How to start ?

First make sure that the following lines are added to your login file (.login for the csh):

setup coda
setenv HALLA_DIR  /work/halla/software
setenv HALLA_SRC  $HALLA_DIR/src
setenv HALLA_BIN  $HALLA_DIR/`uname`/bin
setenv HALLA_LIB  $HALLA_DIR/`uname`/lib
setenv PATH .:${HALLA_BIN}:${PATH}

If you want to have your own version of the analysis software, follow the steps described in the document:

http://www.cebaf.gov/Hall-A/data_reduc/calibrations/quick_install.html

To start a scanning session give the command espace or espace -m to get the X-window equivalent version. The prompt espace > has appeared now and commands can be typed in.

Before explaining the program in detail, an example is shown of how to analyze a 12C(e,e') run. Below is listed the contents of a macro file for the KUIP interface (known as KUMAC file). Instead of typing in each command, one can create a macro file containing all commands and then execute this file by giving in ESPACE the command exec file_name.

*
********************** define FILES ***********************
*
set/file/output test.hbook
set/file/database db_eh
set/file/header hdr_12Cee.prm
*
********************** define CUTS ************************
*
define/cut/1d spec_e.th_tg-1 -0.08  0.08
define/cut/1d spec_e.ph_tg-1 -0.11  0.11
define/cut/1d spec_e.p_kin-1 596.0 600.0
define/cut/1d spec_e.cer.adc-1 0.0 150.0
define/logical accepte spec_e.th_tg-1&&spec_e.ph_tg-1
*
********************* spectrometer E *******************
*
set/hitbits (+spec_e.s1)
set/auto_window on
set/spectrum/bins/x1 1
spectra/save spec_e.s2.hp_r
spectra/save spec_e.s1.hp_r
spectra/save spec_e.s1.adc_r,spec_e.s1.adc_l, _
              spec_e.s2.adc_r,spec_e.s2.adc_l accepte
set/spectrum/bins/x1 50
set/spectrum/bins/x2 50
spectra/save spec_e.s1.adc_r/spec_e.s2.adc_r accepte
spectra/save spec_e.s1.adc_l/spec_e.s2.adc_l accepte
set/auto_window off
set/spectrum/bins/x1 10
set/spectrum/window/x1 0.0 8000.0
spectra/save spec_e.cer.adc
set/spectrum/bins/x1 300
set/spectrum/window/x1 -0.15 0.15
spectra/save spec_e.th_tg-1,spec_e.ph_tg-1 accepte&&spec_e.p_kin-1
set/spectrum/bins/x1 250
set/spectrum/window/x1 -0.025 0.025
spectra/save spec_e.y_tg-1
set/spectrum/bins/x1 500
set/spectrum/window/x1 575.0 605.0
spectra/save spec_e.p_kin-1 accepte
set/hitbits (+spec_e.cer,+spec_e.s1)
spectra/save spec_e.p_kin-2 !spec_e.cer.adc-1&&accepte
set/spectrum/window/x1 -0.05 0.15
spectra/save spec_e.dp_kin-1 accepte
set/spectrum/window/x1 -0.7 0.7
spectra/save spec_e.x_rot_kin-1 accepte
*
********************* scanning and output *****************
*
file/scan /scratch1/offerman/run_941203024856 1 10000
spectra/write
quit

In the first few lines the names of the histogram, database and header file are given. The database contains constants of the spectrometer and detector package, like spectrometer tracing tensors and wire positions in the VDC's. The header file contains information specific for the data run to be analyzed, like target material and spectrometer field settings.

The next lines contain the definition of cuts on variables as read out from the detector package by the data acquisition code CODA , like the ADC value of the gas Cerenkov in the electron spectrometer (spec_e.cer.ecer) or variables derived from CODA information, like the reconstructed spectrometer angles theta_tg and phi_tg. Two of these logical definitions are combined by anding (&&) them into a new one called accepte defining the solid-angle acceptance of the electron spectrometer.

In the next part the histograms are defined through save commands of variables. Some of these save's are performed under the condition that a logical is true. (Compare spectra/save spec_e.y_tg-1 and spectra/save spec_e.p_kin-1 accepte). The variables are referred to through a tree-like structure. For example the spec_e.s1.adc_l string points to the ADC value of the left channel of the S1 scintillator of the electron spectrometer, spec_e.y_tg points the reconstructed y-coordinate at the target of the electron spectrometer. The next section shows which variables specific to a certain spectrometer detector or just spectrometer can be accessed.