GCN Circular 340

H. Pedersen, J. Hjorth, B. L. Jensen (Copenhagen), A. O. Jaunsen (Oslo), 
R. Falomo (Padova), I. Burud (Liege), M. I. Andersen, H. Korhonen, 
H. Schwarz (NOT), E. Costa, L. Piro (IAS/CNR, Rome), and, 
E. Pian (Ist.TeSRE, Bologna), report:

We have used the ALFOSC instrument (field 6' x 6') at the NOT, La Palma,
to acquire three 4-minute R-band exposures of the position reported
from BeppoSAX (Gandolfi et al., IAU Circular No. 7174). 

The exposures were taken 1999 May 20.898 - 20.910 UT. The seeing was 0.7". 

Comparison to the DSS-2 did not reveal any new object. Comparison between 
the three exposures internally did not reveal any variable object. 

One object drew attention during our inspection of the images:
this is the SN-like configuration of an apparently unresolved object 
1.6" east, 0.5" south of a galaxy (which, in turn, is well visible on 
the DSS). The object may well be due to a surface brightness concentration 
in the said galaxy, or the chance superposition of a galactic star.

To test the visual impression, we have analyzed the images, using 
the deconvolution technique applied in GCN 320
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 ; unfortunately, the
low s/n ratio does not allow any clear distinction between resolved
and not resolved models.

The position of the object of concern is 
R.A. 08 h 35 m 52.44 s, Decl. +51o 18' 46.9" (J2000); uncertainty 0.5".
Its brightness is estimated at m(R) = 22.0 +- 0.5.  No variability is
indicated. For the galaxy, we find m(R) = 19.75 +- 0.3. The photometric
measurements stem from a standard calibration of the instrument, for
which m(R) = 16.71 for an object at 
R.A. 08 h 35 m 52.88 s, Decl. +51o 18' 06.2" (J2000). 

A 2' by 2' section of the sum-image, centered on the object is placed on 

http://www.astro.ku.dk/~holger/g/XRT990520/imag.fits . 

A gif-version will be provided later.

Before any use of this digital data in publications, please consult with us.