Newsletter >> Topic - Green Card Information Boats Phentermine online Ladies handbag furniture Mobiles Loan Online Online notebook shop Necklace auto-moto Best Ringtones Chairs Intimate goods Free Ringtones Cigarettes Credits Dating Underwear Free Ringtones Autos Vicodin online Pills, Compare pills, Reviews pills Tunings Hydrocodone online Ambien online Sport Betting Fioricet online Free mp3 ringtones Rolex Replica Ornaments Cars Xanax online Bracelets Building materials Cialis online Soma online ya.by Ear rings Sportswear Trousers Cheap pharmacy shop Balans Get ringtones online FDA Approved Pharmacy Cheap drugs online shop Valium online Boots Tramadol online Download Ringtones Cases Fashions Top casino Cigarette Suits Phentermine No Prescription Top auto-moto Medical tests Evening dress Blog Search the Web Replica Rolex Rington mp3 music for mobile Adipex online Tables Chronometer

The interplay of disk wind and dynamical ejecta in the aftermath of neutron star - black hole mergers. (arXiv:1412.5588v1 [astro-ph.HE])

December 19th, 2014

Rodrigo Fernández, Eliot Quataert, Josiah Schwab, Daniel Kasen, Stephan Rosswog

We explore the evolution of the different ejecta components generated during
the merger of a neutron star (NS) and a black hole (BH). Our focus is the
interplay between material ejected dynamically during the merger, and the wind
launched on a viscous timescale by the remnant accretion disk. These components
are expected to contribute to an electromagnetic transient and to produce
r-process elements, each with a different signature when considered separately.
Here we introduce a two-step approach to investigate their combined evolution,
using two- and three-dimensional hydrodynamic simulations. Starting from the
output of a merger simulation, we identify each component in the initial
condition based on its phase space distribution, and evolve the accretion disk
in axisymmetry. The wind blown from this disk is injected into a
three-dimensional computational domain where the dynamical ejecta is evolved.
We find that the wind can suppresses fallback accretion on timescales longer
than ~100 ms. Due to self-similar viscous evolution, the disk accretion at late
times nevertheless approaches a power-law time dependence $\propto t^{-2.2}$.
This can power some late-time GRB engine activity, although the available
energy is significantly less than in traditional fallback models. Inclusion of
radioactive heating due to the r-process does not significantly affect the
fallback accretion rate or the disk wind. We do not find any significant
modification to the wind properties at large radius due to interaction with the
dynamical ejecta. This is a consequence of the different expansion velocities
of the two components.


http://arxiv.org/abs/1412.5588


Posted in All Recent GRB Papers | Comments Off

Short vs. Long Gamma-Ray Bursts: A Comprehensive Study of Energetics and Prompt Gamma-Ray Correlations. (arXiv:1412.5630v1 [astro-ph.HE])

December 19th, 2014


Posted in All Recent GRB Papers | Comments Off

The width of gamma-ray burst spectra. (arXiv:1412.5692v1 [astro-ph.HE])

December 19th, 2014


Posted in All Recent GRB Papers | Comments Off

On the role of fast magnetic reconnection in accreting black hole sources. (arXiv:1411.0883v2 [astro-ph.HE] UPDATED)

December 18th, 2014


Posted in All Recent GRB Papers | Comments Off

Synergy of short gamma ray burst and gravitational wave observations: Constraining the inclination angle of the binary and possible implications for off-axis gamma ray bursts. (arXiv:1403.6917v2 [astro-ph.HE] UPDATED)

December 16th, 2014


Posted in All Recent GRB Papers | Comments Off

The role of fast magnetic reconnection on the radio and gamma-ray emission from the nuclear regions of microquasars and low luminosity AGNs. (arXiv:1410.3454v2 [astro-ph.HE] UPDATED)

December 16th, 2014


Posted in All Recent GRB Papers | Comments Off

Selection effects in Gamma Ray Bursts correlations: consequences on the ratio between GRB and star formation rates. (arXiv:1412.3969v2 [astro-ph.HE] UPDATED)

December 16th, 2014


Posted in All Recent GRB Papers | Comments Off

Measuring the bulk Lorentz factors of gamma-ray bursts with Fermi. (arXiv:1412.3342v1 [astro-ph.HE])

December 11th, 2014


Posted in All Recent GRB Papers | Comments Off

GRB 140619B: a short GRB from a binary neutron stars merger leading to the black hole formation. (arXiv:1412.1018v2 [astro-ph.HE] UPDATED)

December 10th, 2014


Posted in All Recent GRB Papers | Comments Off

ASTRO-H White Paper - Chemical Evolution in High-z Universe. (arXiv:1412.1179v1 [astro-ph.HE])

December 4th, 2014


Posted in All Recent GRB Papers | Comments Off

« Previous Entries