5 papers · 1 filter
Constraints on the generalized tachyon field models from latest observational data
Rong-Jia Yang, Shuang Nan Zhang, Yuan Liu
We consider constraints on generalized tachyon field (GTF) models from latest observational data (including 182 gold SNIa data, the shift parameter, and the acoustic scale). We obt…
A Cosmology-Independent Calibration of Gamma-Ray Burst Luminosity Relations and the Hubble Diagram
Nan Liang, Wei Ke Xiao, Yuan Liu +1
An important concern in the application of gamma-ray bursts (GRBs) to cosmology is that the calibration of GRB luminosity/energy relations depends on the cosmological model, due to…
Is the anti-correlation between the X-ray variability amplitude and black hole mass of AGNs intrinsic?
Yuan Liu, Shuang Nan Zhang
Aims. Both the black hole mass and the X-ray luminosity of AGNs have been found to be anti-correlated with the normalized excess variance () of the X-ray light curv…
Observe matter falling into a black hole
Shuang Nan Zhang, Yuan Liu
It has been well known that in the point of view of a distant observer, all in-falling matter to a black hole (BH) will be eventually stalled and "frozen" just outside the event ho…
The Lorentz factor distribution and luminosity function of relativistic jets in AGNs
Yuan Liu, Shuang Nan Zhang
The observed apparent velocities and luminosities of the relativistic jets in AGNs are significantly different from their intrinsic values due to strong special relativistic effect…