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198 results on '"Braun, Kaspar"'

152. THE PTF ORION PROJECT: A POSSIBLE PLANET TRANSITING A T-TAURI STAR

Author

van Eyken, Julian C., primary, Ciardi, David R., additional, von Braun, Kaspar, additional, Kane, Stephen R., additional, Plavchan, Peter, additional, Bender, Chad F., additional, Brown, Timothy M., additional, Crepp, Justin R., additional, Fulton, Benjamin J., additional, Howard, Andrew W., additional, Howell, Steve B., additional, Mahadevan, Suvrath, additional, Marcy, Geoffrey W., additional, Shporer, Avi, additional, Szkody, Paula, additional, Akeson, Rachel L., additional, Beichman, Charles A., additional, Boden, Andrew F., additional, Gelino, Dawn M., additional, Hoard, D. W., additional, Ramírez, Solange V., additional, Rebull, Luisa M., additional, Stauffer, John R., additional, Bloom, Joshua S., additional, Cenko, S. Bradley, additional, Kasliwal, Mansi M., additional, Kulkarni, Shrinivas R., additional, Law, Nicholas M., additional, Nugent, Peter E., additional, Ofek, Eran O., additional, Poznanski, Dovi, additional, Quimby, Robert M., additional, Walters, Richard, additional, Grillmair, Carl J., additional, Laher, Russ, additional, Levitan, David B., additional, Sesar, Branimir, additional, and Surace, Jason A., additional

Published
2012
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153. THE HD 192263 SYSTEM: PLANETARY ORBITAL PERIOD AND STELLAR VARIABILITY DISENTANGLED

Author

Dragomir, Diana, primary, Kane, Stephen R., additional, Henry, Gregory W., additional, Ciardi, David R., additional, Fischer, Debra A., additional, Howard, Andrew W., additional, Jensen, Eric L. N., additional, Laughlin, Gregory, additional, Mahadevan, Suvrath, additional, Matthews, Jaymie M., additional, Pilyavsky, Genady, additional, von Braun, Kaspar, additional, Wang, Sharon X., additional, and Wright, Jason T., additional

Published
2012
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154. THE GJ 436 SYSTEM: DIRECTLY DETERMINED ASTROPHYSICAL PARAMETERS OF AN M DWARF AND IMPLICATIONS FOR THE TRANSITING HOT NEPTUNE

Author

von Braun, Kaspar, primary, Boyajian, Tabetha S., additional, Kane, Stephen R., additional, Hebb, Leslie, additional, van Belle, Gerard T., additional, Farrington, Chris, additional, Ciardi, David R., additional, Knutson, Heather A., additional, ten Brummelaar, Theo A., additional, López-Morales, Mercedes, additional, McAlister, Harold A., additional, Schaefer, Gail, additional, Ridgway, Stephen, additional, Collier Cameron, Andrew, additional, Goldfinger, P. J., additional, Turner, Nils H., additional, Sturmann, Laszlo, additional, and Sturmann, Judit, additional

Published
2012
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155. THE DYNAMICAL MASS AND THREE-DIMENSIONAL ORBIT OF HR7672B: A BENCHMARK BROWN DWARF WITH HIGH ECCENTRICITY

Author

Crepp, Justin R., primary, Johnson, John Asher, additional, Fischer, Debra A., additional, Howard, Andrew W., additional, Marcy, Geoffrey W., additional, Wright, Jason T., additional, Isaacson, Howard, additional, Boyajian, Tabetha, additional, von Braun, Kaspar, additional, Hillenbrand, Lynne A., additional, Hinkley, Sasha, additional, Carpenter, John M., additional, and Brewer, John M., additional

Published
2012
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157. STELLAR DIAMETERS AND TEMPERATURES. I. MAIN-SEQUENCE A, F, AND G STARS

Author

Boyajian, Tabetha S., primary, McAlister, Harold A., additional, van Belle, Gerard, additional, Gies, Douglas R., additional, ten Brummelaar, Theo A., additional, von Braun, Kaspar, additional, Farrington, Chris, additional, Goldfinger, P. J., additional, O'Brien, David, additional, Parks, J. Robert, additional, Richardson, Noel D., additional, Ridgway, Stephen, additional, Schaefer, Gail, additional, Sturmann, Laszlo, additional, Sturmann, Judit, additional, Touhami, Yamina, additional, Turner, Nils H., additional, and White, Russel, additional

Published
2012
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158. A SEARCH FOR THE TRANSIT OF HD 168443b: IMPROVED ORBITAL PARAMETERS AND PHOTOMETRY

Author

Pilyavsky, Genady, primary, Mahadevan, Suvrath, additional, Kane, Stephen R., additional, Howard, Andrew W., additional, Ciardi, David R., additional, de Pree, Chris, additional, Dragomir, Diana, additional, Fischer, Debra, additional, Henry, Gregory W., additional, Jensen, Eric L. N., additional, Laughlin, Gregory, additional, Marlowe, Hannah, additional, Rabus, Markus, additional, von Braun, Kaspar, additional, Wright, Jason T., additional, and Wang, Xuesong X., additional

Published
2011
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160. 55 CANCRI: STELLAR ASTROPHYSICAL PARAMETERS, A PLANET IN THE HABITABLE ZONE, AND IMPLICATIONS FOR THE RADIUS OF A TRANSITING SUPER-EARTH

Author

von Braun, Kaspar, primary, Tabetha, S. Boyajian, additional, ten Brummelaar, Theo A., additional, Kane, Stephen R., additional, van Belle, Gerard T., additional, Ciardi, David R., additional, Raymond, Sean N., additional, López-Morales, Mercedes, additional, McAlister, Harold A., additional, Schaefer, Gail, additional, Ridgway, Stephen T., additional, Sturmann, Laszlo, additional, Sturmann, Judit, additional, White, Russel, additional, Turner, Nils H., additional, Farrington, Chris, additional, and Goldfinger, P. J., additional

Published
2011
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161. TERMS PHOTOMETRY OF KNOWN TRANSITING EXOPLANETS

Author

Dragomir, Diana, primary, Kane, Stephen R., additional, Pilyavsky, Genady, additional, Mahadevan, Suvrath, additional, Ciardi, David R., additional, Zachary Gazak, J., additional, Gelino, Dawn M., additional, Payne, Alan, additional, Rabus, Markus, additional, Ramirez, Solange V., additional, von Braun, Kaspar, additional, Wright, Jason T., additional, and Wyatt, Pamela, additional

Published
2011
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162. THE PALOMAR TRANSIENT FACTORY ORION PROJECT: ECLIPSING BINARIES AND YOUNG STELLAR OBJECTS

Author

van Eyken, Julian C., primary, Ciardi, David R., additional, Rebull, Luisa M., additional, Stauffer, John R., additional, Akeson, Rachel L., additional, Beichman, Charles A., additional, Boden, Andrew F., additional, von Braun, Kaspar, additional, Gelino, Dawn M., additional, Hoard, D. W., additional, Howell, Steve B., additional, Kane, Stephen R., additional, Plavchan, Peter, additional, Ramírez, Solange V., additional, Bloom, Joshua S., additional, Cenko, S. Bradley, additional, Kasliwal, Mansi M., additional, Kulkarni, Shrinivas R., additional, Law, Nicholas M., additional, Nugent, Peter E., additional, Ofek, Eran O., additional, Poznanski, Dovi, additional, Quimby, Robert M., additional, Grillmair, Carl J., additional, Laher, Russ, additional, Levitan, David, additional, Mattingly, Sean, additional, and Surace, Jason A., additional

Published
2011
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163. IMPROVED ORBITAL PARAMETERS AND TRANSIT MONITORING FOR HD 156846b

Author

Kane, Stephen R., primary, Howard, Andrew W., additional, Pilyavsky, Genady, additional, Mahadevan, Suvrath, additional, Henry, Gregory W., additional, von Braun, Kaspar, additional, Ciardi, David R., additional, Dragomir, Diana, additional, Fischer, Debra A., additional, Jensen, Eric, additional, Laughlin, Gregory, additional, Ramirez, Solange V., additional, and Wright, Jason T., additional

Published
2011
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165. ASTROPHYSICAL PARAMETERS AND HABITABLE ZONE OF THE EXOPLANET HOSTING STAR GJ 581

Author

von Braun, Kaspar, primary, Boyajian, Tabetha S., additional, Kane, Stephen R., additional, van Belle, Gerard T., additional, Ciardi, David R., additional, López-Morales, Mercedes, additional, McAlister, Harold A., additional, Henry, Todd J., additional, Jao, Wei-Chun, additional, Riedel, Adric R., additional, Subasavage, John P., additional, Schaefer, Gail, additional, ten Brummelaar, Theo A., additional, Ridgway, Stephen, additional, Sturmann, Laszlo, additional, Sturmann, Judit, additional, Mazingue, Jude, additional, Turner, Nils H., additional, Farrington, Chris, additional, Goldfinger, P. J., additional, and Boden, Andrew F., additional

Published
2011
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168. Accurate Coordinates and 2MASS Cross Identifications for (Almost) All Gliese Catalog Star

Author

Stauffer, John, primary, Tanner, Angelle M., additional, Bryden, Geoffrey, additional, Ramirez, Solange, additional, Berriman, Bruce, additional, Ciardi, David R., additional, Kane, Stephen R., additional, Mizusawa, Trisha, additional, Payne, Alan, additional, Plavchan, Peter, additional, von Braun, Kaspar, additional, Wyatt, Pamela, additional, and Kirkpatrick, J. Davy, additional

Published
2010
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173. MULTIWAVELENGTH MONITORING OF THE NARROW-LINE SEYFERT 1 GALAXY ARAKELIAN 564. III. OPTICAL OBSERVATIONS AND THE OPTICAL--UV--X-RAY CONNECTION

Author

Shemmer, O., Romano, P., Bertram, R., Brinkmann, W., Collier, S., Crowley, K. A., Detsis, E., Filippenko, A. V., Gaskell, C. Martin, George, T. A., Gliozzi, M., Hiller, M. E., Jewell, T. L., Kaspi, Shai, Klimek, Elizabeth S., Lannon, M. H., Li, W D, Martini, P., Mathur, Smita, Negoro, H., Netzer, Hagai, Papadakis, Iossif, Papamastorakis, Ioannis, Peterson, Bradley M., Peterson, Bradley W., Pogge, Richard William, Pronik, V. I., Rumstay, Kenneth S., Sergeev, S. G., Stirpe, G. M., Taylor, C. J., Treffers, R. R., Turner, T. J., Uttley, P., Vestergaard, Marianne, von Braun, Kaspar, Wagner, R. M., Zheng, Z., Shemmer, O., Romano, P., Bertram, R., Brinkmann, W., Collier, S., Crowley, K. A., Detsis, E., Filippenko, A. V., Gaskell, C. Martin, George, T. A., Gliozzi, M., Hiller, M. E., Jewell, T. L., Kaspi, Shai, Klimek, Elizabeth S., Lannon, M. H., Li, W D, Martini, P., Mathur, Smita, Negoro, H., Netzer, Hagai, Papadakis, Iossif, Papamastorakis, Ioannis, Peterson, Bradley M., Peterson, Bradley W., Pogge, Richard William, Pronik, V. I., Rumstay, Kenneth S., Sergeev, S. G., Stirpe, G. M., Taylor, C. J., Treffers, R. R., Turner, T. J., Uttley, P., Vestergaard, Marianne, von Braun, Kaspar, Wagner, R. M., and Zheng, Z.

Abstract

We present the results of a 2 yr long optical monitoring program of the narrow-line Seyfert 1 galaxy Ark 564. The majority of this monitoring project was also covered by X-ray observations (RXT E), and for a period of ~50 days, we observed the galaxy in UV (HST) and X-rays (RXTE and ASCA) simultaneously with the ground-based observations. Rapid and large-amplitude variations seen in the X-ray band, on a daily and hourly timescale, were not detected at optical and UV wavelengths, which in turn exhibited much lower variability either on short (1 day) or long (several months) timescales. The only significant optical variations can be described as two 2È4 day events with ~10% flux variations. We detect no significant optical line variations and thus cannot infer a reverberation size for the broad-line region. Similarly, the large X-ray variations seem to vanish when the light curve is smoothed over a period of 30 days. The UV continuum follows the X-rays with a lag of ~0.4 days, and the optical band lags the UV band by ~2 days. No signiÐcant correlation was found between the entire X-ray data set and the optical band. Focusing on a 20 day interval around the strongest optical event we detect a significant X-ray--optical correlation with similar events seen in the UV and X-rays. Our data are consistent with reprocessing models on the grounds of the energy emitted in this single event. However, several large X-ray flares produced no corresponding optical emission.

Published
2001

175. Gattini: a multisite campaign for the measurement of sky brightness in Antarctica

Author

Moore, Anna, primary, Allen, Graham, additional, Aristidi, Eric, additional, Ashley, Michael, additional, Bedding, Tim, additional, Beichman, Chas, additional, Briguglio, Runa, additional, Busso, Maurizio, additional, Candidi, Maurizio, additional, Ciardi, David, additional, Cui, Xiangqun, additional, Cutispoto, Giuseppe, additional, Distefano, Elisa, additional, Espy, Patrick, additional, Everett, Jon, additional, Feng, Longlong, additional, Hu, Jingyao, additional, Jiang, Zhaoji, additional, Kenyon, Suzanne, additional, Kulesa, Craig, additional, Lawrence, Jon, additional, Le Roux, Brice, additional, Leslie, Tim, additional, Li, Yuangshen, additional, Luong-Van, Daniel, additional, Phillips, Andre, additional, Qin, Weijian, additional, Ragazzoni, Roberto, additional, Riddle, Reed, additional, Sabbatini, Lucia, additional, Salinari, Piero, additional, Saunders, Will, additional, Shang, Zhaohui, additional, Stello, Dennis, additional, Storey, John, additional, Sun, Bo, additional, Suntzeff, Nicolas, additional, Taylor, Melinda, additional, Tosti, Gino, additional, Tothill, Nick, additional, Travouillon, Tony, additional, Van Belle, Gerard, additional, Von Braun, Kaspar, additional, Wang, Lifan, additional, Yan, Jun, additional, Yang, Huigen, additional, Yuan, Xiangyan, additional, Zhu, Zhenxi, additional, and Zhou, Xu, additional

Published
2008
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182. EXPLORE/OC: A Search for Planetary Transits in the Field of the Southern Open Cluster NGC 2660.

Author

von Braun, Kaspar, Lee, Brian L., Mallén-Ornelas, Gabriela, Yee, Howard K.C., Seager, Sara, and Gladders, Michael D.

Subjects
*OPEN clusters of stars, *ASTRONOMICAL photometry, *ASTRONOMICAL transits, *ECLIPSES, *STAR observations, *ASTRONOMY
Abstract

We present preliminary photometric results of a monitoring study of the open cluster NGC 2660 as part of the EXPLORE/OC project to find planetary transits in Galactic open clusters. Analyzing a total of 21000 stars (3000 stars with photometry to 1% or better) yielded three light curves with low-amplitude signals like those typically expected for transiting hot Jupiters. Although their eclipses are most likely caused by non-planetary companions, our methods and photometric precision illustrate the potential to detect planetary transits around stars in nearby open clusters. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2004
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183. EXPLORE/OC: A Search for Planetary Transits in the Field of the Southern Open Cluster NGC 6208.

Author

Lee, Brian L., von Braun, Kaspar, Mallén-Ornelas, Gabriella, Yee, H.K.C., Seager, Sara, and Gladders, Michael D.

Subjects
OPEN clusters of stars, ASTRONOMICAL transits, STAR observations, EXTRASOLAR planets, ASTRONOMICAL photometry, ASTRONOMY
Abstract

The EXPLORE Project expanded in 2003 to include a campaign to monitor rich southern open clusters for transits of extrasolar planets (EXPLORE/OC). In May and June 2003, we acquired precise, high-cadence photometry of the second open cluster in our campaign, NGC 6208. Here, we present preliminary results from our I-band survey of over 60000 stars in the field of NGC 6208, around 5000 of which were monitored with photometric precision better than 1%. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2004
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185. Stellar diameters and temperatures - VI. High angular resolution measurements of the transiting exoplanet host stars HD 189733 and HD 209458 and implications for models of cool dwarfs.

Author

Boyajian, Tabetha, von Braun, Kaspar, Feiden, Gregory A., Huber, Daniel, Basu, Sarbani, Demarque, Pierre, Fischer, Debra A., Schaefer, Gail, Mann, Andrew W., White, Timothy R., Maestro, Vicente, Brewer, John, Lamell, C. Brooke, Spada, Federico, LÃpez-Morales, Mercedes, Ireland, Michael, Farrington, Chris, van Belle, Gerard T., Kane, Stephen R., and Jones, Jeremy

Subjects
*STELLAR atmospheres, *EXTRASOLAR planets, *SPECTRUM analysis, *INTERFEROMETRY, *INFRARED radiation
Abstract

We present direct radii measurements of the well-known transiting exoplanet host stars HD 189733 and HD 209458 using the CHARA Array interferometer. We find the limb-darkened angular diameters to be θLD = 0.3848 ± 0.0055 and 0.2254 ± 0.0072 mas for HD 189733 and HD 209458, respectively. HD 189733 and HD 209458 are currently the only two transiting exoplanet systems where detection of the respective planetary companion's orbital motion from high-resolution spectroscopy has revealed absolute masses for both star and planet. We use our new measurements together with the orbital information from radial velocity and photometric time series data, Hipparcos distances, and newly measured bolometric fluxes to determine the stellar effective temperatures (Teff = 4875 ± 43, 6092 ± 103 K), stellar linear radii (R* = 0.805 ± 0.016, 1.203 ± 0.061 R⊙), mean stellar densities (R* = 1.62 ± 0.11, 0.58 ± 0.14 R⊙), planetary radii (Rp = 1.216 ± 0.024, 1.451 ± 0.074 RJup), and mean planetary densities (Rp = 0.605 ± 0.029, 0.196 ± 0.033 RJup) for HD 189733b and HD 209458b, respectively. The stellar parameters for HD 209458, an F9 dwarf, are consistent with indirect estimates derived from spectroscopic and evolutionary modelling. However, we find that models are unable to reproduce the observational results for the K2 dwarf, HD 189733. We show that, for stellar evolutionary models to match the observed stellar properties of HD 189733, adjustments lowering the solar-calibrated mixing-length parameter to αMLT =1.34 need to be employed. [ABSTRACT FROM AUTHOR]

Published
2015
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188. Retrieval of Precise Radial Velocities from High Resolution Near-Infrared Spectra of M Dwarfs

Author

Gao, Peter, Plavchan, Peter, Gagne, Jonathan, Furlan, Elise, Bottom, Michael, Anglada-Escudé, Guillem, White, Russel J., Davison, Cassy, Mills, Sean, Beichman, Charles A., Brinkworth, Carolyn, Johnson, John, David Ciardi, Wallace, J. Kent, Mennesson, Bertrand, Braun, Kaspar, Vasisht, Gautam, Prato, Lisa A., Kane, Stephen R., Tanner, Angelle M., Walp, Bernie, Crawford, Sam, and Lin, Sean

189. Exoplanets, Cool Stars, and Interferometry

Author

Braun, Kaspar, Boyajian, T. S., Kane, S. R., Belle, G. T., Hebb, L., Jones, J., David Ciardi, Raymond, S., Lopez-Morales, M., Knutson, H. A., Ten Brummelaar, T., Farrington, C., Schaefer, G., Chara Group, T., Georgia State University, University System of Georgia (USG), SSE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Center for High Angular Resolution Astronomy (CHARA), and University System of Georgia (USG)-University System of Georgia (USG)

Subjects
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::Instrumentation and Methods for Astrophysics, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

We have been using the CHARA Interferometric Array on Mount Wilson over the course of the last 4 years to directly determine diameters of stars. When coupled with literature photometry, these radii provide stellar effective temperatures, luminosities, and thus habitable zone locations. This presentation reviews recent results of our survey, particularly with respect to the stars that host extrasolar planets around them, and what we have learned about the planets from studying the parent stars.

190. Empirically determined properties of the K-dwarf HD 189733 and implications for evolutionary models of low-mass stars

Author

Boyajian, Tabetha S., Braun, Kaspar, Feiden, Gregory A., Huber, Daniel, Basu, Sarbani, Demarque, Pierre, Fischer, Debra, Schaefer, Gail, White, Timothy, Maestro, Vicente, Brewer, John Michael, Lamell, Brooke, Spada, Federico, Andrew Mann, Lopez-Morales, Mercedes, Ireland, Michael, Farrington, Christopher D., Belle, Gerard, Kane, Stephen R., Jones, Jeremy, Ten Brummelaar, Theo, Ciardi, David R., Mcalister, Harold A., Ridgway, Stephen T., and Goldfinger, Pj

191. Discovery of Two Jovian Planet Candidates Around AU Mic

Author

Plavchan, Peter, Gao, Peter, Jonathan Gagné, Tanner, Angelle M., Furlan, Elise, Brinkworth, Carolyn, Braun, Kaspar, Ciardi, David R., Kane, Stephen R., White, Russel, Johnson, John A., Hall, Ryan, Giddens, Frank, Zilberman, Perri, Huber, Joe, Nishimoto, America, Cancino, Andrew, Weigand, Denise, and Klenke, Christopher

192. Fundamental Parameters of the Two Hall-of-Famers HD 189733 and HD 209458

Author

Braun, Kaspar, Boyajian, Tabetha S., Feiden, Gregory A., Huber, Daniel, Basu, Sarbani, Demarque, Pierre, Fischer, Debra, Schaefer, Gail, White, Timothy, Maestro, Vicente, Brewer, John Michael, Lamell, Brooke, Spada, Federico, Andrew Mann, Lopez-Morales, Mercedes, Ireland, Michael, Farrington, Christopher D., Belle, Gerard, Kane, Stephen R., Jones, Jeremy, Ten Brummelaar, Theo, Ciardi, David R., Mcalister, Harold A., Ridgway, Stephen T., and Goldfinger, Pj

193. Precise Radial Velocity First Light Observations With iSHELL

Author

Cale, Bryson Lee, Plavchan, Peter, Nishimoto, America, Tanner, Angelle M., Jonathan Gagné, Gao, Peter, Furlan, Elise, White, Russel J., Walp, Bernie, Braun, Kaspar, Brinkworth, Carolyn, Johnson, John A., Anglada-Escudé, Guillem, Henry, Todd J., Catanzarite, Joseph, Kane, Stephen R., Beichman, Charles, Ciardi, David R., Wallace, J. Kent, Mennesson, Bertrand, and Vasisht, Gautam

194. Precise Near-Infrared Radial Velocities

Author

Plavchan, Peter, Gao, Peter, Jonathan Gagné, Furlan, Elise, Bottom, Michael, Davison, Cassy, Mills, Sean, Ciardi, David R., Tanner, Angelle M., Beichman, Charles A., Catanzarite, Joseph, Johnson, John, White, Russel J., Anglada-Escudé, Guillem, Henry, Todd J., Braun, Kaspar, Walp, Bernie, and Prato, Lisa A.

195. The GJ 876 System: Fundamental Stellar Parameters and Planets in the Habitable Zone

Author

Braun, Kaspar, Boyajian, T. S., Jones, J., Kane, S. R., Raymond, S. N., Belle, G. T., David Ciardi, Lopez-Morales, M., Ten Brummelaar, T. A., Mcalister, H. A., Schaefer, G., Ridgway, S. R., Sturmann, J., Sturmann, L., Turner, N. H., Farrington, C., Goldfinger, P. J., Georgia State University, University System of Georgia (USG), SSE 2012, Laboratoire d'astrodynamique, d'astrophysique et d'aéronomie de bordeaux (L3AB), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB), Center for High Angular Resolution Astronomy (CHARA), and University System of Georgia (USG)-University System of Georgia (USG)

Subjects
[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::Instrumentation and Methods for Astrophysics, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

International audience; GJ 876 is a nearby M dwarf hosting four currently known extrasolar planets. We use the CHARA interferometric array to determine the stellar angular diameter. Coupled with trigonometric parallax values and literature photometry, we obtain direct estimates of the stellar physical size, surface temperature, luminosity, and location / extent of the system's habitable zone (HZ). We present our measurement results of the GJ 876 stellar astrophysical parameters and the location of the HZ relative to the planetary orbits.

196. THE DISCOVERY OF HD 37605c AND A DISPOSITIVE NULL DETECTION OF TRANSITS OF HD 37605b.

Author

Sharon Xuesong Wang, Wright, Jason T., Cochran, William, Kane, Stephen R., Henry, Gregory W., Payne, Matthew J., Endl, Michael, MacQueen, Phillip J., Valenti, Jeff A., Antoci, Victoria, Dragomir, Diana, Matthews, Jaymie M., Howard, Andrew W., Marcy, Geoffrey W., Isaacson, Howard, Ford, Eric B., Mahadevan, Suvrath, and von Braun, Kaspar

Subjects
RADIAL velocity of stars, RADIAL velocity of galaxies, PLANETARY mass, GAS giants, EPHEMERIDES
Abstract

We report the radial velocity discovery of a second planetary mass companion to the K0 V star HD 37605, which was already known to host an eccentric, P ∼ 55 days Jovian planet, HD 37605b. This second planet, HD 37605c, has a period of ∼7.5 years with a low eccentricity and an Msin i of ∼3.4 MJup. Our discovery was made with the nearly 8 years of radial velocity follow-up at the Hobby-Eberly Telescope and Keck Observatory, including observations made as part of the Transit Ephemeris Refinement and Monitoring Survey effort to provide precise ephemerides to long-period planets for transit follow-up. With a total of 137 radial velocity observations covering almost 8 years, we provide a good orbital solution of the HD 37605 system, and a precise transit ephemeris for HD 37605b. Our dynamic analysis reveals very minimal planet-planet interaction and an insignificant transit time variation. Using the predicted ephemeris, we performed a transit search for HD 37605b with the photometric data taken by the T12 0.8 m Automatic Photoelectric Telescope (APT) and the MOST satellite. Though the APT photometry did not capture the transit window, it characterized the stellar activity of HD 37605, which is consistent of it being an old, inactive star, with a tentative rotation period of 57.67 days. The MOST photometry enabled us to report a dispositive null detection of a non-grazing transit for this planet. Within the predicted transit window, we exclude an edge-on predicted depth of 1.9% at the ≫10σ level, and exclude any transit with an impact parameter b > 0.951 at greater than 5σ. We present the BOOTTRAN package for calculating Keplerian orbital parameter uncertainties via bootstrapping. We made a comparison and found consistency between our orbital fit parameters calculated by the RVLIN package and error bars by BOOTTRAN with those produced by a Bayesian analysis using MCMC. [ABSTRACT FROM AUTHOR]

Published
2012
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198. A search for eclipsing binaries in galactic globular clusters.

Author

von Braun, Kaspar

Subjects
Eclipsing Binaries, Galactic Globular Clusters, Interstellar Medium, Search
Abstract

We report on the discovery and analysis of short-period (0.1 days < P < 5 days), photometrically varying binary stars around and below the main-sequence turnoff of the globular clusters (GCs) NGC 3201, M10, & M12. These eclipsing binaries (EBs) may be used to determine directly the distances to GCs and constrain the Population II stellar main-sequence masses. During our search for binaries, we discovered the signature of differential reddening across the cluster fields which was especially strong for NGC 3201 and M10. We correct for this differential reddening by calculating average EV-I values for stars in small subregions of the field with respect to a fiducial region, which significantly improves the appearance of the GC color-magnitude diagrams (CMDs). The reddening zero point to be added to the differential value is determined by isochrone fitting. The results of our differential dereddening are presented in the form of high-resolution extinction maps. Our search for EBs returned 14 variable stars (11 EBs) in the field of NGC 3201, 3 variables (1 EB) in M10, and 2 EBs in M12. Of these variables, only one EB in NGC 3201 (a blue straggler W Ursa Majoris contact system) is a definite GC-member, based on spectroscopic observations. Another W UMa contact EB in M12 is most likely a member of M12, based on its location in the color-magnitude diagram (CMD) and its empirically calculated absolute magnitude. We present the phased lightcurves for all variables, estimate their distances and GC membership, and show their locations in the GC fields and CMDs, as well as the spectra of the NGC 3201 EBs. Finally, we discuss the implications of our results and outline future work.

Published
2002

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