Hinode/XRT response functions

XRT Response Functions: effect of new atomic data (Chianti ver. 10.0, released Nov-2020).

(5-Nov-2021, by Aki Takeda)
(19-Jan-2022, added notes about xrt_flux and xrt_teem.)
(5-Jan-2023, added added Ti_poly/Al_poly ratio curve as a NG pair.)

The XRT temperature response functions were recalculated, in response to the release of new Chianti atomic database version 10.0 in Nov-2020. The new atomic database (Chianti 10.0) turned out to make only negligible change on the XRT response functions calclated with the previous versions of Chianti(ver. 9.0.1).

quick review on the XRT temperature response basics.

1. The Response functions.

The solar spectra were calculated with the latest Chianti version 10.0, for 'coronal' (sun_coronal_1992_feldman_ext.abund), 'hybrid' (sun_coronal_2012_schmelz_ext.abund), and 'photospheric' (sun_photospheric_2015_scott.abund) abundances.

(a) solspec_ch1000_corona_chianti.genx
(b) solspec_ch1000_hybrid_chianti.genx
(c) solspec_ch1000_photos_chianti.genx

Below are the previous versions for comparison.

(d) solspec_ch901_corona_chianti.genx
(e) solspec_ch901_cr2012schmelz2_chianti.genx
(f) solspec_ch901_ph2011caffau_chianti.genx

Then I modified XRT_FLUX.PRO so that it can access the above spectrum files by setting the corresponding keyword. Examples of usage are as follows (including older versions).
IDL> flux_c = xrt_flux1000(logte, f1,f2, tim, /corona) IDL> flux_h = xrt_flux1000(logte, f1,f2, tim, /hybrid) IDL> flux_p = xrt_flux1000(logte, f1,f2, tim, /photos) IDL> flux_c9 = xrt_flux0901(logte, f1,f2, tim, /corona) IDL> flux_h9 = xrt_flux0901(logte, f1,f2, tim, /hybrid) IDL> flux_p9 = xrt_flux0901(logte, f1,f2, tim, /photos)

[NOTE] The more generalized function, XRT_FLUX_CH.PRO was developed to calculate the flux with the most recent solar spectral data. This function uses the most recent solar spectrum by default, and can also use the older versions by specifying in the keyword. See the program header about how to use (e.g., $SSW/hinode/xrt/idl/response/xrt_flux_ch.pro).

[ Example of calculating XRT response functions ]
For details, see the description of http://solar.physics.montana.edu/HINODE/XRT/xrt_ssw/xrt_flux1000.pro.

IDL> tim='1-may-2017 00:00'                ; change as needed.
IDL> f1=0 & f2=2                            ; for Open/Ti-poly 
IDL> logte = 5.+findgen(61)*0.05            ; prepare a temperature array
IDL> flux = xrt_flux1000(logte, f1,f2,  tim, /corona)

Below are the response functions of all the X-ray analysis filters available at XRT. It is known that the contamination accumulated on the CCD modifies the XRT response functions. As the amount of contamination varies with time, response functions are time-dependant. For the later convenience of analysis, the following response functions were calculated for the contamination level as of 12-Nov-2006.

(Click each plot to show details)

Al-poly/Open	thin-Be/Open	med-Be/Open	med-Al/Open

Open/Al-mesh	Open/thick-Al	Open/thick-Be	Al-poly/Ti-poly

Open/Ti-poly	C-poly/Open

2. The Filter Ratios.

These plots shows that the CHIANTI ver 10.0 database makes no significant difference in most filter ratio curves relative to those with version 9.0.1.

(click each plot to show detailed info)

Al-poly/Al-mesh	thin-Be/Al-mesh	thin-Be/Al-poly	med-Be/Al-poly

med-Al/Al-poly	med-Be/thin-Be	med-Al/thin-Be	med-Al/med-Be

thick-Be/med-Al	thick-Be/thick-Al	Ti-poly/Al-mesh	thick-Be/med-Be

Ti-poly/Al-poly

3. XRT_TEEM modification.

XRT_TEEM_CH1000.PRO was prepared.

Instead of directly modifying XRT_TEEM, I made a wrapper procedure that sets up the arrays of specified solar spectrum, and passes them to XRT_TEEM. You can get it from http://solar.physics.montana.edu/HINODE/XRT/xrt_ssw (or Ylstone:/disk/yla/software/xrt_ssw).

[Note 1] : Be sure to run with the latest version of XRT_TEEM and XRT_FLUX (both v2013-Nov-04), that includes new filter calibration (with CAL keyword). The version modified by Takeda after 2011 does not support this recalibration.
[Note 2] : If you download this procedure, do it together with the solar spectrum files listed in the above ('solspec_ch1000_corona_chianti.genx' is required at least). They are also found in the same directory.
[Note 3] : You might need to edit/change the path of the solar spectrum file directory(DIR_SPEC). They should eventuraly be sent to $SSW_XRT, but for now they are stored in /disk/yla/software/xrt_ssw/solar_spectrum, that is the current setting of DIR_SPEC defined at the begining of the procedure.

IDL> XRT_TEEM_CH1000, index1,data1,index2,data2,te,em, /corona
IDL> XRT_TEEM_CH1000, index1,data1,index2,data2,te,em, /hybrid
IDL> XRT_TEEM_CH1000, index1,data1,index2,data2,te,em, /photospheric
IDL> XRT_TEEM_CH1000, index1,data1,index2,data2,te,em, solar_spectrum='./solar_spectrum/solspec_ch1000_hybrid_chianti.genx'

[NOTE] The more generalized function, XRT_TEEM_CH.PRO was developed to calculate the flux with the most recent solar spectral data. This function uses the most recent solar spectrum by default, and can also use the older versions by specifying in the keyword. See the program header for how to use (e.g., $SSW/hinode/xrt/idl/response/xrt_teem_ch.pro).