New nova candidate in the outer M81 disk

ATel #10312; M. Henze (CSIC-IEEC), H. Meusinger, C. Pohl (TLS), S. C. Williams (Lancaster), M. J. Darnley (LJMU), A. Kaur, D. H. Hartmann (Clemson), G. Sala, J. Jose, J. Figueira (UPC-IEEC), M. Hernanz (CSIC-IEEC), K. Hornoch (Ondrejov), A. W. Shafter (SDSU)
on 22 Apr 2017; 20:32 UT
Credential Certification: Martin Henze (henze@ice.cat)

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The M81 nova monitoring collaboration reports a potential nova in the outer regions of the M81 galaxy on a stacked 2x120s R-band image taken on April 20.866 UT with the 2-m Alfred-Jensch-Telescope of the Tautenburg observatory (TLS). The object is clearly detected in both individual exposures at a position of RA = 09:56:08.39, Dec = +68:56:33.9 (J2000; 1 sigma uncertainty 0.3 arcsec). It might have been already faintly present on a similar stack with the same instrument in the previous night, but nothing significant was detected. No object is visible down to about R = 22.5 in a deep stack of images obtained with the same instrument throughout January 2017 or in archival SDSS data. Here we list the observing dates and corresponding photometry:

 
Date [UT]      | Mag   | Err  | Filter  | Telescope 
2017-04-19.909 | ≳22.0 | 0.3  | R       | TLS 
2017-04-20.866 |  21.7 | 0.3  | R       | TLS 

The 2-m TLS of the Tautenburg observatory, Germany, was operated in Schmidt camera mode using a 2k x 2k CCD with a 0.7 x 0.7 deg field of view. The TLS photometry was calibrated using the SDSS DR7 photometry catalogue.