2,356 research outputs found
Consistent Skyrme parametrizations constrained by GW170817
The high-density behavior of the stellar matter composed of nucleons and
leptons under ~equilibrium and charge neutrality conditions is studied
with the Skyrme parametrizations shown to be consistent (CSkP) with the nuclear
matter, pure neutron matter, symmetry energy and its derivatives in a set of
constraints [Dutra {\it et al.}, Phys. Rev. C 85, 035201 (2012)]. The
predictions of these parametrizations on the tidal deformabilities related to
the GW170817 event are also examined. The CSkP that produce massive neutron
stars give a range of 11.86~\mbox{km} \leqslant R_{1.4} \leqslant
12.55~\mbox{km} for the canonical star radius, in agreement with other
theoretical predictions. It is shown that the CSkP are compatible with the
region of masses and radii obtained from the analysis of recent data from LIGO
and Virgo Collaboration (LVC). A correlation between dimensionless tidal
deformability and radius of the canonical star is found, namely, , with results for the CSkP compatible
with the recent range of from LVC. An
analysis of the graph shows that all the CSkP are
compatible with the recent bounds obtained by LVC. Finally, the universal
correlation between the moment of inertia and the deformability of a neutron
star, named as the \mbox{-Love} relation, is verified for the CSkP, that are
also shown to be consistent with the prediction for the moment of inertia of
the \mbox{PSR J0737-3039} primary component pulsar.Comment: 10 pages, 7 figure
Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
In a sample of 471 million BB events collected with the BABAR detector at the
PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is
either e+e- or mu+mu-. We report results on partial branching fractions and
isospin asymmetries in seven bins of di-lepton mass-squared. We further present
CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi
resonance. We find no evidence for CP or lepton-flavor violation. The partial
branching fractions and isospin asymmetries are consistent with the Standard
Model predictions and with results from other experiments.Comment: 16 pages, 14 figures, accepted by Phys. Rev.
Search for a dark vector gauge boson decaying to using decays
We report a search for a dark vector gauge boson that couples to
quarks in the decay chain , . No signal is found and we set a
mass-dependent limit on the baryonic fine structure constant of in the mass range of 290 to 520 MeV/. This analysis is
based on a data sample of 976 fb collected by the Belle experiment at
the KEKB asymmetric-energy collider.Comment: 6 pages, 4 figure
Search for and a measurement of the branching fraction for
We search for the decay and measure the
branching fraction for using
121.4~ of data collected at the
resonance with the Belle detector at the KEKB asymmetric-energy
collider. The branching fraction is measured
to be , where is the fraction of
in events. Our result is in good
agreement with the theoretical predictions as well as with a recent measurement
from LHCb. We observe no statistically significant signal for the decay
and set a confidence-level upper
limit on its branching fraction at . This constitutes a
significant improvement over the previous result.Comment: 6 pages, 3 figure
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