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) program checks and sorts data with respect to the values in the first
column.
Inserting data from calibration spectrum
Inserting energy from nuclide library
Inserting and editing of calibration data
Inserting data from calibration spectrum
10.4.2
To automate process of calibration data input, you have to use the ROI table and
a nuclide library, which contains descriptions of those nuclides, which are present
in a standard of calibration. The rule of operation is the following:
Make a measurement of the calibration spectrum,
Choosing calibration lines and set them as
ROI regions
. It could be
done by hand or automatically (ie. in the module ANALYZIS run
Automatic
peak search
with fitting peaks),
Switch to
Calibration module
and make a calibration spectrum with
ROIs visible in a spectrum panel,
Run operation
:
icon:
menu: Calibration | ROI from spectr.
Calibration operations
: ROI from spectr.
This operation automatically fills
data table
using following parameters from
ROIs: positions of centroid to column
, FWHM values to column
and
netto areas to column
.
Column
will be filled after operation Data from library
(see
Inserting
energy from nuclide library
)
Values in column
will be filled after Calc. efficiency operation (see
Detection efficiency calculate
)
Every row entered to the calibration data table is marked on the diagram of the
calibration curve what gives the user additional control of input data correctness.
Energy calibration process
Peak shape calibration process
Efficiency calibration process
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Inserting energy from nuclide library
10.4.3
Execute Data from library command and turn to the dialog box where you may
input energy values.
If all peaks are well defined and their count and positions correspond to the
values in a library of calibration standard, then energy values for individual peaks
can be flowed automatically from that library by of opening Calibration data editor
dialog box:
Copying energy values from nuclides library:
In Calibration data editor dialog box additional table is opened with a button
marked with "left arrow" sign. The right table contains data taken from the nuclide
library. First, select with the mouse or keyboard an appropriate row in the table of
calibration data (left one), then in the library table select the correct row
containing data for selected nuclide. Pressing the button with arrow sign, copies
the value of energy for selected nuclide to calibration data table.
All data copied automatically can be edited. If the result of the peak search
command is not satisfactory, you may return to ANALYSIS module, and modify
selected boundaries of ROI and perform peak fitting operation for each ROI
independently (to properly define peak position) and later return to
CALIBRATION module, delete calibration data and execute ROI from spectrum
command.
Energy calibration process
Calibration curve
Setting calibration to spectrum
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Calibration
Calibration – general principles
10.5
Energy calibration process
Energy calibration
Inserting and editing of calibration data
Fitting of the energy depends on channel number and is done using polynomial
function specified in Calculate_calibration_equation_coefficients_menu:_Calibration_|_Calculate_context_menu_of_calibration_panel:_Calculate'>Polynomial degree box.
Calculate calibration equation coefficients
menu: Calibration | Calculate
context menu of calibration panel: Calculate
After invoking Calculate, command, the program verifies whether the table of
calibration data is complete and whether the number of rows in the table is
enough to fit the polynomial of required degree – if it is not then the message is
displayed on screen:
„Not enough data! Calibration can not be done."
After performing calculations, the equation coefficients values are displayed on
screen with errors and calibration curve.
In case when a curve does not fit calibration data properly, then operation may
be repeated with different polynomial degree.
Calibration data
Calibration curve
Setting calibration to spectrum
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10.6
Peak shape calibration process
Peak shape calibration
There are two ways of invoking process of peak shape calibration:
• from calibration panel: - mouse click on tab Peak shape calibration
• from menu Calibration | Peak shape calibration
Peak shape calibration should be performed in the same way as energy
calibration described earlier.
During loading energy calibration data from the ROI table, the calibration data
table is filled automatically, therefore, to perform this calibration, select type and
equation degree and later execute Calculate command.
Calibration – general principles
10.7
Efficiency calibration process
Efficiency calibration
There are two ways of invoking process of efficiency calibration:
• from calibration panel: - click on tab Efficiency calibration
• from menu Calibration | Efficiency calibration
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