J/A+A/469/309 Chromospheric activity in late-type stars (Cincunegui+, 2007)
Hα and the CaII H and K lines as activity proxies for late-type stars.
Cincunegui C., Diaz R.F., Mauas P.J.D.
<Astron. Astrophys., 469, 309-317 (2007)>
=2007A&A...469..309C 2007A&A...469..309C
ADC_Keywords: Stars, late-type ; Spectroscopy
Keywords: stars: late-type - stars: activity - stars: chromospheres
Abstract:
The main chromospheric activity indicator is the S index, which is
the ratio of the flux in the core of the CaII H and K lines to the
continuum nearby, and is well studied for stars from F to K. Another
chromospheric proxy is the Halpha line, which is believed to be
tightly correlated with the CaII index.
In this work we characterize both chromospheric activity indicators,
the one associated with the H and K CaII lines and the other with
Halpha, for the whole range of late type stars, from F to M.
Description:
We present periodic medium-resolution echelle observations covering
the complete visual range, taken at the CASLEO Argentinean Observatory
over 7 years. We use a total of 917 flux-calibrated spectra for 109
stars that range from F6 to M5. We statistically study these two
indicators for stars of different activity levels and spectral types.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 127 109 Stars included in the sample
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See also:
J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)
J/A+AS/124/359 : CaII triplet lines in cool stars (Mallik 1997)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name HD or GJ name
11- 16 A6 --- GJ GJ or Gliese designation
18- 32 A15 --- OName Other name
33- 36 A4 --- Note Notes (1)
38- 45 A8 --- SpType MK spectral type
47- 52 F6.3 mag Vmag V magnitude
54- 58 F5.3 mag B-V B-V colour index
60 A1 --- n_B-V [a] a: photometry from Simbad, else from
HIP (Cat. I/239)
62- 67 F6.2 mas plx ?=- Parallax
69 A1 --- n_plx [b] b: parallax from Simbad, else from
Jenkins (1952, UCTP, Cat. I/81)
70- 74 F5.2 --- logg ?=- Gravity surface
76 A1 --- l_[Fe/H] Limit flag on [Fe/H]
77- 81 F5.2 [Sun] [Fe/H] ?=- Metallicity
83 A1 --- n_[Fe/H] [c] c: logg and [Fe/H] from Cayrel de Strobel
et al. (2001, Cat. III/221), else from
Cayrel de Strobel et al. (1997, Cat. III/200)
85 A1 --- l_Prot Limit flag on Prot
86- 90 F5.2 d Prot ?=- Rotational period
92 A1 --- r_Prot [edfghiZz] Reference for Prot (2)
94- 95 I2 --- Nobs Number of observations
97-100 F4.2 --- Mean activity index (in Mount Wilson units)
102-107 F6.2 hW/m2/nm Average surface flux in CaII HK line (4)
109 A1 --- --- [(] FHa excluded from our analysis (3)
110-114 F5.2 kW/m2/nm <FHa> Average flux in Halpha line (4)
115 A1 --- --- [)] FHa excluded from our analysis (3)
117-121 F5.2 --- m ?=- Slope of the linear regression between
F(Halpha) and F(HK) for the individual spectra
of each star
123-127 F5.2 --- rho ?=- Correlation coefficient corresponding to m
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Note (1): Notes as follows:
* = stars with planets
+ = RS CVn type
++ = BY Dra type
S = stars reported in CTIO as non-variable, which were used to
calibrate the S indices
t = dMe stars, or stars presumably active
Note (2): Prot references as follows:
e = Baliunas et al. (1996ApJ...457L..99B 1996ApJ...457L..99B),
d = Saar & Osten (1997MNRAS.284..803S 1997MNRAS.284..803S),
f = Noyes et al. (1984ApJ...279..763N 1984ApJ...279..763N),
g = Saar et al. (1990A&A...235..291S 1990A&A...235..291S),
h = Hooten & Hall (1990ApJS...74..225H 1990ApJS...74..225H)
i = Pettersen (1989AetA...209..279P).
Z = periods estimated from vsini using Glebocki & Stawikowski
(2000AcA....50..509G 2000AcA....50..509G)
z = periods estimated from vsini using Reiners & Schmitt
(2003A&A...398..647R 2003A&A...398..647R).
Note (3): The Halpha fluxes between parentheses were excluded from our
analysis in Section 4.1, since they might be subject to larger errors
due to the use of B-V as a proxy for Teff for stars with B-V≤1.4.
Note (4): CaII flux in 104erg/cm2/s/Å, and
Hα flux in 105erg/cm2/s/Å.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Oct-2007