ChromaStarDB (formerly "GrayStarServerDB")

openStars approximate stellar atmosphere and spectrum synthesis modeling in Java. User interface in JavaScript + HTML5. Hover for tips. Click for data coordinates. Ctrl +/- to zoom


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Stellar parameters
Effective temperature, Teff
Log10 surface gravity, log(g)
(0.0 - 5.5 cm s-2 = dynes g-1)
Metal content
(log10 0.001 - 10.0 x solar)
Microturbulence, ξ T , (0.0 - 8.0 km s-1)
Stellar mass
(0.1 - 20.0 MSun)
κFudge log10 mass extinction (-2.0 - 2.0 log cm2 g-1)
[He/Fe] (-1 - 1)
[C/O] (-2 - 2)
[α/Fe] (-0.5 - 0.5)

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Habitable Planet Zone parameters
Surf pressure
(0.6 - 22000 kPa)
Greenhouse effect, ΔT
(-200 - +600 K)
Albedo (0.0 - 0.95)
Organic solvent
Water Methane Ammonia Carbon dioxide

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Spectrum synthesis parameters
Warning: Inreasing the range between λStart and λStop or decreasing the ratio κl/κc will increase the computing time significantly.
View the ascii line list
Minimum log10κl/κc for inclusion (-4.0 - 6.0)
Log10 Broadening enhancement, γExtra (0.0 - 1.0)
λStart (260 - λStop nm)
λStop (λStart - 2600 nm)
Minχl (0 - Max χl eV)
Maxχl (Min χl - χI eV)
Min log10 fij (-6.0 - Max fij)
Max log10 fij (Min log10 fij - 2.0)
RV (-200 to +200 km s-1)
vMacro (0 - 8 km s-1)
vRot (0 - 20 km s-1)
iRot (0 - 90 o)
λ-scale in vac/air: Vacuum Air Spectral line λ sampling: Coarse (good for quick recon only) Fine
Included species
Big bang α-process Fe-group n-capture
All species No species
Ionization stages
H He Li Be B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ge
Rb Sr Cs Ba
JOLA Molecules
TiO bands
(C3Δ-X3Δ, c1Φ-a1Δ, A3Φ-X3Δ)

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Narrow band Gaussian filter λ, (270 - 2550 nm) σ, (0.005 - 10 nm)
Plots: Spectrum synthesis (Warning: Slow) Atmosphere Chem Eq (if Atmos plots ON) Radiation field
Detailed print-out (below graphs): None Spectrum synthesis Atmospheric structure Flux spectral energy distribution (SED) Specific intensity distribution Limb darkening coeffs Partial pressures A12 abundances JSON string