323 research outputs found
Impact of 2009 American Recovery and Reinvestment Act (ARRA) health center investments on disadvantaged neighborhoods after recession
Background: Federally qualified health centers (FQHCs) are integral to the U.S. healthcare safety net and uniquely situated in disadvantaged neighborhoods. The 2009 American Recovery and Reinvestment Act (ARRA) invested $2 billion in FQHC stimulus during the Great Recession; but it remains unknown whether this investment was associated with extended benefits for disadvantaged neighborhoods. Methods: We used a propensity-score matched longitudinal design (2008-2012) to examine whether the 2009 ARRA FQHC investment was associated with local jobs and establishments recovery in FQHC neighborhoods. Job change data were obtained from the Longitudinal Employer-Household Dynamics (LEHD) survey and calculated as an annual rate per 1,000 population. Establishment change data were obtained from the National Neighborhood Data Archive (NaNDA) and calculated as an annual rate per 10,000 population. Establishment data included 4 establishment types: healthcare services, eating/drinking places, retail establishments, and grocery stores. Fixed effects were used to compare annual rates of jobs and establishments recovery between ARRA-funded FQHC census tracts and a matched control group. Results: Of 50,381 tracts, 2,223 contained ≥ 1 FQHC that received ARRA funding. A higher proportion of FQHC tracts had an extreme poverty designation (11.6% vs. 5.4%), high unemployment rate (45.4% vs. 30.3%), and > 50% minority racial/ethnic composition (48.1% vs. 36.3%). On average, jobs grew at an annual rate of 3.84 jobs per 1,000 population (95% CI: 3.62,4.06). In propensity-score weighted models, jobs in ARRA-funded tracts grew at a higher annual rate of 4.34 per 1,000 (95% CI: 2.56,6.12) relative to those with similar social vulnerability. We observed persistent decline in non-healthcare establishments (-1.35 per 10,000; 95% CI: -1.68,-1.02); but did not observe decline in healthcare establishments. Conclusions: Direct funding to HCs may be an effective strategy to support healthcare establishments and some jobs recovery in disadvantaged neighborhoods during recession, reinforcing the important multidimensional roles HCs play in these communities. However, HCs may benefit from additional investments that target upstream determinants of health to mitigate uneven recovery and neighborhood decline.</p
A Complete Spectroscopic Survey of the Milky Way satellite Segue 1: Dark matter content, stellar membership and binary properties from a Bayesian analysis
We introduce a comprehensive analysis of multi-epoch stellar line-of-sight
velocities to determine the intrinsic velocity dispersion of the ultrafaint
satellites of the Milky Way. Our method includes a simultaneous Bayesian
analysis of both membership probabilities and the contribution of binary
orbital motion to the observed velocity dispersion within a 14-parameter
likelihood. We apply our method to the Segue 1 dwarf galaxy and conclude that
Segue 1 is a dark-matter-dominated galaxy at high probability with an intrinsic
velocity dispersion of 3.7^{+1.4}_{-1.1} km/sec. The dark matter halo required
to produce this dispersion must have an average density of 2.5^{+4.1}_{-1.9}
solar mass/pc^3 within a sphere that encloses half the galaxy's stellar
luminosity. This is the highest measured density of dark matter in the Local
Group. Our results show that a significant fraction of the stars in Segue 1 may
be binaries with the most probable mean period close to 10 years, but also
consistent with the 180 year mean period seen in the solar vicinity at about 1
sigma. Despite this binary population, the possibility that Segue 1 is a bound
star cluster with the observed velocity dispersion arising from the orbital
motion of binary stars is disfavored by the multi-epoch stellar velocity data
at greater than 99% C.L. Finally, our treatment yields a projected
(two-dimensional) half-light radius for the stellar profile of Segue 1 of
28^{+5}_{-4} pc, in excellent agreement with photometric measurements.Comment: 15 pages, 19 figure
The Multi-Object, Fiber-Fed Spectrographs for SDSS and the Baryon Oscillation Spectroscopic Survey
We present the design and performance of the multi-object fiber spectrographs
for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon
Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999
on the 2.5-m aperture Sloan Telescope at Apache Point Observatory, the
spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II
surveys, enabling a wide variety of Galactic and extra-galactic science
including the first observation of baryon acoustic oscillations in 2005. The
spectrographs were upgraded in 2009 and are currently in use for BOSS, the
flagship survey of the third-generation SDSS-III project. BOSS will measure
redshifts of 1.35 million massive galaxies to redshift 0.7 and Lyman-alpha
absorption of 160,000 high redshift quasars over 10,000 square degrees of sky,
making percent level measurements of the absolute cosmic distance scale of the
Universe and placing tight constraints on the equation of state of dark energy.
The twin multi-object fiber spectrographs utilize a simple optical layout
with reflective collimators, gratings, all-refractive cameras, and
state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in
two channels over a bandpass covering the near ultraviolet to the near
infrared, with a resolving power R = \lambda/FWHM ~ 2000. Building on proven
heritage, the spectrographs were upgraded for BOSS with volume-phase
holographic gratings and modern CCD detectors, improving the peak throughput by
nearly a factor of two, extending the bandpass to cover 360 < \lambda < 1000
nm, and increasing the number of fibers from 640 to 1000 per exposure. In this
paper we describe the original SDSS spectrograph design and the upgrades
implemented for BOSS, and document the predicted and measured performances.Comment: 43 pages, 42 figures, revised according to referee report and
accepted by AJ. Provides background for the instrument responsible for SDSS
and BOSS spectra. 4th in a series of survey technical papers released in
Summer 2012, including arXiv:1207.7137 (DR9), arXiv:1207.7326 (Spectral
Classification), and arXiv:1208.0022 (BOSS Overview
The Sloan Digital Sky Survey Quasar Lens Search. IV. Statistical Lens Sample from the Fifth Data Release
We present the second report of our systematic search for strongly lensed
quasars from the data of the Sloan Digital Sky Survey (SDSS). From extensive
follow-up observations of 136 candidate objects, we find 36 lenses in the full
sample of 77,429 spectroscopically confirmed quasars in the SDSS Data Release
5. We then define a complete sample of 19 lenses, including 11 from our
previous search in the SDSS Data Release 3, from the sample of 36,287 quasars
with i<19.1 in the redshift range 0.6<z<2.2, where we require the lenses to
have image separations of 1"<\theta<20" and i-band magnitude differences
between the two images smaller than 1.25 mag. Among the 19 lensed quasars, 3
have quadruple-image configurations, while the remaining 16 show double images.
This lens sample constrains the cosmological constant to be
\Omega_\Lambda=0.84^{+0.06}_{-0.08}(stat.)^{+0.09}_{-0.07}(syst.) assuming a
flat universe, which is in good agreement with other cosmological observations.
We also report the discoveries of 7 binary quasars with separations ranging
from 1.1" to 16.6", which are identified in the course of our lens survey. This
study concludes the construction of our statistical lens sample in the full
SDSS-I data set.Comment: 37 pages, 2 figures and 5 tables, accepted to A
The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey
The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic
data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data
release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median
z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar
spectra, along with the data presented in previous data releases. These spectra
were obtained with the new BOSS spectrograph and were taken between 2009
December and 2011 July. In addition, the stellar parameters pipeline, which
determines radial velocities, surface temperatures, surface gravities, and
metallicities of stars, has been updated and refined with improvements in
temperature estimates for stars with T_eff<5000 K and in metallicity estimates
for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars
presented in DR8, including stars from SDSS-I and II, as well as those observed
as part of the SDSS-III Sloan Extension for Galactic Understanding and
Exploration-2 (SEGUE-2).
The astrometry error introduced in the DR8 imaging catalogs has been
corrected in the DR9 data products. The next data release for SDSS-III will be
in Summer 2013, which will present the first data from the Apache Point
Observatory Galactic Evolution Experiment (APOGEE) along with another year of
data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at
http://www.sdss3.org/dr
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
The Rapid ASKAP Continuum Survey I: Design and First Results
The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be
conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder
(ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will
aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky
visible from the ASKAP site in Western Australia, and will cover the full ASKAP
band of MHz. The RACS images are generally deeper than the existing
NRAO VLA Sky Survey (NVSS) and Sydney University Molonglo Sky Survey (SUMSS)
radio surveys and have better spatial resolution. All RACS survey products will
be public, including radio images (with arcsecond resolution) and
catalogues of about three million source components with spectral index and
polarisation information. In this paper, we present a description of the RACS
survey and the first data release of 903 images covering the sky south of
declination made over a 288 MHz band centred at 887.5 MHz.Comment: 24 pages, 17 figures, 4 tables. For associated data see
https://data.csiro.au/collections/domain/casdaObservation/results/PRAS110%20-%20The%20Rapid%20ASKAP%20Continuu
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MegaMapper is a proposed ground-based experiment to measure Inflation
parameters and Dark Energy from galaxy redshifts at
A Spectroscopic Road Map for Cosmic Frontier: DESI, DESI-II, Stage-5
In this white paper, we present an experimental road map for spectroscopic
experiments beyond DESI. DESI will be a transformative cosmological survey in
the 2020s, mapping 40 million galaxies and quasars and capturing a significant
fraction of the available linear modes up to z=1.2. DESI-II will pilot
observations of galaxies both at much higher densities and extending to higher
redshifts. A Stage-5 experiment would build out those high-density and
high-redshift observations, mapping hundreds of millions of stars and galaxies
in three dimensions, to address the problems of inflation, dark energy, light
relativistic species, and dark matter. These spectroscopic data will also
complement the next generation of weak lensing, line intensity mapping and CMB
experiments and allow them to reach their full potential.Comment: Contribution to Snowmass 202
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