532 research outputs found
Primary Particle Type of the Most Energetic Fly's Eye Air Shower
The longitudinal profile of the most energetic cosmic-ray air shower measured
so far, the event recorded by the Fly's Eye detector with a reconstructed
primary energy of about 320 EeV, is compared to simulated shower profiles. The
calculations are performed with the CORSIKA code and include primary photons
and different hadron primaries. For primary photons, preshower formation in the
geomagnetic field is additionally treated in detail. For primary hadrons, the
hadronic interaction models QGSJET01 and SIBYLL2.1 have been employed. The
predicted longitudinal profiles are compared to the observation. A method for
testing the hypothesis of a specific primary particle type against the measured
profile is described which naturally takes shower fluctuations into account.
The Fly's Eye event is compatible with any assumption of a hadron primary
between proton and iron nuclei in both interaction models, although differences
between QGSJET01 and SIBYLL2.1 in the predicted profiles of lighter nuclei
exist. The primary photon profiles differ from the data on a level of ~1.5
sigma. Although not favoured by the observation, the primary photon hypothesis
can not be rejected for this particular event.Comment: 20 pages, 8 figures; v2 matches version accepted by Astroparticle
Physic
A redox-sensitive loop regulates plasminogen activator inhibitor type 2 (PAI-2) polymerization
Atmospheric Profiles at the Southern Pierre Auger Observatory and their Relevance to Air Shower Measurement
The dependence of atmospheric conditions on altitude and time have to be
known at the site of an air shower experiment for accurate reconstruction of
extensive air showers and their simulations. The height-profile of atmospheric
depth is of particular interest as it enters directly into the reconstruction
of longitudinal shower development and of the primary energy and mass of cosmic
rays. For the southern part of the Auger Observatory, the atmosphere has been
investigated in a number of campaigns with meteorological radio soundings and
with continuous measurements of ground-based weather stations. Focussing on
atmospheric depth and temperature profiles, temporal variations are described
and monthly profiles are developed. Uncertainties of the monthly atmospheres
that are currently applied in the Auger reconstruction are discussed.Comment: To be published in Proceedings of 29th International Cosmic Ray
Conference (ICRC) 2005, Pune, Indi
Views and experiences of managing eczema:systematic review and thematic synthesis of qualitative studies*
Background: The number of qualitative studies on eczema has increased rapidly in recent years. Systematically reviewing these can provide greater understandings of people’s perceptions of eczema and eczema treatments. Objectives: We sought to systematically review and thematically synthesize qualitative studies exploring views and experiences of people with eczema and parents/carers of children with eczema. Methods: We searched MEDLINE, EMBASE, PsycINFO and CINAHL from the earliest date available to February 2019. We selected papers focusing on views and experiences of eczema and eczema treatments, and barriers/facilitators to eczema self-management. We excluded papers focusing on health service provision models or health professionals’ views. Results: We synthesized 39 papers (reporting 32 studies) from 13 countries. We developed four analytical themes: (1) Eczema not viewed as a long-term condition; (2) Significant psychosocial impact not acknowledged by others; (3) Hesitancy (patient/carer uncertainty) about eczema treatments; and (4) Insufficient information and advice. Our findings suggest that people with eczema and their carers experience frustration at having to manage a condition that is often seen by others as mundane but has significant psychosocial impact and is difficult to manage due to concerns about, and burden of, treatment. This frustration can be exacerbated by experiences of conflicting and/or insufficient information and advice from health professionals, family and others. Conclusions: Effective self-management of eczema could be supported by addressing beliefs and concerns about treatments; seeking positive ways to promote a ‘control not cure’ message; acknowledging psychosocial impacts of eczema and treatment burden; and providing clear consistent advice or signposting towards reliable information.</p
Searching for New Physics Through AMO Precision Measurements
We briefly review recent experiments in atomic, molecular, and optical
physics using precision measurements to search for physics beyond the Standard
Model. We consider three main categories of experiments: searches for changes
in fundamental constants, measurements of the anomalous magnetic moment of the
electron, and searches for an electric dipole moment of the electron.Comment: Prepared for Comments on AMO Physics at Physica Script
Cross Section Limits for the Pb(Kr,n)118 Reaction
In April-May, 2001, the previously reported experiment to synthesize element
118 using the Pb(Kr,n)118 reaction was repeated. No
events corresponding to the synthesis of element 118 were observed with a total
beam dose of 2.6 x 10 ions. The simple upper limit cross sections (1
event) were 0.9 and 0.6 pb for evaporation residue magnetic rigidities of 2.00
and 2.12 , respectively. A more detailed cross section calculation,
accounting for an assumed narrow excitation function, the energy loss of the
beam in traversing the target and the uncertainty in the magnetic rigidity of
the Z=118 recoils is also presented. Re-analysis of the primary data files from
the 1999 experiment showed the reported element 118 events are not in the
original data. The current results put constraints on the production cross
section for synthesis of very heavy nuclei in cold fusion reactions.Comment: 7 pages, 2 figures. Submitted to EPJ
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