Search Results - "LAWLER, JAMES E"

IRON-GROUP ABUNDANCES IN THE METAL-POOR MAIN-SEQUENCE TURNOFF STAR HD 84937 by Sneden, Christopher, Cowan, John J., Kobayashi, Chiaki, Pignatari, Marco, Lawler, James E., Den Hartog, Elizabeth A., Wood, Michael P.

“…ABSTRACT We have derived new, very accurate abundances of the Fe-group elements Sc through Zn (Z = 21−30) in the bright main-sequence turnoff star HD 84937…”
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The R-process Alliance: A Nearly Complete R-process Abundance Template Derived from Ultraviolet Spectroscopy of the R-process-enhanced Metal-poor Star HD 222925 by Roederer, Ian U., Lawler, James E., Den Hartog, Elizabeth A., Placco, Vinicius M., Surman, Rebecca, Beers, Timothy C., Ezzeddine, Rana, Frebel, Anna, Hansen, Terese T., Hattori, Kohei, Holmbeck, Erika M., Sakari, Charli M.

“…We present a nearly complete rapid neutron-capture process ( r -process) chemical inventory of the metal-poor ([Fe/H] = −1.46 ± 0.10) r -process-enhanced…”
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Iron-peak Element Abundances in Warm Very Metal-poor Stars by Sneden, Christopher, Boesgaard, Ann Merchant, Cowan, John J., Roederer, Ian U., Den Hartog, Elizabeth A., Lawler, James E.

“…We have derived new detailed abundances of Mg, Ca, and the Fe-group elements Sc through Zn ( Z = 21−30) for 37 main-sequence turnoff very metal-poor stars…”
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Detailed Iron-peak Element Abundances in Three Very Metal-poor Stars by Cowan, John J., Sneden, Christopher, Roederer, Ian U., Lawler, James E., Hartog, Elizabeth A. Den, Sobeck, Jennifer S., Boesgaard, Ann Merchant

“…We have obtained new detailed abundances of the Fe-group elements Sc through Zn ( Z  = 21–30) in three very metal-poor ([Fe/H] ≈ −3) stars: BD+03 o 740, BD−13…”
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Chemical Compositions of Evolved Stars from Near-infrared IGRINS High-resolution Spectra. I. Abundances in Three Red Horizontal Branch Stars by Af ar, Melike, Sneden, Christopher, Wood, Michael P., Lawler, James E., Bozkurt, Zeynep, Topcu, Gamze Böcek, Mace, Gregory N., Kim, Hwihyun, Jaffe, Daniel T.

“…We have derived elemental abundances of three field red horizontal branch stars using high-resolution (R 45,000), high signal-to-noise ratio (S/N 200) H- and…”
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Improved Laboratory Transition Probabilities for Neutral Chromium and Redetermination of the Chromium Abundance for the Sun and Three Stars by Sobeck, Jennifer S, Lawler, James E, Sneden, Christopher

“…Branching fraction measurements from Fourier transform spectra in conjunction with published radiative lifetimes are used to determine transition probabilities…”
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The Extremely Metal-poor, Neutron Capture-rich Star CS 22892-052: A Comprehensive Abundance Analysis by Sneden, Christopher, Cowan, John J, Lawler, James E, Ivans, Inese I, Burles, Scott, Beers, Timothy C, Primas, Francesca, Hill, Vanessa, Truran, James W, Fuller, George M, Pfeiffer, Bernd, Kratz, Karl-Ludwig

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Origin of the heaviest elements: The rapid neutron-capture process by Cowan, John J., Sneden, Christopher, Lawler, James E., Aprahamian, Ani, Wiescher, Michael, Langanke, Karlheinz, Martínez-Pinedo, Gabriel, Thielemann, Friedrich-Karl

“…The production of about half of the heavy elements found in nature is assigned to a specific astrophysical nucleosynthesis process: the rapid neutron-capture…”
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Application of Laboratory Atomic Physics to Some Significant Stellar Chemical Composition Questions by Sneden, Christopher, Lawler, James, Wood, Michael

“…This brief review highlights some current issues in Galactic stellar nucleosynthesis, and some recent laboratory studies by the Wisconsin atomic physics group…”
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Detection of Al ii in the Ultraviolet Spectra of Metal-poor Stars: An Empirical LTE Test of NLTE Aluminum Abundance Calculations by Roederer, Ian U., Lawler, James E.

“…We report the detection of an Al ii line at 2669.155 Å in 11 metal-poor stars, using ultraviolet spectra obtained with the Space Telescope Imaging Spectrograph…”
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DETECTION OF ELEMENTS AT ALL THREE r-PROCESS PEAKS IN THE METAL-POOR STAR HD 160617 by ROEDERER, Ian U, LAWLER, James E

“…We report the first detection of elements at all three r-process peaks in the metal-poor halo star HD 60617. These elements include arsenic and selenium, which…”
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Vanadium Abundance Derivations in 255 Metal-poor Stars by Ou 欧, Xiaowei 筱葳, Roederer, Ian U., Sneden, Christopher, Cowan, John J., Lawler, James E., Shectman, Stephen A., Thompson, Ian B.

“…We present vanadium (V) abundances for 255 metal-poor stars derived from high-resolution optical spectra from the Magellan Inamori Kyocera Echelle spectrograph…”
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Consistent Iron Abundances Derived from Neutral and Singly Ionized Iron Lines in Ultraviolet and Optical Spectra of Six Warm Metal-poor Stars by Roederer, Ian U., Sneden, Christopher, Lawler, James E., Sobeck, Jennifer S., Cowan, John J., Boesgaard, Ann Merchant

“…Neutral Fe lines in metal-poor stars yield conflicting abundances depending on whether and how deviations from local thermodynamic equilibrium (LTE) are…”
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NEW DETECTIONS OF ARSENIC, SELENIUM, AND OTHER HEAVY ELEMENTS IN TWO METAL-POOR STARS by Roederer, Ian U, Schatz, Hendrik, Lawler, James E, Beers, Timothy C, Cowan, John J, FREBEL, ANNA, Ivans, Inese I, Sneden, Christopher, Sobeck, Jennifer S

“…We use the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope to obtain new high-quality spectra covering the 1900 [< or =, slant]…”
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Europium Isotopic Abundances in Very Metal Poor Stars by Sneden, Christopher, Cowan, John J, Lawler, James E, Burles, Scott, Beers, Timothy C, Fuller, George M

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Evidence of Multiple r-Process Sites in the Early Galaxy: New Observations of CS 22892–052 by Sneden, Christopher, Cowan, John J, Ivans, Inese I, Fuller, George M, Burles, Scott, Beers, Timothy C, Lawler, James E

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HUBBLE SPACE TELESCOPE NEAR-ULTRAVIOLET SPECTROSCOPY OF THE BRIGHT CEMP-NO STAR BD+44°493 by PLACCO, VINICIUS M, Beers, Timothy C, Roederer, Ian U, Cowan, John J, FREBEL, ANNA, Filler, Dan, Ivans, Inese I, Lawler, James E, Schatz, Hendrik, Sneden, Christopher, Sobeck, Jennifer S, Aoki, Wako, Smith, Verne V

“…We present an elemental-abundance analysis, in the near-ultraviolet (NUV) spectral range, for the extremely metal-poor star BD+44[degrees]493 a ninth magnitude…”
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Near-Ultraviolet Observations of HD 221170: New Insights into the Nature of r-Process-rich Stars by Ivans, Inese I, Simmerer, Jennifer, Sneden, Christopher, Lawler, James E, Cowan, John J, Gallino, Roberto, Bisterzo, Sara

“…Employing high-resolution spectra obtained with the near-UV-sensitive detector on the Keck I HIRES, supplemented by data obtained with the McDonald Observatory…”
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The Rise of the s-Process in the Galaxy by Simmerer, Jennifer, Sneden, Christopher, Cowan, John J, Collier, Jason, Woolf, Vincent M, Lawler, James E

“…From newly obtained high-resolution, high signal-to-noise ratio spectra the abundances of the elements La and Eu have been determined over the stellar…”
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The spectroscopic foundation of radiative forcing of climate by carbon dioxide by Mlynczak, Martin G., Daniels, Taumi S., Kratz, David P., Feldman, Daniel R., Collins, William D., Mlawer, Eli J., Alvarado, Matthew J., Lawler, James E., Anderson, L. W., Fahey, David W., Hunt, Linda A., Mast, Jeffrey C.

“…The radiative forcing (RF) of carbon dioxide (CO2) is the leading contribution to climate change from anthropogenic activities. Calculating CO2 RF requires…”
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