J/A+A/566/A95 C-rich giants synthetic spectrophotometry. IV (Eriksson+, 2014)
Synthetic photometry for carbon-rich giants.
IV. An extensive grid of dynamic atmosphere and wind models.
Eriksson K., Nowotny W., Hofner S., Aringer B., Wachter A.
<Astron. Astrophys. 566, A95 (2014)>
=2014A&A...566A..95E 2014A&A...566A..95E
ADC_Keywords: Stars, variable ; Stars, giant ; Models ; Spectrophotometry
Keywords: stars: AGB and post-AGB - stars: atmospheres - stars: carbon -
stars: variables: general - stars: mass-loss - circumstellar matter
Abstract:
The evolution and spectral properties of stars on the asymptotic giant
branch (AGB) are significantly affected by massloss through dusty
stellar winds. Dynamic atmosphere and wind models are an essential
tool for studying these evolved stars, both individually and as
members of stellar populations, to understand their contribution to
the integrated light and chemical evolution of galaxies.
This paper is part of a series with the purpose of testing
state-of-the-art atmosphere and wind models of C-type AGB stars
against observations, and making them available to the community for
use in various theoretical and observational studies.
We have computed low-resolution spectra and photometry (in the
wavelength range 0.35-25um) for a grid of 540 dynamic models with
stellar parameters typical of solar-metallicity C-rich AGB stars and
with a range of pulsation amplitudes. The models cover the dynamic
atmosphere and dusty outflow (if present), assuming spherical
symmetry, and taking opacities of gas-phase species and dust grains
consistently into account. To characterize the time-dependent dynamic
and photometric behaviour of the models in a concise way we defined a
number of classes for models with and without winds.Results.
Comparisons with observed data in general show a quite satisfactory
agreement for example regarding mass-loss rates vs. (J-K) colours or
K magnitudes vs. (J-K) colours. Some exceptions from the good
overall agreement, however, are found and attributed to the range of
input parameters (e.g. relatively high carbon excesses) or intrinsic
model assumptions (e.g. small particle limit for grain opacities).
While current results indicate that some changes in model assumptions
and parameter ranges should be made in the future to bring certain
synthetic observables into better agreement with observations, it
seems unlikely that these pending improvements will significantly
affect the mass-loss rates of the models.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tableb1.dat 107 540 Photometric and dynamic properties of the
models in the present grid
list.dat 66 540 List of directories in DMAfilters and DMAspectra
DMAfilters.tar 512 5121 *All photometric files
DMAspectra.tar 512 17135 *All spectroscopic files
--------------------------------------------------------------------------------
Note on DMAfilters.tar: contains the directory DMAfilters.
Note on DMAspectra.tar: contains the directory DMAspectra.
--------------------------------------------------------------------------------
Description of DMAfilters.tar:
For each model there are a number of files with photometry data, one for
each epoch, and there are up to five different epochs per model, typically
two epochs. Each of these files contains photometry data for at least two
pulsation periods.
The files are in the following format:
Byte-by-byte Description of file: DMAfilters/*/*
------------------------------------------------------------------------------
Bytes Format Units Label Explanations
------------------------------------------------------------------------------
3- 8 F6.3 mag Bmag Synthetic Johnson-Cousins B magnitude (1)
11- 16 F6.3 mag Vmag Synthetic Johnson-Cousins V magnitude (1)
19- 24 F6.3 mag Rmag Synthetic Johnson-Cousins Rc magnitude (1)
27- 32 F6.3 mag Imag Synthetic Johnson-Cousins I magnitude (1)
35- 40 F6.3 mag Jmag Synthetic Johnson-Glass J magnitude (1)
43- 48 F6.3 mag Hmag Synthetic Johnson-Glass H magnitude (1)
51- 56 F6.3 mag Kmag Synthetic Johnson-Glass K magnitude (1)
58- 64 F7.3 mag Lmag Synthetic Johnson-Glass L magnitude (1)
66- 72 F7.3 mag L'mag Synthetic Johnson-Glass L' magnitude (1)
74- 80 F7.3 mag Mmag Synthetic Johnson-Glass M magnitude (1)
83- 88 F6.3 mag J2mag Synthetic 2MASS J magnitude
91- 96 F6.3 mag H2mag Synthetic 2MASS H magnitude
99-104 F6.3 mag Ks2mag Synthetic 2MASS Ks magnitude
107-112 F6.3 --- Phase Pulsational phase, with luminosity maxima at
0.0, 1.0 etc.
115-120 I6 --- Snapshot Snapshot identification number
(timestep number)
------------------------------------------------------------------------------
Note (1): B,V,R,I; see Bessell 1990PASP..102.1181B 1990PASP..102.1181B), and in the Johnson-Glass
(J, H, K, L, L', M; see Bessell and Brett 1988PASP..100.1134B 1988PASP..100.1134B)
------------------------------------------------------------------------------
Description of DMAspectra.tar:
For each model there are a number of directories, one for each epoch, and
there are up to five different epochs per model, typically two epochs.
Each of these directories contains files (spectra) for a number of
snapshots, typically at least forty (about twenty per pulsation period,
and at least two periods).
All directories contains a modelinfo.dat file, and the spectra
as *.isp file names.
The files are in the following format:
Byte-by-byte Description of file: DMAspectra/*/*/*.isp
------------------------------------------------------------------------------
Bytes Format Units Label Explanations
------------------------------------------------------------------------------
2- 11 F10.3 0.1nm lambda Wavelength
15- 22 F8.5 --- Flux Continuum normalized flux (i.e. Normalized to
calculation without atomic and molecular line
opacities)
24- 35 E12.6 10-7W nu*Lnu nu*Lnu or lambda*Llambda
37- 48 E12.6 10-7W e_nu*Lnu Error on nu*Lnu or lambda*Llambda
------------------------------------------------------------------------------
--------------------------------------------------------------------------------
See also:
J/A+A/503/913 : Synthetic spectrophotometry for C-rich giants (Aringer+, 2009)
http://www.astro.uu.se/AGBmodels : AGBmodels Home Page
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 K T* [2600/3200] Stellar effective temperature
(2600, 2800, 3000, 3200)
6- 9 F4.2 [Lsun] logL* Stellar luminosity
(3.55, 3.70, 3.85, 4.00)
11- 14 F4.2 Msun M* Stellar mass (0.75, 1.0, 1.5, 2.0)
16- 18 F3.1 [-] Cex Carbon excess, log(C-O)+12
(8.2, 8.5, 8.8) (1)
20 I1 km/s Dup [2/6] Piston velocity amplitude Δup
(2, 4, 6)
22 I1 --- fL [1/2] Luminosity amplitude fL (2)
24- 25 A2 --- Cl Class of dynamic (3)
27- 31 F5.2 [cm/s2] logg Surface gravity
33- 38 F6.2 [Msun/yr] logMdot ?=- Mass loss rate
40- 43 F4.1 km/s uinf ?=- Wind velocity u∞
45- 49 F5.3 --- fc ?=- Carbon condensation degree fcond
51- 58 E8.3 --- d/g ?=- Dust-to-gas ratio ρd/ρg
60- 63 F4.2 mag DMbol Full amplitude of the bolometric magnitude
ΔMbol
65- 69 F5.2 mag Vmag Mean V magnitude
71- 75 F5.2 mag DVmag Range of V magnitudes ΔV
77- 81 F5.2 mag Kmag Mean K magnitude
83- 86 F4.2 mag DKmag Range of K magnitudes ΔK
88- 91 F4.2 mag V-I V-I colour index
93- 97 F5.2 mag V-K V-K colour index
99-102 F4.2 mag J-H J-H colour index
104-107 F4.2 mag H-K H-K colour index
--------------------------------------------------------------------------------
Note (1): on the scale where log(NH)=12.00.
Note (2): Luminosity amplitude (see Section 2.2) as follows:
1 = original value as in Hofner et al., 2003A&A...399..589H 2003A&A...399..589H
2 = newly calculated set of models
(twice the luminosity amplitude of the original grid)
Note (3): Classes of dynamic as follows:
pp = Pulsating atmosphere, periodically pulsating models,
repeating their dynamic behaviour every period
pm = Pulsating atmosphere, multi-periodic models,
models that repeat after two (sometimes more) periods
pn = Pulsating atmosphere, irregular models (non-periodic)
ws = Wind, models with a steady wind with small temporal variations
in mass-loss rates and wind velocities
wp = Wind, periodic variations in the wind properties
wn = Wind, models with more irregular behaviour (non-periodic)
we = Wind, episodic models, that show an intermittent outflow
--------------------------------------------------------------------------------
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 31 A31 --- Dir Directory name
(TTTTlLLLLmMMMz0.0CNtdrouuNlNN)
41- 44 I4 K T* Effective stellar temperature
(2600, 2800, 3000, 3200) (TTTT)
46- 49 F4.2 [Lsun] logL* Stellar luminosity
(3.55, 3.70, 3.85, 4.00) (lLLLL)
51- 54 F4.2 Msun M* List of stellar masses
(0.75, 1.0, 1.5, 2.0) (mMMM)
56- 58 F3.1 --- z [0.0] Redshift
60- 62 F3.1 --- Cex Carbon excess log(C-O)+12 (8.2, 8.5, 8.8) (CN)
64 I1 km/s Dup Piston velocity amplitude Δup (uN)
66 I1 --- fL [1/2] Luminosity amplitude fL (lNN)
--------------------------------------------------------------------------------
Acknowledgements:
Kjell Eriksson, kjell.eriksson(at)physics.uu.se
References:
Aringer et al., Paper I 2009A&A...503..913A 2009A&A...503..913A, Cat. J/A+A/503/913
Nowotny et al., Paper II 2011A&A...529A.129N 2011A&A...529A.129N
Nowotny et al., Paper III 2013A&A...552A..20N 2013A&A...552A..20N
(End) Patricia Vannier [CDS] 25-Apr-2014