INVESTIGADORES
ROMERO Gustavo Esteban
artículos
Título:
Cosmic reionization by primordial cosmic rays
Autor/es:
TUEROS, MATÍAS JORGE; DEL VALLE, MARÍA VICTORIA; ROMERO, GUSTAVO ESTEBAN
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP SCIENCES S A
Referencias:
Lugar: Paris; Año: 2014 vol. 570 p. 1 - 4
ISSN:
0004-6361
Resumen:
Context. After the so-called cosmic recombination, the expanding
universe entered into a period of darkness since most of the matter was
in a neutral state. About a billion years later, however, the
intergalactic space was once again ionized. The process, known as the
cosmic reionization, required the operation of mechanisms that are not
well understood. Among other ionizing sources, Population III stars,
mini-quasars, and X-ray emitting microquasars have been invoked.
Aims: We propose that primordial cosmic rays, accelerated at the
termination points of the jets of the first microquasars, may have
contributed to the reionization of the intergalactic space as well. Methods: We quantify the ionization power of cosmic rays (electrons
and protons) in the primordial intergalactic medium. This power is
calculated using extensive particle cascade simulations. Results:
We establish that, depending on the fraction of electrons to protons
accelerated in the microquasar jets, cosmic rays should have contributed
to the reionization of the primordial intergalactic medium as much as
X-rays from microquasar accretion disks. If the primordial magnetic
field was of the order of 10-17 G, as some models suggest,
cosmic rays had an important role in ionizing the neutral material far
beyond the birth places of the first stars.