Version 15 June 2007 compiled: 11-11-2009 - Hamburger Sternwarte

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turbulent velocity (see above). Default = 0. (From de Koter, Hubeny,& Heap (1994) ApJ, 435, 71.) • ivelcalc: Velocity law type. 0: standard β law wind models 1: self-consistent velocity calculation (under development) 2: linear velocity law • windbeta: The exponent β in the velocity law in the case ivelcalc = 0. Typically β � 1.0 for O- and early B-type stars, up to 3.0 for late B- and A-type supergiants. • tmaxlg: Gives the maximum optical depth of the hydrostatic zone. The grid (in this zone) will be logarithmically spaced between the optical depth at the base of the wind (not known in advance) and τlayer = 10 tmaxlg . This parameter is not ignored if job=1, so make you sure you use the right value! tmaxlg = 2 for most wind models, tmaxlg = 2 to 3 for optically thick wind models. 4.4.2 Self-consistent Velocity Field (ivelcalc = 1) Parameters These models must restarted (job = 1) from an existing ivelcalc = 0 model in order to supply radiative acceleration structure required for the velocity field calculation. Both ˙ M and v(r) will be computed in this mode. • model: For all wind models, model=7. • ivelcalc: For these models ivelcalc = 1. • teff: Effective temperature [in K]. • logg: gives log(g) at the radius r0. • r0: The reference radius [in cm], used in the wind velocity law. In addition, r0 sets the luminosity of the model via L = 4πR2 0σT 4 eff , and is the radius at which logg is specified. • rmaxw: The outer radius [in cm] of the wind model, typically 200R0. In this self-consistent wind convergence scheme the temperature correction iterations and velocity field computation iterations are interleaved following each solution of the radiative transfer equation. The next four parameters allow control of the order and spacing of these iterations. • ivelcntmx: Maximum number of velocity iterations for a fixed temperature structure (default 3). • itempcntmx: Maximum number of temperature correction iterations for a fixed velocity structure (default 3). • ivelcount: start velocity iterations at this number (default 0, do velocity iterations first) • itempcount: start temp. corr. iterations at this number (default 1, do temp. corr. iterations second). 4.4.3 Additional Optional Wind Parameters These parameters, which specify the grid of the radial points, apply to all wind models. • iswlayer: Model layer for switch from dynamic to static structure (default is 30). Dynamic region from (1,...,iswlayer) and static region from (iswlayer+1,...,layer). If the total number of layers in PHOENIX is different from 50, you’ll want to change this. • irgrid: The type of radius grid construction, 0: use cosh fac, 1:use steff fac (default) • inewrgrid: For a restarted model (job = 1), 0: use radii from restart file (unit 18) (default), 1: construct new radial grid from parameters rmaxw, rtau1, and irgrid in the input file, but continue to use the temperature structure from restart file (unit 18). • steff fac: Radial points distributed using a exponential scheme from (Steffan et al.1997, A&AS, 126, 39.) of which steff fac is a scale factor (default 1.5). Adjusting this value may be useful for redistributing radial points in some cases (e.g. high-mass loss, low velocity). The grid is very sensitive to this parameter, adjust in units of 0.1. • cosh fac: Radial points distributed using a hyperbolic cosine of which cosh fac is a scale factor. Useful for redistributing radial points (default is 15), values 10-15 seem to work well. 14
• itaugrid: The type of tau-grid construction, 0: original scheme (default), 1: new adaptive scheme. • velminp: The percentage of terminal or max velocity V0 which will be the minimum velocity in the hydrodynamic layers (default is 0.0002 or 0.2 %). This sets the velocity of the lowest radial grid point in the wind. Useful to getting a good density match between the dynamic and static layers in tough cases. 4.5 Dust Clouds and Gravitational Settling parameters Over the years since the first inclusion of dust opacities in phoenix the code was subjected to several cloud models, each involving a set of input parameters, some of which are no longer supported. We list those models and their parameters and indicate which methods can still be used below. 4.5.1 General Dust Opacity Parameters These parameters concern only the use of the opacity cross-sections themselves and are required with any of the method described below. • igrains: (icond in phoenix.f) flag for use with grains: 0: grains are ignored, 1: grains are considered in the EOS but ignored in the opacity, 2: grains are consistently included in the EOS and the opacity, 3: as before, but the grains are ignored in the calculation of the PHOENIX standard optical depth grid. • dust porosity: value f of the assumed dust grain porosity to be applied as a multiplication factor to a grain’s mass density (grain rho new = (1.d0-f)* grain rho). This is done in KAPCAL/gnsize.f and KAPCAL/kapdust.f for the two main cloud methods. Must be ≤ f < 1. Default is no porosity i.e. 0.d0. • usedust: DOUBLE array with dust opacity multipliers for each individual dust ’species’ that have supported opacities. Default depend on the original setup. Setting an element of this array to zero remove that species’ opacity completely. Used to adjust dust opacities. • cloud covering factor: sets the cloud covering fraction, from 0.d0 to 1.d0 in the spectrum only (vcapdustcloud). Possibility to use a different fraction for each layer and species of dust particle for which we have an opacity profile (clouds matix), however not turned on in phoenix.f though. Default is 1.d0. • use clouds: switch to choose from cloud methods: ≤ 0: equilibrium model, > 0: settling model. 4.5.2 Rainout Model: Produce 100% grain settling i.e. all grains sedimented out and corresponding refractory metal depletion. The fraction “xout” (0 for no settling, 1 for maximum settling) can be changed the rainout.f routine directly (in KAPCAL/rainout.f). The rainout option is available in csppress.f for EOS calculations as in phoenix.f for direct mode model calculations. • rainout: Set to .TRUE. to use the RAINOUT EOS. This option is independent of other cloud models and of variables like use clouds or settleos. Rainout should be used with standard EOS parameters like ieos and idirect and with at least igrains=1. 4.5.3 Equilibrium Cloud Model: When use clouds ≤ 0 this cloud model is chosen, where number densities of grains as provided by the EOS with igrains > 1 are used in csgrain0 with a log-normal distribution of grain sizes defined in gnsize.f as called from input.f is used. This type of cloud models generate dust opacities all through 15
Page 1 and 2: Messages of the day: PHOENIX Versio
Page 3 and 4: • deviations from “local thermo
Page 5 and 6: with χs,s+1 =| χs − χs+1 |, th
Page 7 and 8: • linecom.f: module with data str
Page 9 and 10: e wrong! • Unit 19: Output files.
Page 11 and 12: • newcia: set which CIA version t
Page 13: 3. OR a velocity law for a red gian
Page 17 and 18: 4.5.5 Ad’hoc Gravitational Settli
Page 19 and 20: luminosity (used in makehydro) •
Page 21 and 22: faster if the DOME radiative transf
Page 23 and 24: • uselin: INTEGER array with flag
Page 25 and 26: • phoenix path: full pathname to
Page 27 and 28: 4.19 EOS parameters, e.g., abundanc
Page 29 and 30: References Albrow, M., An, J., Beau
Page 31 and 32: Bean, J. L., Sneden, C., Hauschildt
Page 33 and 34: Howell, S. B., Hauschildt, P. H., &
Page 35: Schweitzer, A., Hauschildt, P. H.,

Version 15 June 2007 compiled: 11-11-2009 - Hamburger Sternwarte

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