GCN Circular 2037

J. Moran, A. Henden, D. Lamb, D. York, M. Nysewander, J. Barentine, J.
Dembicky, C. Graziani, E. Sheldon, R. Soule, M. Bayliss, H. Cheng, C. Cook,
M. Lopez-Morales, D. Reichart, R. McMillan, B. Ketzeback, C. Blacker, and
A. Reese report on behalf of the USNO, ARC, and UNC GRB teams of the FUN
GRB collaboration:

We observed the 14 arcminute diameter error circle of GRB 030324 (Donaghy
et al., GCN 1954
Not found
 
 
, 1955
Not found
 
 
) in BVRci*IcH beginning 2.1 hours after the burst.
Using the field calibration of Henden (GCN 1860
Not found
 
 
) and 2MASS, we report the
following limiting magnitudes:

Start      Start Time Mean Time Filter Integration Limiting  Telescope
Date       Since GRB  Since GRB        Time (sec)  Magnitude
           (hours)    (hours)          x Pointings (3 sigma)
Mar 24.222 2.12       2.12      Ic     300 x 1     20.2      1.0-m USNO
Mar 24.227 2.24       2.24      Rc     300 x 1     21.1      1.0-m USNO
Mar 24.232 2.36       2.96      B      3000 x 1    23.0      1.0-m USNO
Mar 24.240 2.55       3.15      V      1200 x 1    22.4      1.0-m USNO
Mar 24.259 3.00       3.30      H      600 x 4     19.0      1.55-m USNO
Mar 24.332 4.76       5.90      Rc     1478 x 4    19.2      0.6-m MO(1)
Mar 24.345 5.06       5.06      B      600 x 1     22.0      1.0-m USNO
Mar 24.349 5.16       6.22      i*     1200 x 4    23.8 -    3.5-m ARC
                                       + 2400 x 1  24.3(2)
Mar 24.353 5.26       6.49      V      2400 x 1    22.7      1.0-m USNO
Mar 24.358 5.37       6.64      Rc     2400 x 1    22.3      1.0-m USNO
Mar 24.362 5.48       6.60      Ic     2400 x 1    21.6      1.0-m USNO
Mar 24.364 5.52       5.94      H      900 x 4     19.3      1.55-m USNO
Mar 24.389 6.11       6.71      Ic     4200 x 1    16.7(3)   0.2-m PST(4)
Mar 26.477 56.22      56.74     Ic     3600 x 1    21.9(5)   1.0-m USNO

(1) Morehead Observatory telescope
(2) Mosaic pattern results in a limiting magnitude that is 23.8 on the
    sides and 24.3 in the center
(3) 5-sigma limiting magnitude
(4) Pisgah Survey Telescope at the Pisgah Astronomical Research Institute
    (PARI)
(5) Central 11.3' x 11.3'

Using the image subtraction routine ISIS2 (Alard 2000), we find no
transient sources between any of our same-filter images to limiting
magnitudes of B = 22.0, V = 22.4, Rc = 21.1, Ic = 20.2, and H = 19.0
between 2.1 and 3.3 hours after the burst.  Furthermore, we find no
transient sources between our ARC images and SDSS images of this field
taken in March 1999 to a limiting magnitude of i* = 22.2 at 6.2 hours after
the burst.

To these limiting magnitudes, GRB 030324 appears to be a dark burst, not
only at optical wavelengths, but interestingly also at NIR wavelengths.

Alard, C. 2000, A&AS, 114, 363