38,927 research outputs found
Direct CP Violation in Charmless B Decays at LHCb
Using data collected by LHCb experiment in 2011 we report the measurements of
charge asymmetries in charmless decays of B mesons in two or three charged
kaons or pions. We find positive charge asymmetries in the channels
Bs->K-pi+(3.3 sigmas), B+->K+pi+pi- (2.8 sigmas), and B+->pi+pi+pi- (4.2
sigmas) and negative in B0->K+pi-(6 sigmas),B+->K+K+K- (3.7 sigma), B+->K+K-pi+
(3.0 sigma).Comment: Proceedings of CKM 2012, the 7th International Workshop on the CKM
Unitarity Triangle, University of Cincinnati, USA, 28 September - 2 October
201
Sub-arcsecond Morphology of Planetary Nebulae
Planetary nebulae (PNe) can be roughly categorized into several broad
morphological classes. The high quality images of PNe acquired in recent years,
however, have revealed a wealth of fine structures that preclude simplistic
models for their formation. Here we present narrow-band, sub-arcsecond images
of a sample of relatively large PNe that illustrate the complexity and variety
of small-scale structures. This is especially true for bipolar PNe, for which
the images reveal multi-polar ejections and, in some cases, suggest turbulent
gas motions. Our images also reveal the presence or signs of jet-like outflows
in several objects in which this kind of component has not been previously
reported.Comment: 7 pages, 7 figures, Accepted for publication in PAS
The effect of low mass substructures on the Cusp lensing relation
It has been argued that the flux anomalies detected in gravitationally lensed
QSOs are evidence for substructures in the foreground lensing haloes. In this
paper we investigate this issue in greater detail focusing on the Cusp relation
which corresponds to images of a source located to the cusp of the inner
caustic curve. We use numerical simulations combined with a Monte Carlo
approach to study the effects of the expected power law distribution of
substructures within LCDM haloes on the multiple images.
Generally, the high number of anomalous flux ratios in the cusp
configurations is unlikely explained by 'simple' perturbers (subhaloes) inside
the lensing galaxy, either modeled by point masses or extended NFW subhaloes.
We considered in our analysis a mass range of 10^5-10^7 Msun for the subhaloes.
We also demonstrate that including the effects of the surrounding mass
distribution, such as other galaxies close to the primary lens, does not change
the results. We conclude that triple images of lensed QSOs do not show any
direct evidence for dark dwarf galaxies such as cold dark matter substructure.Comment: 10 pages, 19 figures, Effects of different subhalos concentrations
discussed, analysis improved, accepted by MNRA
Seed Magnetic Fields Generated by Primordial Supernova Explosions
The origin of the magnetic field in galaxies is an open question in
astrophysics. Several mechanisms have been proposed related, in general, with
the generation of small seed fields amplified by a dynamo mechanism. In
general, these mechanisms have difficulty in satisfying both the requirements
of a sufficiently high strength for the magnetic field and the necessary large
coherent scales. We show that the formation of dense and turbulent shells of
matter, in the multiple explosion scenario of Miranda and Opher (1996, 1997)
for the formation of the large-scale structures of the Universe, can naturally
act as a seed for the generation of a magnetic field. During the collapse and
explosion of Population III objects, a temperature gradient not parallel to a
density gradient can naturally be established, producing a seed magnetic field
through the Biermann battery mechanism. We show that seed magnetic fields can be produced in this multiple explosion scenario on
scales of the order of clusters of galaxies (with coherence length ) and up to on scales of galaxies ().Comment: Accepted for publication in MNRAS, 5 pages (MN plain TeX macros v1.6
file). Also available at http://www.iagusp.usp.br/~oswaldo (click "OPTIONS"
and then "ARTICLES"
The needs of people with dementia living at home from user, caregiver and professional perspectives: a cross-sectional survey
Few reports have been published about differences in perspectives on perceived needs among community-residing people with dementia, their family caregivers, and professionals. The aim of this study was to compare these perspectives
Iraq and Afghanistan veteransâ experiences living with their parents after separation from the military
When military service members separate from the military, many return to their families of origin, living with their parents for a period of several weeks to years. While research with veterans and their spouses has documented the particular strain of this reintegration period on veterans and their partners, little research to date has examined veteransâ experiences living with their parents. The present study sought to fill this research gap by investigating veteransâ experiences living with their parents using qualitative, in-depth interviews with Iraq and Afghanistan veterans in California. Overall, veterans appreciated the instrumental and emotional support their parents provided when they separated. However, in some cases, living with parents also produced conflict and strain. In situations where adult veteran children had difficulty with the transition to civilian life or returned with mental health problems, parents were often the first to identify these problems and to support their children in accessing appropriate care. We analyze these findings in light of family systems theory, identifying ways in which adult veteran children continue a process of differentiation while living with their parents and maintaining emotional connectedness. We suggest ways that clinicians can better support veterans and their parents through the reintegration period and recommend that programming for military families explicitly include parents of service members in addition to conjugal families
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