XRT Response Functions: effect of new atomic data (Chianti ver. 7.1.3) and new filter calibration (Nov-2013).

(27-Feb-2014, by Aki Takeda)

The XRT response functions were recalculated, according to the following two events that would affect the XRTresponses.

The update of atomic database in Chianti 7.1.3 turned out to make only negligible change on the XRT response functions calclated with the previous versions of Chianti(ver. 7.1 and ver. 6.0.1). On the contrary, the new calibration of the thick filters gives 10-50% smaller response to the med-Al, med-Be, thick-Al, and thick-Be filters, and effects corresponding filter ratio functions to give higher temperature values than the previous result.

back to my initial version of XRT response function page

1. The Response functions.

The solar spectra were calculated with the latest Chianti version 7.1.3, for 'coronal', 'hybrid', and 'photospheric' abundances. Then I modified XRT_FLUX.PRO so that it can access the above spectrum files by setting the corresponding keyword.

IDL> flux_c = xrt_flux601(logte, f1,f2, tim, /corona)
IDL> flux_h = xrt_flux601(logte, f1,f2, tim, /hybrid)
IDL> flux_p = xrt_flux601(logte, f1,f2, tim, /photos)
IDL> flux_c7 = xrt_flux713(logte, f1,f2, tim, /corona)
IDL> flux_h7 = xrt_flux713(logte, f1,f2, tim, /hybrid)
IDL> flux_p7 = xrt_flux713(logte, f1,f2, tim, /photos)
IDL> flux_cal1 = xrt_flux713(logte, f1,f2, tim, /corona, cal=1) ; old calibration

[ Example of calculating XRT response functions ]
For details, see the description of Mithra:/www/HINODE/XRT/xrt_ssw/xrt_flux713.pro.

IDL> tim='15-sep-2010 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_flux713(logte, f1,f2,  tim, /corona)

Below are the response functions of all the X-ray analysis filters available at XRT. The calibration data released on 20-Aug-2010 was used. 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.
Plots are clickable (i.e., click each plot to show more detailed info).

Al-poly/OpenC-poly/Openthin-Be/Open med-Be/Openmed-Al/Open
Open/Al-mesh Open/Ti-polyOpen/thick-Al Open/thick-BeAl-poly/Ti-poly

2. The Filter Ratios.

These plots shows that the Chianti ver 7.1.3 makes no sigificant difference in the filter ratio curves relative to those with version 6.0.1. On the other hand, recalibrated thick filters results in significant change in ratio curves (e.g., thick-Be/med-Al, thick-Be/thick-Al). Again, plots are clickable (i.e., click each plot to show more detailed info).

C-poly/Al-polythin-Be/Al-polymed-Be/Al-poly med-Al/Al-polythin-Be/C-poly
med-Be/C-polymed-Al/C-polymed-Be/thin-Be med-Al/thin-Bemed-Al/med-Be
Al-poly/Al-meshTi-poly/Al-meshmed-Al/Ti-poly thick-Be/med-AlTi-poly/Al-poly
thin-Be/Al-meshthin-Be/Ti-polythick-Be/thick-Al thick-Al/Ti-poly

3. XRT_TEEM modification.

New calibration of XRT thick filters are already included in the latest version of XRT_TEEM (ver 2013-Nov-04, by N. Narukage). Therefore, my goal is to add elementary abundance variation to the latest XRT_TEEM.


Calculate solar spectrum files with different abuncances available in Chianti database ver. 7.1.3. These files are found in this directory. Detailed information is available in the text section of each genx file:
IDL> restgen,file='./solspec_ch713_corona_chianti.genx',text=text & print,text
Solar specta (photon number) calculated with Chianti ver.7.1.3
 for isothermal plasma with electron density : 1.0e9 cm^(-3)
 Intensity unit : photons cm^3 s^-1 sr^-1 * EM,   
 EM : unit column EM,  1. cm^-5. 
 Abundance : sun_coronal_1992_feldman_ext.abund  
 Ioneq : chianti.ioneq  
 24-Feb-2014 (AkT).

IDL> restgen,file='./solspec_ch713_hybrid_chianti.genx',text=text & print,text
Solar specta (photon number) calculated with Chianti ver.7.1.3
 for isothermal plasma with electron density : 1.0e9 cm^(-3)
 Intensity unit : photons cm^3 s^-1 sr^-1 * EM, 
 EM : unit column EM,  1. cm^-5.   
 Abundance : sun_coronal_1999_fludra_ext.abund
 Ioneq : chianti.ioneq  
 24-Feb-2014 (AkT).

IDL> restgen,file='./solspec_ch713_photos_chianti.genx',text=text & print,text
Solar specta (photon number) calculated with Chianti ver.7.1.3
 for isothermal plasma with electron density : 1.0e9 cm^(-3)
 Intensity unit : photons cm^3 s^-1 sr^-1 * EM, 
 EM : unit column EM,  1. cm^-5. 
 Abundance : sun_photospheric_2007_grevesse.abund  
 Ioneq : chianti.ioneq
 24-Feb-2014 (AkT).

IDL> restgen,file='./solspec_ch713_ph2011caf_chianti.genx',text=text & print,text
Solar specta (photon number) calculated with Chianti ver.7.1.3
 for isothermal plasma with electron density : 1.0e9 cm^(-3)
 Intensity unit : photons cm^3 s^-1 sr^-1 * EM, 
 EM : unit column EM,  1. cm^-5. 
 Abundance : sun_photospheric_2011_caffau.abund  
 Ioneq : chianti.ioneq
 24-Feb-2014 (AkT).

IDL> restgen,file='./solspec_ch713_cr2012schmelz_chianti.genx',text=text & print,text
Solar specta (photon number) calculated with Chianti ver.7.1.3
 for isothermal plasma with electron density : 1.0e9 cm^(-3)
 Intensity unit : photons cm^3 s^-1 sr^-1 * EM,   
 EM : unit column EM,  1. cm^-5. 
 Abundance : sun_coronal_2012_schmelz.abund  
 Ioneq : chianti.ioneq  
 24-Feb-2014 (AkT).
XRT_TEEM_CH713.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 Mithra:/www/HINODE/XRT/xrt_ssw (or Ylstone:/disk/yla/software/xrt_ssw).
IDL> XRT_TEEM_CH713, index1,data1,index2,data2,te,em, /corona
IDL> XRT_TEEM_CH713, index1,data1,index2,data2,te,em, /hybrid
IDL> XRT_TEEM_CH713, index1,data1,index2,data2,te,em, /photospheric
IDL> XRT_TEEM_CH713, index1,data1,index2,data2,te,em, solar_spectrum='./solar_spectrum/solspec_ch713_cr2012schmelz_chianti.genx'

4. Newly introduced abundances.

A few of new photosperic abundance sets are newly introduced since the Chianti ver. 7.1.3. For comparison, I calculated the following two sets.