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Enhancing the social studies: A literature based program for fifth grade
Tides and Water Level Requirements for N.O.S Hydrographic Surveys
The Center for Operational Oceanographic Products and Services (CO-OPS) of the National Ocean Service (NOS) contributes to the NOAA Nautical Charting Program by establishing requirements for, and providing the critical water level data necessary to produce accurate depth measurements. CO-OPS efforts involve six main functional areas: 1) tide and water level requirement planning; 2) preliminary tidal zoning development; 3) water level station installation, operation and removal; 4) data quality control, processing, and tabulation; 5) tidal datum computation and tidal datum recovery; and 6) generation of water level reducers and final tidal zoning. For each functional area, CO-OPS maintains appropriate specifications and standard operating procedures under the umbrella of an overall Data Quality Assurance Plan (DQAP). The objective of this effort is to provide the tide and water level correction information necessary to reduce soundings to Chart Datum. The goal is to provide water level correction information that meets current error budgets for correctors to soundings. The total uncertainty in the water level corrections are derived from three main sources: 1) errors in the actual measurement of water level; 2) uncertainties in the computation of tidal datums based on short period observations and in the datum recovery process at historical locations; and 3) uncertainties in the application of tidal zoning within the survey area. CO-OPS plans tide and water level requirements by balancing these uncertainties to provide the most effective combination of water level observations and zoning that meets allowable error budgets
AAT/WFI observations of the Extragalactic H I Cloud HIPASS J1712-64
AAT/WFI optical images of a candidate extragalactic HI cloud, HIPASS
J1712-64, are presented. The g and r-band CCD mosaic camera frames were
processed using a new data pipeline recently installed at the AAO. The
resultant stacked images reach significantly deeper levels than those of
previous published optical imaging of this candidate, providing a detection
limit M_g -7 at a distance of 3Mpc, the inferred distance to HIPASS J1712-64.
However, detailed analysis of the images fails to uncover any stellar
population associated with the HI emission. If this system is a member of the
Local Group then it is pathologically different to other members. Hence, our
observations reinforce earlier suggestions that this HI cloud is most likely
Galactic in origin and not a Local Volume dwarf galaxy.Comment: 8 pages, accepted for publication in PASA (Figures reduced in
resolution, please contact gfl if you wish the higher resolution versions
Galactic Wind Signatures around High Redshift Galaxies
We carry out cosmological chemodynamical simulations with different strengths
of supernova (SN) feedback and study how galactic winds from star-forming
galaxies affect the features of hydrogen (HI) and metal (CIV and OVI)
absorption systems in the intergalactic medium at high redshift. We find that
the outflows tend to escape to low density regions, and hardly affect the dense
filaments visible in HI absorption. As a result, the strength of HI absorption
near galaxies is not reduced by galactic winds, but even slightly increases. We
also find that a lack of HI absorption for lines of sight (LOS) close to
galaxies, as found by Adelberger et al., can be created by hot gas around the
galaxies induced by accretion shock heating. In contrast to HI, metal
absorption systems are sensitive to the presence of winds. The models without
feedback can produce the strong CIV and OVI absorption lines in LOS within 50
kpc from galaxies, while strong SN feedback is capable of creating strong CIV
and OVI lines out to about twice that distance. We also analyze the mean
transmissivity of HI, CIV, and OVI within 1 h Mpc from star-forming
galaxies. The probability distribution of the transmissivity of HI is
independent of the strength of SN feedback, but strong feedback produces LOS
with lower transmissivity of metal lines. Additionally, strong feedback can
produce strong OVI lines even in cases where HI absorption is weak. We conclude
that OVI is probably the best tracer for galactic winds at high redshift.Comment: 16 pages, 16 figures, ApJ in press. Higher resolution version
available at http://www.ociw.edu/~dkawata/research/papers.htm
Developing Leadership for Creative Efforts: A Preface
Michael D. Mumford is the George Lynn Cross distinguished research professor of psychology at the University of Oklahoma where he directs the Center for Applied Social Research. He received his doctoral degree from the University of Georgia in 1983 in the fields of industrial and organizational psychology and psychometrics. He is a fellow of the American Psychological Association (Divisions 3, 5, 10, 14), the Society for Industrial and Organizational Psychology, and the American Psychological Society. He has written more than 270 articles on leadership, creativity, innovation, planning, and ethics. He has served as senior editor of The Leadership Quarterly, and he sits on the editorial boards of the Creativity Research Journal, The Journal of Creative Behavior, IEEE Transactions on Engineering Management, and Ethics and Behavior, among other journals. He has served as principal investor on grants totaling more than US$30 million from the National Science Foundation, The National Institute of Health, the Department of Defense, the Department of Labor, and the Department of State. He is a recipient of the Society for Industrial and Organizational Psychology’s M. Scott Myers Award for Applied Research in the Workplace.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
On Iron Enrichment, Star Formation, and Type Ia Supernovae in Galaxy Clusters
The nature of star formation and Type Ia supernovae (SNIa) in galaxies in the
field and in rich galaxy clusters are contrasted by juxtaposing the build-up of
heavy metals in the universe inferred from observed star formation and
supernovae rate histories with data on the evolution of Fe abundances in the
intracluster medium (ICM). Models for the chemical evolution of Fe in these
environments are constructed, subject to observational constraints, for this
purpose. While models with a mean delay for SNIa of 3 Gyr and standard initial
mass function (IMF) are consistent with observations in the field, cluster Fe
enrichment immediately tracks a rapid, top-heavy phase of star formation --
although transport of Fe into the ICM may be more prolonged and star formation
likely continues to redshifts <1. The source of this prompt enrichment is Type
II supernovae (SNII) yielding at least 0.1 solar masses per explosion (if the
SNIa rate normalization is scaled down from its value in the field according to
the relative number of candidate progenitor stars in the 3-8 solar mass range)
and/or SNIa explosions with short delay times associated with the rapid star
formation mode. Star formation is >3 times more efficient in rich clusters than
in the field, mitigating the overcooling problem in numerical cluster
simulations. Both the fraction of baryons cycled through stars, and the
fraction of the total present-day stellar mass in the form of stellar remnants,
are substantially greater in clusters than in the field.Comment: 51 pages including 26 figures and 2 tables, accepted for publication
in ApJ 5/4/0
The Metallicity of Pre-Galactic Globular Clusters: Observational consequences of the first stars
We explore a scenario where metal-poor globular clusters (GCs) are enriched
by the first supernovae in the Universe. If the first stars in a 10^7 Msun dark
halo were very massive (>180 Msun), then a pair instability supernova from a
single massive star can produce sufficient iron to enrich 10^6 Msun of
pristine, primordial gas to [Fe/H] ~ -2. In such a scenario, where a single
massive star acts as a seed for halo GCs, the accurate abundance analysis of GC
stars would allow a direct measurement of the Population III initial mass.
Using the latest theoretical yields for zero metallicity stars in the mass
range 140-260 Msun, we find that the metals expelled from a ~230 Msun star are
consistent with [Si/Fe] and [Ca/Fe] observed in GC stars. However, no single
star in this mass range can simultaneously explain all halo GC heavy-element
abundance ratios, such as [V/Fe], [Ti/Fe] and [Ni/Fe]. These require a
combination masses for the Population III stellar progenitors. The various
observational consequences of this scenario are discussed.Comment: 5 pages, 2 figures, accepted for publication in ApJ Lette
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