Chromospheric Activity

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Criteria for spectral classification of cool
stars using high resolution spectra
Spanish Virtual Observatory
The Virtual Observatory in action new science,
new technology, and next generation facilities.
IAU XXVI General Assembly, Special Session 3
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Libraries of stellar spectra in the web
http//www.ucm.es/info/Astrof/invest/actividad/spe
ctra.html
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Libraries of stellar spectra

• Applications
• Stellar spectral classification.
• Determination of atmospheric parameters (Teff,
  g, Fe/H).
• Test models of stellar atmospheres.
• Reference stars for spectral subtraction
  (chromospheric activity).
• Spectral synthesis applied to composite systems.
  
• Spectral synthesis of the stellar population of
  galaxies.

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Libraries of stellar spectra (Montes et al. 1997,
1998, 1999)
Spectra of cool stars (F, G, K, M)

• I. (Montes et al. 1997)
• AA Supp.S., 123, 473
• intermediate resolution (0.2-3 Å)
• IDS/INT, Coudé/2.2m
• CaII HK,
• Hß,
• NaI D1, D2 HeI D3,
• Ha
• 170 spectra,
• 116 stars (V, IV, III)

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Libraries of stellar spectra (Montes et al. 1997,
1998, 1999)
Spectra of cool stars (F, G, K, M)

• II. (Montes Martín 1998)
• AA Supp.S., 128, 485,
• high resolution (0.09-1.19 Å)
• UES/WHT
• echelle (4800 10600 Å)
• 105 spectra,
• 83 stars (V)

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Libraries of stellar spectra (Montes et al. 1997,
1998, 1999)
Spectra of cool stars (F, G, K, M)

• III. (Montes, Ramsey Welty 1999)
• ApJ Supp. S., 123, 283,
• intermediate resolution (0.5 Å)
• FOE/0.9m-2.1m KPNO
• echelle (3900 9000 Å)
• 345 spectra,
• 130 stars (V, IV, III, II, I)

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Other stellar spectra (available soon at the VO)
FOCES (Fibre Optic Cassegrain Echelle
Spectrograph) Calar Alto Observatory (Almería,
Spain), 2.2m telescope

• High resolution echelle spectra
• (0.1-0.3 Å) R 40000 - 50000
• Several observing runs from 1999 2006

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Other stellar spectra (available soon at the VO)
Spectrum of HD 42807 (FOCES)
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6410 6450 Å spectral line region
FeII l6432.68 Å
CaI l6439.08 Å
FeI l6430.85 Å
FOCES
Representative spectra of Main Sequence stars (F7
M0)
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6410 6450 Å spectral line region
FeII l6432.68 Å
CaI l6439.08 Å
FeI l6430.85 Å
FOCES
Representative spectra of Giant stars (G2 M3)
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5855 5875 Å spectral line region
TiI l5866.45 Å
FOCES
Representative spectra of Main Sequence stars (F7
M0)
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5855 5875 Å spectral line region
TiI l5866.45 Å
FOCES
Representative spectra of Giant stars (F7 M0)
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Other stellar spectra (available soon at the VO)
http//hebe.as.utexas.edu/s4n/ A complete
spectroscopic catalog of  stars with spectral
types brighter than K2V within 47 years-light
from the Sun. The resulting database contains
high-resolution optical spectra for 118 nearby
stars. R 50000, continuous spectral coverage
between 3620 - 9210 Å, and typical
signal-to-noise ratios in the range 150 - 600.
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6410 6450 Å spectral line region
FeII l6432.68 Å
CaI l6439.08 Å
FeI l6430.85 Å
Representative spectra of Main Sequence stars (F8
- K3)
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5855 5875 Å spectral line region
TiI l5866.45 Å
Representative spectra of Main Sequence stars (F8
- K3)
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Synthetic spectra (Kurucz Models)
Representative synthetic spectra of Main
Sequence stars (Teff 6500 3500 K), solar
abundance calculated with Kurucz models, with the
same spectral resolution that FOCES and S4N
spectra
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Synthetic spectra (Kurucz Models)
FeII l6432.68 Å
CaI l6439.08 Å
6410 6450 Å spectral line region
FeI l6430.85 Å
Representative synthetic spectra of Main
Sequence stars (6500 3500 K) calculated with
Kurucz models
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Synthetic spectra (Kurucz Models)
5855 5875 Å spectral line region
TiI l5866.45 Å
Representative synthetic spectra of Main
Sequence stars (6500 3500 K) calculated with
Kurucz models
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HR Diagram
Filled symbols MK spectral type standards
General Catalogue of Stellar Spectral
Classifications (Skiff B.A., Lowell Observatory
(2005))
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EW Measurements
- All the spectra shifted to the rest
wavelength - EW determined in the same way in all
the spectra using the SBANS task of IRAF
lc
Width
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V
(EW, B-V) Diagram
Filled symbols MK spectral type standards
CaI l6439.08 Å
III
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V
(EW, B-V) Diagram
FeI l6430.85 Å
Filled symbols MK spectral type standards
III
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V
(EW, B-V) Diagram
Filled symbols MK spectral type standards
FeI l6430.85 Å
FeII l6432.68 Å
III
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V
(EW, B-V) Diagram
Filled symbols MK spectral type standards
TiI l5866.45 Å
III
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(EW, B-V) Diagram
Filled symbols MK spectral type standards
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(EW, B-V) Diagram
MI6 Index 6 of Malyuto Schmidt-Kaler (1997)
(l5125-5245 / l5245-5290)
Filled symbols MK spectral type standards
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http//www.ucm.es/info/Astrof/invest/actividad/spe
ctra.html