- ID:
- ivo://CDS.VizieR/J/AJ/161/36
- Title:
- 117 exoplanets in habitable zone with Kepler DR25
- Short Name:
- J/AJ/161/36
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- We present the occurrence rates for rocky planets in the habitable zones (HZs) of main-sequence dwarf stars based on the Kepler DR25 planet candidate catalog and Gaia-based stellar properties. We provide the first analysis in terms of star-dependent instellation flux, which allows us to track HZ planets. We define {eta}{Earth} as the HZ occurrence of planets with radii between 0.5 and 1.5 R{Earth} orbiting stars with effective temperatures between 4800 and 6300K. We find that {eta}{Earth} for the conservative HZ is between 0.37_-0.21_^+0.48^ (errors reflect 68% credible intervals) and 0.60_-0.36_^+0.90^ planets per star, while the optimistic HZ occurrence is between 0.58_-0.33_^+0.73^ and 0.88_-0.51_^+1.28^ planets per star. These bounds reflect two extreme assumptions about the extrapolation of completeness beyond orbital periods where DR25 completeness data are available. The large uncertainties are due to the small number of detected small HZ planets. We find similar occurrence rates between using Poisson likelihood Bayesian analysis and using Approximate Bayesian Computation. Our results are corrected for catalog completeness and reliability. Both completeness and the planet occurrence rate are dependent on stellar effective temperature. We also present occurrence rates for various stellar populations and planet size ranges. We estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ~6pc away and there are ~4 HZ rocky planets around G and K dwarfs within 10pc of the Sun.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/495/4924
- Title:
- Exoplanets in Southern open clusters
- Short Name:
- J/MNRAS/495/4924
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The scope of the project 'A PSF-based Approach to TESS High Quality data Of Stellar clusters' (PATHOS) is the extraction and analysis of high-precision light curves of stars in stellar clusters and young associations for the identification of candidate exoplanets and variable stars. The cutting-edge tools used in this project allow us to measure the real flux of stars in dense fields, minimizing the effects due to contamination by neighbour sources. We extracted about 200000 light curves of stars in 645 open clusters located in the Southern ecliptic hemisphere and observed by TESS during the first year of its mission. We searched for transiting signals and we found 33 objects of interest, 11 of which are strong candidate exoplanets. Because of the limited SNR, we did not find any Earth or super-Earth. We identified two Neptune-size planets orbiting stars with R*<1.5R_{sun}_, implying a frequency f*=1.3+/-0.95 per cent consistent with the frequency around field stars. The seven Jupiter candidates around stars with R*<1.5R_{sun}_ imply a frequency f*=0.19+/-0.07 per cent, which is smaller than in the field. more complete estimate of the survey completeness and false positive rate is needed to confirm these results. Light curves used in this work will be made available to the astronomical community on the Mikulski Archive for Space Telescope under the project PATHOS.
- ID:
- ivo://CDS.VizieR/J/ApJS/240/16
- Title:
- Exoplanets in the Antarctic sky. I. AST3-II DR1
- Short Name:
- J/ApJS/240/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Located at Dome A, the highest point of the Antarctic plateau, the Chinese Kunlun station is considered to be one of the best ground-based photometric sites because of its extremely cold, dry, and stable atmosphere. A target can be monitored from there for over 40 days without diurnal interruption during a polar winter. This makes Kunlun station a perfect site to search for short- period transiting exoplanets. Since 2008, an observatory has existed at Kunlun station, and three telescopes are working there. Using these telescopes, the AST3 project has been carried out over the last 6yr with a search for transiting exoplanets as one of its key programs (CHinese Exoplanet Searching Program from Antarctica --CHESPA). In the austral winters of 2016 and 2017, a set of target fields in the southern continuous viewing zone (CVZ) of TESS were monitored by the AST3-II telescope. In this paper, we introduce the CHESPA and present the first data release containing photometry of 26,578 bright stars (m_i_<=15). The best photometric precision at the optimum magnitude for the survey is around 2 mmag. To demonstrate the data quality, we also present a catalog of 221 variables with a brightness variation greater than 5mmag from the 2016 data. Among these variables, 179 are newly identified periodic variables not listed in the AAVSO database (https://www.aavso.org/), and 67 are listed in the Candidate Target List. These variables will require careful attention to avoid false-positive signals when searching for transiting exoplanets.
- ID:
- ivo://CDS.VizieR/J/ApJS/240/17
- Title:
- Exoplanets in the Antarctic sky. II. 116 candidates
- Short Name:
- J/ApJS/240/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report first results from the CHinese Exoplanet Searching Program from Antarctica (CHESPA)--a wide-field high-resolution photometric survey for transiting exoplanets carried out using telescopes of the AST3 (Antarctic Survey Telescopes times 3) project. There are now three telescopes (AST3-I, AST3-II, and CSTAR-II) operating at Dome A --the highest point on the Antarctic Plateau-- in a fully automatic and remote mode to exploit the superb observing conditions of the site, and its long and uninterrupted polar nights. The search for transiting exoplanets is one of the key projects for AST3. During the austral winters of 2016 and 2017 we used the AST3-II telescope to survey a set of target fields near the southern ecliptic pole, falling within the continuous viewing zone of the TESS mission. The first data release of the 2016 data, including images, catalogs, and light curves of 26578 bright stars (7.5<=m_i_<=15), was presented in Zhang+ (2018, J/ApJS/240/16). The best precision, as measured by the rms of the light curves at the optimum magnitude of the survey (m_i_=10), is around 2mmag. We detect 222 objects with plausible transit signals from these data, 116 of which are plausible transiting exoplanet candidates according to their stellar properties as given by the TESS Input Catalog, Gaia DR2, and TESS-HERMES spectroscopy. With the first data release from TESS expected in late 2018, this candidate list will be timely for improving the rejection of potential false-positives.
- ID:
- ivo://CDS.VizieR/J/MNRAS/490/3806
- Title:
- Exoplanets & variable stars in 47 Tuc field
- Short Name:
- J/MNRAS/490/3806
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The TESS mission will survey ~85 per cent of the sky, giving us the opportunity of extracting high-precision light curves of millions of stars, including stellar cluster members. In this work, we present our project 'A PSF-based Approach to TESS High quality data Of Stellar clusters' (PATHOS), aimed at searching and characterize candidate exoplanets and variable stars in stellar clusters using our innovative method for the extraction of high-precision light curves of stars located in crowded environments. Our technique of light-curve extraction involves the use of empirical point spread functions (PSFs), an input catalogue and neighbour-subtraction. The PSF-based approach allows us to minimize the dilution effects in crowded environments and to extract high-precision photometry for stars in the faint regime (G>13). For this pilot project, we extracted, corrected, and analysed the light curves of 16641 stars located in a dense region centred on the globular cluster 47 Tuc. We were able to reach the TESS magnitude T~16.5 with a photometric precision of ~1 per cent on the 6.5-h time-scale; in the bright regime we were able to detect transits with depth of ~34 parts per million. We searched for variables and candidate transiting exoplanets. Our pipeline detected one planetary candidate orbiting a main-sequence star in the Galactic field. We analysed the period-luminosity distribution for red-giant stars of 47 Tuc and the eclipsing binaries in the field. Light curves are uploaded on the Mikulski Archive for Space Telescopes under the project PATHOS.
- ID:
- ivo://CDS.VizieR/J/ApJ/646/523
- Title:
- Exoplanet systems with stellar companions
- Short Name:
- J/ApJ/646/523
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a reconnaissance for stellar companions to all 131 radial velocity-detected candidate extrasolar planetary systems known as of 2005 July 1. Common proper-motion companions were investigated using the multi-epoch STScI Digitized Sky Surveys and confirmed by matching the trigonometric parallax distances of the primaries to companion distances estimated photometrically. We also attempt to confirm or refute companions listed in the Washington Double Star Catalog (<I/237>), in the Catalogs of Nearby Stars Series by Gliese and Jahreiss (<V/70>, in Hipparcos results (<I/239>, and in Duquennoy & Mayor's radial velocity survey (1991A&A...248..485D). Our findings indicate that a lower limit of 30 (23%) of the 131 exoplanet systems have stellar companions. We report new stellar companions to HD 38529 and HD 188015 and a new candidate companion to HD 169830. We confirm many previously reported stellar companions, including six stars in five systems, that are recognized for the first time as companions to exoplanet hosts. We have found evidence that 20 entries in the Washington Double Star Catalog are not gravitationally bound companions. At least three (HD 178911, 16 Cyg B, and HD 219449), and possibly five (including HD 41004 and HD 38529), of the exoplanet systems reside in triple-star systems. Three exoplanet systems (GJ 86, HD 41004, and Cep) have potentially close-in stellar companions, with planets at roughly Mercury-Mars distances from the host star and stellar companions at projected separations of 20AU, similar to the SunUranus distance. Finally, two of the exoplanet systems contain white dwarf companions. This comprehensive assessment of exoplanet systems indicates that solar systems are found in a variety of stellar multiplicity environments - singles, binaries, and triples - and that planets survive the post-main-sequence evolution of companion stars.
4377. EXOSAT Bibliography
- ID:
- ivo://nasa.heasarc/exopubs
- Title:
- EXOSAT Bibliography
- Short Name:
- EXOPUBS
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains information about all EXOSAT publications in refereed journals that make use of EXOSAT data. Each entry is unique for every combination of publication and X-ray source. For example, a paper which discusses five X-ray sources will have generated five distinct entries in the database, each referring to a different X-ray source. Unlike EXOLOG, the EXOPUBS database also includes entries for serendipitous sources. In addition to standard database parameters such as source name, coordinates, object class, etc., the EXOPUBS includes the full reference (authors, journal, volume, page, year) and title of each publication. Note the information is not complete after the year 1991. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/exohgls
- Title:
- EXOSAT/CMA High Galactic Latitude Survey
- Short Name:
- EXOSAT/High
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A survey of serendipitous source performed in the very soft X-ray band (0.05-2.0 keV) using the EXOSAT imaging telescopes is presented. The survey covers 783 square degrees of high galactic latitude sky and includes 210 serendipitous sources which define a complete (flux-limited) sample. An extensive program of optical and radio observatories together with cross-correlations with catalogs of known objects lead to the identification of 200 of the 210 detected sources. The 10 remaining objects have been preliminarily classified on the basis of their X-ray to optical flux ratios, thus making the sample essentially fully identified. Twenty-three additional serendipitous sources which did not satisfy the requirements for inclusion in the complete sample were also identified during the optical observations program. The complete sample has been used to study the logN-logS relation and the average spectral slope of AGN. It is found that the logN-logS slope is consistent with that of the Einstein Extended Medium Sensitivity Survey (EMSS) and with the "Euclidean" value of 1.5. The normalization of the logN-logS is a strong function of the assumed spectral slope of AGN. Consistency with the results of the EMSS implies that the average (energy) slope of extragalactic sources in the soft X-ray band is very steep (alpha ~ 1.5). An analysis of the association between AGN detection and Galactic NH also shows that alpha is steep and inconsistent with the canonical value of 0.7. The survey was particularly successful in detecting nearby Galactic soft X-ray emitters and includes a significantly higher percentage of stars than the Einstein EMSS, five White Dwarfs, and three previously unknown AM Her type systems. The sample of sources in this catalog has been selected from the CMA database, which it has been generated using a standard processing on the LE data. The source detection algorithm used a sliding cell method. The size of the search cell is such as to maximize the sensitivity across the field of view. For more information about the LE processing see the documentation in the CMA database. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cmaimage
- Title:
- EXOSAT CMA Images for Each Pointing
- Short Name:
- CMAIMAGE
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the images from two EXOSAT LE telescopes with the channel multiplier array (CMA) detectors in the focal plane. The CMA/telescope combination covers the 0.05-2.5 keV energy range with a field of view of 2 degrees and an on-axis angular resolution of 24 arc seconds (HEW). The detectors had no intrinsic spectral capabilities; however, different filters were used to make broad band measurements. The most commonly used were Thin Lexan (number 7), Aluminum-Parylene (number 6) and Boron (number 8). An image was generated for each filter used during an observation. This Browse table was created in March 1995 and updated in October 2003. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cmascreen
- Title:
- EXOSAT/CMA Sources (Screened for Quality)
- Short Name:
- CMASCREEN
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the results of the sources detected from the two EXOSAT LE telescopes. Each telescope had a channel multiplier array, CMA, detector in the focal plane. The CMA/telescope combination covered the 0.05-2.0 keV energy range with a field of view of 2 degrees and an on-axis angular resolution of 20 arcseconds (HEW). The detectors had no intrinsic spectral capabilities; however, different filters were used to make broad band measurements. The most commonly used were thin Lexan (no. 7), Aluminum-Parylene (no. 6) and Boron (no. 8). An image was generated for each observation using a particular filter. A detection program was used to generate one database entry per source detected above a particular threshold. This catalog contains the list of detected sources, details about those detections, plus the names of the files containing the associated image and lightcurves. Since many objects were observed many times, there are multiple entries per object. The list of detections in this database table has been screened for quality. Only sources with qflag_le >= 3 are present. Please refer to the <a href="/W3Browse/exosat/cma.html">CMA</a> database table for the complete, unscreened list of detections. This database table was created by the HEASARC in August 2020, and it is based on a table created by the HEASARC in 1995 or earlier. The original CMA database table was created at the EXOSAT observatory during the post-operation phase (1986-1990) as part of the pipeline processing. These CMA results are part of the HEASARC data holdings from the start of the HEASARC. This is a service provided by NASA HEASARC .