58,978 research outputs found
A Chat between Cats
This scene is about what goes on during the intermission of Cats the Musical. The scene is full of little conversations between different people one would see attending a musical
Parent Stars of Extrasolar Planets. XI. Trends with Condensation Temperature Revisited
We report the results of abundance analyses of new samples of stars with
planets and stars without detected planets. We employ these data to compare
abundance-condensation temperature trends in both samples. We find that stars
with planets have more negative trends. In addition, the more metal-rich stars
with planets display the most negative trends. These results confirm and extend
the findings of Ramirez et al. (2009) and Melendez et al. (2009), who
restricted their studies to solar analogs. We also show that the differences
between the solar photospheric and CI meteoritic abundances correlate with
condensation temperature.Comment: 7 pages, 11 figures; to be published in MNRA
Parent Stars of Extrasolar Planets. X. Lithium Abundances and vsini Revisited
We determine Li abundances and vsini values from new spectra of 53 stars with
Doppler-detected planets not included in our previous papers in this series. We
also examine two sets of stars without detected planets, which together serve
as our comparison sample. Using the method of comparison of Li abundances and
vsini values between two sets of stars we introduced in Gonzalez (2008), we
confirm that these two quantities are smaller among stars with planets compared
to stars without detected planets near the solar temperature. The transition
from low to high Li abundance among SWPs occurs near 5850 K, a revision of
about 50 K from our previous determination. The transition from low to high
vsini occurs near 6000 K, but this temperature is not as well constrained.Comment: accepted for publication in MNRAS; 14 pages, 13 figures, 3 table
An analysis of atmospheric entry trajectories for manned and unmanned missions to the planet Venus
A unified atmospheric density model is presented for the planet Venus, and this model is compatible with Russian and American data obtained during the 1967 Venus launch opportunity. Trajectory characteristics involved in atmospheric entry are discussed with reference to roll-control modulation and entry corridor. Subsequent to a trajectory-oriented discussion of potential Venus mission characteristics, a parametric analysis of manned and unmanned vehicle entry trajectories into the Venusian atmosphere is presented. A sensitivity analysis with reference to atmospheric density deviations is included to show the dependence of corridor depth on the atmospheric density profile
A Rediscovery of Caddo Heritage: The W. T. Scott Collection at the American Museum of Natural History
Back in August 1997, the Caddo Nation of Oklahoma had submitted a Native American Graves Protection and Repatriation Act (NAGPRA) claim for a cranium that had been obtained by the American Museum of Natural History (AMNH) in New York City in 1877. Very little information was known about these remains, other than it had been obtained as a purchase/gift to the museum by Charles C, Jones Jr. and was found in a mound somewhere near the Shreveport vicinity in Caddo or Bossier Parish, Louisiana. Based on the presence of artificial cranial deformation, the museum dated these human remains to a period of between A.D. 800 and the contact period. Because of the cranial deformation, and the archeological investigations that had taken place in the past in Louisiana, the museum had determined that the remains were culturally affiliated to the Caddo Nation.
Through consultation with the Caddo Nation of Oklahoma and the Cultural Resources Office staff at the AMNH, in February 200 l the Notice of Inventory Completion was published for these human remains in the Federal Register
Estimate of CP Violation for the LBNE Project and $\delta_{CP}
Measurements of CP violation (CPV) and the basic parameter are
the goals of the LBNE Project, which is being planned. Using the expected
energy and baseline parameters for the LBNE Project, CPV and the dependence of
CPV on are estimated, to help in the planning of this project.Comment: 7 pages, 1 figur
Metallicities of M Dwarf Planet Hosts from Spectral Synthesis
We present the first spectroscopic metallicities of three M dwarfs with known
or candidate planetary mass companions. We have analyzed high resolution, high
signal-to-noise spectra of these stars which we obtained at McDonald
Observatory. Our analysis technique is based on spectral synthesis of atomic
and molecular features using recently revised cool-star model atmospheres and
spectrum synthesis code. The technique has been shown to yield results
consistent with the analyses of solar-type stars and allows measurements of M
dwarf [M/H] values to 0.12 dex precision. From our analysis, we find [M/H] =
-0.12, -0.32, and -0.33 for GJ 876, GJ 436, and GJ 581 respectively. These
three M dwarf planet hosts have sub-solar metallicities, a surprising departure
from the trend observed in FGK-type stars. This study is the first part of our
ongoing work to determine the metallicities of the M dwarfs included in the
McDonald Observatory planet search program.Comment: 13 pages, 2 figures, accepted for publication in ApJ
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