A. V. Penacchioni, R. Ruffini, L. Izzo, M. Muccino, C. L. Bianco, L. Caito, B. Patricelli, L. Amati
[Shortened] Context: [...] we point out a striking similarity between GRB
101023 and GRB 090618. We explore the possibility that these sources are
members of a new GRB family related to a single core-collapse. We use this
understanding of the source in order to infer the unobserved redshift of GRB
101023. [...]. Aims: In precise analogy with GRB 090618 we aim to analyze the
89s of emission of GRB 101023 to see if we are in presence of two different
episodes: the first one presenting a characteristic Black-body temperature
evolution, evolving in time with a broken power-law, and the second one
consistent with a canonical GRB. [...] Results: We confirm that the first
episode can be well fit by a Black body plus a power-law model. The temperature
changes with time following a broken power law, and the photon index of the
power-law component presents a soft to hard evolution. We estimate the radius
of this source, increasing with time with a velocity of 1.5x10^4 km/s. The
second episode appears to be a canonical GRB. By using the Amati relation and
the Atteia relation, we determine the cosmological redshift, z ~ 0.9 +- 0.084
(stat.) +- 0.2 (sys.). [...]. Particularly striking is the scaling law of the
soft X-ray component of the afterglow. Conclusions: We identify GRB 090618 and
GRB 101023 with a new family of GRBs presenting a double astrophysical
component. A first one, related to the proto-black hole, prior to the process
of gravitational collapse (episode 1) and a second one which is the canonical
GRB (episode 2) emitted during the formation of the black-hole. [...] This
analysis indicates progress towards developing a GRB distance indicator based
on the understanding of the P-GRB and the prompt radiation as well as the soft
X-Ray behavior of the late afterglow.
View original:
http://arxiv.org/abs/1112.2970
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