8,608 research outputs found
Mixing in the D0 system - Results from collider experiments
Mixing in the D0 system may provide a sensitive probe for new physics beyond
the Standard Model (SM) but has so far eluded experimental observation. The SM
predictions are typically small (< 10^{-3}) for the mixing parameters x, y
which, in the absence of charge-parity (CP) symmetry violation, measure the
mass (x= Delta(m)/Gamma) and lifetime (y= Delta(Gamma)/2Gamma) difference of
the CP eigenstates in the D0 system. The asymmetric B-factory experiments BABAR
and Belle open up the opportunity of measuring x, y with unprecedented
statistical precision and sample purities. Results from BABAR and Belle, and
from CLEO are reviewed.Comment: 28 pages, 7 figures, typos correcte
Transition from radiatively inefficient to cooling dominated phase in two temperature accretion discs around black holes
We investigate the transition of a radiatively inefficient phase of a viscous
two temperature accreting flow to a cooling dominated phase and vice versa
around black holes. Based on a global sub-Keplerian accretion disc model in
steady state, including explicit cooling processes self-consistently, we show
that general advective accretion flow passes through various phases during its
infall towards a black hole. Bremsstrahlung, synchrotron and inverse
Comptonization of soft photons are considered as possible cooling mechanisms.
Hence the flow governs a much lower electron temperature ~10^8 - 10^{9.5}K
compared to the hot protons of temperature ~10^{10.2} - 10^{11.8}K in the range
of the accretion rate in Eddington units 0.01 - 100. Therefore, the solutions
may potentially explain the hard X-rays and the gamma-rays emitted from AGNs
and X-ray binaries. We finally compare the solutions for two different regimes
of viscosity and conclude that a weakly viscous flow is expected to be cooling
dominated compared to its highly viscous counterpart which is radiatively
inefficient. The flow is successfully able to reproduce the observed
luminosities of the under-fed AGNs and quasars (e.g. Sgr A*), ultra-luminous
X-ray sources (e.g. SS433), as well as the highly luminous AGNs and
ultra-luminous quasars (e.g. PKS 0743-67) at different combinations of the mass
accretion rate and ratio of specific heats.Comment: 13 pages including 8 figures; couple of typos corrected; to appear in
Research in Astronomy and Astrophysic
Morphine Metabolism in Human Skin Microsomes
For patients with severe skin wounds, topically applied morphine is an option to induce efficient analgesia due to the presence of opioid receptors in the skin. However, for topical administration it is important to know whether the substance is biotransformed in the skin as this can eventually reduce the concentration of the active agent considerably. We use skin microsomes to elucidate the impact of skin metabolism on the activity of topically applied morphine. We are able to demonstrate that morphine is only glucuronidated in traces, indicating that the biotransformation in the skin can be neglected when morphine is applied topically. Hence, there is no need to take biotransformation into account when setting up the treatment regimen. Copyright (C) 2012 S. Karger AG, Base
Methods for the Study of Transverse Momentum Differential Correlations
We introduce and compare three differential correlation functions for the
study of transverse momentum correlation in and collisions. These
consist of {\it inclusive}, {\it event-wise} and a differential version of the
correlation measure introduced by Gavin \cite{Gavin} for
experimental study of the viscosity per unit entropy of the matter produced in
collisions. We study the quantitative difference between the three
observables on the basis of PYTHIA simulations of collisions and
collisions consisting of an arbitrary superposition of collision events
at 200 GeV. We observe that {\it inclusive} and {\it event-wise}
correlation functions are remarkably identical to each other where as the
observable differs from the two. We study the robustness and
efficiency dependencies of these observables based on truncated Taylor
expansions in efficiency in collisions and on the basis of Monte Carlo
simulation using an adhoc detector efficiency parameterization. We find that
all the three observables are essentially independent of detector efficiency.
We additionally study the scaling of the correlation measures and find all the
observables exhibit an approximate dependence of the number of
participants ({\it N}) in collisions. Finally, we study the impact of
flow-like anisotropy on the {\it inclusive} correlation function and find flow
imparts azimuthal modulations similar to those observed with two-particle
densities.Comment: 19 pages, 8 figure
Investigating texture six zero lepton mass matrices
Texture six zero Fritzsch like as well as non Fritzsch like hermitian lepton
mass matrices (144 combinations in all) have been investigated for both
Majorana and Dirac neutrinos for their compatibility with the current neutrino
oscillation data, keeping in mind the hierarchy of neutrino masses. All the
combinations considered here for Majorana neutrino masses are ruled out by the
existing data in the case of inverted hierarchy and degenerate scenario. For
Majorana neutrinos with normal hierarchy, only 16 combinations can accommodate
the experimental data. Assuming neutrinos to be Dirac particles, normal
hierarchy, inverted hierarchy as well as degenerate neutrinos are ruled out for
all combinations of texture 6 zero hermitian mass matrices.Comment: 14 pages, 2 figure
- …