5,012 research outputs found
Overview of Charm Physics at RHIC
Heavy-quark production provides a sensitive probe of the gluon structure of
nucleons and its modication in nuclei. It is also a key probe of the hot-dense
matter created in heavy-ion collisions. We will discuss the physics issues
involved, as seen in quarkonia and open heavy-quark production, starting with
those observed in proton-proton collisions. Then cold nuclear matter effects on
heavy-quark production including shadowing, gluon saturation, energy loss and
absorption will be reviewed in the context of recent proton-nucleus and
deuteron-nucleus measurements. Next we survey the most recent measurements of
open-charm and J/Psi's in heavy-ion collisions at RHIC and their
interpretation. We discuss the high-pT suppression and flow of open charm in
terms of energy loss and thermalization and, for J/Psi, contrast explanations
in terms of screening in a deconfined medium vs. recombination models.Comment: 6 pages, 12 figures, proceedings for Quark Confinement and Hadron
Spectrum VI
Optical Observations of the Binary Millisecond Pulsars J2145-0750 and J0034-0534
We report on optical observations of the low-mass binary millisecond pulsar
systems J0034-0534 and J2145-0750. A faint (I=23.5) object was found to be
coincident with the timing position of PSR J2145-0750. While a galaxy or
distant main-sequence star cannot be ruled out, its magnitude is consistent
with an ancient white dwarf, as expected from evolutionary models. For PSR
J0034-0534 no objects were detected to a limiting magnitude of R=25.0,
suggesting that the white dwarf in this system is cold. Using white dwarf
cooling models, the limit on the magnitude of the PSR J0034-0534 companion
suggests that at birth the pulsar in this system may have rotated with a period
as short as 0.6 ms. These observations provide further evidence that the
magnetic fields of millisecond pulsars do not decay on time scales shorter than
1 Gyr.Comment: 6 pages, uuencoded, gz -9 compressed postscript, accepted by ApJ
Intravenous conscious sedation in patients under 16 years of age. Fact or fiction?
Recently published guidelines on the use of conscious sedation in dentistry have published varying recommendations on the lower age limit for the use of intravenous conscious sedation. There are a large number of dentists currently providing dental treatment for paediatric patients under intravenous conscious sedation. The 18 cases reported here (age range 11-15 years), were successfully managed with intravenous conscious sedation. The experience in this paper is not sufficient evidence to recommend the wholesale use of intravenous conscious sedation in patients who are under 16 years. The fact that a range of operators can use these techniques on paediatric patients would suggest that further study should be carried out in this population. The guidance should be modified to say there is insufficient evidence to support the use of intravenous conscious sedation in children, rather than arbitrarily selecting a cut off point at age 16 years
A Sunyaev-Zel'dovich Effect Survey for High Redshift Clusters
Interferometric observations of the Sunyaev-Zel'dovich Effect (SZE) toward
clusters of galaxies provide sensitive cosmological probes. We present results
from 1 cm observations (at BIMA and OVRO) of a large, intermediate redshift
cluster sample. In addition, we describe a proposed, higher sensitivity array
which will enable us to survey large portions of the sky. Simulated
observations indicate that we will be able to survey one square degree of sky
per month to sufficient depth that we will detect all galaxy clusters more
massive than 2x10^{14} h^{-1}_{50}M_\odot, regardless of their redshift. We
describe the cluster yield and resulting cosmological constraints from such a
survey.Comment: 7 pages, 6 figures, latex, contribution to VLT Opening Symposiu
Latest Results on the Hot-Dense Partonic Matter at RHIC
At the Relativistic Heavy Ion Collider (RHIC) collisions of heavy ions at
nucleon-nucleon energies of 200 GeV appear to have created a new form of matter
thought to be a deconfined state of the partons that ordinarily are bound in
nucleons.We discuss the evidence that a thermalized partonic medium, usually
called a Quark Gluon Plasma (QGP), has been produced. Then we discuss the
effect of this high-density medium on the production of jets and their pair
correlations. Next we look at direct photons as a clean electro-magnetic probe
to constrain the initial hard scatterings. Finally we review the developing
picture for the effect of this medium on the production of open heavy quarks
and on the screening by the QGP of heavy-quark bound states.Comment: 6 pages, 14 figures, proceedings for QNP06 (5-10 June, 2006) invited
tal
Next generation sequencing analysis reveals a relationship between rDNA unit diversity and locus number in Nicotiana diploids
© 2012 Matyášek et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly cited
Chromosomal diversification and karyotype evolution of diploids in the cytologically diverse genus Prospero (Hyacinthaceae)
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited
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