VizieR Online Data Catalog: Kepler follow-up observation program. I. Imaging (Furlan+, 2017)
Abstract
We present results from six years of follow-up imaging observations of KOI host stars, including work done by teams from the Kepler Community Follow-up Observation Program (CFOP; https://exofop.ipac.caltech.edu/cfop.php) and by other groups.
Several observing facilities were used to obtain high-resolution images of KOI host stars. Table1 lists the various telescopes, instruments used, filter bandpasses, typical Point Spread Function (PSF) widths, number of targets observed, and main references for the published results. The four main observing techniques employed are adaptive optics (Keck, Palomar, Lick, MMT), speckle interferometry (Gemini North, WIYN, DCT), lucky imaging (Calar Alto), and imaging from space with HST. A total of 3557 KOI host stars were observed at 11 facilities with 9 different instruments, using filters from the optical to the near-infrared. In addition, 10 of these stars were also observed at the 8m Gemini North telescope by Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) using laser guide star adaptive optics. The largest number of KOI host stars (3320) were observed using Robo-AO at the Palomar 1.5m telescope (Baranec et al. 2014ApJ...790L...8B; Baranec et al. 2016, Cat. J/AJ/152/18; Law et al. 2014, Cat. J/ApJ/791/35; Ziegler et al. 2016, AJ accepted, arXiv:1605.03584). A total of 8332 observations were carried out from 2009 September to 2015 October covering 3557 stars. We carried out observations at the Keck, Palomar, and Lick Observatory using the facility adaptive optics systems and near-infrared cameras from 2009 to 2015. At Keck, we observed with the 10m Keck II telescope and Near-Infrared Camera, second generation (NIRC2). The pixel scale of NIRC2 was 0.01''/pixel, resulting in a field of view of about 10''*10''. We observed our targets in a narrow K-band filter, Brγ, which has a central wavelength of 2.1686μm. In most cases, when a companion was detected, we also observed the target in a narrow-band J filter, Jcont, which is centered at 1.2132μm. At Palomar, we used the 5m Hale telescope with the Palomar High Angular Resolution Observer (PHARO). We used the 0.025''/pixel scale, which yielded a field of view of about 25''*25''. As at Keck, we typically used a narrow-band filter in the K-band, Brγ centered at 2.18μm, to observe our targets. When a companion was detected, we usually also observed our targets in the J filter (centered at 1.246μm). At Lick, we used the 3m Shane telescope and the IR Camera for Adaptive Optics at Lick (IRCAL). With its 0.075''/pixel scale, it offered a field of view of about 19''*19''. We observed our targets with the J filter (centered at 1.238μm) or the H filter (centered at 1.656μm). Our team also carried out speckle imaging using the Differential Speckle Survey Instrument (DSSI) at Gemini North, the Wisconsin-Indiana-Yale-NOAO (WIYN) telescope, and at the Discovery Channel Telescope (DCT) from 2010 to 2015. Table5 lists the various observing dates at the three telescopes. At the 8m Gemini North telescope, 158 unique KOI host stars were observed, while at the 3.5m WIYN telescope, 681 stars were targeted. The more recent observing runs at the 4m DCT telescope covered 75 stars. Overall, at all three telescopes, the observations were directed at 828 unique KOI host stars. Targets were observed simultaneously in two bands, centered at 562nm and 692nm (both with a bandwidth of 40nm), or at 692nm and 880nm (the latter with a bandwidth of 50nm). Some targets have data in all three bands. The field of view of the speckle images is smaller than that of the AO images, about 3'' on each side, but the PSF widths are narrower (0.02''-0.05''), resulting in better spatial resolution. Some of the results on DSSI observations of KOIs can be found in Howell et al. 2011 (Cat. J/AJ/142/19), Horch et al. ( 2012AJ....144..165H, 2014ApJ...795...60H), Everett et al. (2015AJ....149...55E), and Teske et al. (2015AJ....150..144T). Wang et al. (2015ApJ...806..248W, 2015ApJ...813..130W) used the adaptive optics systems at Keck and Palomar with NIRC2 and PHARO, respectively, and typically observed each target with the J-, H-, and K-band filters. Adams et al. 2012 (Cat. J/AJ/144/42), Adams et al. (2013AJ....146....9A) and Dressing et al. (2014AJ....148...78D) mainly used the Ks filter in their AO observations at the MMT; in addition, they often used the J-band filter when a companion was detected in the Ks image. The field of view of the ARIES instrument on the MMT was 20''*20'', somewhat smaller than that of PHARO at Palomar, and the FWHM of the stellar images varied between about 0.1'' and 0.6''. Kraus et al. 2016 (Cat. J/AJ/152/8) employed adaptive optics imaging and also non-redundant aperture-mask interferometry at Keck with the NIRC2 instrument; the latter technique is limited only by the diffraction limit of the 10m Keck telescope. They used the K' filter for their observations. Baranec et al. 2016 (Cat. J/AJ/152/18) and Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) observed a sample of KOI host stars at Keck using mostly the K' filter on NIRC2. With the Robo-AO imaging at the Palomar 1.5m telescope, Law et al. 2014 (Cat. J/ApJ/791/35), Baranec et al. 2016 (Cat. J/AJ/152/18), and Ziegler et al. 2016 (AJ accepted, arXiv:1605.03584) covered a total of 3320 KOI host stars. For most observations, they used a long-pass filter whose window starts at 600nm (LP600), which is similar to the Kepler bandpass; they also took data for some stars in the Sloan i-band filter and, more rarely, Sloan r and z filters. The typical FWHM of the observed stellar PSF amounted to 0.12''-0.15''; the images covered a field of view of 44''*44''. Lillo-Box et al. (2012, Cat. J/A+A/546/A10; 2014, Cat. J/A+A/566/A103) used the 2.2m Calar Alto telescope with the AstraLux instrument to obtain diffraction-limited imaging with the lucky imaging technique, typically observing in the i- and z-band filters. This technique involves taking a very large number of short exposures and then combining only those images with the best quality (i.e., with the highest Strehl ratios). The FWHM of the stellar PSF in their 24''*24'' images was typically 0.21'', which is somewhat larger than the value from AO images (~0.15''). HST imaging using WFC3 was carried out in the F555W and F775W bands (Cartier et al. 2015ApJ...804...97C; Gilliland et al. 2015AJ....149...24G). The images spanned a relatively large field of view of 40''*40'', and the typical FWHM of the stellar PSF was 0.08''. One additional facility, the 8m Large Binocular Telescope, was used with LMIRCam to observe 24 KOI host stars in the Ks band, but results have not yet been published and are not available on CFOP. Except for 1 of these 24 stars (which has only one false positive transit signal), all have been observed with one or more other facilities too. The Kepler field was observed at the United Kingdom Infrared Telescope (UKIRT) in 2010 using the UKIRT Wide Field Camera (WFCAM). The images were taken in the J band and have a typical spatial resolution of 0.8''-0.9''. Everett et al. (2012PASP..124..316E) carried out a survey of the Kepler field in 2011 using the NOAO Mosaic-1.1 Wide Field Imager on the WIYN 0.9m telescope. They observed the field in UBV filters; the FWHM of the stellar PSF due to seeing ranged from 1.2'' to 2.5'' in the V-band (with somewhat larger values in the U and B band). The source catalog and the images are available on CFOP. (6 data files).- Publication:
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VizieR Online Data Catalog
- Pub Date:
- July 2017
- DOI:
- 10.26093/cds/vizier.51530071
- Bibcode:
- 2017yCat..51530071F
- Keywords:
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- Stars: double and multiple;
- Planets;
- Photometry: infrared;
- Photometry: HST