bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transiting Planets in the Galactic Bulge from SWEEPS Survey and Implications
Authors: Sahu Kailash C. , Casertano Stefano , Valenti Jeff , Bond Howard E. , Brown Thomas M. , Smith T. Ed , Clarkson Will , Minniti Dante , Zoccali Manuela , Livio Mario , Renzini Alvio , Rich R. M. , Panagia Nino , Lubow Stephen , Brown Timothy , Piskunov Nikolai 
Published: February 2009

AbstractThe SWEEPS (Sagittarius Window Eclipsing Extrasolar Planet Search) program was aimed at detecting planets around stars in the Galactic bulge, not only to determine their physical properties, but also to determine whether the properties of planets found in the solar neighborhood, such as their frequency and the metallicity dependence, also hold for the planets in the Galactic bulge. We used the Hubble Space Telescope to monitor 180,000 F, G, K, and M dwarfs in the Galactic bulge continuously for 7 days in order to look for transiting planets. We discovered 16 candidate transiting extrasolar planets with periods of 0.6 to 4.2 days, including a possible new class of ultra-short period planets (USPPs) with P < 1 day. The facts that (i) the coverage in the monitoring program is continuous, (ii) most of the stars are at a known distance (in the Galctic bulge), (iii) monitoring was carried out in 2 passbands, and (iv) the images have high spatial resolution, were crucial in minimizing and estimating the false positive rates. We estimate that at least 45% of the candidates are genuine planets. Radial velocity observations of the two brightest host stars further support the planetary nature of the transiting companions. These results suggest that the planet frequency in the Galactic bulge is similar to that in the solar neighborhood. They also suggest that higher metallicity favors planet formation even in the Galactic bulge. The USPPs occur only around low-mass stars which may suggest that close-in planets around higher-mass stars are irradiately evaporated, or that planets are able to migrate to and survive in close-in orbits only around such old and low-mass stars.
CoRoT: Description of the Mission and Early Results
Authors: Baglin Annie , Auvergne Michel , Barge Pierre , Deleuil Magali , Michel Eric ,   The CoRoT Exoplanet Science Team
Published: February 2009

AbstractThe CoRoT Mission and its performances in flight are summarised. After more than 500 days in orbit, the early results in the exoplanet finding programme are highlighted. The first 5 planets discovered are compared to the previous population of exoplanets.
The first planets discovered from space with the CoRoT mission
Authors: Barge Pierre ,   the CoRoT Exoplanet Science Team
Published: February 2009

AbstractThe pioneer space mission for photometric planet searches CoRoT continuously monitors about 12,000 stars in each of its fields of view. Thanks to the so-called “alarm mode”, transit candidates can be detected early in the processing of the data and before the end of a run of observation. This specificity offers the possibility of rapidly triggering follow-up operations for the confirmation and characterization of the best transit candidates. We present the first objects discovered in this way: four planets and a transition object between brown dwarf and planet. We describe the organization of the CoRoT Exoplanet Science Team and briefly comment on the set of periodic signals identified by the various detection groups in the first three runs of observation.
Characterizing the Eccentricities of Transiting Extrasolar Planets with Kepler and CoRoT
Authors: Ford Eric B. , Colón Knicole D. 
Published: February 2009

AbstractRadial velocity planet searches have revealed that many giant planets have large eccentricities, in striking contrast with the giant planets in the solar system and prior theories of planet formation. The realization that many giant planets have large eccentricities raises a fundamental question: Do terrestrial-size planets of other stars typically have significantly eccentric orbits or nearly circular orbits like the Earth? While space-based missions such as CoRoT and Kepler will be capable of detecting nearly Earth-sized planets, it will be extremely challenging to measure their eccentricities using radial velocity observations. We review several ways that photometric measurements of transit light curves can constrain the eccentricity of transiting planets. In particular, photometric observations of transit durations can be used to characterize the distribution of orbital eccentricities for various populations of transiting planets (e.g., nearly Earth-sized planets in the habitable zone) without relying on radial velocity measurements. Applying this technique to rocky planets to be found by CoRoT and Kepler will enable constraints on theories for the excitation of eccentricities and tidal dissipation. We also remind observers that several short-period transiting planets are known to have significant eccentricities and caution that assuming they are on a circular orbit can reduce the probability of detecting transits, impact planning for follow-up observations, and adversely affect measurements of the physical parameters of the star and planet.
Radial velocity follow-up for confirmation and characterization of transiting exoplanets
Authors: Bouchy François , Moutou Claire , Queloz Didier ,   the CoRoT Exoplanet Science Team
Published: February 2009

AbstractRadial Velocity follow-up is essential to establish or exclude the planetary nature of a transiting companion as well as to accurately determine its mass. Here we present some elements of an efficient Doppler follow-up strategy, based on high-resolution spectroscopy, devoted to the characterization of transiting candidates. Some aspects and results of the radial velocity follow-up of the CoRoT space mission are presented in order to illustrate the strategy used to deal with the zoo of transiting candidates.
Precision radial velocities of double-lined binary stars and the spectroscopic follow-up of circumbinary transiting planet candidates
Authors: Konacki Maciej 
Published: February 2009

AbstractWe present a new iodine cell based approach that allows one to obtain radial velocities of the components of double-lined spectroscopic binary stars (SB2s) with a precision reaching 5 m/s. Such an RV precision is up to 100 times better than what is currently available in the literature for the SB2s. We discuss the applications of our method to the radial velocity searches for circumbinary planets and spectroscopic follow-up of transiting planet candidates around eclipsing binary stars.
The case for a close-in perturber to GJ 436 b
Authors: Ribas Ignasi , Font-Ribera Andreu , Beaulieu Jean-Philippe , Morales Juan Carlos , García-Melendo Enrique 
Published: February 2009

AbstractThe increasing number of transiting planets raises the possibility of finding changes in their transit time, duration and depth that could be indicative of further planets in the system. Experience from eclipsing binaries indeed shows that such changes may be expected. A first obvious candidate to look for a perturbing planet is GJ 436, which hosts a hot transiting Neptune-mass planet in an eccentric orbit. Ribas et al. (2008) suggested that such eccentricity and a possible change in the orbital inclination might be due to a perturbing small planet in a close-in orbit. A radial velocity signal of a 5 M⊕ planet close to the 2:1 mean-motion resonance seemed to provide the perfect candidate. Recent new radial velocities have deemed such signal spurious. Here we put all the available information in context and we evaluate the possibility of a small perturber to GJ 436 b to explain its eccentricity and possible inclination change. In particular, we discuss the constraints provided by the transit time variation data. We conclude that, given the current data, the close-in perturber scenario still offers a plausible explanation to the observed orbital and physical properties of GJ 436 b.
Precision Radial Velocities in the Near Infrared with TEDI
Authors: Lloyd James P. , Czeszumska Agnieszka , Edelstein Jerry , Erskine David , Feuerstein Michael , Halverson Sam , Marckwordt Mario , Mercer Tony , Muirhead Philip , Schwehr Jackie , Muterspaugh Matthew , Wishnow Ed , Wright Jason 
Published: February 2009

AbstractThe TEDI (TripleSpec - Exoplanet Discovery Instrument) is a dedicated instrument for the near-infrared radial velocity search for planetary companions to low-mass stars with the goal of achieving meters-per-second radial velocity precision. Heretofore, such planet searches have been limited almost entirely to the optical band and to stars that are bright in this band. Consequently, knowledge about planetary companions to the populous but visibly faint low-mass stars is limited. In addition to the opportunity afforded by precision radial velocity searches directly for planets around low mass stars, transits around the smallest M dwarfs offer a chance to detect the smallest possible planets in the habitable zones of the parent stars. As has been the the case with followup of planet candidates detected by the transit method requiring radial velocity confirmation, the capability to undertake efficient precision radial velocity measurements of mid-late M dwarfs will be required. TEDI has been commissioned on the Palomar 200” telescope in December 2007, and is currently in a science verification phase.
Probing the Interiors of Very Hot Jupiters Using Transit Light Curves
Authors: Wolf Aaron S. , Ragozzine Darin 
Published: February 2009

AbstractAccurately understanding the interior structure of extra-solar planets is critical for inferring their formation and evolution and resolving the origin of anomalous planetary radii. The internal density distribution of the planet has a direct effect on the star-planet orbit through the gravitational quadrupole of rotational and tidal bulges, measured by the planetary Love number (k2p, twice the apsidal motion constant). We find that the quadrupole of the planetary tidal bulges dominates the rate of apsidal precession of single very hot Jupiters by more than an order of magnitude over general relativity and the stellar quadrupole. For the shortest-period planets, the planetary interior induces precession of a few degrees per year. By investigating the full photometric signal of apsidal precession, we find that transit timing induces a relatively small signal compared to the changes in transit shapes. With its long baseline of ultra-precise photometry, the future space-basedKeplermission should be able to realistically detect the presence or absence of a core in very hot Jupiters with orbital eccentricities as low ase~ 0.001. We show that the signal due tok2pis not degenerate with other parameters and has a unique signature on the transit light curve. This technique, outlined in more detail in Ragozzine & Wolf 2008 provides the first readily employed method for directly probing the interiors of extra-solar planets.
Induced Kozai Migration and Formation of Close-in Planets in Binaries
Authors: Takeda Genya , Kita Ryosuke , Rasio Frederic A. 
Published: February 2009

AbstractMany recent observational studies have concluded that planetary systems commonly exist in multiple-star systems. At least ~20%, and presumably a larger fraction, of the known extrasolar planetary systems are associated with one or more stellar companions. These stellar companions normally exist at large distances from the planetary systems (typical projected binary separations are 102–104AU) and are often faint (ranging from F to T spectral types). Yet, secular cyclic angular momentum exchange with these distant stellar companions can significantly alter the orbital configuration of the planets around the primaries. One of the most interesting and fairly common outcomes seen in numerical simulations is the opening of a large mutual inclination angle between the planetary orbits, forced by differential nodal precessions caused by the binary companion. The growth of the mutual inclination angle between planetary orbits induces additional large-amplitude eccentricity oscillations of the inner planet due to the quadrupole gravitational perturbation by the outer planet. This eccentricity oscillation may eventually result in the orbital decay of the inner planet through tidal friction, as previously proposed as Kozai migration or Kozai cycles with tidal friction (KCTF). This orbital decay mechanism induced by the binary perturbation and subsequent tidal dissipation may stand as an alternative formation channel for close-in extrasolar planets.
On the Origins of Eccentric Close-in Planets
Authors: Matsumura Soko , Takeda Genya , Rasio Fred A. 
Published: February 2009

AbstractStrong tidal interaction with the central star can circularize the orbits of close-in planets. With the standard tidal quality factorQof our solar system, estimated circularization timescales for close-in extrasolar planets are typically shorter than the age of the host stars. While most extrasolar planets with orbital radiia≲ 0.1 AU indeed have circular orbits, some close-in planets with substantial orbital eccentricities have recently been discovered. This new class of eccentric close-in planets implies that either their tidalQfactor is considerably higher, or circularization is prevented by an external perturbation. Here we constrain the tidalQfactor for transiting extrasolar planets by comparing their circularization times with accurately determined stellar ages. Using estimated secular perturbation timescales, we also provide constraints on the properties of hypothetical second planets exterior to the known eccentric close-in planets.
Emergent Exoplanet Flux: Review of the Spitzer Results
Authors: Deming Drake 
Published: February 2009

AbstractObservations using theSpitzer Space Telescopeprovided the first detections of photons from extrasolar planets.Spitzerobservations are allowing us to infer the temperature structure, composition, and dynamics of exoplanet atmospheres. The Spitzer studies extend from many hot Jupiters to the hot Neptune orbiting GJ436. Here I review the current status ofSpitzersecondary eclipse observations, and summarize the results from the viewpoint of what is robust, what needs more work, and what the observations are telling us about the physical nature of exoplanet atmospheres.
Two Classes of Hot Jupiter Atmospheres
Authors: Fortney Jonathan J. 
Published: February 2009

AbstractWe highlight the potential importance of gaseous TiO and VO opacity on the highly irradiated close-in giant planets. The day-side atmospheres of these planets may naturally fall into two classes that are somewhat analogous to the M- and L-type dwarfs. Those that are warm enough to have appreciable opacity due to TiO and VO gases we term the “pM Class” planets, and those that are cooler, such that Ti and V are predominantly in solid condensates, we term “pL Class” planets. The optical spectra of pL Class planets are dominated by neutral atomic Na and K absorption. We discuss a connection between temperature inversions and large day/night temperature contrasts for the pM Class planets. Around a Sun-like primary, for solar composition, this boundary likely occurs at ~0.04-0.05 AU, but we discuss important uncertainties. The difference in the observed day/night contrast between υ And b (pM Class) and HD 189733b (pL Class) is naturally explained in this scenario.
Characterizing the Atmospheres of Hot Jupiters: From Spectra to Multi-Color Maps
Authors: Knutson Heather A. 
Published: February 2009

AbstractWe present new observations of the emission spectrum of the hot Jupiter TrES-4 designed to test the theory that the presence of temperature inversions in the atmospheres of these planets are correlated with the amount of radiation received by the planet. Our observations reveal that TrES-4 has an emission spectrum similar to that of HD 209458b, which requires the presence of an inversion layer high in the atmosphere and water emission bands in order to explain the observed features, providing additional support for that theory. We also present new observations of the thermal phase curve of HD 189733b at 24 μm, which we combine with our previous observations at 8 μm to examine how circulation in this planet's atmosphere varies as a function of depth. We discuss the relationship between the strength of the day-night circulation on both planets and their other observable properties, in particular their emission spectra.
Thermosphere and exosphere of hot Jupiters
Authors: des Etangs Alain Lecavelier 
Published: February 2009

AbstractHere we describe the observations and the resulting constraints on the upper atmosphere (thermosphere and exosphere) of hot Jupiters. In particular, observations and theoretical modeling of hot-Jupiter evaporation are described. The observations allowed the discovery that the planet orbiting HD209458 has an extended atmosphere of escaping hydrogen and showed the presence of oxygen and carbon at very high altitude. These observations give unique constraints on the escape rate and mechanism in the atmosphere of these planets. The most recent Lyman-alpha HST observations of HD189733b allow for the first time to compare the evaporation from two different planets in different environments. We present models to quantify the escape rate from the measured occultation depths, and an energy diagram to describe the evaporation state of hot Jupiters. Using this diagram, it is shown that few already known planets could be remnants of former giant planets.
Future Observations of Transits and Light Curves from Space
Authors: Beichman Charles A. , Greene Tom , Krist John 
Published: February 2009

AbstractA variety of new observational opportunities have made transit and more generally light curve analysis central to the study of exoplanets. Talks at this IAU 253 Symposium have dramatically highlighted the measurement of the radius, density, atmospheric composition and atmospheric thermal structure, presently for relatively large, hot planets, but soon for smaller planets orbiting further from their host stars. On-going and future space observations will play a key role in the detection and characterization of these planetary systems. After a brief review, I focus on two topics: the need for a sensitive all-sky survey for planets transiting the brightest, closest stars and the follow-up opportunities afforded by the James Webb Space Telescope (JWST).
SuperLupus: A Deep, Long Duration Transit Survey
Authors: Bayliss Daniel D. R. , Sackett Penny D. , Weldrake David T. F. 
Published: February 2009

AbstractSuperLupus is a deep transit survey monitoring a Galactic Plane field in the Southern hemisphere. The project is building on the successful Lupus Survey, and will double the number of images of the field from 1700 to 3400, making it one of the longest duration deep transit surveys. The immediate motivation for this expansion is to search for longer period transiting planets (5-8 days) and smaller radii planets. It will also provide near complete recovery for the shorter period planets (1-3 days). In March, April, and May 2008 we obtained the new images and work is currently in progress reducing these new data.
ASTEP South: An Antarctic Search for Transiting Planets around the celestial South pole
Authors: Crouzet N. , Agabi K. , Blazit A. , Bonhomme S. , Fanteï-Caujolle Y. , Fressin F. , Guillot T. , Schmider F.-X. , Valbousquet F. , Bondoux E. , Challita Z. , Abe L. , Daban J.-B. , Gouvret C. ,   the ASTEP team
Published: February 2009

AbstractASTEP South is the first phase of the ASTEP project that aims to determine the quality of Dome C as a site for future photometric searches for transiting exoplanets and discover extrasolar planets from the Concordia base in Antarctica. ASTEP South consists of a front-illuminated 4k × 4k CCD camera, a 10 cm refractor, and a simple mount in a thermalized enclosure. A double-glass window is used to reduce temperature variations and the associated turbulence on the optical path. The telescope is fixed and observes a 4° × 4° field of view centered on the celestial South pole. With this design, A STEP South is very stable and observes with low and constant airmass, both being important issues for photometric precision. We present the project, we show that enough stars are present in our field of view to allow the detection of one to a few transiting giant planets, and that the photometric precision of the instrument should be a few mmag for stars brighter than magnitude 12 and better than 10 mmag for stars of magnitude 14 or less.
A search for transiting planets in the Galactic Plane
Authors: Miller Veronica R. , Albrow Michael D. 
Published: February 2009

AbstractWe are carrying out a deep survey for transiting extrasolar planets in a 1 square degree field in the Galactic Plane. The images to date were taken using the Wide Field Imager on the ESO 2.2m telescope at La Silla. We present details of the analysis and initial results from the survey.
Searching for Planetary Companions to Ultracool Dwarfs: Planet Hunting in the Near Infrared
Authors: Blake Cullen H. , Charbonneau David , Latham David W. 
Published: February 2009

AbstractOwing to their small masses and radii, Ultracool Dwarfs (UCDs; late-M, L, and T dwarfs) may be excellent targets for planet searches and may afford astronomers the opportunity to detect terrestrial planets in the habitable zone. The precise measurements necessary to detect extrasolar planets orbiting UCDs represent a major challenge. We describe two efforts to obtain precise measurements of UCDs in the Near Infrared (NIR). The first involves the robotic NIR observatory PAIRITEL and efforts to obtain photometric precision sufficient for the detection of terrestrial planets transiting UCDs. The second effort involves precise radial velocity measurements of UCDs in the NIR and a survey undertaken with the NIRSPEC spectrograph on Keck.
KELT: A Wide-Field Survey of Bright Stars for Transiting Planets
Authors: Siverd Robert J. , Pepper Joshua , Stanek Kris , Pogge Richard W. , Gaudi B. Scott , DePoy Darren L. 
Published: February 2009

AbstractThe Kilodegree Extremely Little Telescope (KELT) is a wide-field (26° × 26°) robotic survey telescope currently operating in Sonoita, Arizona. Assembled from commercial and off-the-shelf devices, KELT currently surveys ~40% of the Northern sky with sufficient precision to detect transiting planets around bright (8 < V < 12) stars. In the past several years of operation, over 30,000 science images have been acquired. Planet candidate selection and follow-up are currently underway. A brief overview of past and present survey operations, the data reduction pipeline, and initial results follows below.
Comparing the performance of stellar variability filters for the detection of planetary transits
Authors: Bonomo A. S. , Lanza A. F. 
Published: February 2009

AbstractWe have developed a new method to improve the transit detection of Earth-sized planets in front of solar-like stars by fitting stellar microvariability by means of a spot model. A large Monte Carlo numerical experiment has been designed to test the performance of our approach in comparison with other variability filters and fitting techniques for stars of different magnitudes and planets of different radius and orbital period, as observed by the space missions CoRoT and Kepler. Here we report on the results of this experiment.