35,390 research outputs found
Torsion-Adding and Asymptotic Winding Number for Periodic Window Sequences
In parameter space of nonlinear dynamical systems, windows of periodic states
are aligned following routes of period-adding configuring periodic window
sequences. In state space of driven nonlinear oscillators, we determine the
torsion associated with the periodic states and identify regions of uniform
torsion in the window sequences. Moreover, we find that the measured of torsion
differs by a constant between successive windows in periodic window sequences.
We call this phenomenon as torsion-adding. Finally, combining the torsion and
the period adding rules, we deduce a general rule to obtain the asymptotic
winding number in the accumulation limit of such periodic window sequences
Detectability of the First Cosmic Explosions
We present a fully self-consistent simulation of a synthetic survey of the
furthermost cosmic explosions. The appearance of the first generation of stars
(Population III) in the Universe represents a critical point during cosmic
evolution, signaling the end of the dark ages, a period of absence of light
sources. Despite their importance, there is no confirmed detection of
Population III stars so far. A fraction of these primordial stars are expected
to die as pair-instability supernovae (PISNe), and should be bright enough to
be observed up to a few hundred million years after the big bang. While the
quest for Population III stars continues, detailed theoretical models and
computer simulations serve as a testbed for their observability. With the
upcoming near-infrared missions, estimates of the feasibility of detecting
PISNe are not only timely but imperative. To address this problem, we combine
state-of-the-art cosmological and radiative simulations into a complete and
self-consistent framework, which includes detailed features of the
observational process. We show that a dedicated observational strategy using
per cent of total allocation time of the James Webb Space
Telescope mission can provide us up to detectable PISNe per year.Comment: 9 pages, 8 figures. Minor corrections added to match published
versio
Inclusive Breakup Theory of Three-Body Halos
We present a recently developed theory for the inclusive breakup of
three-fragment projectiles within a four-body spectator model
\cite{CarPLB2017}, for the treatment of the elastic and inclusive non-elastic
break up reactions involving weakly bound three-cluster nuclei in
/ collisions. The four-body theory is an extension of the
three-body approaches developed in the 80's by Ichimura, Autern and Vincent
(IAV) \cite{IAV1985}, Udagawa and Tamura (UT) \cite{UT1981} and Hussein and
McVoy (HM) \cite{HM1985}. We expect that experimentalists shall be encouraged
to search for more information about the system in the elastic
breakup cross section and that also further developments and extensions of the
surrogate method will be pursued, based on the inclusive non-elastic breakup
part of the spectrum.Comment: 8 pages, 3 figures, Contribution to the Proceedings of Fusion17:
"International Conference on Heavy-Ion Collisions at Near-Barrier Energies",
20-24 February 2017 Hobart, Tasmania, Australi
Reducing the parameter space for Unparticle-inspired models using white dwarf masses
Based on astrophysical constraints derived from Chandrasekhar's mass limit
for white-dwarfs, we study the effects of the model on the parameters of
unparticle-inspired gravity, on scales and .Comment: 4 pp., 4 Fig., to appear in PR
de Broglie-Proca and Bopp-Podolsky massive photon gases in cosmology
We investigate the influence of massive photons on the evolution of the
expanding universe. Two particular models for generalized electrodynamics are
considered, namely de Broglie-Proca and Bopp-Podolsky electrodynamics. We
obtain the equation of state (EOS) for each case using
dispersion relations derived from both theories. The EOS are inputted into the
Friedmann equations of a homogeneous and isotropic space-time to determine the
cosmic scale factor . It is shown that the photon non-null mass does not
significantly alter the result valid for a massless photon
gas; this is true either in de Broglie-Proca's case (where the photon mass
is extremely small) or in Bopp-Podolsky theory (for which is extremely
large).Comment: 8 pages, 2 figures; v2 matches the published versio
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