Monday, March 16, 2015

Bright Nova in Sgr - (PNV J18365700-2855420)

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible bright Nova in Sgr (TOCP Designation: PNV J18365700-2855420) we performed some follow-up of this object remotely through a 0.61-m f/6.5 astrograph + CCD) of  iTelescope network (MPC Code  U69 - Auberry, California - USA).

On our images taken on March 16.5, 2015 we can confirm the presence of an optical counterpart with R-CCD magnitude 5.9 at coordinates:

R.A. = 18 36 56.85, Decl.= -28 55 40.0 (equinox 2000.0; UCAC-4 catalogue reference stars).

This nova has been discovered by John Seach, Chatsworth Island, NSW, Australia,  in three images (limiting magnitude 11.0) taken on Mar. 15.634 UT with a digital SLR camera (+ 50-mm-f.l. f/1.0 lens).

Our wide-Field colour image of Nova Sagittarii 2015 No. 2. Details on the caption. Click on the image for a bigger version.

Click on the thumbnail below to see the full wide-field frame with the nova at the center.

Our annotated confirmation image. Click on it for a bigger version.

An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1996). Our image was obtained when the object was only about +15 degree on the horizon. Click on the thumbnail below for a bigger version:

According to the Atel #7230 "an optical spectrum of PNV J18365700-2855420 (see CBAT TOCP) was obtained using the FRODOspec spectrograph on the Liverpool Telescope at 2015 March 16.27 UT. The spectrum shows strong Balmer series emission exhibiting P Cygni profiles with velocities of ~2800 km/s. Numerous Fe II emission lines (also with P Cygni profiles) are also seen, along with O I, Si II and Mg II features. This confirms that PNV J18365700-2855420 is a bright classical nova of the Fe II spectral type"

by Ernesto Guido & Nick Howes

No comments: