J/AJ/138/312        Activity of bright solar analogs         (Hall+, 2009)
The activity and variability of the Sun and Sun-like stars.
II. Contemporaneous photometry and spectroscopy of bright solar analogs.
    Hall J.C., Henry G.W., Lockwood G.W., Skiff B.A., Saar S.H.
   <Astron. J., 138, 312-322 (2009)>
   =2009AJ....138..312H 2009AJ....138..312H
ADC_Keywords: Sun ; Stars, G-type ; Photometry
Keywords: stars: activity - Sun: activity
Abstract:
    We present 14 years of contemporaneous photometric and spectroscopic
    observations of 28 solar analog stars, taken with the Tennessee State
    University Automatic Photometric Telescopes at Fairborn Observatory
    and the Solar-Stellar Spectrograph at Lowell Observatory. These are
    the best observed and most nearly Sun-like of the targets in our
    magnitude-limited (V≤7.5) sample. The correlations between
    luminosity and activity reveal the expected inverse
    activity-brightness correlations for active stars. Strong direct
    correlations between activity and brightness are not prevalent for the
    less active solar age stars, but are precision limited.
Description:
    The HK series presented in this paper result from a reprocessing of
    our ∼30000 solar and stellar spectra following a seven month
    observing hiatus from 2008 January-July.
    We acquired the photometric observations in this paper with the T4
    0.75-m and the T8 0.8-m APTs at Fairborn Observatory.
File Summary:
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 FileName   Lrecl  Records   Explanations
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ReadMe         80        .   This file
table1.dat     39       28   Target Stars and their Properties
table3.dat     65      284   Seasonal means
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See also:
   J/A+A/468/663 : Li abundances in solar-analog stars (Takeda+, 2007)
   J/A+A/508/L17 : Abundances in solar analogs (Ramirez+, 2009)
   J/ApJS/181/62 : Survey of young solar analogs (Metchev+, 2009)
   J/A+A/515/A93 : Li abundances in solar-analog stars. II. (Takeda+, 2010)
Byte-by-byte Description of file: table1.dat
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   Bytes Format Units   Label     Explanations
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   1-  6  I6    ---     HD        Star HD number
   8-  9  I2    ---     Nseas     Number of seasons
  11- 14  F4.2  mag     Vmag      V magnitude (1)
      15  A1    ---   r_Vmag      [bcd] Reference for Vmag (2)
  17- 21  F5.3  mag     b-y       b-y colour index (1)
      22  A1    ---   r_b-y       [e] Reference for b-y (2)
  24- 30  A7    ---     SpType    MK spectral type
  32- 36  F5.2  [-]     [M/H]     Metallicity (1)
  38- 39  A2    ---     Prog      [ELM ] Programs (3)
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Note (1): Except where noted,
  * V magnitudes are from Johnson et al. (1966CoLPL...4...99J 1966CoLPL...4...99J), and
  * b-y colors are from Olsen (1993, Cat. J/A+AS/102/89, 1994, 
    Cat. J/A+AS/104/429).
  * Metal abundances are taken from Valenti & Fischer (2005,
    Cat. J/ApJS/159/141) and Gray et al. (2003, Cat. J/AJ/126/2048).
Note (2): Notes as follows:
   b = Carney (1978AJ.....83.1087C 1978AJ.....83.1087C)
   c = Mermilliod (1986EgUBV........0M 1986EgUBV........0M)
   d = Bidelman (1951ApJ...113..304B 1951ApJ...113..304B)
   e = Crawford et al. (1966AJ.....71..709C 1966AJ.....71..709C)
Note (3): Programs as follows:
   E = ELODIE (Soubiran & Triaud, 2004A&A...418.1089S 2004A&A...418.1089S)
   M = Mt. Wilson (Baliunas et al., 1995ApJ...438..269B 1995ApJ...438..269B)
   L = Lockwood et al. (2007ApJS..171..260L 2007ApJS..171..260L)
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Byte-by-byte Description of file: table3.dat
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   Bytes Format Units   Label     Explanations
--------------------------------------------------------------------------------
   1-  6  I6    ---     HD        Star HD number
   8- 13  F6.1  yr      Season    [1994/2008.4] Midpoint of photometric/HK
                                  observing season
  15- 19  F5.3  ---            Seasonal mean Mount Wilson S index
  21- 26  F6.3  [-]    <logR'HK>  Seasonal mean R'HK activity index
  28- 37  E10.3 mW/m2   DFHK      Seasonal mean excess flux in erg/s/cm2
  39- 48  E10.3 mW/m2 e_DFHK      The 1σ error in DFHK
  50- 57  F8.5  mag     (b+y)/2   Photometric brightness (1)
  59- 65  F7.5  mag   e_(b+y)/2   The 1σ error in (b+y)/2
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Note (1): Relative to grand mean of all observations.
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History:
    From electronic version of the journal
References:
    Hall et al., Paper I      2007AJ....133..862H 2007AJ....133..862H
(End)                  Greg Schwarz [AAS], Patricia Vannier [CDS]    16-Nov-2011