2004/07/31 by T. Sumi, P. R. Wozniak, P. R. Woźniak +15 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Gamma-ray bursts and supernovae #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2004.08453.x
published as Mon.Not.Roy.Astron.Soc. 356 (2005) 331-335 · 6 pages, 3 figures, MNRAS in press
arxiv created 2004/10/02 · openalex publication_date 2004/12/16 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present 97 QSO candidates in 48 Galactic bulge fields of the Optical Gravitational Lensing Experiment II (OGLE-II) covering ∼11 deg2, which are selected via their variability. We extend light curves of variable objects which were detected in a 3-yr baseline in the OGLE-II variable star catalogue to fourth year. We search for objects that are faint (16 < I0 < 18.5) and slowly variable over 4 yr in this catalogue by using the variogram/structure function. Finding the QSOs in such stellar-crowded and high extinction fields is challenging, but should be useful for the astrometric reference frame. Spectroscopic follow-up observations are required to confirm these QSO candidates. Follow-up observations are being prepared for four of these fields (BULSC1, 2, 32 and 45). Follow-up observations for other fields are strongly encouraged. The complete list and light curves of all 97 candidates are available in electronic format at .