We employ a sample of 362 flat-spectrum radio quasars （FSRQs） to calculate their integrated luminosities by integrating the spectral energy distribution （SED） constructed with multi-band （radio, IR, optical, UV a...We employ a sample of 362 flat-spectrum radio quasars （FSRQs） to calculate their integrated luminosities by integrating the spectral energy distribution （SED） constructed with multi-band （radio, IR, optical, UV and X-ray） data. We compare these luminosities with those estimated from monochromatic luminosities by multi- plying them by the conventional bolometric correction factors. Our analysis shows that the integrated luminosities calculated from the SED are much larger than the bolometric luminosities estimated from monochromatic luminosities. Their departing behavior tightly correlates with radio luminosities. The relations between integrated and monochromatic luminosities are explored, which are regarded as empirical rela- tions that might be more suitable to be applied to estimate integrated luminosities of FSRQs from their monochromatic luminosities.展开更多
We investigate the forming of gamma-ray burst pulses with a simple onedimensional relativistic shock model. The mechanism is that a ＂central engine＂ drives forward the nearby plasma inside the fireball to generate a...We investigate the forming of gamma-ray burst pulses with a simple onedimensional relativistic shock model. The mechanism is that a ＂central engine＂ drives forward the nearby plasma inside the fireball to generate a series of pressure waves. We give a relativistic geometric recurrence formula that connects the time when the pressure waves are produced and the time when the corresponding shocks occurred. This relation enables us to relate the pulse magnitude with the observation time. Our analysis shows that the evolution of the pressure waves leads to a fast rise and an exponential decay pulses. In determining the width of the pulses, the acceleration time is more important than that of the deceleration.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No. 10847003)
文摘We employ a sample of 362 flat-spectrum radio quasars （FSRQs） to calculate their integrated luminosities by integrating the spectral energy distribution （SED） constructed with multi-band （radio, IR, optical, UV and X-ray） data. We compare these luminosities with those estimated from monochromatic luminosities by multi- plying them by the conventional bolometric correction factors. Our analysis shows that the integrated luminosities calculated from the SED are much larger than the bolometric luminosities estimated from monochromatic luminosities. Their departing behavior tightly correlates with radio luminosities. The relations between integrated and monochromatic luminosities are explored, which are regarded as empirical rela- tions that might be more suitable to be applied to estimate integrated luminosities of FSRQs from their monochromatic luminosities.
基金Supported by the National Natural Science Foundation of China.
文摘We investigate the forming of gamma-ray burst pulses with a simple onedimensional relativistic shock model. The mechanism is that a ＂central engine＂ drives forward the nearby plasma inside the fireball to generate a series of pressure waves. We give a relativistic geometric recurrence formula that connects the time when the pressure waves are produced and the time when the corresponding shocks occurred. This relation enables us to relate the pulse magnitude with the observation time. Our analysis shows that the evolution of the pressure waves leads to a fast rise and an exponential decay pulses. In determining the width of the pulses, the acceleration time is more important than that of the deceleration.
