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Comment on an unusual event in the E594 detector from the direction of Cygnus X-3
A small array located near the 80 m/sup 2/ E594 neutrino detector at Fermilab had a two week run. The author makes two comments related to ultra high energy gamma ray physics. The first regards the question of angular resolution from muons. In general, the angle of a muon will not reflect the angle of the shower for reasons which include transverse momentum at production, multiple scattering in the atmosphere, multiple scattering in the detector and detector angular resolution. In multiple muon events, the angle between each muon and the average muon angle samples all of these deviations. Therefore, this is a good measure of the angular resolution of the shower using the muons on an event by event basis. The second comment regards an unusual event from Cygnus X-3
High-sensitivity imaging with multi-mode twin beams
Twin entangled beams produced by single-pass parametric down-conversion (PDC)
offer the opportunity to detect weak amount of absorption with an improved
sensitivity with respect to standard techniques which make use of classical
light sources. We propose a differential measurement scheme which exploits the
spatial quantum correlation of type II PDC to image a weak amplitude object
with a sensitivity beyond the standard quantum limit imposed by shot-noise.Comment: 13 pages, 8 figure
Psychosocial functioning in adolescents with and without borderline personality disorder.
Little is known about the psychosocial functioning of adolescents with borderline personality disorder (BPD). The main objective of this paper is to compare the psychosocial functioning of a group of adolescents with BPD to a group of psychiatrically healthy adolescents.
The present cross-sectional study included 104 adolescent inpatients with BPD, compared with 60 age-matched psychiatrically healthy comparison subjects. All participants were rigorously diagnosed using three semi-structured interviews: the Structured Clinical Interview for DSM-IV Childhood Diagnoses, the Revised Diagnostic Interview for Borderlines and the Childhood Interview for DSM-IV Borderline Personality. All subjects were also interviewed using the adolescent version of the Background Information Schedule to assess multiple facets of psychosocial functioning.
Adolescents with BPD rated their relationships with their parents as significantly less positive, were more likely to date, but spent more time alone than their healthy counterparts. In addition, adolescents with BPD reported significantly more problems at work and school (i.e. lower frequency of having a good work or school history, higher frequency of being suspended or expelled from school) and significantly lower rates of participation in extra-curricular activities than their healthy counterparts.
Taken together, the results of this study suggest that adolescents with BPD are more impaired in both the social and vocational areas of functioning than psychiatrically healthy comparison subjects. They might also suggest that an overlooked area of strength concerns their relationships with peers. Copyright © 2017 John Wiley & Sons, Ltd
The atmospheric charged kaon/pion ratio using seasonal variation methods
Observed since the 1950's, the seasonal effect on underground muons is a well
studied phenomenon. The interaction height of incident cosmic rays changes as
the temperature of the atmosphere changes, which affects the production height
of mesons (mostly pions and kaons). The decay of these mesons produces muons
that can be detected underground. The production of muons is dominated by pion
decay, and previous work did not include the effect of kaons. In this work, the
methods of Barrett and MACRO are extended to include the effect of kaons. These
efforts give rise to a new method to measure the atmospheric K/ ratio at
energies beyond the reach of current fixed target experiments. These methods
were applied to data from the MINOS far detector. A method is developed for
making these measurements at other underground detectors, including OPERA,
Super-K, IceCube, Baksan and the MINOS near detector.Comment: 15 pages, 4 figures, submitted to Astropart. Phy
Multivariate discrete distributions via sums and shares
In this article, we develop a sum and share decomposition to model multivariate discrete distributions, and more specifically multivariate count data that can be divided into a number of distinct categories. From a Poisson mixture model for the sum and a multinomial mixture model for the shares, a rich ensemble of properties, examples and relationships arises. As a main example, a seemingly new multivariate model involving a negative binomial sum and Polya shares is considered, previously seen only in the bivariate case, for which we present two contrasting applications. For other choices of the distribution of the sum, natural but novel discrete multivariate Liouville distributions emerge; an important special case of these is that of Schur constant distributions. Analogies and interactions with related continuous distributions are to the fore throughout
Cosmological Constraints on an Invisibly Decaying Higgs Boson
Working in the context of a proposal for collisional dark matter, we derive
bounds on the Higgs boson coupling to a stable light scalar
particle, which we refer to as phion (), required to solve problems with
small scale structure formation which arise in collisionless dark matter
models. We discuss the behaviour of the phion in the early universe for
different ranges of its mass. We find that a phion in the mass range of 100 MeV
is excluded and that a phion in the mass range of 1 GeV requires a large
coupling constant, g^{\prime} \gsim 2, and m_h \lsim 130 GeV in order to
avoid overabundance, in which case the invisible decay mode of the Higgs boson
would be dominant.Comment: 5 pages, 2 figures, Revtex style, changed conten
Cross-species chromosome painting in bats from Madagascar: the contribution of Myzopodidae to revealing ancestral syntenies in Chiroptera
The chiropteran fauna of Madagascar comprises eight of the 19 recognized families of bats, including the endemic Myzopodidae. While recent systematic studies of Malagasy bats have contributed to our understanding of the morphological and genetic diversity of the island’s fauna, little is known about their cytosystematics. Here we investigate karyotypic relationships among four species, representing four families of Chiroptera endemic to the Malagasy region using cross-species chromosome painting with painting probes of Myotis myotis: Myzopodidae (Myzopoda aurita, 2n=26), Molossidae (Mormopterus jugularis, 2n=48), Miniopteridae (Miniopterus griveaudi, 2n=46), and Vespertilionidae (Myotis goudoti, 2n=44). This study represents the first time a member of the family Myzopodidae has been investigated using chromosome painting. Painting probes of Myotis. myotis were used to delimit 30, 24, 23, and 22 homologous chromosomal segments in the genomes of Myzopoda aurita, Mormopterus jugularis, Miniopterus . griveaudi and Myotis . goudoti, respectively. Comparison of GTG-banded homologous chromosomes/chromosomal segments among the four species revealed the genome of M. aurita has been structured through 15 fusions of chromosomes and chromosomal segments of Myotis. myotis chromosomes leading to a karyotype consisting solely of bi-armed chromosomes. In addition, chromosome painting revealed a novel X-autosome translocation in Myzopoda. aurita. Comparison of our results with published chromosome maps provided further evidence for karyotypic conservatism within the genera Mormopterus, Miniopterus and Myotis. Mapping of chromosomal rearrangements onto a molecular consensus phylogeny revealed ancestral syntenies shared between Myzopoda and other bat species of the infraorders Pteropodiformes and Vespertilioniformes. Our study provides further evidence for the involvement of Robertsonian (Rb) translocations and fusions/fissions in chromosomal evolution within Chiroptera
Bi-Large Neutrino Mixing See-Saw Mass Matrix with Texture Zeros and Leptogenesis
We study constraints on neutrino properties from texture zeros in bi-large
mixing See-Saw mass matrix and also from leptogenesis. Texture zeros may occur
in the light (class a)) or in the heavy (class b)) neutrino mass matrices. Each
of these two classes has 5 different forms which can produce non-trivial three
generation mixing with at least one texture zero. We find that two types of
texture zero mass matrices in both class a) and class b) can be consistent with
present data on neutrino masses, mixing and produce the observed baryon
asymmetry of the universe. None of the neutrinos can have zero masses with the
lightest of the light neutrinos having a mass larger than about 0.039 eV for
class a) and 0.002 eV for class b). In these models although CKM CP violating
phase vanishes, non-zero Majorana phases, however, can exist and play an
important role in producing the observed baryon asymmetry in our universe
through leptogenesis mechanism. The requirement of producing the observed
baryon asymmetry can further distinguish different models and also restrict the
See-Saw scale to be in the range GeV.Comment: 21 pages, 7 figures revised version, some references added, to be
submitted to PR
Balloon Measurements of Cosmic Ray Muon Spectra in the Atmosphere along with those of Primary Protons and Helium Nuclei over Mid-Latitude
We report here the measurements of the energy spectra of atmospheric muons
and of the cosmic ray primary proton and helium nuclei in a single experiment.
These were carried out using the MASS superconducting spectrometer in a balloon
flight experiment in 1991. The relevance of these results to the atmospheric
neutrino anomaly is emphasized. In particular, this approach allows
uncertainties caused by the level of solar modulation, the geomagnetic cut-off
of the primaries and possible experimental systematics to be decoupled in the
comparison of calculated fluxes of muons to measured muon fluxes. The muon
observations cover the momentum and depth ranges of 0.3-40 GeV/c and 5-886
g/cmsquared, respectively. The proton and helium primary measurements cover the
rigidity range from 3 to 100 GV, in which both the solar modulation and the
geomagnetic cut-off affect the energy spectra at low energies.Comment: 31 pages, including 17 figures, simplified apparatus figure, to
appear in Phys. Rev.
Search for the Proton Decay Mode proton to neutrino K+ in Soudan 2
We have searched for the proton decay mode proton to neutrino K+ using the
one-kiloton Soudan 2 high resolution calorimeter. Contained events obtained
from a 3.56 kiloton-year fiducial exposure through June 1997 are examined for
occurrence of a visible K+ track which decays at rest into mu+ nu or pi+ pi0.
We found one candidate event consistent with background, yielding a limit,
tau/B > 4.3 10^{31} years at 90% CL with no background subtraction.Comment: 13 pages, Latex, 3 tables and 3 figures, Accepted by Physics Letters
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