;+ ; ; Project : s3drs reconstruction software ; ; Name : get_istd_nd ; ; Purpose : part of Pixon, part of the s3drs GUI ; ; Explanation: part of the Pixon wrappers used to access and ; manipulate the various arcane Pixon structures and objects. ; ; modified get_istd to accept input params for a single ; image rather than presuming global values. ; ; Use : typically called from 's3drs.pro' ; ; Inputs : (various) ; ; Outputs : (various) ; ; Keywords : (various) ; ; Common : none ; ; Restrictions: none ; ; Side effects: none ; ; Category : reconstruction, pixon ; ; Prev. Hist. : None. ; ; Written : Sandy Antunes, NRC, March-April 2005-2009 ; ;- ; modified get_istd to accept input params for a single ; image rather than presuming global values. ; models = ; 0: "Paris", at 555e-7cm, returns photons/sec/cm^2/sr/A ; 1: FWHM=1000 centered at 7000A and 0.2 efficiency, photons/sec/cm^2/sr/A ; 2: 100% efficiency at 7000A (1A wide), photons/sec/cm^2/sr/A ; 3: erg/sec/cm^2/sr/A (not photons) ; 4: B/B0 (not photons) ; 5: Cor2A DN (akin to B/B0 less the dn2msb 2.7E-12 factor) ; 6: variant of 2, photons-per ; 7: variant of 3, ergs-per ; ; optional 'w0' (in A) provides an alternative central wavelength than 7000A ; for models 2 and 3 ;function get_istd_Nd,model,stereo_in,ImI0=ImI0,w0=w0 function get_istd_Nd,model,L0,n0,L0tau,ImI0=ImI0 ; version 05 modified by Sandy Antunes ; Calculate Istd ; input model - instrument model ; stereo_in input structure ; ImI0 ratio of Im/I0 as calculated by the flimb (for model 0 only) ; Cox, Arthur N., "Allen's Astrophysical ; Quantities/editor, Arthur Cox", Springer-Verlag, 14th ed., NY, 2000. ;-------------------------------------------------------------------------------- ; some shorter names for input data ;L0 = stereo_in.L0 ; average satellite distance ;L0tau = stereo_in.L0tau ; L0*plate scale ;n0 = stereo_in.n0 ; standard electron density (electrons/cc) ; ----- Physical Constants e2 = 23.070796e-20 ; elementary charge squared (esu) [Allen] m = 9.109389754e-28 ; electron mass (g) [Allen] c = 2.99792458e10 ; speed of light (cm/sec) [Allen] ss = (e2/(m*c*c))^2 ; Thompson Cross section (cm^2/sr), roughly 7.94e-26 AU = 1.495979e13 ; 1 AU (cm) [Allen] h = 6.6260755e-27 ; Planck's constant (erg-sec) [Allen] Im = 2.009e10 ; mean solar intensity (erg/sec/cm^2/sr) [Allen] rsun = 6.65997e10 ; solar radius in cm (cm) [Allen] ; ----- duplicate Allen's data ; wavelength (A) wA = [20,22,24,26,28,30,32,34,36,37,38,39,40,41,42,43,44,45,46,48,50,55,$ 60,65,70,75,80,90,100,$ 110,120,140,160,180,200,250,300,400,500]*.01 wA=wA*1.0e4 ; central intensity (erg/sec/cm^2/sr/A) IwA = [1.4,13,13,37,60,134,167,189,196,228,216,208,297,338,345,312,361,387,$ 395,384,361,343,317,281,246,218,194,157,125,101,84,56,40,27,18,8.1,$ 4.1,1.35,.57]*0.01 IwA=IwA*1.0e6 IwAerg=IwA; save for later photon-free alternative values ; convert IwA to photons (photons/sec/cm^2/sr/A) IwA = IwA*wA*1.0e-8/(h*c) ; ----- calculate proportionality constant K ; whoops, Paul erred by using AU, not rsun, as the unit factor here ;;K = !pi*ss*L0tau^3*n0*AU/(2*L0^2) ;;K = K*L0^2/L0tau^2 K = (!pi/2.0) * l0tau * rsun * ss * n0 ; ----- resample w and Iw to a finer grid dw = 1.0d0 ; w = scale_tomo(min(wA),max(wA),dw) w = scale(min(wA),max(wA),dw) Iw = interpol(IwA,wA,w) Iwerg = interpol(IwAerg,wA,w) ; ----- Implement Model case model of 0: begin ; Paris, Palo Alto wl = 555.0e-7 ; typical solar wavelength (cm) if (n_elements(ImI0) eq 0) then ImI0=1.0 Istd = K*0.1*(Im/ImI0) ; (erg/sec/cm^2/sr/A) Istd = Istd*wl/(h*c) ; convert to photons (photon/sec/cm^2/sr/A) end 1: begin ; 1000A width @ 7000A and 0.2 efficiency FWHM=1000. ; width of instrument function w0 = 7000. ; central wavelength Q0 = 0.2 ; peak efficiency v = FWHM/(2*sqrt(2*alog(2))) ; variance Q=Q0*exp(-(w-w0)^2/(2*v*v)) ; efficiency function Istd = K*total(Q*Iw)*dw end 2: begin ; 1A 100% efficiency, returns photons per if (n_elements(w0) eq 0) then w0 = 7000. ; central wavelength index= floor(mean(where (wA ge w0*0.95 and wA le w0*1.05))) Istd = K * IwA[index] end 3: begin ; returns ergs per, not photons per if (n_elements(w0) eq 0) then w0 = 7000. ; central wavelength index= floor(mean(where (wA ge w0*0.95 and wA le w0*1.05))) Istd = K * IwAerg[index] ; (erg/sec/cm^2/sr/A) end 4: begin ; for proportionality work Istd = K end 5: begin ; assumes Cor2A DN Istd = K / 2.7E-12 end 6: begin ; 1A width @ 7000A and 1.0 efficiency, photons ; should give the same answer as 2 FWHM=1. ; width of instrument function w0 = 7000. ; central wavelength Q0 = 1.0 ; peak efficiency v = FWHM/(2*sqrt(2*alog(2))) ; variance Q=Q0*exp(-(w-w0)^2/(2*v*v)) ; efficiency function Istd = K*total(Q*Iw)*dw end 7: begin ; 1A width @ 7000A and 1.0 efficiency, ergs ; should give the same answer as 3 FWHM=1. ; width of instrument function w0 = 7000. ; central wavelength Q0 = 1.0 ; peak efficiency v = FWHM/(2*sqrt(2*alog(2))) ; variance Q=Q0*exp(-(w-w0)^2/(2*v*v)) ; efficiency function Istd = K*total(Q*Iwerg)*dw end 8: begin ; no conversion (returns Pixon's 'dimensionless' units) Istd=1.0 end 9: begin ; spatial conversion only Istd= l0tau * rsun end 10: begin ; geometric value: ; area subtended (in pi/2 * cm) * cross section (in cm^2/sr) ; Istd= (!pi/2.0) * l0tau * rsun * ss Istd = K end 11: begin ; geometric value as per 10, but assuming DN ; area subtended (in pi/2 * cm) * cross section (in cm^2/sr) ; Istd= (!pi/2.0) * l0tau * rsun * ss / 2.7E-12 Istd = K/2.7E-12 end else: stop,'bad model = '+string(model) end return, Istd end