Infrared observations of the field of V4643 Sgr = Nova Sagittarii 2001
ATel #4405; W. P. Varricatt (Joint Astronomy Centre, Hilo, HI, USA), D. P. K. Banerjee, N. M. Ashok (Physical Research Laboratory, Ahmedabad, India)
on 21 Sep 2012; 02:56 UT
Credential Certification: Watson Varricatt (w.varricatt@jach.hawaii.edu)
Subjects: Infra-Red, Nova
The Classical Nova V4643 Sagittarii (Nova Sagittarii 2001) was discovered in outburst on 2001, Feb. 24.369 (Liller, W.; Broughton, J. 2001, IAUC, 7589, 1). A detailed optical and near-IR study of this object can be seen in Ashok, N. M. et al. 2006, MNRAS, 368, 592.
We observed the field of V4643 Sgr to search for its progenitor. Observations were performed during the UKIDSS backup time on two epochs, with the 3.8-m United Kingdom Infrared Telescope (UKIRT) and the UKIRT Wide Field Camera (WFCAM), using the near-IR filters Z, Y, J, H and K (effective wavelengths: 0.8717, 1.0305, 1.2483, 1.6313 and 2.2010 microns respectively). The details of the observations are given in the table below.
The field is very crowded. We do not see any near-IR source at the discovery coordinates of the Nova (RA=17:54:40.46, Dec=-26:14:15.2; Liller & Broughton, 2001). The source closest is at RA=17:54:40.419, Dec=-26:14:15.49 (J2000) in our images. The near-IR magnitudes (in the UKIRT-WFCAM photometric system) of this source are given in the table below. This object is offset 0.68 arcsec from the coordinates of the nova and is the same as the source #0600-29446361 in the USNO-A2 Catalogue reported by Samus N. N. 2001, IAUC, 7591, 2. Spectroscopic observations are warranted to confirm its nature and to learn if this is the the progenitor of the nova, or is just a field star.
A JHK colour composite of a 2'X2' field around the location of V4643 Sgr, constructed from the images obtained on 20120322, can be seen at http://www.jach.hawaii.edu/UKIRT/publications/SC/V4643Sgr_field_2arcmin_ATel_20120920.jpg
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UTDATE | UT |Filt| mag | error
yyyymmdd | hh:mm:ss | | |
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20120321 | 15:12:37 | Z | 13.593 | 0.020
20120321 | 15:29:04 | J | 12.887 | 0.020
20120321 | 15:35:54 | H | 12.467 | 0.010
20120321 | 15:40:05 | K | 12.092 | 0.010
20120322 | 15:08:46 | Z | 13.594 | 0.010
20120322 | 15:16:59 | Y | 13.416 | 0.010
20120322 | 15:25:21 | J | 12.904 | 0.010
20120322 | 15:32:12 | H | 12.482 | 0.010
20120322 | 15:36:35 | K | 12.095 | 0.010
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UKIRT is funded by the UK-STFC. The data reduction and distribution are performed by the CASU and WFAU respectively. We thank Tim Carroll for carrying out the observations.
