Search Results - "Covey, Kevin R."

A Universal Stellar Initial Mass Function? A Critical Look at Variations by Bastian, Nate, Covey, Kevin R, Meyer, Michael R

“…Whether the stellar initial mass function (IMF) is universal or is instead sensitive to environmental conditions is of critical importance: The IMF influences…”
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Stellar Rotation in the K2 Sample: Evidence for Modified Spin-down by Gordon, Tyler A., Davenport, James R. A., Angus, Ruth, Foreman-Mackey, Daniel, Agol, Eric, Covey, Kevin R., Agüeros, Marcel A., Kipping, David

“…Abstract We analyze light curves of 284,834 unique K2 targets using a Gaussian process model with a quasi-periodic kernel function. By cross-matching K2 stars…”
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IN-SYNC. IV. THE YOUNG STELLAR POPULATION IN THE ORION A MOLECULAR CLOUD by Rio, Nicola Da, Tan, Jonathan C., Covey, Kevin R., Cottaar, Michiel, Foster, Jonathan B., Cullen, Nicholas C., Tobin, John J., Kim, Jinyoung S., Meyer, Michael R., Nidever, David L., Stassun, Keivan G., Chojnowski, S. Drew, Flaherty, Kevin M., Majewski, Steve, Skrutskie, Michael F., Zasowski, Gail, Pan, Kaike

“…ABSTRACT We present the results of the Sloan Digital Sky Survey APOGEE INfrared Spectroscopy of Young Nebulous Clusters program (IN-SYNC) survey of the Orion A…”
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The Galactic Bulge Exploration. III. Calcium Triplet Metallicities for RR Lyrae Stars by Kunder, Andrea, Prudil, Zdenek, Skaggs, Claire, Reggiani, Henrique, Nataf, David M., Hughes, Joanne, Covey, Kevin R., Devine, Kathryn

“…Abstract RR Lyrae stars (RRLs) are excellent tracers of stellar populations for old, metal-poor components in the the Milky Way and the Local Group. Their…”
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IN-SYNC. II. VIRIAL STARS FROM SUBVIRIAL CORES—THE VELOCITY DISPERSION OF EMBEDDED PRE-MAIN-SEQUENCE STARS IN NGC 1333 by Foster, Jonathan B, Cottaar, Michiel, Covey, Kevin R, Arce, Hector G, Meyer, Michael R, Nidever, David L, Stassun, Keivan G, Tan, Jonathan C, Chojnowski, S Drew, Da Rio, Nicola

“…The initial velocity dispersion of newborn stars is a major unconstrained aspect of star formation theory. Using near-infrared spectra obtained with the APOGEE…”
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IN-SYNC. V. Stellar Kinematics and Dynamics in the Orion A Molecular Cloud by Da Rio, Nicola, Tan, Jonathan C., Covey, Kevin R., Cottaar, Michiel, Foster, Jonathan B., Cullen, Nicholas C., Tobin, John, Kim, Jinyoung S., Meyer, Michael R., Nidever, David L., Stassun, Keivan G., Chojnowski, S. Drew, Flaherty, Kevin M., Majewski, Steven R., Skrutskie, Michael F., Zasowski, Gail, Pan, Kaike

“…The kinematics and dynamics of young stellar populations enable us to test theories of star formation. With this aim, we continue our analysis of the…”
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IN-SYNC. VIII. Primordial Disk Frequencies in NGC 1333, IC 348, and the Orion A Molecular Cloud by Yao, Yuhan, Meyer, Michael R., Covey, Kevin R., Tan, Jonathan C., Rio, Nicola Da

“…In this paper, we address two issues related to primordial disk evolution in three clusters (NGC 1333, IC 348, and Orion A) observed by the INfrared Spectra of…”
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The Factory and the Beehive. V. Chromospheric and Coronal Activity and Its Dependence on Rotation in Praesepe and the Hyades by Núñez, Alejandro, Agüeros, Marcel A., Curtis, Jason L., Covey, Kevin R., Douglas, Stephanie T., Chu, Sabine R., DeLaurentiis, Stanislav, Wang, Minzhi (Luna), Drake, Jeremy J.

“…Abstract Low-mass (≲1.2 M ⊙ ) main-sequence stars lose angular momentum over time, leading to a decrease in their magnetic activity. The details of this…”
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The Brown Dwarf Kinematics Project (BDKP). VI. Ultracool Dwarf Radial and Rotational Velocities from SDSS/APOGEE High-resolution Spectroscopy by Hsu, Chih-Chun, Burgasser, Adam J., Theissen, Christopher A., Birky, Jessica L., Aganze, Christian, Gerasimov, Roman, Schmidt, Sarah J., Blake, Cullen H., Covey, Kevin R., Moreno-Hilario, Elizabeth, Gelino, Christopher R., Serna, Javier, Brownstein, Joel R., Cunha, Katia

“…Abstract We present precise measurements of radial (RV) and projected rotational ( v sin i ) velocities of a sample of 258 M6 to L2 dwarfs with multiepoch,…”
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IN-SYNC. III. THE DYNAMICAL STATE OF IC 348-A SUPER-VIRIAL VELOCITY DISPERSION AND A PUZZLING SIGN OF CONVERGENCE by Cottaar, Michiel, Covey, Kevin R., Foster, Jonathan B., Meyer, Michael R., Tan, Jonathan C., Nidever, David L., Chojnowski, S. Drew, Rio, Nicola da, Flaherty, Kevin M., Frinchaboy, Peter M., Majewski, Steve, Skrutskie, Michael F., Wilson, John C., Zasowski, Gail

“…ABSTRACT Most field stars will have encountered the highest stellar density and hence the largest number of interactions in their birth environment. Yet the…”
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RR Lyrae Stars Belonging to the Candidate Globular Cluster Patchick 99 by Butler, Evan, Kunder, Andrea, Prudil, Zdenek, Covey, Kevin R., Ball, Macy, Campos, Carlos, Gollnick, Kaylen, Olivares Carvajal, Julio, Hughes, Joanne, Devine, Kathryn, Johnson, Christian I., Vivas, A. Katherina, Rich, R. Michael, Joyce, Meridith, Simion, Iulia T., Marchetti, Tommaso, Koch-Hansen, Andreas J., Clarkson, William I., Kuss, Rebekah

“…Abstract Patchick 99 is a candidate globular cluster located in the direction of the Galactic bulge, with a proper motion almost identical to the field and…”
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The Milky Way Bulge Extra-tidal Star Survey: BH 261 (AL 3) by Kunder, Andrea, Prudil, Zdenek, Covey, Kevin R., Hughes, Joanne, Joyce, Meridith, Simion, Iulia T., Kuss, Rebekah, Campos, Carlos, Johnson, Christian I., Pilachowski, Catherine A., Larson, Kristen A., Koch-Hansen, Andreas J., Marchetti, Tommaso, Rich, Michael R., Butler, Evan, Clarkson, William I., Rivet, Michael, Devine, Kathryn, Vivas, A. Katherina, Perren, Gabriel I., Soto, Mario, Silva, Erika

“…Abstract The Milky Way Bulge extra-tidal star survey is a spectroscopic survey with the goal of identifying stripped globular cluster stars from inner Galaxy…”
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Pre-main-sequence Brackett Emitters in the APOGEE DR17 Catalog: Line Strengths and Physical Properties of Accretion Columns by Campbell, Hunter, Khilfeh, Elliott, Covey, Kevin R., Kounkel, Marina, Ballantyne, Richard, Corey, Sabrina, Román-Zúñiga, Carlos G., Hernández, Jesús, Martínez, Ezequiel Manzo, Ramírez, Karla Peña, Roman-Lopes, Alexandre, Stassun, Keivan G., Stringfellow, Guy S., Borissova, Jura, Chojnowski, S. Drew, Ramírez-Preciado, Valeria, Kim, Jinyoung Serena, Serna, Javier, Stutz, Amelia M., López-Valdivia, Ricardo, Suárez, Genaro, Ybarra, Jason E., Longa-Peña, Penélope, Fernández-Trincado, José G.

“…Abstract Very young ( t ≲ 10 Myr) stars possess strong magnetic fields that channel ionized gas from the interiors of their circumstellar disks to the surface…”
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Stellar Properties for a Comprehensive Collection of Star-forming Regions in the SDSS APOGEE-2 Survey by Román-Zúñiga, Carlos G., Kounkel, Marina, Hernández, Jesús, Ramírez, Karla Peña, López-Valdivia, Ricardo, Covey, Kevin R., Stutz, Amelia M., Roman-Lopes, Alexandre, Campbell, Hunter, Khilfeh, Elliott, Tapia, Mauricio, Stringfellow, Guy S., Downes, Juan José, Stassun, Keivan G., Minniti, Dante, Bayo, Amelia, Kim, Jinyoung Serena, Suárez, Genaro, Ybarra, Jason E., Fernández-Trincado, José G., Longa-Peña, Penélope, Ramírez-Preciado, Valeria, Serna, Javier, Lane, Richard R., García-Hernández, D. A., Beaton, Rachael L., Bizyaev, Dmitry, Pan, Kaike

“…Abstract The Sloan Digital Sky Survey IV APOGEE-2 primary science goal was to observe red giant stars throughout the Galaxy to study its dynamics, morphology,…”
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Massive Stars in the SDSS-IV/APOGEE SURVEY. I. OB Stars by Roman-Lopes, A., Román-Zúñiga, C., Tapia, Mauricio, Chojnowski, Drew, Gómez Maqueo Chew, Y., García-Hernández, D. A., Borissova, Jura, Minniti, Dante, Covey, Kevin R., Longa-Peña, Penélope, Fernandez-Trincado, J. G., Zamora, Olga, Nitschelm, Christian

“…In this work, we make use of DR14 APOGEE spectroscopic data to study a sample of 92 known OB stars. We developed a near-infrared semi-empirical spectral…”
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METALLICITY AND TEMPERATURE INDICATORS IN M DWARF K-BAND SPECTRA: TESTING NEW AND UPDATED CALIBRATIONS WITH OBSERVATIONS OF 133 SOLAR NEIGHBORHOOD M DWARFS by ROJAS-AYALA, Bárbara, COVEY, Kevin R, MUIRHEAD, Philip S, LLOYD, James P

“…We present K-band spectra for 133 nearby (d < 33 ps) M dwarfs, including 18 M dwarfs with reliable metallicity estimates (as inferred from an FGK type…”
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Rotating Stars from Kepler Observed with Gaia DR2 by Davenport, James R. A., Covey, Kevin R.

“…We have matched the astrometric data from Gaia Data Release 2 to the sample of stars with measured rotation periods from Kepler. Using 30,305 stars with good…”
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The Evolution of Flare Activity with Stellar Age by Davenport, James R. A., Covey, Kevin R., Clarke, Riley W., Boeck, Austin C., Cornet, Jonathan, Hawley, Suzanne L.

“…Using a recent census of flare stars from the Kepler survey, we have explored how flare activity evolves across stellar main-sequence lifetimes. We utilize a…”
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When Do Stalled Stars Resume Spinning Down? Advancing Gyrochronology with Ruprecht 147 by Curtis, Jason Lee, Agüeros, Marcel A., Matt, Sean P., Covey, Kevin R., Douglas, Stephanie T., Angus, Ruth, Saar, Steven H., Cody, Ann Marie, Vanderburg, Andrew, Law, Nicholas M., Kraus, Adam L., Latham, David W., Baranec, Christoph, Riddle, Reed, Ziegler, Carl, Lund, Mikkel N., Torres, Guillermo, Meibom, Søren, Aguirre, Victor Silva, Wright, Jason T.

“…Recent measurements of rotation periods ( ) in the benchmark open clusters Praesepe (670 Myr), NGC 6811 (1 Gyr), and NGC 752 (1.4 Gyr) demonstrate that, after…”
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Placing the Spotted T Tauri Star LkCa 4 on an HR Diagram by Gully-Santiago, Michael A., Herczeg, Gregory J., Czekala, Ian, Somers, Garrett, Grankin, Konstantin, Covey, Kevin R., Donati, J. F., Alencar, Silvia H. P., Hussain, Gaitee A. J., Shappee, Benjamin J., Mace, Gregory N., Lee, Jae-Joon, Holoien, T. W.-S., Jose, Jessy, Liu, Chun-Fan

“…Ages and masses of young stars are often estimated by comparing their luminosities and effective temperatures to pre-main-sequence stellar evolution tracks,…”
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