Search Results - "Theissen, Christopher"

Parallaxes of Cool Objects with WISE: Filling in for Gaia by Theissen, Christopher A.

“…This paper uses the multi-epoch astrometry from the Wide-field Infrared Survey Explorer (WISE) to demonstrate a method to measure proper motions and…”
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Early Time Spectropolarimetry of the Aspherical Type II Supernova SN 2023ixf by Vasylyev, Sergiy S., Yang, Yi, Filippenko, Alexei V., Patra, Kishore C., Brink, Thomas G., Wang, Lifan, Chornock, Ryan, Margutti, Raffaella, Gates, Elinor L., Burgasser, Adam J., Karpoor, Preethi R., LeBaron, Natalie, Softich, Emma, Theissen, Christopher A., Wiston, Eli, Zheng, WeiKang

“…Abstract We present six epochs of optical spectropolarimetry of the Type II supernova (SN) 2023ixf ranging from ∼2 to 15 days after the explosion. Polarimetry…”
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Discovery of the Exceptionally Short Period Ultracool Dwarf Binary LP 413-53AB by Hsu, Chih-Chun, Burgasser, Adam J., Theissen, Christopher A.

“…Abstract We report the detection of large-amplitude, rapid radial velocity (RV) variations and line-splitting in high-resolution Keck/NIRSPEC spectra of the M9…”
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Assessing the C/O Ratio Formation Diagnostic: A Potential Trend with Companion Mass by Hoch, Kielan K. W., Konopacky, Quinn M., Theissen, Christopher A., Ruffio, Jean-Baptiste, Barman, Travis S., Rickman, Emily L., Perrin, Marshall D., Macintosh, Bruce, Marois, Christian

“…Abstract The carbon-to-oxygen (C/O) ratio in an exoplanet atmosphere has been suggested as a potential diagnostic of planet formation. Now that a number of…”
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The 3D Kinematics of the Orion Nebula Cluster: NIRSPEC-AO Radial Velocities of the Core Population by Theissen, Christopher A., Konopacky, Quinn M., Lu, Jessica R., Kim, Dongwon, Zhang, Stella Y., Hsu, Chih-Chun, Chu, Laurie, Wei, Lingfeng

“…Abstract The kinematics and dynamics of stellar and substellar populations within young, still-forming clusters provide valuable information for constraining…”
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The 3D Kinematics of the Orion Nebula Cluster. II. Mass-dependent Kinematics of the Inner Cluster by Wei, Lingfeng, Theissen, Christopher A., Konopacky, Quinn M., Lu, Jessica R., Hsu, Chih-Chun, Kim, Dongwon

“…Abstract We present the kinematic analysis of 246 stars within 4 ′ from the center of Orion Nebula Cluster (ONC), the closest massive star cluster with active…”
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WARM DUST AROUND COOL STARS: FIELD M DWARFS WITH WISE 12 OR 22 μm EXCESS EMISSION by Theissen, Christopher A, West, Andrew A

“…Using the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) spectroscopic catalog, we searched the WISE AllWISE catalog to investigate the occurrence of warm…”
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Astrometric Accelerations as Dynamical Beacons: A Giant Planet Imaged inside the Debris Disk of the Young Star AF Lep by Franson, Kyle, Bowler, Brendan P., Zhou, Yifan, Pearce, Tim D., Bardalez Gagliuffi, Daniella C., Biddle, Lauren I., Brandt, Timothy D., Crepp, Justin R., Dupuy, Trent J., Faherty, Jacqueline, Jensen-Clem, Rebecca, Morgan, Marvin, Sanghi, Aniket, Theissen, Christopher A., Tran, Quang H., Wolf, Trevor N.

“…Abstract We present the direct-imaging discovery of a giant planet orbiting the young star AF Lep, a 1.2 M ⊙ member of the 24 ± 3 Myr β Pic moving group. AF…”
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The Ultracool SpeXtroscopic Survey. I. Volume-limited Spectroscopic Sample and Luminosity Function of M7−L5 Ultracool Dwarfs by Bardalez Gagliuffi, Daniella C., Burgasser, Adam J., Schmidt, Sarah J., Theissen, Christopher, Gagné, Jonathan, Gillon, Michael, Sahlmann, Johannes, Faherty, Jacqueline K., Gelino, Christopher, Cruz, Kelle L., Skrzypek, Nathalie, Looper, Dagny

“…We present a volume-limited, spectroscopically verified sample of M7−L5 ultracool dwarfs (UCDs) within 25 pc. The sample contains 410 sources, of which 93%…”
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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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Moderate-resolution K-band Spectroscopy of the Substellar Companion VHS 1256 b by Hoch, Kielan K. W., Konopacky, Quinn M., Barman, Travis S., Theissen, Christopher A., Brock, Laci, Perrin, Marshall D., Ruffio, Jean-Baptiste, Macintosh, Bruce, Marois, Christian

“…Abstract We present moderate-resolution ( R ∼ 4000) K -band spectra of the planetary-mass companion VHS 1256 b. The data were taken with the OSIRIS integral…”
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JWST-TST High Contrast: Spectroscopic Characterization of the Benchmark Brown Dwarf HD 19467 B with the NIRSpec Integral Field Spectrograph by Hoch, Kielan K. W., Theissen, Christopher A., Barman, Travis S., Perrin, Marshall D., Ruffio, Jean-Baptiste, Rickman, Emily, Konopacky, Quinn M., Manjavacas, Elena, Balmer, William O., Pueyo, Laurent, Kammerer, Jens, van der Marel, Roeland P., Lewis, Nikole K., Girard, Julien H., Seager, Sara, Clampin, Mark, Mountain, C. Matt

“…Abstract We present the atmospheric characterization of the substellar companion HD 19467 B as part of the pioneering James Webb Space Telescope Guaranteed…”
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Multiple Patchy Cloud Layers in the Planetary-mass Object SIMP 0136+0933 by McCarthy, Allison M., Muirhead, Philip S., Tamburo, Patrick, Vos, Johanna M., Morley, Caroline V., Faherty, Jacqueline, Bardalez Gagliuffi, Daniella C., Agol, Eric, Theissen, Christopher

“…Abstract Multiwavelength photometry of brown dwarfs and planetary-mass objects provides insight into their atmospheres and cloud layers. We present…”
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Beyond the Local Volume. I. Surface Densities of Ultracool Dwarfs in Deep HST/WFC3 Parallel Fields by Aganze, Christian, Burgasser, Adam J., Malkan, Mathew, Theissen, Christopher A., Tejada Arevalo, Roberto A., Hsu, Chih-Chun, Bardalez Gagliuffi, Daniella C., Ryan, Russell E., Holwerda, Benne

“…Abstract Ultracool dwarf stars and brown dwarfs provide a unique probe of large-scale Galactic structure and evolution; however, until recently spectroscopic…”
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89 New Ultracool Dwarf Comoving Companions Identified with the Backyard Worlds: Planet 9 Citizen Science Project by Rothermich, Austin, Faherty, Jacqueline K., Bardalez-Gagliuffi, Daniella, Schneider, Adam C., Kirkpatrick, J. Davy, Meisner, Aaron M., Burgasser, Adam J., Kuchner, Marc, Allers, Katelyn, Gagné, Jonathan, Caselden, Dan, Calamari, Emily, Popinchalk, Mark, Suárez, Genaro, Gerasimov, Roman, Aganze, Christian, Softich, Emma, Hsu, Chin-Chun, Karpoor, Preethi, Theissen, Christopher A., Rees, Jon, Cecilio-Flores-Elie, Rosario, Cushing, Michael C., Marocco, Federico, Casewell, Sarah, Bickle, Thomas P., Hamlet, Les, Allen, Michaela B., Beaulieu, Paul, Colin, Guillaume, Gantier, Jean Marc, Gramaize, Leopold, Jalowiczor, Peter, Kabatnik, Martin, Kiwy, Frank, Martin, David W., Pendrill, Billy, Pumphrey, Ben, Sainio, Arttu, Schumann, Jorg, Stevnbak, Nikolaj, Sun, Guoyou, Tanner, Christopher, Thakur, Vinod, Thevenot, Melina, Wedracki, Zbigniew

“…Abstract We report the identification of 89 new systems containing ultracool dwarf companions to main-sequence stars and white dwarfs, using the citizen…”
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Beyond the Local Volume. II. Population Scaleheights and Ages of Ultracool Dwarfs in Deep HST/WFC3 Parallel Fields by Aganze, Christian, Burgasser, Adam J., Malkan, Mathew, Theissen, Christopher A., Tejada Arevalo, Roberto A., Hsu, Chih-Chun, Bardalez Gagliuffi, Daniella C., Ryan, Russell E., Holwerda, Benne

“…Abstract Ultracool dwarfs (UCDs) represent a significant proportion of stars in the Milky Way, and deep samples of these sources have the potential to…”
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Discovery of a Hypervelocity L Subdwarf at the Star/Brown Dwarf Mass Limit by Burgasser, Adam J., Gerasimov, Roman, Kremer, Kyle, Brooks, Hunter, Alvarado, Efrain, Schneider, Adam C., Meisner, Aaron M., Theissen, Christopher A., Softich, Emma, Karpoor, Preethi, Bickle, Thomas P., Kabatnik, Martin, Rothermich, Austin, Caselden, Dan, Kirkpatrick, J. Davy, Faherty, Jacqueline K., Casewell, Sarah L., Kuchner, Marc J.

“…Abstract We report the discovery of a high-velocity, very low-mass star or brown dwarf whose kinematics suggest it is unbound to the Milky Way. CWISE…”
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RUNAWAY M DWARF CANDIDATES FROM THE SLOAN DIGITAL SKY SURVEY by Favia, Andrej, West, Andrew A., Theissen, Christopher A.

“…ABSTRACT We present a sample of 20 runaway M dwarf candidates (RdMs) within 1 kpc of the Sun whose Galactocentric (GC) velocities exceed 400 km s−1. The…”
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A Wide Planetary Mass Companion Discovered through the Citizen Science Project Backyard Worlds: Planet 9 by Faherty, Jacqueline K., Gagné, Jonathan, Popinchalk, Mark, Vos, Johanna M., Burgasser, Adam J., Schümann, Jörg, Schneider, Adam C., Kirkpatrick, J. Davy, Meisner, Aaron M., Kuchner, Marc J., Bardalez Gagliuffi, Daniella C., Marocco, Federico, Caselden, Dan, Gonzales, Eileen C., Rothermich, Austin, Casewell, Sarah L., Debes, John H., Aganze, Christian, Ayala, Andrew, Hsu, Chih-Chun, Cooper, William J., Smart, R. L., Gerasimov, Roman, Theissen, Christopher A.

“…Abstract Through the Backyard Worlds: Planet 9 citizen science project we discovered a late-type L dwarf co-moving with the young K0 star BD+60 1417 at a…”
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2MASS J11151597+1937266: A Young, Dusty, Isolated, Planetary-mass Object with a Potential Wide Stellar Companion by Theissen, Christopher A., Burgasser, Adam J., Gagliuffi, Daniella C. Bardalez, Hardegree-Ullman, Kevin K., Gagné, Jonathan, Schmidt, Sarah J., West, Andrew A.

“…We present 2MASS J11151597+1937266, a recently identified low-surface-gravity L dwarf, classified as an L2γ based on Sloan Digital Sky Survey optical…”
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