Bissaldi 2007 检验GRB和Ib/c型超新星的成协

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astro-ph/0702652 [abs, ps, pdf, other] :

Title: The connection between Gamma-ray bursts and Supernovae Ib/c
Authors: Elisabetta Bissaldi (1), Francesco Calura (2), Francesca Matteucci (2,3), Francesco Longo (1,4), Guido Barbiellini (1,4) (1: Dip. di Fisica, Universita' di Trieste; 2: INAF-Osservatorio Astronomico di Trieste; 3: Dip. di Astronomia, Universita' di Trieste; 4: INFN, sezione di Trieste)
Comments: A&A, in press, 15 pages, 11 figures

It has been established that Gamma-Ray Bursts (GRBs) are connected to Supernovae (SNe) explosions of Type Ib/c. We intend to test whether the hypothesis of Type Ib/c SNe from different massive progenitors can reproduce the local GRB rate as well as the GRB rate as a function of redshift. We aim to predict the GRB rate at very high redshift under different assumptions about galaxy formation and star formation histories in galaxies. We assume different star formation histories in galaxies of different morphological type: ellipticals, spirals and irregulars. We explore different hypotheses concerning the progenitors of Type Ib/c SNe. We find an excellent agreement between the observed GRB local rate and the predicted Type Ib/c SN rate in irregular galaxies, when a range for single Wolf-Rayet stars of 40-100 M_sun is adopted. We also predict the cosmic Type Ib/c SN rate by taking into account all the galaxy types in an unitary volume of the Universe and we compare it with the observed cosmic GRB rate as a function of redshift. By assuming the formation of spheroids at high redshift, we predict a cosmic Type Ib/c SN rate, which is always higher than the GRB rate, suggesting that only a small fraction (0.1-1 %) of Type Ib/c SNe become GRBs. In particular, we find a ratio between the cosmic GRB rate and the cosmic Type Ib/c rate in the range 0.001-0.01, in agreement with previous estimates. Finally, due to the high star formation in spheroids at high redshift, which is our preferred scenario for galaxy formation, we predict more GRBs at high redshift than in the hierarchical scenario for galaxy formation, a prediction which awaits to be proven by future observations.