Документ взят из кэша поисковой машины. Адрес оригинального документа : http://star.arm.ac.uk/~jsv/HB_cal.pro Дата изменения: Mon Apr 2 20:50:01 2007 Дата индексирования: Mon Oct 1 21:08:30 2012 Кодировка: Поисковые слова: astro-ph

PRO cal_hb,Z,teff,logL,Mass,logmdot

; ------------------------------------------------
; - -
; - MASS LOSS RECIPE for HORIZONTAL BRANCH Stars -
; - -
; ------------------------------------------------
;
; The Recipe is presented in:
;
; "Jorick S. Vink, & Santi Cassisi, 2002, A&A in press, [astro-ph/0207037]"
;
;
; The assumed Terminal Wind velocity (vinf) equals the
; escape velocity (vesc), which implies Mdot is maximal.
; As discussed in:
;
; Jorick S. Vink, & Alex de Koter, 2002, A&A in press, [astro-ph/0207170]"
;
; If one knows vinf > vesc, one may adopt the (vinf/vesc)
; dependence from the massive OB star computations in:
;
; "New theoretical mass-loss rates of O and B stars"
; Jorick S. Vink, A. de Koter, and H.J.G.L.M. Lamers, 2000, A&A 362, 295
;
; ------------------------------------------------------------

if n_params(0) eq 0 then begin
print,'cal_hb,Z,teff,logL,Mass'
print,''
print,'input:'
print,' Z - Metallicity Z compared to galactic value of Z=0.02
print,' E.g. for Z = 0.002 insert: 0.1
print,' '
print,' teff - effective temperature in Kelvin'
print,' '
print,' logL - log of Luminosity (in solar units)'
print,' '
print,' mass - Evolutionary Mass (in solar units)'
print,' '
print,'output:'
print,' '
print,' mdot - Predicted mass-loss rate'
return
endif
;
; ------------------------------------------------------------
;
msun = 1.989D33
lsun = 3.827D33
pi = 3.1415
stefb = 5.670D-5
grav = 6.670D-8

lum = 10^logL
mstar = mass*msun
lumi = lum*lsun

if (Z le 0) then begin
print,'Z value needs to be higher than 0!'
goto, Mistake
endif

logZ = alog10(Z)

logmdot = (-11.70) $
+ (2.13 * alog10(lum/(10^1.5)))$
- (1.09 * alog10(mass/0.5)) $
+ (1.07 * alog10(teff/20000.)) $
+ 0.97 * logZ

print,'the predicted mass loss rate is: log(mdot) = ',logmdot

Mistake:
return
End