NOVA SCORPII 2011

CBET circular No. 2735, issued on June 03, 2011, announces the discovery by John Seach (Australia) of a possible nova (mag 9.5) on three CCD images (limiting mag 11.0) taken on June 1.40 UT with a digital SLR camera (+ 50-mm-f.l. f/1.2 lens + orange filter).

We performed some follow-up of this object remotely with the GRAS RCOS 32-cm f/6.3 telescope at Officer, Australia. On our images taken on June 02.4, 2011 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 9.4 (USNO-B1.0 Catalogue reference stars) at coordinates:

R.A. = 16 55 09.46, Decl.= -38 38 04.5

(equinox 2000.0; USNO-B1.0 catalogue reference stars).

Our confirmation image (click for a bigger version):

Below you can see an animation showing a comparison between our confirming image and the archive POSS2/UKSTU plate (R Filter - 1995). Click on the thumbnail below for a bigger version:

CBET circular No. 2735 also reports that A. Arai, T. Kajikawa, and M. Nagashima, Kyoto Sangyo University, performed low-dispersion optical spectroscopic observations (range 400-750 nm; R about 600) of this transient on June 2.68 UT using the 1.3-m Araki telescope (+ LOSA/F2) under a hazy sky. The spectrum shows a broad H-alpha (FWZI about 4600 km/s) with an asymmetric profile and O I (777.4 nm) on a highly-reddened continuum. No visible He or Fe II lines exist in the spectrum. These features suggest that the object is a classical nova in outburst with high interstellar reddening.

(Credit: A. Arai, T. Kajikawa, and M. Nagashima)

by Ernesto Guido and Giovanni Sostero

Possible Nova in Scorpius

CBET circular No. 2262, issued on April 26, 2010, announces the discovery by K. Nishiyama & F. Kabashima (Japan) of another possible nova (mag 8.6) on two 40-s unfiltered CCD frames (limiting magnitude 13.1) taken around Apr. 25.788 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera). The same CBET reports indipendent discovery by H. Nishimura & T. Kojima.

We performed some follow-up of this object remotely through a 0.25-m, f/3,4 reflector + CCD, from GRAS Observatory (near Mayhill, NM).

On our images taken on April 26.4, 2010 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 8.2 (UCAC2 Catalogue reference stars) at coordinates:

R.A. = 16 55 13.17, Decl.= -38 03 47.8

(equinox 2000.0; UCAC2 catalogue reference stars).

Our confirmation image:

This is an animation showing a comparison between our image and the archive DSS plate (R Filter - 1995). Click on it for a bigger version.

UPDATE - MAY 06, 2010

According to IAUC circular No. 9142, a low-dispersion spectrum (range 420-850 nm, resolution about 500) of this object, taken by K. Kinugasa, H. Takahashi, and O. Hashimoto on Apr. 29.745 UT with the GAO 1.5-m telescope (+ GLOWS), shows broad (FWHM about 4000 km/s) Balmer and O I (777.4-, 822.7-, and 844.6-nm) emission lines. The features indicate that the object is a He/N nova in a declining phase.

The permanent GCVS designation V1311 Sco has been assigned to this nova.

V1311 SCORPII = NOVA SCORPII 2010 No. 2

by Ernesto Guido and Giovanni Sostero

Possible Nova in Scorpius

Following the posting on the Central Bureau's unconfirmed-objects webpage about a possible nova in Sco, on February 22.8, 2010 we performed some follow-up of this object remotely through through a 0.40-m, f/3.8 reflector + CCD, from GRAS Observatory (Moorook, Australia).

On our images we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 10.1 (UCAC2 Catalogue reference stars) at coordinates:

R.A. = 17 06 07.50, Decl.= -37 14 27.7
(equinox 2000.0; UCAC2 catalogue reference stars)

Our confirmation image:

This is an animation showing a comparison between our image and thearchive DSS plate:

Spectroscopic observations are required to confirm the real nature of this transient.

UPDATE - February 24, 2010

According to Cbet No 2183 this transient in Scorpius has been discovered by Koichi Nishiyama and Fujio Kabashima (Japan) on two 40-s unfiltered CCD frames (limiting magnitude 12.7) taken around Feb. 20.857 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera).

On Cbet 2186 (issued on February 23), K. Ayani (BAO) reported that a low-resolution spectrum (range 400-800 nm; resolution 0.5 nm at H-alpha) of the probable nova was obtained with the BAO 1-m telescope on Feb. 23.88 UT. This shows prominent H-alpha emission with P-Cyg absorption upon a red continuum. These features show that the new object is a "Fe II"-type nova.

The transient is officially NOVA SCORPII 2010.

by Ernesto Guido and Giovanni Sostero