;+ ; PROJECT: ; SDAC ; ; NAME: ; CALIBRATE ; ; PURPOSE: ; This subroutine calculates the energies corresponding to the channel ; boundaries for the BATSE Spectral Detectors. ; ; METHOD: ; The calibration is assumed ; to consist of two parts: a calculation of the light output from the NaI ; crystal from the channel number, and a calculation of the energy loss in ; the crystal that produces that light. The SLED is mitigated by an addition ; to the channel number in the term linear in channel number. The subroutine ; also calculates the effective uncompressed channel numbers. ; ; There are calibration fiducials for the lld's, those obtained by schwartz ; are the defaults. To change to the Preece fiducials, set which_fiducials ; to 0 in read_coef_com, spec_lld_old, which_fiducials ; ; INPUTS: ; ndet---the detector number ; width64---the variable width of the 64th channel ; spec_lld---LLD settings for all 8 detectors ; nlines---the number of lines used for calibration ; chan---vector of location of calibration lines in uncompressed channels ; en---vector of location of calibration lines in energy ; ; KEYWORD INPUTS: ; MAXCHAN - calibrate only up to this channel to save time. ; /discsp - edges are only those needed for discsp edges, lld/2, lld, max(evec) ; /report_calibration if set then the input arguments ; are set from the common block cal_sher_com and the outputs are ; calculated ; /noevec - don't compute the evec for output, just go as far as xvec ; ; Output: ; evec---the vector of energies, 257 values normally, 3 for /discsp ; unevec - energies w/o sled correction ; xvec---the vector of effective uncompressed channel boundaries ; pre_olight - vector of light outputs/channel before sled amp correction ; olight - vector of light outputs/channel after sled ; ; Common blocks: ; common spline_com, break,c0,c1,c2,c3 ; common sled_com, sb,sc,sd,scut ; common fiducial_com,af,bf,cf,xf ; common read_coef_com, spec_lld_old, which_fiducials ; ;common block for passing 511 line position out to the top level ; common cal_sher_com, pass511, w64_used, spec_lld_used ; ; Category: CGRO/BATSE ; ; Calls: ; READ_COEF, SLED, EDGE_PRODUCTS, FCRYSTAL, DELTA_CONTROL, FCHECK ; GAIN_COR, CHANNELS, LLD_CHAN ; History: ; Written 10/2/91 DLB; Revised 12/6/91 laf; Last modified 4/7/92 DLB ; Translated to IDL by RAS, 92/6/5 ; ; ras, 13-March-94, fixed discsp settings ; ras, 19-aug-94, default fiducials for lld changed to ras's ; ras, 19-oct-94, corrected energy calibration for spec discriminators, discsp ; ras, 29-mar-95, added cal_sher_com and communication for this common block ; ras, 29-dec-95, include sled correction in DISCSP calculation since ; the 511 line is in the pha calibration which includes the ; sled pedestal which can be several channels wide ; also switched to Preece's lld calibrations as default ; Version 2, ras, 15-March-1996, added maxchan ; Version 3, ras, 8-Nov-1996, changed fiducial in Schwartz calibration for ; det 2. ; Version 4, ras, 11-Nov-1996, changed defaults to Schwartz fiducials ; Version 5, ras, 27-nov-1996, calling LLD_CHAN for Skelton fiducial calibration ; and using DATE for discsp_edges because of SPEC1 change on 3-Oct-1993 ; Version 6, richard.schwartz@gsfc.nasa.gov, ; added SPEC_LLD keyword to LLD_CHAN call 1-apr-1998. ; ; ;- ; pro calibrate, ndet, width64, spec_lld, nlines, chan, en, evec, xvec, $ pre_olight=pre_olight, olight=olight, unevec=unevec, discsp=discsp,$ report_calibration=report_calibration, noevec=noevec, $ maxchan=maxchan, error=error, date=date error = 1 ;common block for passing 511 line position, width of channel 64, and ;the spec lower-level discriminator settings out to the top level. ;This facilitates adjusting the calibration in the top-level routines. common cal_sher_com, ndet_used, chan_used, en_used, w64_used, spec_lld_used common sled_com, sb,sc,sd,scut common fiducial_com,af,bf,cf,xf common read_coef_com, spec_lld_old if keyword_set(report_calibration) then begin if n_elements(ndet_used) eq 0 then return ndet = ndet_used chan = chan_used nlines = n_elements(chan) en = en_used width64 = w64_used spec_lld=spec_lld_used endif ; ; Read in coefficients if the first time through checkvar,spec_lld_old, intarr(8) new = where( spec_lld eq spec_lld_old, ncount) if total(abs(spec_lld-spec_lld_old)) ne 0 then begin read_coef,spec_lld spec_lld_old=spec_lld endif ; ; Set up an array of channel boundaries channel,width64,xvec if keyword_set(noevec) then return ;Make the routine more tolerant of non-vector arguments for the cal line chan = fltarr(nlines) + chan en = fltarr(nlines) + en ; ; Get gain corrected coefficients gain_cor,ndet,nlines,chan,en,a,b,c,x_0 ; ; Loop over all channel boundaries ; First calculate the light from the NaI crystal olight = a+b*xvec iless = where(xvec lt x_0, ncount) if ncount ge 1 then $ olight(iless)=olight(iless)+c*(xvec(iless)-x_0)^2 pre_olight = olight ;olight prior to sled correction ; ; Make correction for SLED sled,ndet,b,xvec,olight ; Finally, calculate the energy evec = olight(0:fcheck(maxchan,256))*0.0 unevec = evec case keyword_set(discsp) of 0: begin if fcheck(maxchan,256) gt 100 then begin for i=0,n_elements(evec)-1 do begin evec(i) = fcrystal(olight(i)) unevec(i) = fcrystal(pre_olight(i)) endfor endif else begin ;Use fast interpolation scheme!!! evec = fcrystal1(olight) unevec = fcrystal1(pre_olight) endelse end 1: begin ;3 values for discsp fratio = (fast_ratio(spec_lld))(ndet) nval = [lld_chan( date, ndet, spec_lld=spec_lld, /skelton), n_elements(evec)-1] ;Something happened to SPEC1 during reboost on 3-Oct-1993 that changed ;the slld->lld_chan conversion if ndet eq 1 then if anytim(fcheck(date,0.0),/sec) gt anytim('3-oct-1993',/sec) then $ nval(0)=nval(0)-4 nval = [nval(0)/2,nval] ; > 0.01 evec = evec(nval) evec(2) = fcrystal(pre_olight(nval(2))) olight1 = a + b*nval(1) if nval(1) lt x_0 then olight1 = olight1 + c*(nval(1)-x_0)^2 if olight1 le 0 then printx,'Danger in DISCSP calibration!!! Calibrate.pro' pre_olight1=olight1 sled, ndet, b, nval(1), olight1 unevec(1) = fcrystal(pre_olight1) unevec(0) = fcrystal(pre_olight1/fratio) evec(1) = fcrystal(olight1) evec(0) = fcrystal(olight1/fratio) ;print, 'olight1, evec(0:2)', olight1, evec(0:2) end endcase ;if delta_control is set to 0, then the pha energy widths are in energy loss units ;which is the bdas analysis standard, the spex default is to use the light widths if not delta_control() then begin olight = evec if fcheck(ndet,1) eq 0 and not keyword_set(discsp) then $ printx,'Channel widths set to Energy loss units, BDAS standard.' endif else if fcheck(ndet,1) eq 0 and not keyword_set(discsp) then $ printx,'Channel widths set to PHA widths, SPEX SHERB standard.' ;save the current arguments in common to be able to report them ndet_used = ndet en_used = en chan_used = chan w64_used = width64 spec_lld_used = spec_lld error=0 end