Discovery of an Apparent Nova in M81

ATel #4968; K. Hornoch (Astronomical Institute, Ondrejov, Czech Republic), O. Vaduvescu (ING, La Palma, Spain), A. Gonzalez (ING, La Palma and University of La Laguna, Tenerife, Spain)
on 11 Apr 2013; 10:08 UT
Credential Certification: Allen W. Shafter (aws@nova.sdsu.edu)

Tweet

We report the discovery of an apparent nova in the M81 galaxy on a co-added 2000-s narrow-band H-alpha CCD image taken with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma in ~1.4" seeing on Apr. 5.946 UT. The new object is visible on individual 400-s frames and well visible on the co-added image (see the finding chart linked below), but is not present on numerous narrow-band H-alpha archival images from the INT down to limiting magnitude as faint as H-alpha = 21.7. We also obtained R (on Apr. 5.946) and I-band (on Mar. 25.949) images that helped us to classify the object. Strong H-alpha emission together with relative faintness in the R and I bands is consistent with evolved nova phenomenon and supports the classification of the object as a nova.

The new object designated PNV J09552925+6904045 is located at R.A. = 9h55m29s.25, Decl. = +69o04'04".5 (equinox 2000.0), which is 21.0" west and 9.4" north of the center of M81.

The photometry of the PNV J09552925+6904045 (this ATel), PNV J09553917+6902390 (ATel #4894), PNV J09552647+6903073, PNV J09553974+6905219, and PNV J09560368+6859586 (ATel #4844), PNV J09555123+6901482 (ATel #4794), and PNV J09555177+6902549 (ATel #4630) obtained from the INT images mentioned above is summarized in the following table:

 
  TOCP designation      CBAT designation    H-alpha mag        R mag        I mag 
 
PNV J09552925+6904045    M81N 2013-04a?    19.5 +/- 0.15    21.1 +/- 0.3    > 21.0 
PNV J09553917+6902390    M81N 2013-03a?    20.5 +/- 0.15       > 22.3       > 21.9 
PNV J09560368+6859586    M81N 2013-02d?    21.6 +/- 0.25       > 22.3       > 21.9 
PNV J09553974+6905219    M81N 2013-02c?    21.0 +/- 0.2        > 22.3       > 21.9 
PNV J09552647+6903073    M81N 2013-02b?    20.7 +/- 0.15       > 22.3       > 21.9 
PNV J09555123+6901482    M81N 2013-02a?       > 22.5           > 22.3       > 21.9 
PNV J09555177+6902549    M81N 2012-12a?    22.8 +/- 0.4        > 22.3       > 21.9 
 

This work is based on observations made with the Isaac Newton Telescope (INT) operated on the island of La Palma by the Isaac Newton Group (ING) in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias (IAC).

Finding chart