J/AJ/154/124 M dwarfs-long-term photometric variability (Clements+, 2017) ================================================================================ The solar neighborhood. XLI. A study of the wide main sequence for M dwarfs-long-term photometric variability. Clements T.D., Henry T.J., Hosey A.D., Jao W.-C., Silverstein M.L., Winters J.G., Dieterich S.B., Riedel A.R. =2017AJ....154..124C (SIMBAD/NED BibCode) ================================================================================ ADC_Keywords: Stars, nearby ; Stars, dwarfs ; Stars, M-type ; Photometry, VRI ; Photometry, infrared ; Stars, distances Keywords: stars: activity - stars: low-mass Abstract: We report findings from a long-term photometric variability study of M dwarfs carried out at the SMARTS 0.9 m telescope at the Cerro Tololo Inter-American Observatory. As part of a multi-faceted effort to investigate the range of luminosities of M dwarfs of a given color on the Hertzsprung-Russell Diagram, 76 M dwarfs have been observed for 3-17 years in the Johnson-Kron-Cousins V band. We find that stars elevated above the center of the main sequence distribution tend to have higher levels of variability, likely caused by magnetic activity, than their fainter counterparts below the center. This study provides insight into how the long-term magnetic activity of these stars may be affecting their sizes, luminosities, and thus positions on the H-R Diagram. Description: Long-term photometric variability is the focus of this paper. Here we use data sets on 76 M dwarfs spanning up to 17 years that have been acquired at the CTIO/SMARTS 0.9 m telescope as part of the RECONS astrometry/photometry program. The V magnitudes were obtained from our own work and various carefully vetted sources, primarily from Bessel (1990A&AS...83..357B), Weis (1994AJ....107.1135W, 1996AJ....112.2300W), and Koen et al. (2010, J/MNRAS/403/1949). The K magnitudes are K_s_ (hereafter, simply K) from 2MASS (Skrutskie et al. 2006, Cat. VII/233). Distances are calculated using the weighted mean trigonometric parallaxes from the CTIOPI (Cerro Tololo Inter-American Observatory Parallax Investigation) project and additional references listed in Table 1. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table1.dat 116 76 Properties of the Target Stars -------------------------------------------------------------------------------- See also: I/174 : Yale Trigonometric Parallaxes Preliminary (van Altena+ 1991) VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006) I/311 : Hipparcos, the New Reduction (van Leeuwen, 2007) J/AJ/129/413 : New high proper motion stars (-90pm>=0.18"/yr (Boyd+, 2011) J/AJ/142/92 : New proper motion stars with pm>=0.18"/yr (Boyd+, 2011) J/AJ/144/64 : Solar neighborhood. XXVIII. Substellar companions (Dieterich+, 2012) J/ApJ/748/93 : K-band spectra for 133 nearby M dwarfs (Rojas-Ayala+, 2012) J/ApJ/758/56 : Young M dwarfs within 25pc. II. Kinematics (Shkolnik+, 2012) J/AJ/147/85 : Solar neighborhood. XXXIII. 45 M dwarfs (Riedel+, 2014) J/AJ/147/94 : Solar neighborhood. XXXII. L and M dwarfs (Dieterich+, 2014) J/AJ/149/5 : Solar neighborhood. XXXV. Distances to M dwarfs (Winters+, 2015) J/AJ/150/6 : Solar neighborhood. XXXVI. VRI variability of M dwarfs (Hosey+, 2015) J/AJ/152/141 : Solar neighborhood. XXXVII. RVs for M dwarfs (Benedict+, 2016) J/AJ/153/14 : Solar neighborhood XXXVIII. Nearby M dwarf systems (Winters+, 2017) J/AJ/154/32 : Solar neighborhood. XXXIX. Nearby white dwarfs (Subasavage+, 2017) Byte-by-byte Description of file: table1.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 13 A13 --- Name Target star name 15- 16 I2 h RAh Hour of Right Ascension (J2000) 18- 19 I2 min RAm Minute of Right Ascension (J2000) 21- 22 I2 s RAs Second of Right Ascension (J2000) 24 A1 --- DE- Sign of the Declination (J2000) 25- 26 I2 deg DEd Degree of Declination (J2000) 28- 29 I2 arcmin DEm Arcminute of Declination (J2000) 31- 32 I2 arcsec DEs Arcsecond of Declination (J2000) 34- 38 F5.2 mag Vmag [9.85/15.22] Johnson V band magnitude 40- 44 F5.2 mag Imag [7.17/11.76]? Cousins I band magnitude 46- 49 F4.2 mag V-Ks [3.92/6.23] V-K_s_ color index 51- 54 F4.1 pc Dist [3/47.1] Distance 56- 60 A5 --- r_Dist Reference for Dist (1) 62- 66 F5.2 mag VMag [8.87/14.73] Absolute V band magnitude 68- 72 F5.2 mag e_VMag [-2.94/2.22] Uncertainty in VMag 74- 84 A11 "date" Date1 First date of observation 86- 96 A11 "date" Date2 Last date of observation 98-102 F5.2 yr Dur [2.26/17] Duration of observation 104-106 I3 --- Nfr [33/406] Number of frames 108-112 F5.1 mmag Var [6.3/124.1] Magnitude of the variability (2) 114-116 A3 --- n_Name Note on Name (3) -------------------------------------------------------------------------------- Note (1): Reference as follows: Cos05 = Costa et al. (2005AJ....130..337C); Cos06 = Costa et al. (2006AJ....132.1234C); Dav15 = Davison et al. (2015AJ....149..106D); Gat08 = Gatewood (2008, J/AJ/136/452); Hen06 = Henry et al. (2006AJ....132.2360H); Jao05 = Jao et al. (2005AJ....129.1954J); Jao11 = Jao et al. (2011AJ....141..117J); Lur14 = Lurie et al. (2014AJ....148...91L); Rie10 = Riedel et al. (2010AJ....140..897R); Rie11 = Riedel et al. (2011AJ....142..104R); Rie14 = Riedel et al. (2014, J/AJ/147/85); Shk12 = Shkolnik et al. (2012, J/ApJ/758/56); vLe07 = van Leeuwen (2007, Cat. I/311); YPC95 = van Altena et al. (1995, Cat. I/174). Note (2): For this study we define photometric variability as the standard deviation in the flux of a target star, in milli-magnitudes (mmag), when compared to a set of reference stars in the same field. Note (3): Note as follows: Y = Known young star; S = Known subdwarf star; (S) = Suspected, but unconfirmed subdwarf star. -------------------------------------------------------------------------------- History: From electronic version of the journal References: Henry et al., Paper I 1994AJ....108.1437H Kirkpatrick et al., Paper II 1995AJ....109..797K Simons et al., Paper III 1996AJ....112.2238S Henry et al., Paper IV 1997AJ....114..388H Patterson et al., Paper V 1998AJ....115.1648P Henry et al., Paper VI 2002AJ....123.2002H Jao et al., Paper VII 2003AJ....125..332J Hambly et al., Paper VIII 2004AJ....128..437H Golimowski et al., Paper IX 2004AJ....128.1733G Henry et al., Paper X 2004AJ....128.2460H Deacon et al., Paper XI 2005AJ....129..409D Subasavage et al., Paper XII 2005AJ....129..413S, Cat. J/AJ/129/413 Jao et al., Paper XIII 2005AJ....129.1954J Costa et al., Paper XIV 2005AJ....130..337C Subasavage et al., Paper XV 2005AJ....130.1658S, Cat. J/AJ/130/1658 Costa et al., Paper XVI 2006AJ....132.1234C Henry et al., Paper XVII 2006AJ....132.2360H Finch et al., Paper XVIII 2007AJ....133.2898F, Cat. J/AJ/133/2898 Subasavage et al., Paper XIX 2007AJ....134..252S, Cat. J/AJ/134/252 Subasavage et al., Paper XX 2008AJ....136..899S Subasavage et al., Paper XXI 2009AJ....137.4547S Riedel et al., Paper XXII 2010AJ....140..897R Winters et al., Paper XXIII 2011AJ....141...21W, Cat. J/AJ/141/21 Jao et al., Paper XXIV 2011AJ....141..117J Boyd et al., Paper XXV 2011AJ....142...10B, Cat. J/AJ/142/10 Riedel et al., Paper XXVI 2011AJ....142..104R Boyd et al., Paper XXVII 2011AJ....142...92B, Cat. J/AJ/142/92 Dieterich et al., Paper XXVIII 2012AJ....144...64D, Cat. J/AJ/144/64 Cantrell et al., Paper XXIX 2013AJ....146...99C Mamajek et al., Paper XXX 2013AJ....146..154M Jao et al., Paper XXXI 2014AJ....147...21J Dieterich et al., Paper XXXII 2014AJ....147...94D, Cat. J/AJ/147/94 Riedel et al., Paper XXXIII 2014AJ....147...85R, Cat. J/AJ/147/85 Lurie et al., Paper XXXIV 2014AJ....148...91L Winters et al., Paper XXXV 2015AJ....149....5W, Cat. J/AJ/149/5 Hosey et al., Paper XXXVI 2015AJ....150....6H, Cat. J/AJ/150/6 Benedict et al., Paper XXXVII 2016AJ....152..141B, Cat. J/AJ/152/141 Winters et al., Paper XXXVIII 2017AJ....153...14W, Cat. J/AJ/153/14 Subasavage et al., Paper XXXIX 2017AJ....154...32S, Cat. J/AJ/154/32 Bartlett et al., Paper XXXX 2017AJ....154..151B, Cat. J/AJ/154/151 Jao et al., Paper XLII 2017AJ....154..191J, Cat. J/AJ/154/191 Riedel et al., Paper XLIII 2018AJ....156...49R, Cat. J/AJ/156/49 Henry et al., Paper XLIV 2018AJ....155..265H, Cat. J/AJ/155/265 Winters et al., Paper XLV 2019AJ....157..216W ================================================================================ (End) Tiphaine Pouvreau [CDS] 08-Jun-2018