V4334 Sagittarii
Abstract
W. Liller, Instituto Isaac Newton, Vina del Mar, Chile; M. Janson, Groningen University; H. W. Duerbeck, Muenster University; and A. van Genderen, Leiden University, report that this object (cf. IAUC 6718) has faded by almost 2 mag since last November, indicating that the predicted dust formation (Duerbeck et al. 1997, A.J. 114, 1657) from the presumed final helium flash has begun. During 1997 Mar.-Nov., the star was between V = 10.75 and 11.0. Subsequent V magnitudes by Liller (L; 0.2-m telescope) and by Janson (J; ESO Dutch 0.9-m telescope): 1997 Nov. 21.02 UT, 10.76 (L); 1998 Feb. 9.37, 11.96 (L); 10.35, 11.90 (L); 14.38, 12.73 (J); 15.38, 12.75 (J); 17.36, 12.74 (J). The star has also become generally redder; between 1997 Sept. 14 and 1998 Feb. 15, U-B changed from +0.83 to +1.12, B-V from +1.66 to +1.51, V-R from +1.11 to +1.71, and V-i (Gunn i) from 2.08 to 2.86. Multicolor optical monitoring is being carried out, and infrared photometry is encouraged.
- Publication:
-
International Astronomical Union Circular
- Pub Date:
- February 1998
- Bibcode:
- 1998IAUC.6825....2L