2,594 research outputs found
Improved Astrometry and Photometry for the Luyten Catalog. I. Bright Stars
We outline the construction of an updated version of the New Luyten
Two-Tenths (NLTT) catalog of high proper motion stars, which will contain
improved astrometry and photometry for the vast majority of the ~59,000 stars
in NLTT. The bright end is constructed by matching NLTT stars to Hipparcos,
Tycho-2, and Starnet; the faint end by matching to USNO-A and 2MASS. In this
first paper, we detail the bright-end matching procedure. We show that for the
majority of stars in his catalog, Luyten measured positions accurate to 1" even
though he recorded his results much more coarsely. However, there is a long
tail of position errors, with one error as large as 11 deg. Proper-motion
errors for the stars with small position errors are 24 mas/yr (1 sigma) but
deteriorate to 34 mas/yr for stars with inferior positions. NLTT is virtually
100% complete for V15 deg, but completeness in this magnitude
range falls to about 75% at the Galactic plane. Incompleteness near the plane
is not uniform, but is rather concentrated in the interval -80<l<20, where the
Milky Way is brightest.Comment: Submitted to ApJ, 28 pages including 7 figure
Improved Astrometry and Photometry for the Luyten Catalog. II. Faint Stars and the Revised Catalog
We complete construction of a catalog containing improved astrometry and new
optical/infrared photometry for the vast majority of NLTT stars lying in the
overlap of regions covered by POSS I and by the second incremental 2MASS
release, approximately 44% of the sky. The epoch 2000 positions are typically
accurate to 130 mas, the proper motions to 5.5 mas/yr, and the V-J colors to
0.25 mag. Relative proper motions of binary components are measured to 3
mas/yr. The false identification rate is ~1% for 11 < V < 18 and substantially
less at brighter magnitudes. These improvements permit the construction of a
reduced proper motion diagram that, for the first time, allows one to classify
NLTT stars into main-sequence (MS) stars, subdwarfs (SDs), and white dwarfs
(WDs). We in turn use this diagram to analyze the properties of both our
catalog and the NLTT catalog on which it is based. In sharp contrast to popular
belief, we find that NLTT incompleteness in the plane is almost completely
concentrated in MS stars, and that SDs and WDs are detected almost uniformly
over the sky DEC > -33 deg. Our catalog will therefore provide a powerful tool
to probe these populations statistically, as well as to reliably identify
individual SDs and WDs.Comment: 16 figures. We will make the revised NLTT publicly available on
acceptance of the paper, or no later than July 18, 200
Classifying Luyten Stars Using An Optical-Infrared Reduced Proper Motion Diagram
We present a V-J reduced proper motion (RPM) diagram for stars in the New
Luyten Two-Tenths (NLTT) catalog. In sharp contrast to the RPM diagram based on
the original NLTT data, this optical-infrared RPM diagram shows distinct tracks
for white dwarfs, subdwarfs, and main-sequence stars. It thereby permits the
identification of white-dwarf and subdwarf candidates that have a high
probability of being genuine.Comment: Accepted ApJL version. 3 figures (2 in color). Table of candidate new
WDs closer than 20 pc is now include
Photometric Selection of QSO Candidates From GALEX Sources
We present a catalog of 36,120 QSO candidates from the Galaxy Evolution
Explorer (GALEX) Release Two (GR2) UV catalog and the USNO-A2.0 optical
catalog. The selection criteria are established using known quasars from the
Sloan Digital Sky Survey (SDSS). The SDSS sample is then used to assign
individual probabilities to our GALEX-USNO candidates. The mean probability is
~50%, and would rise to ~65% if better morphological information than that from
USNO were available to eliminate galaxies. The sample is ~40% complete for
i<=19.1. Candidates are cross-identified in 2MASS, FIRST, SDSS, and XMM-Newton
Slewing Survey (XMMSL1), whenever such counterparts exist. The present catalog
covers the 8000 square degrees of GR2 lying above 25 degrees Galactic latitude,
but can be extended to all 24,000 square degress that satisfy this criterion as
new GALEX data become available.Comment: AASTeX v5.2, 31 pages, 9 figures. Accepted for publication in ApJ.
Extended tables available in the online edition of the journa
Evaluating Datalog via Tree Automata and Cycluits
We investigate parameterizations of both database instances and queries that
make query evaluation fixed-parameter tractable in combined complexity. We show
that clique-frontier-guarded Datalog with stratified negation (CFG-Datalog)
enjoys bilinear-time evaluation on structures of bounded treewidth for programs
of bounded rule size. Such programs capture in particular conjunctive queries
with simplicial decompositions of bounded width, guarded negation fragment
queries of bounded CQ-rank, or two-way regular path queries. Our result is
shown by translating to alternating two-way automata, whose semantics is
defined via cyclic provenance circuits (cycluits) that can be tractably
evaluated.Comment: 56 pages, 63 references. Journal version of "Combined Tractability of
Query Evaluation via Tree Automata and Cycluits (Extended Version)" at
arXiv:1612.04203. Up to the stylesheet, page/environment numbering, and
possible minor publisher-induced changes, this is the exact content of the
journal paper that will appear in Theory of Computing Systems. Update wrt
version 1: latest reviewer feedbac
Chaplain Spiritual Assessment and Its Efficacy for the Palliative Care Team at Roper St. Francis Healthcare: An Interdisciplinary-Phenomenologic Inquiry
A qualitative phenomenological research methodology was designed and implemented to answer the question: what is it that chaplains assessed which is perceived as useful for the Roper St. Francis Palliative Care team? Twelve Palliative Care practitioners, representing diverse specialties, were interviewed and surveyed to answer the research question. Evidence suggested that spiritual care and chaplaincy assessments were perceived as relevant to the Roper St. Francis’ Palliative Care praxis. However, the gathered data indicates that chaplains and Palliative Care practitioners would benefit from a more standardized/consistent spiritual assessment practice. A set of “Teaching Guidelines” and educational “Activities” was created with the goal of training chaplains in the art of doing Palliative Care spiritual assessments based on the research findings. A certified ACPE supervisor was interviewed about the viability and appropriateness of these “Teaching Guidelines” and “Activities.” This professional educator enriched the educative proposal and validated its potential to train staff chaplains as Palliative Care practitioners
S18RS SGFB No. 5 (SROW)
A FINANCE BILL
To Allocate Nine thousand eight hundred twenty dollars and zero cents $9,820.00 from LSU Legislative Contingency to Help Fund LSU Ambassadors to attend the Southern Regional Orientation Workshop (SROW) on March 15-18, 201
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