with a ROSAT X-ray match had seemed intriguing due to a possible NVSS match. (Drake et al., ATel #4699; Levato et al., ATel #4700; Marsh et al., ATel #4704; Li et al., ATel #4708; Kuulkers et al., ATel #4716, and Neustroev et al., ATel #4744). We report non-detection of this source at 5.5 and 9.0 GHz at a 60 micro-Jy level (3 sigma). The radio non-detection is broadly consistent with CVs not being radio emitters. Details of observations are given below.

A first epoch ATCA observation was obtained on January 7 (UT) using the east-west EW352 array for two-hours, with two 2-GHz wide bands from the Compact Array Broadband Backend (Wilson et al. 2011, MNRAS, 416, 832) centered on 5.5 and 9.0 GHz. The standard primary flux density calibrator, PKS 1934-638, was used for flux density calibration. A phase calibrator near the target position was observed for 2 minutes every 20 minutes and these phase solutions applied to the target position. The resulting images are of low quality due to the limited (u,v) coverage, with no detection of a source at either frequency at the optical position. The 3-sigma upper limit at the optical position is about 100 micro-Jy at both frequencies.

A second epoch ATCA observation was made on January 17 (UT), in a 750m east-west array, with other parameters of the observing mode staying unchanged. Two ~1-hr observations were separated by ~6 hrs resulting in improved (u,v) coverage. The resulting beam sizes were 5 arcsec x 8 arcsec at 5.5 GHz, and 3 arcsec x 5 arcsec at 9.0 GHz. The (1-sigma) noise levels in the images were 18 micro-Jy at 5.5 GHz and 22 micro-Jy at 9.0 GHz. Again, no source was detected at the position of the optical transient, with 3-sigma upper limits of 54 and 66 micro-Jy respectively.

Detailed data analysis and radio images of the area in the vicinity of SSS130101:122222-311525 are available at http://astrogeo.org/petrov/discussion/1219-309/