Abstract

UBV (Johnson) and RI (Cousins) magnitudes of field comparison stars for several active quasars and BL Lacertae objects are presented. The comparison stars can be used for photoelectric and CCD monitoring of the variability in brightness and optical-continuum spectral index of these BL Lacs and QSOs. 21 references.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call