================================================================================== A PSF-based approach to Kepler/K2 data. II. Exoplanet candidate in Praeseoe (M 44) Libralato M., Nardiello D., Bedin L. R., Borsato L., Granata V., Malavolta L., Piotto G., Ochner P., Cunial A., Nascimbeni V. (2016, MNRAS) ================================================================================== Keywords: techniques: image processing - techniques: photometric - binaries: general - planetary systems - stars: variables: general - Galaxy: open clusters and associations: individual: NGC 2632 (M 44) Abstract: In this work we keep pushing K2 data to a high photometric precision, close to that of the Kepler main mission, using a point-spread function (PSF)-based, neighbour-subtraction technique, which also overcome the dilution effects in crowded environments. We analyse the open cluster M 44 (NGC 2632), observed during the K2 Campaign 5, and extract light curves of stars imaged on module 14, where most of the cluster lies. We present two candidate exoplanets hosted by cluster members and five by field stars. As a by-product of our investigation, we find 1680 eclipsing binaries and variable stars, 1071 of which are new discoveries. Among them, we report the presence of a heartbeat binary star. Together with this work, we release to the community a catalogue with the variable stars and the candidate exoplanets found, as well as all our raw and detrended light curves. Description: We release: (1) an astro-photometric catalogue of all sources analyzed in our work on K2/Campaign 5/Module 14 channel (merge of the 4 mAICs) (2) the light curves of the objects in the field (3) a catalogue for all variable stars and candidate exoplanets found in M 44 field (4) four stacked images, one for each K2/Campaign 5/Module 14 channel File Summary: ----------------------------------------------------------------------------------------------------------- FileName recl Records Explanations ----------------------------------------------------------------------------------------------------------- ReadMe 107 . This file M44_AIC_TOT.CAT 139 24462 Input catalog (merge of the 4 mAICs described in the paper) LC.??????_4? 201 3620 Light curves in M 44 field from K2/C5 data (2199 files) VARIABLE.TOT.CAT 78 1680 Variable stars and exoplanet candidates in K2/C5/M44 field M44_K2_C5_4?_WCS.fits 0 0 K2 Stacked images (FITS files) ----------------------------------------------------------------------------------------------------------- Byte-by-byte Description of file: M44_AIC_TOT.CAT -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 2- 10 F9.5 deg RA Right ascension (J2000) 14- 22 F9.6 deg DEC Declination (J2000) 25- 32 F8.4 mag Nmag Instrumental "white light" magnitude (1) 36- 43 F8.4 mag Bmag Calibrated B magnitude (1) 47- 54 F8.4 mag Rmag Calibrated R magnitude (1) 58- 65 F8.4 mag Imag Calibrated I magnitude (1) 69- 75 F7.3 mag J_2MASS Calibrated J_2MASS magnitude (2) 79- 85 F7.3 mag H_2MASS Calibrated H_2MASS magnitude (2) 89- 95 F7.3 mag K_2MASS Calibrated K_2MASS magnitude (2) 99-105 F7.2 mas/yr pmra PPMXL mu_alpha cosdelta proper motion (3) 109-115 F7.2 mas/yr pmdec PPMXL mu_delta proper motion (3) 119-126 F8.4 mag Kpmag Instrumental Kepler magnitude (4) 130-134 I5 --- ID ID number of the star 138-139 I2 --- Channel K2 Channel in which the star was imaged (5) -------------------------------------------------------------------------------- (1) The magnitude is set at -99.9999 if missing (2) The magnitude is set at -99.999 if missing (3) The proper motion is set at -999.99 if missing (4) The instrumetal Kepler magnitude is set at -99.9999 if the star was not imaged in any K2/C5/module-14 channel (5) The channel number is set at 0 if the star was not imaged in any K2/C5/module-14 channel Byte-by-byte Description of file: LC.?????? ---------------------------------------------------------------------------------------------------------------------- Bytes Format Units Label Explanations ---------------------------------------------------------------------------------------------------------------------- 5- 21 F18.9 day TIME Average BJD for a given K2 long-cadence reconstructed exposure 25- 36 F12.8 mag M1_det Detrended K2 magnitude obtained with 1-pixel aperture photometry 40- 51 F12.8 mag M1_raw Raw K2 magnitude obtained with 1-pixel aperture photometry 55- 66 F12.8 mag M2_det Detrended K2 magnitude obtained with 1.5-pixel aperture photometry 70- 81 F12.8 mag M2_raw Raw K2 magnitude obtained with 1.5-pixel aperture photometry 85- 96 F12.8 mag M3_det Detrended K2 magnitude obtained with 2-pixel aperture photometry 100-111 F12.8 mag M3_raw Raw K2 magnitude obtained with 2-pixel aperture photometry 115-126 F12.8 mag M4_det Detrended K2 magnitude obtained with 2.5-pixel aperture photometry 130-141 F12.8 mag M4_raw Raw K2 magnitude obtained with 2.5-pixel aperture photometry 145-156 F12.8 mag MPSF_det Detrended K2 magnitude obtained with PSF-fitting photometry 160-171 F12.8 mag MPSF_raw Raw K2 magnitude obtained with PSF-fitting photometry 178-186 F12.4 pxl X x position in the corresponding K2 long-cadence reconstructed exposure (in K2 pixel) 193-201 F12.4 pxl Y y position in the corresponding K2 long-cadence reconstructed exposure (in K2 pixel) ---------------------------------------------------------------------------------------------------------------------- Byte-by-byte Description of file: VARIABLE.TOT.CAT -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 2- 6 I5 --- ID ID number of the star 12- 13 I2 --- Channel K2 Channel in which the star was imaged 20- 26 F7.4 mag Mag_K2 Calibrated median K2 magnitude from the light-curve 32- 42 F11.9 day Period Period (1) 49- 49 I1 --- Clas_K2 Light-curve classification flag (2) 55- 78 A24 --- Notes Notes (3) -------------------------------------------------------------------------------- (1) If Period = 74.82 d, the star could be either irregular/long-period variable or the observed variability is due to a systematic effect (2) 1 = candidate variable 2 = "difficult-interpretation" object 3 = possible blend (3) In "Notes" column we provide the exoplanet-candidate name (if any) and the name of the catalogs in the literature in which the star was already listed. The catalogs are labelled as follows: - 1 = Agueros et al. (2011) - 2 = Bouvier et al. (2001) - 3 = Breger et al. (2012) - 4 = Casewell et al. (2012) - 5 = Delorme et al. (2011) - 6 = Douglas et al. (2014) - 7 = Drake et al. (2014) - 8 = Kovacs et al. (2014) - 9 = Li (2007) - 10 = Liu et al. (2007) - 11 = Malavolta et al. (2016) - 12 = Mermilliod, Mayor, & Udry (2009) - 13 = Pepper et al. (2008) - 14 = Quinn et al. (2012) - 15 = Scholz et al. (2011) - 16 = GCVS - 17 = VSX