366 research outputs found
Possible large phase in psi(2S) -> 1-0- Decays
The strong and the electromagnetic amplitudes are analyzed on the basis of
the measurements of J/psi, psi(2S) -> 1-0- in e+e- experiments. The currently
available experimental information is revised with inclusion of the
contribution from e+e- -> gamma * -> 1-0- . The study shows that a large phase
around minus 90 degree between the strong and the electromagnetic amplitudes
could not be ruled out by the experimental data for psi(2S).Comment: 4 page
Dynamical features of reaction-diffusion fronts in fractals
The speed of front propagation in fractals is studied by using (i) the reduction of the reaction-transport equation into a Hamilton-Jacobi equation and (ii) the local-equilibrium approach. Different equations proposed for describing transport in fractal media, together with logistic reaction kinetics, are considered. Finally, we analyze the main features of wave fronts resulting from this dynamic process, i.e., why they are accelerated and what is the exact form of this acceleration
B -> X_s gamma gamma and B_s -> gamma gamma in supersymmetry with broken R-parity
We examine the effects of R-parity violating (RPV) supersymmetry on the
two-photon B decays B -> X_s gamma gamma and B_s -> gamma gamma. We find that,
although there are many one-loop RPV diagrams that can contribute to these
two-photon B decays, the RPV effect is dominated by a single diagram. This
diagram, named here lambda-irreducible, has a distinct topology which is
irrelevant for the b -> s gamma amplitude at one-loop and has thus a negligible
effect on the one-photon decay B -> X_s gamma. We show that the
lambda-irreducible RPV diagram can give BR(B_s -> gamma gamma) ~ 5*10^(-6) and
BR(B -> X_s gamma gamma) ~ 6*10^(-7), which is about 16 and 5 times larger than
the SM values, respectively. Although the enhancement to the decay width of B
-> X_s gamma gamma is not that dramatic, we find that the energy distribution
of the two photons is appreciably different from the SM, due to new threshold
effects caused by the distinct topology of the RPV lambda-irreducible diagram.
Moreover, this diagram significantly changes the forward-backward asymmetry
with respect to the softer photon in B -> X_s gamma gamma. Thus, the RPV effect
in B -> X_s gamma gamma can be discerned using these observables.Comment: 12 pages, 6 figure
The Emergence of Hospital Federations: An Integration of Perspectives from Organizational Theory
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68464/2/10.1177_107755878704400206.pd
Updated Reach of the CERN LHC and Constraints from Relic Density, b->s gamma and a(mu) in the mSUGRA Model
{We present an updated assessment of the reach of the CERN LHC pp collider
for supersymmetric matter in the context of the minimal supergravity (mSUGRA)
model. In addition to previously examined channels, we also include signals
with an isolated photon or with a leptonically decaying Z boson. For an
integrated luminosity of 100 fb^{-1}, values of m_{1/2}\sim 1400 GeV can be
probed for small m_0, corresponding to a gluino mass of m_{\tg}\sim 3 TeV. For
large m_0, in the hyperbolic branch/focus point region, m_{1/2}\sim 700 GeV can
be probed, corresponding to m_{\tg}\sim 1800 GeV. We also map out parameter
space regions preferred by the measured values of the dark matter relic
density, the b\to s\gamma decay rate, and the muon anomalous magnetic moment
a_\mu, and discuss how SUSY might reveal itself in these regions. We find the
CERN LHC can probe the entire stau co-annihilation region and also most of the
heavy Higgs annihilation funnel allowed by WMAP data, except for some range of
large m_0 and m_{1/2} if \tan\beta \agt 50.Comment: 22 page latex file including 10 EPS figures; bug fix in relic density
code modifies figures in co-annihilation regio
The Role of Radioactivities in Astrophysics
I present both a history of radioactivity in astrophysics and an introduction
to the major applications of radioactive abundances to astronomy
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
Psychology and aggression
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68264/2/10.1177_002200275900300301.pd
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