406 research outputs found
Proposed reference models for atomic oxygen in the terrestrial atmosphere
A provisional Atomic Oxygen Reference model was derived from average monthly ozone profiles and the MSIS-86 reference model atmosphere. The concentrations are presented in tabular form for the altitude range 40 to 130 km
'It's a big deal, being given a person': why people who experience infertility may choose not to adopt
This article explores why individuals and couples who experience infertility and undergo treatment through new technologies do not subsequently go on to become parents via adoption. It does this in three ways: a review of the literature; interviews with those affected; and an online survey of views on adoption among people who have experienced infertility. It was found that couples do consider adoption alongside infertility treatment but it is usually a fallback choice. If adoption is to be perceived as an equal option, agencies need to offer support and advice at an earlier stage than is usual. Couples who are emotionally exhausted by medical interventions for their childlessness can then be helped off the infertility treadmill in order to become parents
On the possibility of measuring relativistic gravitational effects with a LAGEOS-LAGEOS II-OPTIS-mission
In this paper we wish to preliminary investigate if it would be possible to
use the orbital data from the proposed OPTIS mission together with those from
the existing geodetic passive SLR LAGEOS and LAGEOS II satellites in order to
perform precise measurements of some general relativistic
gravitoelectromagnetic effects, with particular emphasis on the Lense-Thirring
effect.Comment: Abridged version. 16 pages, no figures, 1 table. First results from
the GGM01C Earth gravity model. GRACE data include
Upper limit map of a background of gravitational waves (Physical Review D - Particles, Fields, Gravitation and Cosmology (2007) 76, (082003))
This paper was published online on 29 October 2007 with a formatting error in the fiftieth affiliation in the author list.The affiliation should read as ‘‘University of Western Australia, Crawley, WA 6009, Australia.’’ The affiliation has beencorrected as of 4 March 2008. The affiliation is incorrect in the printed version of the journal
Congressional Seat Swings: Revisiting Exposure in House Elections
Oppenheimer, Stimson, and Waterman's exposure thesis of partisan change contends that shifts in the partisan composition of Congress are related to the long-term stability of the electoral system. Applying their exposure model to elections from 1962-1994 produces seat change estimates that generally follow the actual data pattern, but these estimates produce large predictive errors. When the exposure model is reestimated using data from 1962-1994, exposure is not significantly related to partisan seat swings. This article advances a seat change model that relies on an alter nate measure of exposure: the net exposure of the president's party in open seats. Open-seat exposure is significantly related to the partisan seat swing, and substantially improves on the economic evaluation/surge and-decline/ exposure model of seat change. In an era of high incumbent security and strategic retirement from Congress, the balance of open seats is a better indicator of partisan vulnerability, and better reflects the nature of partisan exposure.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
All-sky LIGO Search for Periodic Gravitational Waves in the Early S5 Data
We report on an all-sky search with the LIGO detectors for periodic
gravitational waves in the frequency range 50--1100 Hz and with the frequency's
time derivative in the range -5.0E-9 Hz/s to zero. Data from the first eight
months of the fifth LIGO science run (S5) have been used in this search, which
is based on a semi-coherent method (PowerFlux) of summing strain power.
Observing no evidence of periodic gravitational radiation, we report 95%
confidence-level upper limits on radiation emitted by any unknown isolated
rotating neutron stars within the search range. Strain limits below 1.E-24 are
obtained over a 200-Hz band, and the sensitivity improvement over previous
searches increases the spatial volume sampled by an average factor of about 100
over the entire search band. For a neutron star with nominal equatorial
ellipticity of 1.0E-6, the search is sensitive to distances as great as 500
pc--a range that could encompass many undiscovered neutron stars, albeit only a
tiny fraction of which would likely be rotating fast enough to be accessible to
LIGO. This ellipticity is at the upper range thought to be sustainable by
conventional neutron stars and well below the maximum sustainable by a strange
quark star.Comment: 6 pages, 1 figur
Search for Gravitational Wave Bursts from Soft Gamma Repeaters
We present the results of a LIGO search for short-duration gravitational
waves (GWs) associated with Soft Gamma Repeater (SGR) bursts. This is the first
search sensitive to neutron star f-modes, usually considered the most efficient
GW emitting modes. We find no evidence of GWs associated with any SGR burst in
a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190
lesser events from SGR 1806-20 and SGR 1900+14 which occurred during the first
year of LIGO's fifth science run. GW strain upper limits and model-dependent GW
emission energy upper limits are estimated for individual bursts using a
variety of simulated waveforms. The unprecedented sensitivity of the detectors
allows us to set the most stringent limits on transient GW amplitudes published
to date. We find upper limit estimates on the model-dependent isotropic GW
emission energies (at a nominal distance of 10 kpc) between 3x10^45 and 9x10^52
erg depending on waveform type, detector antenna factors and noise
characteristics at the time of the burst. These upper limits are within the
theoretically predicted range of some SGR models.Comment: 6 pages, 1 Postscript figur
Astrophysically Triggered Searches for Gravitational Waves: Status and Prospects
In gravitational-wave detection, special emphasis is put onto searches that
focus on cosmic events detected by other types of astrophysical observatories.
The astrophysical triggers, e.g. from gamma-ray and X-ray satellites, optical
telescopes and neutrino observatories, provide a trigger time for analyzing
gravitational wave data coincident with the event. In certain cases the
expected frequency range, source energetics, directional and progenitor
information is also available. Beyond allowing the recognition of gravitational
waveforms with amplitudes closer to the noise floor of the detector, these
triggered searches should also lead to rich science results even before the
onset of Advanced LIGO. In this paper we provide a broad review of LIGO's
astrophysically triggered searches and the sources they target
First LIGO search for gravitational wave bursts from cosmic (super)strings
We report on a matched-filter search for gravitational wave bursts from
cosmic string cusps using LIGO data from the fourth science run (S4) which took
place in February and March 2005. No gravitational waves were detected in 14.9
days of data from times when all three LIGO detectors were operating. We
interpret the result in terms of a frequentist upper limit on the rate of
gravitational wave bursts and use the limits on the rate to constrain the
parameter space (string tension, reconnection probability, and loop sizes) of
cosmic string models.Comment: 11 pages, 3 figures. Replaced with version submitted to PR
First joint search for gravitational-wave bursts in LIGO and GEO600 data
We present the results of the first joint search for gravitational-wave
bursts by the LIGO and GEO600 detectors. We search for bursts with
characteristic central frequencies in the band 768 to 2048 Hz in the data
acquired between the 22nd of February and the 23rd of March, 2005 (fourth LSC
Science Run - S4). We discuss the inclusion of the GEO600 data in the
Waveburst-CorrPower pipeline that first searches for coincident excess power
events without taking into account differences in the antenna responses or
strain sensitivities of the various detectors. We compare the performance of
this pipeline to that of the coherent Waveburst pipeline based on the maximum
likelihood statistic. This likelihood statistic is derived from a coherent sum
of the detector data streams that takes into account the antenna patterns and
sensitivities of the different detectors in the network. We find that the
coherentWaveburst pipeline is sensitive to signals of amplitude 30 - 50%
smaller than the Waveburst-CorrPower pipeline. We perform a search for
gravitational-wave bursts using both pipelines and find no detection candidates
in the S4 data set when all four instruments were operating stably.Comment: 30 pages, 8 figure
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