2,908 research outputs found
Resolving the delta Andromedae spectroscopic binary with direct imaging
We present a direct image of the innermost companion to the red giant delta
Andromedae using the Stellar Double Coronagraph at the Palomar Observatory. We
use a Markov chain Monte Carlo based algorithm to simultaneously reduce the
data and perform astrometry and photometry of the companion. We determine that
the companion is most likely a main-sequence K-type star and is certainly not
the previously hypothesized white dwarf.Comment: ApJ, accepted. 10 pages, 3 figure
Market Response to the Airline, Natural Gas and Trucking Deregulation Acts: An Empirical Analysis
P.R. Chandy is an Associate Professor of Finance at North Texas State University. Wallace N. Davidson is an Associate Professor of Finance at North Texas State University. Michael C. Walker is an Associate Professor and Chairman of the Department of Finance at the University of Cincinnati
Impacts Of Exchange Rate Fluctuations And Government Debt On Economic Performance For A Latin American Country
Applying the autoregressive conditional heteroskedascity (ARCH) model as developed by Professor Robert F. Engle (1982, 2001) and based on a 1970-2002 sample, real GDP was found positively affected by the peso depreciation, the U.S. economy, real M2 money, government spending and the expected inflation rate, and negatively influenced by government debt. The gradual recovery of the U.S. economy is expected to help the Colombian economy. An increase in government spending helps raise real output, but increasing government debt to finance rising budget deficits would reduce national output
Perusing The Headwaters Of Diversity Among University Presidents
Females and minorities are gaining clout in higher education as the numbers of graduates in each of these groups indicate. Diversity among university presidents is a reality. Indications are that the number of women receiving advanced degrees will continue to grow for some time. Low estimates of graduation rates among women and minorities from years ago do not hold. The impacts of this reality in higher education will continue to be felt for some time
Lack of an Association between Autoimmune Pancreatitis and Varicella Zoster Virus
No abstract available
Large-Scale Correlations in the Lyman-alpha Forest at z = 3-4
We present a study of the spatial coherence of the intergalactic medium
toward two pairs of high-redshift quasars with moderate angular separations
observed with Keck/ESI, Q1422+2309A/Q1424+2255 (z_em = 3.63, theta = 39") and
Q1439-0034A/B (z_em = 4.25, theta = 33"). The crosscorrelation of transmitted
flux in the Lyman-alpha forest shows a 5-7 sigma peak at zero velocity lag for
both pairs. This strongly suggests that at least some of the absorbing
structures span the 230-300/h_70 proper kpc transverse separation between
sightlines. We also statistically examine the similarity between paired spectra
as a function of transmitted flux, a measure which may be useful for comparison
with numerical simulations. In investigating the dependence of the correlation
functions on spectral characteristics, we find that photon noise has little
impact for S/N >~ 10 per resolution element. However, the agreement between the
autocorrelation along the line sight and the crosscorrelation between
sightlines, a potential test of cosmological geometry, depends significantly on
instrumental resolution. Finally, we present an inventory of metal lines. These
include a a pair of strong C IV systems at z ~ 3.4 appearing only toward
Q1439B, and a Mg II + Fe II system present toward Q1439 A and B at z = 1.68.Comment: 33 pages, 13 figures, submitted to Ap
The price of white pine stumpage and lumber during the movement of New Hampshire sawmills into and out of production, Station Bulletin, no.480
The Bulletin is a publication of the New Hampshire Agricultural Experiment Station, College of Life Sciences and Agriculture, University of New Hampshire, Durham, New Hampshire
KECK HIRES Spectroscopy of APM 08279+5255
With an optical R-band magnitude of 15.2, the recently discovered z=3.911 BAL
quasar APM 08279+5255 is an exceptionally bright high redshift source. Its
brightness has allowed us to acquire a high signal-to-noise ratio (~100), high
resolution (~6 km/s) spectrum using the HIRES echelle spectrograph on the 10-m
Keck I telescope. Given the quality of the data, these observations provide an
unprecedented view of associated and intervening absorption systems. Here we
announce the availability of this spectrum to the general astronomical
community and present a brief analysis of some of its main features.Comment: 21 pages including 5 figures. Accepted for publication by PAS
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