- ID:
- ivo://CDS.VizieR/J/MNRAS/460/1970
- Title:
- Kepler {delta} Sct stars amplitude modulation
- Short Name:
- J/MNRAS/460/1970
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a thorough search for amplitude modulation of pulsation modes in 983 {delta} Sct stars, which have effective temperatures between 6400<T_eff_<10000K in the Kepler Input Catalogue and were continuously observed by the Kepler Space Telescope for 4yr. We demonstrate the diversity in pulsational behaviour observed, in particular non-linearity, which is predicted for {delta} Sct stars. We analyse and discuss examples of {delta} Sct stars with constant amplitudes and phases; those that exhibit amplitude modulation caused by beating of close-frequency pulsation modes; those that exhibit pure amplitude modulation (with no associated phase variation); those that exhibit phase modulation caused by binarity; and those that exhibit amplitude modulation caused by non-linearity. Using models and examples of individual stars, we demonstrate that observations of the changes in amplitude and phase of pulsation modes can be used to distinguish among the different scenarios. We find that 603 {delta} Sct stars (61.3 per cent) exhibit at least one pulsation mode that varies significantly in amplitude over 4yr. Conversely, many {delta} Sct stars have constant pulsation amplitudes so short-length observations can be used to determine precise frequencies, amplitudes and phases for the most coherent and periodic {delta} Sct stars. It is shown that amplitude modulation is not restricted to a small region on the HR diagram, therefore not necessarily dependent on stellar parameters such as T_eff_, logg or [Fe/H]. Our catalogue of 983 {delta} Sct stars will be useful for comparisons to similar stars observed by K2 and TESS, because the length of the 4-yr Kepler data set will not be surpassed for some time.
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402. Kepler Input Catalog
- ID:
- ivo://archive.stsci.edu/kic10
- Title:
- Kepler Input Catalog
- Short Name:
- KIC
- Date:
- 12 Feb 2020 19:43:29
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The KIC, or Kepler Input Catalog, is the primary source of information about objects observed as part of the ground-based Kepler Spectral Classification Program (SCP) in preparation for the selection of Kepler PI and GO targets. The KIC lists objects down to 21st magnitude, but it is not complete to this limit. Light from only about 1/3 of these 14 million objects falls on the Kepler CCD detector. A small number of the KIC objects are calibration objects distributed across the sky.
- ID:
- ivo://archive.stsci.edu/k2
- Title:
- Kepler K2 Data Search Catalog
- Short Name:
- K2
- Date:
- 22 Jul 2020 21:33:57
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. The K2 Data Search Service provides the main catalog for all K2 data.
- ID:
- ivo://archive.stsci.edu/kepler/k2_epic
- Title:
- Kepler K2 Ecliptic Plane Input Catalog
- Short Name:
- K2 EPIC
- Date:
- 12 Feb 2020 19:53:23
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. The K2 Ecliptic Plane Input Catalog is the primary source of information about objects observed as potential targets for the K2 mission, as the Kepler Input Catalog was used for the original Kepler mission.
- ID:
- ivo://CDS.VizieR/J/AJ/142/160
- Title:
- Kepler Mission. II. Eclipsing binaries in DR2
- Short Name:
- J/AJ/142/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Kepler Mission (launched in 2009 March) provides nearly continuous monitoring of ~156000 objects with unprecedented photometric precision. Coincident with the first data release, we presented a catalog of 1879 eclipsing binary systems identified within the 115deg^2^ Kepler field of view (FOV). Here, we provide an updated catalog from paper I (Prsa et al. 2011, Cat. J/AJ/141/83) augmented with the second Kepler data release which increases the baseline nearly fourfold to 125 days. Three hundred and eighty-six new systems have been added, ephemerides and principal parameters have been recomputed. We have removed 42 previously cataloged systems that are now clearly recognized as short-period pulsating variables and another 58 blended systems where we have determined that the Kepler target object is not itself the eclipsing binary. A number of interesting objects are identified. We present several exemplary cases: four eclipsing binaries that exhibit extra (tertiary) eclipse events; and eight systems that show clear eclipse timing variations indicative of the presence of additional bodies bound in the system. We have updated the period and galactic latitude distribution diagrams. With these changes, the total number of identified eclipsing binary systems in the Kepler FOV has increased to 2165, 1.4% of the Kepler target stars.
- ID:
- ivo://archive.stsci.edu/kepler_koi
- Title:
- Kepler Objects of Interest (KOI)
- Short Name:
- KOI CS
- Date:
- 12 Feb 2020 19:51:12
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- Launched in 2009, the Kepler Mission is surveying a region of our galaxy to determine what fraction of stars in our galaxy have planets and measure the size distribution of those exoplanets. Although Kepler completed its primary mission to determine the fraction of stars that have planets in 2013, it is continuing the search, using a more limited survey mode, under the new name K2. KOI is the Kepler Objects of Interest catalog listing observed Kepler targets which are flagged as potentially having exoplanets but may be false positives caused by other types of transient detection. This catalog is produced by the Kepler project and brought to MAST via NExScI.
- ID:
- ivo://archive.stsci.edu/kepler_published_planets
- Title:
- Kepler Published Planets
- Short Name:
- K Pub Planets
- Date:
- 12 Feb 2020 19:41:28
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- "Kepler Published Planets" is a catalog created from NExScI catalogs listing of published exoplanets found using Kepler. All included metadata is from the published paper.
- ID:
- ivo://CDS.VizieR/J/A+A/529/A89
- Title:
- Kepler satellite variability study
- Short Name:
- J/A+A/529/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an automated variability analysis of the Kepler public data measured in the first quarter (Q1) of the mission. In total, about 150000 light curves have been analysed to detect stellar variability, and to identify new members of known variability classes. We also focus on the detection of variables present in eclipsing binary systems, given the important constraints on stellar fundamental parameters they can provide. The methodology we use here is based on the automated variability classification pipeline which was previously developed for and applied successfully to the CoRoT exofield database and to the limited subset of a few thousand Kepler asteroseismology light curves. We use a Fourier decomposition of the light curves to describe their variability behaviour and use the resulting parameters to perform a supervised classification. Several improvements have been made, including a separate extractor method to detect the presence of eclipses when other variability is present in the light curves. We also included two new variability classes compared to previous work: variables showing signs of rotational modulation and of activity. Statistics are given on the number of variables and the number of good candidates per class. A comparison is made with results obtained for the CoRoT exoplanet data. We present some special discoveries, including variable stars in eclipsing binary systems. Many new candidate non-radial pulsators are found, mainly Delta Sct and Gamma Dor stars. We have studied those samples in more detail by using 2MASS colours. The full classification results are made available as an online catalogue.
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/1466
- Title:
- Kepler stars in the NGC 6866 field
- Short Name:
- J/MNRAS/429/1466
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of stars in the field of the open cluster NGC 6866 (age 650Myr) using data from the Kepler Input Catalogue (KIC) and time series photometry from the Kepler data base. We identify 31 {delta} Scuti and 8 {gamma} Doradus pulsating variables as well as 23 red giants with solar-like oscillations. There are 4 eclipsing binaries and 106 stars showing rotational modulation indicative of starspots. We attempted to identify cluster members using their proper motions but found very poor discrimination between members and non-members. The KIC shows a concentration of stars with distance modulus V_0_-M_V_=10.47+/-0.02. We used assumed radial modes in 9 {delta} Sct stars to determine their asteroseismic luminosities and found that the distance modulus falls within three narrow ranges depending on the assignment of overtone number. One of these ranges coincides with the KIC distance modulus. The rotation periods of main-sequence stars are correlated with colour, so that a period-age-mass relation can be derived from open clusters and applied to stars of unknown ages. Surprisingly, we find that the correlation applies not only to cool stars, but extends to A-type stars in the cluster. Finally, we present measurements of solar-like oscillations in red giants, a few of which might be cluster members.
- ID:
- ivo://CDS.VizieR/J/MNRAS/472/1618
- Title:
- Kepler study of starspot lifetimes
- Short Name:
- J/MNRAS/472/1618
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide-field high-precision photometric surveys such as Kepler have produced reams of data suitable for investigating stellar magnetic activity of cooler stars. Starspot activity produces quasi-sinusoidal light curves whose phase and amplitude vary as active regions grow and decay over time. Here we investigate, first, whether there is a correlation between the size of starspots - assumed to be related to the amplitude of the sinusoid - and their decay time-scale and, secondly, whether any such correlation depends on the stellar effective temperature. To determine this, we computed the auto-correlation functions of the light curves of samples of stars from Kepler and fitted them with apodised periodic functions. The light-curve amplitudes, representing spot size, were measured from the root-mean-squared scatter of the normalized light curves. We used a Monte Carlo Markov Chain to measure the periods and decay time-scales of the light curves. The results show a correlation between the decay time of starspots and their inferred size. The decay time also depends strongly on the temperature of the star. Cooler stars have spots that last much longer, in particular for stars with longer rotational periods. This is consistent with current theories of diffusive mechanisms causing starspot decay. We also find that the Sun is not unusually quiet for its spectral type - stars with solar-type rotation periods and temperatures tend to have (comparatively) smaller starspots than stars with mid-G or later spectral types.
