160 research outputs found
HELAS and MadGraph with spin-3/2 particles
Fortran subroutines to calculate helicity amplitudes with massive spin-3/2
particles, such as massive gravitinos, which couple to the standard model and
supersymmetric particles via the supercurrent, are added to the HELAS (HELicity
Amplitude Subroutines) library. They are coded in such a way that arbitrary
amplitudes with external gravitinos can be generated automatically by MadGraph,
after slight modifications. All the codes have been tested carefully by making
use of the gauge invariance of the helicity amplitudes.Comment: 12 pages, 4 figures; sections rearranged, typos corrected, version to
appear in EPJ
Simulating spin-3/2 particles at colliders
Support for interactions of spin-3/2 particles is implemented in the
FeynRules and ALOHA packages and tested with the MadGraph 5 and CalcHEP event
generators in the context of three phenomenological applications. In the first,
we implement a spin-3/2 Majorana gravitino field, as in local supersymmetric
models, and study gravitino and gluino pair-production. In the second, a
spin-3/2 Dirac top-quark excitation, inspired from compositness models, is
implemented. We then investigate both top-quark excitation and top-quark
pair-production. In the third, a general effective operator for a spin-3/2
Dirac quark excitation is implemented, followed by a calculation of the angular
distribution of the s-channel production mechanism.Comment: 20 pages, 7 figure
A Hardy's Uncertainty Principle Lemma in Weak Commutation Relations of Heisenberg-Lie Algebra
In this article we consider linear operators satisfying a generalized
commutation relation of a type of the Heisenberg-Lie algebra. It is proven that
a generalized inequality of the Hardy's uncertainty principle lemma follows.
Its applications to time operators and abstract Dirac operators are also
investigated
Improvement of psychiatristsâ clinical knowledge of the treatment guidelines for schizophrenia and major depressive disorders using the âEffectiveness of Guidelines for Dissemination and Education in Psychiatric Treatment (EGUIDE)â project: A nationwide dissemination, education, and evaluation study
© 2019 The Authors. Psychiatry and Clinical Neurosciences published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Psychiatry and Neurology Aim: Although treatment guidelines for pharmacological therapy for schizophrenia and major depressive disorder have been issued by the Japanese Societies of Neuropsychopharmacology and Mood Disorders, these guidelines have not been well applied by psychiatrists throughout the nation. To address this issue, we developed the âEffectiveness of Guidelines for Dissemination and Education in Psychiatric Treatment (EGUIDE)â integrated education programs for psychiatrists to disseminate the clinical guidelines. Additionally, we conducted a systematic efficacy evaluation of the programs. Methods: Four hundred thirteen out of 461 psychiatrists attended two 1-day educational programs based on the treatment guidelines for schizophrenia and major depressive disorder from October 2016 to March 2018. We measured the participantsâ clinical knowledge of the treatment guidelines using self-completed questionnaires administered before and after the program to assess the effectiveness of the programs for improving knowledge. We also examined the relation between the participantsâ demographics and their clinical knowledge scores. Results: The clinical knowledge scores for both guidelines were significantly improved after the program. There was no correlation between clinical knowledge and participant demographics for the program on schizophrenia; however, a weak positive correlation was found between clinical knowledge and the years of professional experience for the program on major depressive disorder. Conclusion: Our results provide evidence that educational programs on the clinical practices recommended in guidelines for schizophrenia and major depressive disorder might effectively improve participantsâ clinical knowledge of the guidelines. These data are encouraging to facilitate the standardization of clinical practices for psychiatric disorders
Associated production of light gravitinos in e^+e^- and e^-\gamma collisions
Light gravitino productions in association with a neutralino (selectron) in
e^+e^- (e^-\gamma) collisions are restudied in a scenario that the lightest
supersymmetric particle is a gravitino and the produced neutralino (selectron)
promptly decays into a photon (electron) and a gravitino. We explicitly give
the helicity amplitudes for the production processes by using the effective
goldstino interaction Lagrangian, and present the cross sections with different
collision energies and mass spectra. We also examine selection efficiencies by
kinematical cuts and beam polarizations for the signal and background
processes, and show that the energy and angular distributions of the photon
(electron) can explore the mass of the t-channel exchange particle as well as
the mass of the decaying particle at a future e^+e^- (e^-\gamma) collider.Comment: 12 pages, 12 figures, 4 tables; references added, version to appear
in EPJ
Weak itinerant ferromagnetism in Heusler type Fe2VAl0.95
We report measurements of the magnetic, transport and thermal properties of
the Heusler type compound Fe2VAl0.95. We show that while stoichiometric Fe2VAl
is a non-magnetic semi-metal a 5% substitution on the Al-site with the 3d
elements Fe and V atoms leads to a ferromagnetic ground state with a Curie
temperature TC = 33+-3 K and a small ordered moment ms = 0.12 mB/Fe in
Fe2VAl0.95. The reduced value of the ratio ms/mp = 0.08, where mp = 1.4 mB/Fe
is the effective Curie-Weiss moment, together with the analysis of the
magnetization data M(H,T), show magnetism is of itinerant nature. The specific
heat shows an unusual temperature variation at low temperatures with an
enhanced Sommerfeld coefficient, g = 12 mJK-2mol-1. The resistivity, r(T), is
metallic and follows a power law behavior r(T) = r0+AT^n with n = 1.5 below TC.
With applying pressure, TC decreases with the rate of (1/TC)(dTC /dP) = -0.061
GPa-1. We conclude substitution on the Al-site with Fe and V atoms results in
itinerant ferromagnetism with a low carrier density.Comment: 27 pages, 9 figure
HELAS and MadGraph with goldstinos
Fortran subroutines to calculate helicity amplitudes with goldstinos, which
appear as the longitudinal modes of massive gravitinos in high energy
processes, are added to the HELAS (HELicity Amplitude Subroutines) library.
They are coded in such a way that arbitrary amplitudes with external goldstinos
can be generated automatically by MadGraph, after slight modifications. All the
codes have been tested carefully by making use of the goldstino equivalence
theorem and the gauge invariance of the helicity amplitudes. Hadronic total
cross sections for associated gravitino productions with a gluino and a squark
are also presented.Comment: 9 pages, 6 figures; a footnote and a reference added, version to
appear in EPJ
Collider signatures of goldstini in gauge mediation
We investigate the collider signatures of the multiple goldstini scenario in
the framework of gauge mediation. This class of models is characterized by a
visible sector (e.g. the MSSM or any extension) coupled by gauge interactions
to more than one SUSY breaking sector. The spectrum consists of a light
gravitino LSP, behaving as a goldstino, and a number of neutral fermions (the
pseudo-goldstini) with a mass between that of the LSP and that of the lightest
particle of the observable sector (LOSP). We consider the two situations where
the LOSP is either a gaugino-like neutralino or a stau and we assume only one
pseudo-goldstino of a mass of O(100) GeV. The coupling of the LOSP to the
pseudo-goldstino can be enhanced with respect to those of the gravitino giving
rise to characteristic signatures. We show that the decay modes of the LOSP
into a SM particle and a pseudo-goldstino can be significant. For both LOSP
scenarios we analyze (pseudo)-goldstini production at colliders. Compared to
standard gauge mediation the final state spectrum is softer and more
structured.Comment: v2: analysis of the stau LOSP scenario added, sections rearranged,
and Introduction and Conclusions rewritten to include the added scenario.
Version to appear in JHE
The Sno Oncogene Antagonizes Wingless Signaling during Wing Development in Drosophila
The Sno oncogene (Snoo or dSno in Drosophila) is a highly conserved protein and a well-established antagonist of Transforming Growth Factor-ÎČ signaling in overexpression assays. However, analyses of Sno mutants in flies and mice have proven enigmatic in revealing developmental roles for Sno proteins. Thus, to identify developmental roles for dSno we first reconciled conflicting data on the lethality of dSno mutations. Then we conducted analyses of wing development in dSno loss of function genotypes. These studies revealed ectopic margin bristles and ectopic campaniform sensilla in the anterior compartment of the wing blade suggesting that dSno functions to antagonize Wingless (Wg) signaling. A subsequent series of gain of function analyses yielded the opposite phenotype (loss of bristles and sensilla) and further suggested that dSno antagonizes Wg signal transduction in target cells. To date Sno family proteins have not been reported to influence the Wg pathway during development in any species. Overall our data suggest that dSno functions as a tissue-specific component of the Wg signaling pathway with modest antagonistic activity under normal conditions but capable of blocking significant levels of extraneous Wg, a role that may be conserved in vertebrates
Towards a Metric for the Assessment of Safety Critical Control Systems
There is a need for better integration of the fault tolerant and the control designs for safety critical systems such as aircraft. The dependability of current designs is assessed primarily with measures of the interconnection of fault tolerant components: the reliability function and the mean time to failure. These measures do not directly take into account the interaction of the fault tolerant components with the dynamics of the aircraft. In this paper, a first step to better integrate these designs is made. It is based on the observation that unstable systems are intrinsically unreliable and that a necessary condition for reliability is the existence of a stabilizing control law that depends on the interconnection of the working fault tolerant components. Since operation of a fault tolerant interconnection of digital computers in a harsh environment can result in transient errors, a methodology to analyze the mean square stability of the fault tolerant closed-loop system is presented. A definition for mean square stabilizability is then used to introduce the new dynamical system reliability concept. An example illustrates the effect on mean square stability of several fault tolerant design choices and illustrates possible dynamical system reliability plot
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