19,555 research outputs found
Theoretical correction to the neutral meson asymmetry
Certain types of asymmetries in neutral meson physics have not been treated
properly, ignoring the difference of normalization factors with an assumption
of the equality of total decay width. Since the corrected asymmetries in
meson are different from known asymmetries by a shift in the first order of CP-
and CPT-violation parameters, experimental data should be analyzed with the
consideration of this effect as in meson physics.Comment: 7 page
Enhancing entanglement detection of quantum optical frequency combs via stimulated emission
We investigate the performance of a certain nonclassicality identifier,
expressed via integrated second-order intensity moments of optical fields, in
revealing bipartite entanglement of quantum-optical frequency combs (QOFCs),
which are generated in both spontaneous and stimulated parametric
down-conversion processes. We show that, by utilizing that nonclassicality
identifier, one can well identify the entanglement of the QOFC directly from
the experimentally measured intensity moments without invoking any state
reconstruction techniques or homodyne detection. Moreover, we demonstrate that
the stimulated generation of the QOFC improves the entanglement detection of
these fields with the nonclassicality identifier. Additionally, we show that
the nonclassicality identifier can be expressed in a factorized form of
detectors quantum efficiencies and the number of modes, if the QOFC consists of
many copies of the same two-mode twin beam. As an example, we apply the
nonclassicality identifier to two specific types of QOFC, where: (i) the QOFC
consists of many independent two-mode twin beams with non-overlapped spatial
frequency modes, and (ii) the QOFC contains entangled spatial frequency modes
which are completely overlapped, i.e., each mode is entangled with all the
remaining modes in the system. We show that, in both cases, the nonclassicality
identifier can reveal bipartite entanglement of the QOFC including noise, and
that it becomes even more sensitive for the stimulated processes.Comment: 11 p., 8 fig
Techniques for mass production of large-sized GEM foil at Korea for CMS phase-2 upgrade
This study presents techniques for the mass production of large-sized GEM
foils for the CMS phase-2 upgrade in Korea. The foil production facility is
designed with a focus on mass production, including the adoption of the
double-mask technique. A polyimide wet etching technology that uses mono
ethanolamine is reported, providing a safer working environment due to its
lower inhalation toxicity compared to ethylene diamine. The study also covers
the denaturation of the etchant over time and the process of retuning. Finally,
R&D results on soldering surface mount resistors with hot air for faster
production are discussed.Comment: Proceedings of MPGD 202
Temporal Analysis of Language through Neural Language Models
We provide a method for automatically detecting change in language across
time through a chronologically trained neural language model. We train the
model on the Google Books Ngram corpus to obtain word vector representations
specific to each year, and identify words that have changed significantly from
1900 to 2009. The model identifies words such as "cell" and "gay" as having
changed during that time period. The model simultaneously identifies the
specific years during which such words underwent change
Type IIP supernova light curves affected by the acceleration of red supergiant winds
We introduce the first synthetic light-curve model set of Type IIP supernovae
exploded within circumstellar media in which the acceleration of the red
supergiant winds is taken into account. Because wind acceleration makes the
wind velocities near the progenitors low, the density of the immediate vicinity
of the red supergiant supernova progenitors can be higher than that
extrapolated by using a constant terminal wind velocity. Therefore, even if the
mass-loss rate of the progenitor is relatively low, it can have a dense
circumstellar medium at the immediate stellar vicinity and the early light
curves of Type IIP supernovae are significantly affected by it. We adopt a
simple beta velocity law to formulate the wind acceleration. We provide
bolometric and multicolor light curves of Type IIP supernovae exploding within
such accelerated winds from the combinations of three progenitors, 12 - 16
Msun; five beta, 1-5; seven mass-loss rates, 1e-5 - 1e-2 Msun/yr; and four
explosion energies, 0.5e51 - 2e51 erg. All the light curve models are available
at https://goo.gl/o5phYb. When the circumstellar density is sufficiently high,
our models do not show a classical shock breakout as a consequence of the
interaction with the dense and optically-thick circumstellar media. Instead,
they show a delayed 'wind breakout', substantially affecting early light curves
of Type IIP supernovae. We find that the mass-loss rates of the progenitors
need to be 1e-3 - 1e-2 Msun/yr to explain typical rise times of 5 - 10 days in
Type IIP supernovae assuming a dense circumstellar radius of 1e15 cm.Comment: 12 pages, 9 figures, 2 tables, accepted by Monthly Notices of the
Royal Astronomical Societ
Ultra-stripped Type Ic supernovae from close binary evolution
Recent discoveries of weak and fast optical transients raise the question of
their origin. We investigate the minimum ejecta mass associated with
core-collapse supernovae (SNe) of Type Ic. We show that mass transfer from a
helium star to a compact companion can produce an ultra-stripped core which
undergoes iron core collapse and leads to an extremely fast and faint SN Ic. In
this Letter, a detailed example is presented in which the pre-SN stellar mass
is barely above the Chandrasekhar limit, resulting in the ejection of only
~0.05-0.20 M_sun of material and the formation of a low-mass neutron star. We
compute synthetic light curves of this case and demonstrate that SN 2005ek
could be explained by our model. We estimate that the fraction of such
ultra-stripped to all SNe could be as high as 0.001-0.01. Finally, we argue
that the second explosion in some double neutron star systems (for example, the
double pulsar PSR J0737-3039B) was likely associated with an ultra-stripped SN
Ic.Comment: ApJ Letters, in press, 6 pages, 5 figures (emulateapj style). Very
minor changes to match printed version. Follow DOI link below for online
published versio
Outcomes of psychological therapies for prisoners with mental health problems: a systematic review and meta-analysis
Objective: Prisoners worldwide have substantial mental health needs, but the efficacy of psychological therapy in prisons is unknown. We aimed to systematically review psychological therapies with mental health outcomes in prisoners and qualitatively summarize difficulties in conducting randomized clinical trials (RCTs).
Method: We systematically identified RCTs of psychological therapies with mental health outcomes in prisoners (37 studies). Effect sizes were calculated and meta-analyzed. Eligible studies were assessed for quality. Subgroup and metaregression analyses were conducted to examine sources of between-study heterogeneity. Thematic analysis reviewed difficulties in conducting prison RCTs.
Results: In 37 identified studies, psychological therapies showed a medium effect size (0.50, 95% CI [0.34, 0.66]) with high levels of heterogeneity with the most evidence for CBT and mindfulness-based trials. Studies that used no treatment (0.77, 95% CI [0.50, 1.03]) or waitlist controls (0.71, 95% CI [0.43, 1.00]) had larger effect sizes than those that had treatment-as-usual or other psychological therapies as controls (0.21, 95% CI [0.01, 0.41]). Effects were not sustained on follow-up at 3 and 6 months. No differences were found between group and individual therapy, or different treatment types. The use of a fidelity measure was associated with lower effect sizes. Qualitative analysis identified difficulties with follow-up and institutional constraints on scheduling and implementation of trials.
Conclusions: CBT and mindfulness-based therapies are modestly effective in prisoners for depression and anxiety outcomes. In prisons with existing psychological therapies, more evidence is required before additional therapies can be recommended
Renormalization analysis of intermittency in two coupled maps
The critical behavior for intermittency is studied in two coupled
one-dimensional (1D) maps. We find two fixed maps of an approximate
renormalization operator in the space of coupled maps. Each fixed map has a
common relavant eigenvaule associated with the scaling of the control parameter
of the uncoupled one-dimensional map. However, the relevant ``coupling
eigenvalue'' associated with coupling perturbation varies depending on the
fixed maps. These renormalization results are also confirmed for a
linearly-coupled case.Comment: 11 pages, RevTeX, 2 eps figure
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