Search Results - "Kirby, Evan N"

THE UNIVERSAL STELLAR MASS-STELLAR METALLICITY RELATION FOR DWARF GALAXIES by Kirby, Evan N, Cohen, Judith G, Guhathakurta, Puragra, Cheng, Lucy, Bullock, James S, Gallazzi, Anna

“…We present spectroscopic metallicities of individual stars in seven gas-rich dwarf irregular galaxies (dIrrs), and we show that dIrrs obey the same…”
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SPECTROSCOPIC CONFIRMATION OF THE DWARF GALAXIES HYDRA II AND PISCES II AND THE GLOBULAR CLUSTER LAEVENS 1 by Kirby, Evan N, Simon, Joshua D, Cohen, Judith G

“…We present Keck/DEIMOS spectroscopy of stars in the recently discovered Milky Way satellites Hydra II, Pisces II, and Laevens 1. We measured a velocity…”
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The dynamics of isolated Local Group galaxies by Kirby, Evan N., Bullock, James S., Boylan-Kolchin, Michael, Kaplinghat, Manoj, Cohen, Judith G.

“…We measured velocities of 862 individual red giant stars in seven isolated dwarf galaxies in the Local Group: NGC 6822, IC 1613, VV 124 (UGC 4879), the Pegasus…”
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THE QUENCHING OF THE ULTRA-FAINT DWARF GALAXIES IN THE REIONIZATION ERA by Brown, Thomas M, Tumlinson, Jason, Geha, Marla, Simon, Joshua D, Vargas, Luis C, Vandenberg, Don A, Kirby, Evan N, Kalirai, Jason S, Avila, Roberto J, Gennaro, Mario, Ferguson, Henry C, Munoz, Ricardo R, Guhathakurta, Puragra, Renzini, Alvio

“…We present new constraints on the star formation histories of six ultra-faint dwarf galaxies: Bootes I, Canes Venatici II, Coma Berenices, Hercules, Leo IV,…”
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Manganese Indicates a Transition from Sub- to Near-Chandrasekhar Type Ia Supernovae in Dwarf Galaxies by de los Reyes, Mithi A. C., Kirby, Evan N., Seitenzahl, Ivo R., Shen, Ken J.

“…Abstract Manganese abundances are sensitive probes of the progenitors of Type Ia supernovae (SNe Ia). In this work, we present a catalog of manganese…”
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Kinematics and Metallicity of the Dwarf Spheroidal Galaxy Andromeda XVIII by Kvasova, Kateryna A., Kirby, Evan N., Beaton, Rachael L.

“…Abstract Andromeda XVIII is an isolated dwarf galaxy 579 kpc away from the nearest large galaxy, M31. It is a candidate “backsplash galaxy” that might have…”
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r-process Abundance Patterns in the Globular Cluster M92 by Kirby, Evan N., Ji, Alexander P., Kovalev, Mikhail

“…Abstract Whereas light-element abundance variations are a hallmark of globular clusters, there is little evidence for variations in neutron-capture elements. A…”
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THE BIZARRE CHEMICAL INVENTORY OF NGC 2419, AN EXTREME OUTER HALO GLOBULAR CLUSTER by COHEN, Judith G, KIRBY, Evan N

“…We present new Keck/HIRES observations of six red giants in the globular cluster (GC) NGC 2419. Although the cluster is among the most distant and most…”
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Evolution of the Stellar Mass-Metallicity Relation. II. Constraints on Galactic Outflows from the Mg Abundances of Quiescent Galaxies by Leethochawalit, Nicha, Kirby, Evan N., Ellis, Richard S., Moran, Sean M., Treu, Tommaso

“…We present the stellar mass-[Fe/H] and mass-[Mg/H] relation of quiescent galaxies in two galaxy clusters at z ∼ 0.39 and z ∼ 0.54. We derive the age, [Fe/H],…”
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Multi-element Abundance Measurements from Medium-resolution Spectra. III. Metallicity Distributions of Milky Way Dwarf Satellite Galaxies by Kirby, Evan N, Lanfranchi, Gustavo A, Simon, Joshua D, Cohen, Judith G, Guhathakurta, Puragra

“…We present metallicity distribution functions (MDFs) for the central regions of eight dwarf satellite galaxies of the Milky Way: Fornax, Leo I and II,…”
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Evidence for Sub-Chandrasekhar Type Ia Supernovae from Stellar Abundances in Dwarf Galaxies by Kirby, Evan N., Xie, Justin L., Guo, Rachel, de los Reyes, Mithi A. C., Bergemann, Maria, Kovalev, Mikhail, Shen, Ken J., Piro, Anthony L., McWilliam, Andrew

“…Abstract There is no consensus on the progenitors of Type Ia supernovae (SNe Ia) despite their importance for cosmology and chemical evolution. We address this…”
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Evolution of the Stellar Mass-Metallicity Relation. I. Galaxies in the z ∼ 0.4 Cluster Cl0024 by Leethochawalit, Nicha, Kirby, Evan N., Moran, Sean M., Ellis, Richard S., Treu, Tommaso

“…We present the stellar mass-stellar metallicity relationship (MZR) in the galaxy cluster Cl0024+1654 at z ∼ 0.4 using full-spectrum stellar population…”
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Simultaneous Constraints on the Star Formation History and Nucleosynthesis of Sculptor dSph by de los Reyes, Mithi A. C., Kirby, Evan N., Ji, Alexander P., Nuñez, Evan H.

“…Abstract We demonstrate that using up to seven stellar abundance ratios can place observational constraints on the star formation histories (SFHs) of Local…”
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A Noninteracting Galactic Black Hole Candidate in a Binary System with a Main-sequence Star by Chakrabarti, Sukanya, Simon, Joshua D., Craig, Peter A., Reggiani, Henrique, Brandt, Timothy D., Guhathakurta, Puragra, Dalba, Paul A., Kirby, Evan N., Chang, Philip, Hey, Daniel R., Savino, Alessandro, Geha, Marla, Thompson, Ian B.

“…Abstract We describe the discovery of a solar neighborhood ( d = 468 pc) binary system with a main-sequence sunlike star and a massive noninteracting black…”
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Evidence of a Non-universal Stellar Initial Mass Function. Insights from HST Optical Imaging of Six Ultra-faint Dwarf Milky Way Satellites by Gennaro, Mario, Tchernyshyov, Kirill, Brown, Thomas M., Geha, Marla, Avila, Roberto J., Guhathakurta, Puragra, Kalirai, Jason S., Kirby, Evan N., Renzini, Alvio, Simon, Joshua D., Tumlinson, Jason, Vargas, Luis C.

“…Abstract Using deep observations obtained with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST) , we demonstrate that the…”
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LITHIUM-RICH GIANTS IN GLOBULAR CLUSTERS by Kirby, Evan N, Guhathakurta, Puragra, Zhang, Andrew J, Hong, Jerry, Guo, Michelle, Guo, Rachel, Cohen, Judith G, Cunha, Katia

“…ABSTRACT Although red giants deplete lithium on their surfaces, some giants are Li-rich. Intermediate-mass asymptotic giant branch (AGB) stars can generate Li…”
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Elemental Abundances in M31: Individual and Coadded Spectroscopic [Fe/H] and [α/Fe] throughout the M31 Halo with SPLASH by Wojno, J. Leigh, Gilbert, Karoline M., Kirby, Evan N., Escala, Ivanna, Guhathakurta, Puragra, Beaton, Rachael L., Kalirai, Jason, Chiba, Masashi, Majewski, Steven R.

“…Abstract We present spectroscopic chemical abundances of red giant branch stars in Andromeda (M31), using medium-resolution ( R ∼ 6000) spectra obtained via…”
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Neutron Star Mergers are the Dominant Source of the r-process in the Early Evolution of Dwarf Galaxies by Duggan, Gina E., Kirby, Evan N., Andrievsky, Serge M., Korotin, Sergey A.

“…There are many candidate sites of the r-process: core-collapse supernovae (CCSNe; including rare magnetorotational core-collapse supernovae), neutron star…”
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Uncovering Extremely Metal-Poor Stars in the Milky Way's Ultrafaint Dwarf Spheroidal Satellite Galaxies by Kirby, Evan N, Simon, Joshua D, Geha, Marla, Guhathakurta, Puragra, Frebel, Anna

“…We present new metallicity measurements for 298 individual red giant branch stars in eight of the least luminous dwarf spheroidal galaxies (dSphs) in the Milky…”
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Multi-element Abundance Measurements from Medium-resolution Spectra. I. The Sculptor Dwarf Spheroidal Galaxy by Kirby, Evan N, Guhathakurta, Puragra, Bolte, Michael, Sneden, Christopher, Geha, Marla C

“…We present measurements of Fe, Mg, Si, Ca, and Ti abundances for 388 radial velocity member stars in the Sculptor dwarf spheroidal galaxy (dSph), a satellite…”
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