2,271 research outputs found
Neutrinos from Gamma Ray Bursts in the IceCube and ARA Era
In this review I discuss the ultra-high energy neutrinos (UHEN) originated
from Cosmic-Rays propogation (GZK neutrinos) and from Gamma Ray Bursts (GRBs),
and discuss their detectability in kilometers scale detectors like ARA and
IceCube.
While GZK neutrinos are expected from cosmic ray interactions on the CMB, the
GRB neutrinos depend on the physics inside the sources. GRBs are predicted to
emit UHEN in the prompt and in the later 'after-glow' phase.
I discuss the constraints on the hadronic component of GRBs derived from the
search of four years of IceCube data for a prompt neutrino fux from gamma-ray
bursts (GRBs) and more in general I present the results of the search for
high-energy neutrinos interacting within the IceCube detector between 2010 and
2013.Comment: Accepted for publication in Journal of High Energy Astrophysics.
arXiv admin note: text overlap with arXiv:1407.015
The rate and luminosity function of Short GRBs
We compare the luminosity function and rate inferred from the BATSE short
hard bursts (SHBs) peak flux distribution with the redshift and luminosity
distributions of SHBs observed by Swift/HETE II. The Swift/HETE II SHB sample
is incompatible with SHB population that follows the star formation rate.
However, it is compatible with a distribution of delay times after the SFR.
This would be the case if SHBs are associated with binary neutron star mergers.
The implied SHB rates that we find range from \sim 8 to \sim
30h_{70}^3Gpc^{-3}yr^{-1}. This rate is a much higher than what was previously
estimated and, when beaming is taken into account, it is comparable to the rate
of neutron star mergers estimated from statistics of binary pulsars. If GRBs
are produced in mergers the implied rate practically guarantees detection by
LIGO II and possibly even by LIGO I, if we are lucky. Our analysis, which is
based on observed short hard burst is limited to bursts with luminosities above
10^{49}erg/sec. Weaker bursts may exist but if so they are hardly detected by
BATSE or Swift and hence their rate is very weakly constrained by current
observations. Thus the rate of mergers that lead to a detection of a
gravitational radiation signal might be even higher.Comment: Proceedings of the conference on "Gamma Ray Bursts in the Swift Era",
November 29,-December 2, Washington, D
Solid image extraction from LIDAR point clouds
In laser scanner architectural surveying it is necessary to extract orthogonal projections from the tridimensional model, plans, elevations and cross sections. The paper presents the workflow of architectural drawings production from laser scans, focusing on the orthogonal projection of the point cloud on solid images, in order to avoid the time consuming surface modeling, when it is not strictly necessary. The proposed procedures have been implemented in fortran90 and included in the VELOCE software package, then tested and applied to the case study of the San Pietro church in Porto Venere (SP), integrating the architectural surveying with an existing bathymetric and coastal surveyin
Piensa globalmente, actúa localmente: mapeo de la cultura libre en un sistema mediático hÃbrido
From the nineties, the Internet has been providing new political hybrid action forms. At the
same time, some communities make a disruptive use of technologies aiming to subvert
network power relationships at the current capitalized and centralized cyberspace.
Addressing a collaborative mapping, we identified 290 free culture communities in
Spain. Their characteristics suggest the relevance of offline spaces and local areas to
deliberate, propose and perform political participation towards a neutral, centralised
and free Internet.Desde los años noventa, el ciberespacio ha propuesto formas acción polÃtica hÃbrida.
Asimismo, algunos colectivos realizan un uso disruptivo de las tecnologÃas para subvertir las
relaciones de poder en la Red. Mediante un mapeo colaborativo, identificamos 290 grupos
relacionados con la cultura libre en España. Sus caracterÃsticas sugieren la relevancia de los
espacios offline y de los territorios locales para deliberar y activarse polÃticamente a favor
de un Internet libre
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