23,503 research outputs found
New magic number for neutron rich Sn isotopes
The variation of E(2+_1) of (134-140)Sn calculated with empirical SMPN
interaction has striking similarity with that of experimental E(2+_1) of
even-even (18-22)O and (42-48)Ca, showing clearly that N=84-88 spectra exhibit
the effect of gradual filling up of \nu(2f_{7/2}) orbital which finally
culminates in a new shell closure at N=90. Realistic two-body interaction CWG
does not show this feature. Spin-tensor decomposition of SMPN and CWG
interactions and variation of their components with valence neutron number
reveals that the origin of the shell closure at 140Sn lies in the three body
effects. Calculations with CWG3, which is obtained by including a simple
three-body monopole term in the CWG interaction, predict decreasing E(2+_1) for
(134-138)Sn and a shell closure at 140Sn.Comment: 4 pages, 5 figure
GROWTH CONSEQUENCES OF FOREIGN DIRECT INVESTMENT: SOME RESULTS FOR TURKEY
Turkey has become the dominant recipient of FDI inflows in the Western Asian region. We explore if such inflows have promoted growth as expected. Our analysis of the FDI/growth nexus focuses both on the long-and short-run relations and allows for the possibility that growth also responds to other factors. The results support the theoretical priors and support the existence of a robust long-run relationship linking real economic growth with FDI inflows, economic openness and human capital. Among the three growth ingredients, only human capital accumulation (good education) appears capable of stimulating economic growth in the short-run as well. The results further imply that programs to attract larger FDI inflows to Turkey should persist for some time before they can produce noticeable economic benefits.FDI Inflows, Economic Growth, Human Capital, Turkey
A "Baedecker" for the Dark Matter Annihilation Signal
We provide a ``Baedecker'' or travel guide to the directions on the sky where
the dark matter annihilation signal may be expected. We calculate the flux of
high energy gamma-rays from annihilation of neutralino dark matter in the
centre of the Milky Way and the three nearest dwarf spheroidals (Sagittarius,
Draco and Canis Major), using realistic models of the dark matter distribution.
Other investigators have used cusped dark halo profiles (such as the
Navarro-Frenk-White) to claim a significant signal. This ignores the
substantial astrophysical evidence that the Milky Way is not dark-matter
dominated in the inner regions. We show that the annihilation signal from the
Galactic Centre falls by two orders of magnitude on substituting a cored dark
matter density profile for a cusped one. The present and future generation of
high energy gamma-ray detectors, whether atmospheric Cerenkov telescopes or
space missions like GLAST, lack the sensitivity to detect any of the
monochromatic gamma-ray annihilation lines. The continuum gamma-ray signal
above 1 GeV and above 50 GeV may however be detectable either from the dwarf
spheroidals or from the Milky Way itself. If the density profiles of the dwarf
spheroidals are cusped, then the best prospects are for detecting Sagittarius
and Canis Major. However, if the dwarf spheroidals have milder, cored profiles,
then the annihilation signal is not detectable. For GLAST, an attractive
strategy is to exploit the wide field of view and observe the Milky Way at
medium latitudes, as suggested by Stoehr et al. This is reasonably robust
against changes in the density profile.Comment: 13 pages, 3 figures, version in press at The Physical Review
On the Thermodynamic Geometry of Hot QCD
We study the nature of the covariant thermodynamic geometry arising from the
free energy of hot QCD. We systematically analyze the underlying equilibrium
thermodynamic configurations of the free energy of 2- and 3-flavor hot QCD with
or without including thermal fluctuations in the neighborhood of the QCD
transition temperature. We show that there exists a well-defined thermodynamic
geometric notion for QCD thermodynamics. The geometry thus obtained has no
singularity as an intrinsic Riemannian manifold. We further show that there is
a close connection of this geometric approach with the existing studies of
correlations and quark number susceptibilities in hot QCD.Comment: 15 pages, 12 figures, Keywords: Thermodynamic Geometry, Hot QCD,
Quasi-particles, PACS: 12.38.-t; 05.70.Fh; 02.40.Ky; 12.40.E
Renormalization group and isochronous oscillations
We show how the condition of isochronicity can be studied for two dimensional
systems in the renormalization group (RG) context. We find a necessary
condition for the isochronicity of the Cherkas and another class of cubic
systems. Our conditions are satisfied by all the cases studied recently by
Bardet et al \cite{bard} and Ghose Choudhury and Guh
Double Beta Decay, Lepton Flavour Violation and Collider Signatures of Left-Right Symmetric Models with Spontaneous D Parity Breaking
We propose a class of left-right symmetric models (LRSMs) with spontaneous D
parity breaking, where SU(2)_R breaks at the TeV scale while discrete
left-right symmetry breaks around 10^9 GeV. By embedding this framework in a
non-supersymmetric SO(10) Grand Unified Theory (GUT) with Pati-Salam symmetry
as the highest intermediate breaking step, we obtain g_R / g_L ~ 0.6 between
the right- and left-handed gauge couplings at the TeV scale. This leads to a
suppression of beyond the Standard Model phenomena induced by the right-handed
gauge coupling. Here we focus specifically on the consequences for neutrinoless
double beta decay, low energy lepton flavour violation and LHC signatures due
to the suppressed right handed currents. Interestingly, the reduced g_R allows
us to interpret an excess of events observed recently in the range of 1.9 TeV
to 2.4 TeV by the CMS group at the LHC as the signature of a right handed gauge
boson in LRSMs with spontaneous D parity breaking. Moreover, the reduced
right-handed gauge coupling also strongly suppresses the non-standard
contribution of heavy states to the neutrinoless double beta decay rate as well
as the amplitude of low energy lepton flavour violating processes. In a
dominant type-II Seesaw mechanism of neutrino mass generation, we find that
both sets of observables provide stringent and complimentary bounds which make
it challenging to observe the scenario at the LHC.Comment: 20 pages, 11 figure
Adolescents' and parents' views of Child and Adolescent Mental Health Services (CAMHS) in Ireland
Aim: To explore adolescents’ and parents’ experiences of CAMHS in relation to accessibility, approachability, and appropriateness. Methods: Using a descriptive qualitative design, a combination of focus group and single interviews were conducted with adolescents (n=15) and parents (n=32) from three mental health clinics. Data were transcribed verbatim and analysed using thematic analysis. Results: Accessing mental health services was a challenging experience due to knowledge deficit, lack of information and limited availability of specialist services. Participants desired more information, involvement in decision-making, single and shared consultations, flexible scheduling of appointments, continuity with clinicians, school support and parent support groups. Participants seem to be generally satisfied, however adolescents felt less involved in decision making than they would have liked. Frequent staff changes was problematic as it disrupted continuity of care and hindered the formation of a trusting relationship. Implications for practice: Parents and adolescents expressed similar views of the positive and negative aspects of mental health services. Their need for more information-sharing and involvement in decision-making underline the importance of collaborative practice. Clinician continuity contributed to trusting therapeutic relationships and was valued. These are key principles that with attention, could lead to quality service provision for adolescents and families
Signal of Right-Handed Charged Gauge Bosons at the LHC?
We point out that the recent excess observed in searches for a right-handed
gauge boson W_R at CMS can be explained in a left-right symmetric model with D
parity violation. In a class of SO(10) models, in which D parity is broken at a
high scale, the left-right gauge symmetry breaking scale is naturally small,
and at a few TeV the gauge coupling constants satisfy g_R ~ 0.6 g_L. Such
models therefore predict a right-handed charged gauge boson W_R in the TeV
range with a suppressed gauge coupling as compared to the usually assumed
manifest left-right symmetry case g_R = g_L. The recent CMS data show excess
events which are consistent with the cross section predicted in the D parity
breaking model for 1.9 TeV < M_{W_R} < 2.4 TeV. If the excess is confirmed, it
would in general be a direct signal of new physics beyond the Standard Model at
the LHC. A TeV scale W_R would for example not only rule out SU(5) grand
unified theory models. It would also imply B-L violation at the TeV scale,
which would be the first evidence for baryon or lepton number violation in
nature and it has strong implications on the generation of neutrino masses and
the baryon asymmetry in the Universe.Comment: 4 pages, 2 figures, matches published versio
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