;+ 
; NAME: OHM83 
;        
; PURPOSE: 
;       To generate a synthetic spectrum of the OH M (8,3) band. 
;        
; CATEGORY: 
;        
; CALLING SEQUENCE: 
;       OHM83,TEMP,HW,W1,Y [,PS=PS] 
;        
; INPUTS: 
;       TEMP: The rotational temperature in calvins. 
; 
;       HW: FWHM , in angstroms. 
; 
; KEYWORD PARAMETERS: 
;       PS: Will produce a poscript file for the synthetic spectrum. 
; 
; OUTPUTS: 
;       W1: A 1-d array containing the wavelengths of the spectrum  
;           in angstroms. 
; 
;       Y: A 1-d array containing the relative brightness of the 
;          spectrum,corresponding to the wavelengths contained in W1. 
; 
; COMMON BLOCKS: 
;       None. 
; 
; SIDE EFFECTS: 
;       If the keyword is set, the postscript file ......  is produced. 
; 
; RESTRICTIONS: 
;       The file ..../oh83wsf.chv must exist, as it will hold the rotational 
;       line wavelenghts, oscillator strength, rotational term values, ect., 
;       that are needed to generate the synthetic spectrum. 
;        
; PROCEDURE: 
;       .... 
; 
; MODIFICATION HISTORY: 
;       Modified July 19, 1994, by T A Oliynyk 
;                        
;- 
 
PRO ohm83,temp,hw,w1,y 
 
d=FLTARR(114) 
w1=FINDGEN(6000)*0.1+7100 
 
path='c:\idl\synspec\' 
filename=path+'oh83wsf.chv' 
OPENR,unit,filename,/GET_LUN 
READF,unit,d 
FREE_LUN,unit,unit 
 
d=REFORM(d,3,38) 
w=d(0,0:*) 
s=d(1,0:*) 
f=d(2,0:*) 
 
power=EXP((-1.4387893/temp)*f) 
ym=s*((10000./w)^3)*power 
 
y=FLTARR(6000) 
I4=FIX(10.*hw) 
 
i1=FIX((w-7100.)*10.) 
i2=i1+i4 
i3=i1-i4 
 
FOR i=0,37 DO BEGIN 
  FOR j=i3(i),i2(i) DO BEGIN 
    strt=j-i1(i) 
    IF strt LT 0 THEN y(j)=y(j)+ym(i)*(j-i3(i))/i4
    IF strt EQ 0 THEN y(j)=y(j)+ym(i)
    IF strt GT 0 THEN y(j)=y(j)+ym(i)*(i2(i)-j)/i4     
  ENDFOR 
ENDFOR 

nozero=WHERE(y)
lower=MIN(nozero,MAX=upper)
lower=w1(lower)-20  
upper=w1(upper)+20
T=STRTRIM(temp,2) 
halfmax=STRING(hw,FORMAT='(F4.2)') 
PLOT,w1,y,TITLE='OH (8,3)Band, Temp.: '+T+' (K), FWHM: '+HALFMAX+' (A),  S-HL',$ 
     XTITLE='Wavelength (A)',YTITLE='Intensity (arbitrary units)',XRANGE=[lower,upper] 
 
IF KEYWORD_SET(ps) THEN BEGIN 
  psfilename=path+'oh83wsf.ps'
  psopen,psfilename 
  PLOT,w1,y,TITLE='OH (8,3)Band, Temp.: '+T+' (K), FWHM: '+HALFMAX+' (A),  S-HL',$ 
     XTITLE='Wavelength (A)',YTITLE='Intensity (arbitrary units)',XRANGE=[lower,upper] 
  psclose 
ENDIF
  

 
END