activity
19982000
collaborators

7 papers

astro-ph2000

The variability analysis of PKS 2155-304

J. H. Fan, R. G. Lin

In this paper, the post-1977 photometric observations of PKS 2155-304 are compiled and used to discuss the variation periodicity. Largest amplitude variations (; $ΔB…

astro-ph1999

The polarization and beaming effect for GRBs

K. S. Cheng, J. H. Fan, Z. G. Dai

Both observations and theoretical models suggest that the emissions in gamma-ray bursts (GRBs) and the afterglows are beamed. We argue that the recent polarization measured in the…

astro-ph1999

Basic properties of Gamma-ray loud blazars

K. S. Cheng, J. H. Fan, L. Zhang

In this paper, a method is proposed to determine the basic properties of -ray loud blazars, among them the central black hole mass, M, the Doppler factor, , the propagation a…

astro-ph1999

Polarization and Variations of BL Lacertae Objects

J. H. Fan, K. S. Cheng, L. Zhang

BL Lacertae objects are an extreme subclass of AGNs showing rapid and large-amplitude variability, high and variable polarization, and core-dominated radio emissions. If a strong b…

astro-ph1999

Long-term infrared variation of 3C 279 and 4C 29.45

J. H. Fan

In this paper, the historical infrared (JHK) data compiled from 22 publications are presented for 3C279 and 4C29.45. Relation between color index and magnitude and between color-co…

astro-ph1998

Long-term Variation of AGNs

J. H. Fan, G. Z. Xie, G. Adam +5

In this paper, we will discuss the long-term variations in the optical and the infrared bands of some AGNs. It is interesting to note that the reported periods of AGNs are of the s…