;+ ; NAME: ; IRIS_CALIB_SPECTRUM ; ; PURPOSE: ; Absolute radiometric calibration of an IRIS spectrum. By default the ; spectrum will be returned in cgs units erg cm^-2 s^-1 sr^-1 Å^-1. ; ; CATEGORY: ; Data analysis ; ; CALLING SEQUENCE: ; EBDETECT, Inputspectrum, Wavelength ; ; INPUTS: ; Inputspectrum - The input spectrum as obtained from an IRIS SG file. Should ; be a 1D array. ; Wavelength - The wavelength array. Should be a 1D array with as many ; elements as Inputspectrum. ; ; OPTIONAL INPUTS: ; ; KEYWORD PARAMETERS: ; TIME - Date and time of the observation. Should be supplied with ; DATE_OBS value from the IRIS SG file header. Format ; '2014-10-25T05:17:13.730'. Defaults to date and time when ; function is called. ; BINXY - Spatial binning factor with which the spectra were recorded. ; Defaults to 1. ; BINL - Wavelength binning factor with which the spectra were ; recorded. Defaults to 1. ; T_EXP - Exposure time in seconds. Defaults to 1. ; /A_EFF_ONLY - Return the spectrum corrected for effective area only (so no ; absolute radiometric calibration). Defaults to not set. ; /I_NU - Return the spectrum in frequency units, i.e., Hz^-1. Can be ; combined with /SI flag. Defaults to not set. ; /SI - Return the spectrum in SI units, W m^-2 s^-1 sr^-1 nm^-1. ; Can be combined with /I_NU flag, in which case the units ; will be W m^-2 s^-1 sr^-1 Hz^-1. Defaults to not set. ; /VERBOSE - Print out status messages. Defaults to not set. ; /DEBUG - Stop before returning from the function. Defaults to not ; set. ; ; OUTPUTS: ; 1D array with radiometric calibrated spectrum. ; ; OPTIONAL OUTPUTS: ; ; COMMON BLOCKS: ; ; SIDE EFFECTS: ; ; RESTRICTIONS: ; Requires SSWIDL and the following function: ; Functions: IRIS_GET_RESPONSE() ; ; PROCEDURE: ; ; EXAMPLE: ; calib_spectrum = IRIS_CALIB_SPECTRUM(Inputspectrum, Wavelength) ; ; MODIFICATION HISTORY: ; 2015 Mar Gregal Vissers: First version ; 2016 Nov GV: Extensive overhaul adding BINXY, BINL, I_NU and SI ; options. ; 2017 Oct A. Sainz Dalda: 'factor' keyword introduced to recover the ; calibration factor. ; 2019 May A. Sainz Dalda: 'dn2photon' keyword introduced to recover the ; dn2photon factor. ; 2019 June A. Sainz Dalda: 'Ephoton' keyword introduced to recover the ; Ephoton factor. ; $Id$ ;- ; FUNCTION IRIS_CALIB_SPECTRUM, Inputspectrum, Wavelength, TIME=time, $ A_EFF_ONLY=a_eff_only, VERBOSE=verbose, BINXY=binxy, BINL=binl, $ T_EXP=t_exp, I_NU=i_nu, DEBUG=debug, SI=si, $ factor = factor, dn2photon = dn2photon, Ephoton = Ephoton IF (N_PARAMS() LT 2) THEN BEGIN MESSAGE, 'Syntax: calib_spectrum = IRIS_CALIB_SPECTRUM(Inputspectrum, '+$ 'Wavelength [, TIME=time] [, BINXY=binxy] [, BINL=binl] [, T_EXP=texp] '+$ '[, /A_EFF_ONLY] [, /I_NU] [, /SI] [, /VERBOSE] [, /DEBUG])', /INFO RETURN,-1 ENDIF ; Process input keywords IF (N_ELEMENTS(TIME) EQ 1) THEN $ ;resp = IRIS_GET_RESPONSE(time, VERSION='003') $ resp = IRIS_GET_RESPONSE(time) $ ELSE $ ;resp = IRIS_GET_RESPONSE(VERSION='003') resp = IRIS_GET_RESPONSE() IF (N_ELEMENTS(BINXY) NE 1) THEN $ binxy = 1. IF (N_ELEMENTS(BINL) NE 1) THEN $ binl = 1. IF (N_ELEMENTS(T_EXP) NE 1) THEN $ t_exp = 1. ; Get necessary wavelength range nm = (MAX(Wavelength,/NAN) LT 1000) resp.lambda *= 10^(FLOAT(~KEYWORD_SET(NM))) wavelength_cm = Wavelength / 10^FLOAT(8-KEYWORD_SET(NM)) IF KEYWORD_SET(VERBOSE) THEN $ MESSAGE, 'Input wavelength range: '+STRTRIM(Wavelength[0],2)+'-'+$ STRTRIM(Wavelength[-1],2)+' '+(['A','nm'])[nm], /INFO lambda_avail_fuv = resp.lambda[WHERE(resp.area_sg[*,0] NE 0)] lambda_avail_nuv = resp.lambda[WHERE(resp.area_sg[*,1] NE 0)] ; Wavelength within FUV or NUV? idx = ((Wavelength[0] GE lambda_avail_nuv[0]) AND $ (Wavelength[-1] LE lambda_avail_nuv[-1])) cond_fuv = where((Wavelength lt max(lambda_avail_fuv) and Wavelength gt min(lambda_avail_fuv)) eq 1) cond_nuv = where((Wavelength lt max(lambda_avail_nuv) and Wavelength gt min(lambda_avail_nuv)) eq 1) print, 'Conditional values FUV, NUV...' , cond_fuv[0], cond_nuv[0] if cond_fuv[0] ne -1 and cond_nuv[0] eq -1 then idx = 0 if cond_fuv[0] eq -1 and cond_nuv[0] ne -1 then idx = 1 if cond_fuv[0] eq -1 and cond_nuv[0] eq -1 then begin print, 'Wavelength values are not available in the response calibration wavelength' stop endif IF KEYWORD_SET(VERBOSE) THEN $ MESSAGE, 'Using '+(['FUV','NUV'])[idx]+' response',/INFO a_eff_sel = INTERPOL(resp.area_sg[*,idx], resp.lambda, Wavelength) IF KEYWORD_SET(VERBOSE) THEN $ MESSAGE, 'Selected effective area statistics: (min,mean,max)=('+$ STRTRIM(MIN(a_eff_sel,/NAN),2)+','+$ STRTRIM(MEAN(a_eff_sel,/NAN),2)+','+$ STRTRIM(MAX(a_eff_sel,/NAN),2)+')',/INFO ; Alwasy divide by the effective area ;outputspectrum = Inputspectrum / a_eff_sel outputspectrum = Inputspectrum ;;;; / a_eff_sel Term included in FACTOR Mod. 20170613 ASD IF NOT KEYWORD_SET(A_EFF_ONLY) THEN BEGIN h = 6.62606885D-27 ; erg s c = 2.99792458D10 ; cm/s w_slit = !PI/(180.*3600.*3.) pix_xy = binxy * w_slit/2. CASE idx OF 0: BEGIN ; FUV1=1331.56-1358.40, FUV2=1390.00-1406.79 IF (Wavelength[-1] LT 1370.) THEN $ pix_l = 0.0129 $ ELSE $ pix_l = 0.0127 END 1: pix_l = 0.02546 ; Å/pix ENDCASE pix_l *= binl numerator = h * c / wavelength_cm * resp.dn2phot_sg[idx] ;denominator = a_eff_sel * pix_xy * pix_l * t_exp * w_slit denominator = a_eff_sel * pix_xy * pix_l * t_exp * w_slit ;;; a_eff_sel Term included in FACTOR Mod. 20170613 ASD ; print, a_eff_sel ;, pix_xy, pix_l, t_exp, w_slit ;, denominator ; print, a_eff_sel, pix_xy, pix_l, t_exp, w_slit ;, denominator factor = numerator / denominator dn2photon = resp.dn2phot_sg[idx] Ephoton = h * c / wavelength_cm ;outputspectrum *= factor ;IF KEYWORD_SET(I_NU) THEN outputspectrum *= Wavelength * Wavelength / 3.E18 ;IF KEYWORD_SET(SI) THEN outputspectrum *= 1.E-3 ; FACTOR Mod. 20170613 ASD IF KEYWORD_SET(I_NU) THEN factor *= Wavelength * Wavelength / 3.E18 IF KEYWORD_SET(SI) THEN factor *= 1.E-3 outputspectrum *= factor ; FACTOR Mod. 20170613 ASD IF KEYWORD_SET(VERBOSE) THEN $ MESSAGE, 'Spectrum converted by: (min,mean,max)=('+$ STRTRIM(MIN(factor,/NAN),2)+','+$ STRTRIM(MEAN(factor,/NAN),2)+','+$ STRTRIM(MAX(factor,/NAN),2)+')',/INFO ENDIF IF KEYWORD_SET(DEBUG) THEN STOP RETURN, outputspectrum END