1,135 research outputs found
Cooling Properties of Cloudy Bag Strange Stars
As the chiral symmetry is widely recognized as an important driver of the
strong interaction dynamics, current strange stars models based on MIT bag
models do not obey such symmetry. We investigate properties of bare strange
stars using the Cloudy Bag Model, in which a pion cloud coupled to the
quark-confining bag is introduced such that chiral symmetry is conserved. We
find that in this model the decay of pions is a very efficient cooling way. In
fact it can carry out most the thermal energy in a few milliseconds and
directly convert them into 100MeV photons via pion decay. This may be a very
efficient -ray burst mechanism. Furthermore, the cooling behavior may
provide a possible way to distinguish a compact object between a neutron star,
MIT strange star and Cloudy Bag strange star in observations.Comment: 23 pages, 14 figures, accepted by Astroparticle Physics, abstract
appeared here has been shortene
The detection of Gravitational Waves
This chapter is concerned with the question: how do gravitational waves (GWs)
interact with their detectors? It is intended to be a theory review of the
fundamental concepts involved in interferometric and acoustic (Weber bar) GW
antennas. In particular, the type of signal the GW deposits in the detector in
each case will be assessed, as well as its intensity and deconvolution. Brief
reference will also be made to detector sensitivity characterisation, including
very summary data on current state of the art GW detectors.Comment: 33 pages, 12 figures, LaTeX2e, Springer style files --included. For
Proceedings of the ERE-2001 Conference (Madrid, September 2001
Improved full one-loop corrections to A^0 -> \sf_1 \sf_2 and \sf_2 -> \sf_1 A^0
We calculate the full electroweak one-loop corrections to the decay of the
CP-odd Higgs boson A^0 into scalar fermions in the minimal supersymmetric
extension of the Standard Model. For this purpose many parameters of the MSSM
have to be properly renormalized in the on-shell renormalization scheme. We
have also included the SUSY-QCD corrections. For the decay into bottom squarks
and tau sleptons, especially for large \tan\b, the corrections can be very
large making the perturbation expansion unreliable. We solve this problem by an
appropriate definition of the tree-level coupling in terms of running fermion
masses and running trilinear couplings A_f. We also discuss the decay of heavy
scalar fermions into light scalar fermions and A^0. We find that the
corrections can be sizeable and therefore cannot be neglected.Comment: 42 pages, 20 figures (23 eps-files
WITHDRAWN: Herbalists, traditional healers and pharmacists: a view of the tuberculosis in Ghana
The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/<10.1590/0102-695X2014241405>. The duplicate article has therefore been withdrawn.The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy
The T2K ND280 Off-Axis Pi-Zero Detector
The Pi-Zero detector (P{\O}D) is one of the subdetectors that makes up the
off-axis near detector for the Tokai-to-Kamioka (T2K) long baseline neutrino
experiment. The primary goal for the P{\O}D is to measure the relevant cross
sections for neutrino interactions that generate pi-zero's, especially the
cross section for neutral current pi-zero interactions, which are one of the
dominant sources of background to the electron neutrino appearance signal in
T2K. The P{\O}D is composed of layers of plastic scintillator alternating with
water bags and brass sheets or lead sheets and is one of the first detectors to
use Multi-Pixel Photon Counters (MPPCs) on a large scale.Comment: 17 pages, submitted to NIM
Optical Properties of III-Mn-V Ferromagnetic Semiconductors
We review the first decade of extensive optical studies of ferromagnetic,
III-Mn-V diluted magnetic semiconductors. Mn introduces holes and local moments
to the III-V host, which can result in carrier mediated ferromagnetism in these
disordered semiconductors. Spectroscopic experiments provide direct access to
the strength and nature of the exchange between holes and local moments; the
degree of itineracy of the carriers; and the evolution of the states at the
Fermi energy with doping. Taken together, diversity of optical methods reveal
that Mn is an unconventional dopant, in that the metal to insulator transition
is governed by the strength of the hybridization between Mn and its p-nictogen
neighbor. The interplay between the optical, electronic and magnetic properties
of III-Mn-V magnetic semiconductors is of fundamental interest and may enable
future spin-optoelectronic devices.Comment: Topical Revie
Phenomenology of the Lense-Thirring effect in the Solar System
Recent years have seen increasing efforts to directly measure some aspects of
the general relativistic gravitomagnetic interaction in several astronomical
scenarios in the solar system. After briefly overviewing the concept of
gravitomagnetism from a theoretical point of view, we review the performed or
proposed attempts to detect the Lense-Thirring effect affecting the orbital
motions of natural and artificial bodies in the gravitational fields of the
Sun, Earth, Mars and Jupiter. In particular, we will focus on the evaluation of
the impact of several sources of systematic uncertainties of dynamical origin
to realistically elucidate the present and future perspectives in directly
measuring such an elusive relativistic effect.Comment: LaTex, 51 pages, 14 figures, 22 tables. Invited review, to appear in
Astrophysics and Space Science (ApSS). Some uncited references in the text
now correctly quoted. One reference added. A footnote adde
Measurement of and charged current inclusive cross sections and their ratio with the T2K off-axis near detector
We report a measurement of cross section and the first measurements of the cross section
and their ratio
at (anti-)neutrino energies below 1.5
GeV. We determine the single momentum bin cross section measurements, averaged
over the T2K -flux, for the detector target material (mainly
Carbon, Oxygen, Hydrogen and Copper) with phase space restricted laboratory
frame kinematics of 500 MeV/c. The
results are and $\sigma(\nu)=\left( 2.41\
\pm0.022{\rm{(stat.)}}\pm0.231{\rm (syst.)}\ \right)\times10^{-39}^{2}R\left(\frac{\sigma(\bar{\nu})}{\sigma(\nu)}\right)=
0.373\pm0.012{\rm (stat.)}\pm0.015{\rm (syst.)}$.Comment: 18 pages, 8 figure
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