This page was created by the IDL library routine
mk_html_help2.
Last modified: Thu Aug 6 12:53:14 2020.
PROCEDURE:
thm_load_esa_bkg
PURPOSE:
Adds background count rates to the ESA data structures which can be used
by thm_pei_bkg_sub and thm_pee_bkg_sub for background removal.
INPUT:
probe: strarr themis spacecraft - "a", "b", "c", "d", "e"
if not set defaults to all
sc: strarr themis spacecraft - "a", "b", "c", "d", "e"
if not set defaults to all
datatype: string array specifying datatypes from which background is calculated
valid inputs: "peir", "peer", "pser"
if not set defaults to all
peer data is also used for calculating pser background
trange: two element time range
if not specified or set with timespan user will be prompted
user_select: 0/1 keyword not working -- code under construction
if set, will run thm_pse_bkg_set.pro to let the user select the interval for calculating pser sunlight background
if not set, will run thm_pse_bkg_auto.pro for automated pser sunlight background subtraction
CREATED BY: J. McFadden 08/12/31
VERSION: 1
LAST MODIFICATION: 08/12/31
MOD HISTORY:
08/12/31
10/03/18 added peer background from scattered electrons
10/04/06 background array for electrons now filled using ion calculated background
2016/06/30 minor changes to integrate with spedas
2016/07/12 autoload all data, some code cleaning
NOTES:
Autoloads pser, peir, peer, and state data if not present
If both iesa and sst data sets are used, will use the lower background estimate
Uses iesa data for background in the inner magnetosphere
Will only work properly if data includes a perigee pass
(See projects/themis/spacecraft/particles/ESA/background/thm_load_esa_bkg.pro)
PROCEDURE: thm_load_pei_bkg PURPOSE: Adds background count rates to the ESA structures for use by thm_pei_bkg_sub INPUT: KEYWORDS: probe: strarr themis spacecraft - "a", "b", "c", "d", "e" if not set defaults to all sc: strarr themis spacecraft - "a", "b", "c", "d", "e" if not set defaults to all themishome: string path to data dir, where data dir contains the th* dir, where *=a,b,c,d,e datatype string or 0/1 if not set, uses both pser and peir data if set to pser, uses pser only if set to peir, uses peir only user_select 0/1 if set, will let the user selected interval for pser sunlight background assumes that thm_pse_bkg_set.pro has been run if not set, will run thm_pse_bkg_auto.pro for automated background subtraction CREATED BY: J. McFadden 08/12/31 VERSION: 1 LAST MODIFICATION: 08/12/31 MOD HISTORY: 08/12/31 10/03/18 added peer background from scattered electrons NOTES: Assumes pser data is loaded if pser data to be used for background pser data is only used for times when the attenuators are closed Assumes esa data is loaded If both esa and sst data sets are used, will use the lower background estimate Will only work properly if data includes a perigee pass
(See projects/themis/spacecraft/particles/ESA/background/thm_load_pei_bkg.pro)
FUNCTION: thm_pee_bkg(dat) INPUT: dat: data structure (n,3) vector arrays dimension (n,3) or (3) PURPOSE: returns estimates of background determined from lowest counts in dat.data angle averaged array CREATED BY: J.McFadden 10-04-06 Modifications J.McFadden 10-04-06 aflores 2016-06-30 minor changes to integrate with spedas
(See projects/themis/spacecraft/particles/ESA/background/thm_pee_bkg.pro)
FUNCTION: thm_pee_bkg_sub(dat,bkg=bkg) PURPOSE: calculates secondary background from primary. Returns data structure with secondaries, photo-e, and Bremsstrahlung (dat.bkg) subtracted INPUT: dat: themis pee data structure KEYWORDS: Assumptions Secondary electron spectral shape determined from a fit to TH-B on 08-03-05 in shadow (see first results paper) Secondary spectra for this day fits ~ 1./(1.+(E/5.4)^3), where E is the secondary energy sec ~ 1./(1.+(E/5.4)^3) 5.4 was determined empirically from the fit CREATED BY: J.McFadden 09-11-18 Modifications J.McFadden 10-04-06 Changed to allow dat2.bkg subtraction of Bremstrahlung X-rays and seconda aflores 2016-06-30 minor changes to integrate with spedas
(See projects/themis/spacecraft/particles/ESA/background/thm_pee_bkg_sub.pro)
FUNCTION: thm_pei_bkg(dat) INPUT: dat: data structure (n,3) vector arrays dimension (n,3) or (3) PURPOSE: returns estimates of background determined from lowest counts in dat.data angle averaged array CREATED BY: J.McFadden 08-12-31 Modifications J.McFadden 08-12-31 aflores 2016-06-30 minor changes to integrate with spedas
(See projects/themis/spacecraft/particles/ESA/background/thm_pei_bkg.pro)
FUNCTION: thm_pei_bkg_sub(dat,bkg=bkg) PURPOSE: returns data structure with background subtracted, assumes dat.bkg in data structure, run thm_load_esa_bkg.pro first INPUT: dat: themis pei data structure KEYWORDS: bkg: flt if set, uses this value in background subtraction Assumptions Program assumes no energy dependence for contamination Program assumes dat.bkg is already computed dat.bkg is added to structure by thm_load_esa_bkg.pro CREATED BY: J.McFadden 08-12-29 Modifications Mcfadden 09-01-09 added relative bkg dependence as a function of anode mcfadden 09-01-30 changed dat.bkg to an array aflores 2016-06-30 minor changes to integrate with spedas
(See projects/themis/spacecraft/particles/ESA/background/thm_pei_bkg_sub.pro)
PROCEDURE: thm_pse_bkg_auto,sc=sc,t1=t1,t2=t2 INPUT: PURPOSE: Generates 'th'+sc+'_pser_minus_bkg' for use by thm_load_esa_bkg.pro -- Auto selects time interval for pser background subtract CREATED BY: J.McFadden 09-01-01 Modifications J.McFadden 09-02-05 modified to work with both attenuator on and off J.McFadden 09-04-15 modified to include correct calibrations J.McFadden 09-09-16 modified to include modes with psef w/ spin resolution and pser w/o spin resolution aflores 2016-06-30 minor changes to integrate with spedas Assumptions SST data is already loaded Uses pser data only - assumes it is the highest time resolution
(See projects/themis/spacecraft/particles/ESA/background/thm_pse_bkg_auto.pro)
PROCEDURE: thm_psi_bkg_set,sc=sc,tt_on=tt_on,tt_off=tt_off INPUT: PURPOSE: User selects time interval for determining ion sst background counts, use fast survey if available CREATED BY: J.McFadden 10-04-25 Modifications J.McFadden Assumptions Needs corrections for different detector gf for psir6
(See projects/themis/spacecraft/particles/ESA/background/thm_psi_bkg_set.pro)
FUNCTION: thm_psi_bkg_sub(dat) INPUT: dat: data structure (n,3) vector arrays dimension (n,3) or (3) PURPOSE: returns psi data structure with background subtracted, run thm_psi_bkg_set.pro first Assumptions Assumes thm_psi_bkg_set.pro has been run Assumes input distribution is in counts Output distribution will have no negative numbers CREATED BY: J.McFadden 08-12-30 Modifications mcfadden 09-02-03 modified to work for both atten on and off
(See projects/themis/spacecraft/particles/ESA/background/thm_psi_bkg_sub.pro)