C
h
r
o
m
a
Star
DB
(formerly "GrayStarServerDB")
openStars
approximate
stellar atmosphere
and spectrum synthesis modeling in Java. User interface in JavaScript + HTML
5
.
Hover for tips. Click for data coordinates.
Ctrl +/-
to zoom
You must have a JavaScript capable browser, AND JavaScript enabled, to display ChromaStarDB
MODEL
Input:
Show/Hide stellar
Stellar
parameters
Effective temperature,
T
eff
(3400-50000)
K
)
Log
10
surface gravity, log(
g
)
(0.0 - 5.5 cm s
-2
= dynes g
-1
)
Metal content
(log
10
0.001 - 10.0 x solar)
Microturbulence,
ξ
T
, (0.0 - 8.0 km s
-1
)
Stellar mass
(0.1 - 20.0
M
Sun
)
κ
Fudge
log
10
mass extinction (-2.0 - 2.0 log cm
2
g
-1
)
[He/Fe]
(-1 - 1)
[C/O]
(-2 - 2)
[α/Fe]
(-0.5 - 0.5)
Show/Hide Exo-planet
Planetary parameters
parameters
Affects
Habitable zone
and
Transit light curve
Surf pressure
(0.6 - 22000
kPa
)
Greenhouse effect,
ΔT
(-200 - +600
K
)
Albedo
(0.0 - 0.95)
R
Orbit
(AU)
(0.01 - 50)
R
Planet
(
R
Earth
) (0.1 - 20)
i
Orb
(0 - 90
o
)
Organic solvent
Water
Methane
Ammonia
Carbon dioxide
Show/Hide spectrum synthesis
Spectrum synthesis parameters
Warning:
Inreasing the range between
λ
Start
and
λ
Stop
or decreasing the ratio
κ
l
/
κ
c
will increase the computing time significantly.
View the ascii line list
Minimum log
10
κ
l
/
κ
c
for inclusion (-4.0 - 6.0)
Log
10
Broadening enhancement,
γ
Extra
(0.0 - 1.0)
λ
Start
(260 -
λ
Stop
nm)
λ
Stop
(
λ
Start
- 2600 nm)
Min
χ
l
(0 - Max
χ
l
eV)
Max
χ
l
(Min χ
l
-
χ
I
eV)
Min log
10
f
ij
(-6.0 - Max f
ij
)
Max log
10
f
ij
(Min log
10
f
ij
- 2.0)
RV
(-200 to +200 km s
-1
)
v
Macro
(0 - 8 km s
-1
)
v
Rot
(0 - 20 km s
-1
)
i
Rot
(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
I
II
III
IV
Elements
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 (
C
3
Δ-X
3
Δ, c
1
Φ-a
1
Δ, A
3
Φ-X
3
Δ
)
Show/Hide samples
Sample pre-sets
Sample standard stars
User parameters
Sun
Vega
Regulus
Arcturus
Procyon
Planet hosts
51 Pegasi
61 Cygni A
Proxima Centauri
Fomalhaut
Sample worlds
User parameters
Earth
Venus
Mars
Titan
Sample
Fraunhofer and classification spectral lines
User parameters
Na I
D
1
Na I
D
2
Mg I
b
1
Ca II
K
Ca II
H
Ca I 4227
Fe I 4045
Fe I 4271
He I 4471
He I 4387
Show/Hide performance/realism
Modeling realism
vs
performance
No. HSE-EOS-Opac iters
No. Pe-IonEquil-MolecEquil iters
MODEL
Output:
Narrow band Gaussian filter
λ
, (270 - 2550 nm)
σ
, (0.005 - 10 nm)
Plots:
Spectrum synthesis (Warning: Slow)
Atmosphere
None
H
H+
H-
He
He+
C
C+
N
N+
O
O+
Ne
Ne+
Na
Na+
Mg
Mg+
Mg++
Al
Al+
Si
Si+
S
S+
Cl
Cl+
K
K+
Ca
Ca+
Ca++
Sc
Sc+
Ti
Ti+
V
V+
Cr
Cr+
Mn
Mn+
Fe
Fe+
Co
Co+
Ni
Ni+
Sr
Sr+
Y
Y+
Zr
Zr+
Zr+
H2
H2+
C2
C3
N2
O2
CH
C2H2
NH
NH2
NH3
OH
H2O
MgH
AlH
SiH
HS
H2S
HCl
CaH
CN
NO
CO
CO2
MgO
AlO
SiO
SO
CaO
ScO
ScO2
TiO
VO
VO2
YO
YO2
ZrO
ZrO2
CS
SiS
TiS
SiC
SiC2
NaCl
MgCl
AlCl
CaCl
HCN
HCO
MgOH
AlOH
CaOH
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
A
12
abundances
Transit light curves
JSON string