The cepheid-like relationship between variability and luminosity explainedwithin the "cannonball model" of gamma-ray bursts

Authors
Citation
R. Plaga, The cepheid-like relationship between variability and luminosity explainedwithin the "cannonball model" of gamma-ray bursts, ASTRON ASTR, 370(2), 2001, pp. 351-357
Citations number
39
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
0004-6361 → ACNP
Volume
370
Issue
2
Year of publication
2001
Pages
351 - 357
Database
ISI
SICI code
0004-6361(200105)370:2<351:TCRBVA>2.0.ZU;2-I
Abstract
I show how an empirical variability - luminosity relationship for prompt ga mma-ray bursts, first proposed by Fenimore and Ramirez-Ruiz. can be underst ood as a special-relativistic beaming effect in the "cannonball model" of D ar and De Rujula. In this scenario the variability is a measure of the dire ction of propagation and the Lorentz factor of the cannonball on which in t urn the apparent luminosity of the prompt GRB depends sensitively. The obse rved absence of cosmological time dilation in the "aligned peak test" - whe n using redshifts derived with this relation - is also explained. The most direct evidence in favour of the cannonball model presented here is its cor rect description for the observed relation between narrow-spike width and a mplitude within a given GRB. There seems to be an indication for cosmologic al time dilation in the total duration of GRBs, as expected in the cannonba ll model. Quantitative predictions for the luminosity function of GRBs and the "spectral-lag luminosity relation" are given.