RHESSI Detector Resolution

Resolution is the sum of a constant term (electronic resolution), a term proportional to the square root of energy (natural statistics of germanium electron/hole pairs), and a term proportional to energy (trapping). 

resolution(E) = sqrt ( A^2. + (B*sqrt(E))^2. + (C*E)^2. )

The values of A, B, and C for each detector segment are read from a table of parameters vs dates (hessi_resol_vs_time.1000) and interpolated to the requested date.  The units of the resolution are FHWM in keV of a gaussian line.

The following plots show the calculated RHESSI detector FWHM resolution as a function of both time and energy.  These are the resolutions used in calculating the spectral response matrix in the RHESSI software.

For questions about the RHESSI Detectors, please contact David Smith.



Front Segments at:   start of mission    2008    2016
Rear Segments at:    start of mission    2008    2016
Front Segment history at:    10 keV   150 keV
Rear Segment history at:   200 keV    15 MeV

Front Segments in 2002

IDL COMMAND:   hsi_plot_resolutions,time='20-feb-2002',xstyle=1, /png,filename='res_2002_front.png'


Front Segments in 2008

IDL COMMAND:  hsi_plot_resolutions,time='1-oct-2008',xstyle=1, /png,filename='res_2008_front.png'


Front Segments in 2016

IDL COMMAND:  hsi_plot_resolutions,time='1-jan-2016',xstyle=1, /png,filename='res_2016_front.png'


Rear Segments in 2002

IDL COMMAND:  hsi_plot_resolutions,/rear,xstyle=1, time='20-feb-2002', energy=findgen(1001)*20.+200, /png,filename='res_2002_rear.png'


Rear Segments in 2008

IDL COMMAND:  hsi_plot_resolutions,/rear,xstyle=1, time='1-Oct-2008', energy=findgen(1001)*20.+200, /png,filename='res_2008_rear.png'


Rear Segments in 2016

IDL COMMAND:  hsi_plot_resolutions,/rear,xstyle=1, time='1-jan-2016', energy=findgen(1001)*20.+200, /png,filename='res_2016_rear.png'


Front Segment history at 10 keV

IDL COMMAND:  hsi_plot_res_history,energy=10,ystyle=1,xstyle=1,/png,filename='res_history_10keV_front.png'

smaller y range


Front Segment history at 150 keV

IDL COMMAND:  hsi_plot_res_history,energy=150,ystyle=1,xstyle=1,/png,filename='res_history_150keV_front.png'

smaller y range:


Rear Segment history at 200 keV

IDL COMMAND:  hsi_plot_res_history,energy=200,/rear,xstyle=1,/png,filename='res_history_200keV_rear.png'

smaller y range:


Rear Segment history at 15 MeV

IDL COMMAND:  hsi_plot_res_history,energy=15000,/rear,xstyle=1,/png,filename='res_history_15000keV_rear.png'

smaller y range:



Last edited 04 January 2016 by Kim Tolbert