Old MolPol DAQ Analysis

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Making Polarization measurements

Overview

  1. Start dbedit on adaq1, select "mollerpol_l" database and set in "beam_pol" configuration table in row "code" parameter "adcevents" from 9 to 2: " ... adcevents=2"
  2. Make at least two CODA runs in order to use both coil polarities.
  3. Data analysis:
    • old DAQ: adaq1:~/paw/moller/
      > paw
      paw> exec run run=15625
      paw> exec lg_spectra run=15625
      paw> exec time run=15625
      paw> lcd mag_optim
      paw> exec anpow_set e0=7.37 (E0 - beam energy in GeV)
      paw> exec asym11 anpow=0.7735 gate=0.033 run=15625 (gate=0.033 for 30Hz helicity frequency and gate=0.0008 for 1kHz)
    
    • It is possible to read these files from the ~moller home directory using any account defined in the adaqfs computer system

Executable Kumac's

Run.kumac

Terminology

PAW

  • PAW = "Physics Analysis Workstation", is an interpreted Fortran based language used in High Energy and Nuclear Physics data analysis.
  • PAW (User's Guide) is "PAW is an interactive utility for visualizing experimental data on a computer graphics display. It may be run in batch mode if desired for very large and time consuming data analyses; typically, however, the user will decide on an analysis procedure interactively before running a batch job." - which basically means it does the same kind of interpreted analysis work that ROOT does, except in Fortran instead of C++.
  • PAW was designed and used with Fortran and systems that had some hardware limitations, which is where a number of the anachronistic things like pre-reserved memory slots, postscript printing, and finite line-widths originated, and is why PAW has been largely replaced by ROOT in modern nuclear and particle physics applications.

KUIP

  • KUIP = "Kit for a User Interface Package", is the user interface designed to work with PAW. It is analogous to ROOT, and includes a command line interface (CLI) and GUI interfaces similar to ROOT's TBrowser and assorted histogram and canvas interfaces, and they operate similarly.
  • CERN user guide [1].
  • KUMACs are "KUIP Macros" and are interpreted PAW macro scripts that can be run in batch mode.

LUN/lun

  • LUN = "Logical Unit Number" - a lun is a METAFILE descriptor number ranging from 1 to 100.
  • From Brad Sawatsky's FAQ: "Some PAW commands ( HISTOGRAM/FILE, FORTRAN/FILE etc ...) have a parameter named lun. This parameter is a "logical unit number" on which are attached files. Some of these "logical unit number" are reserved by PAW and associated packages. The following table gives the list of the reserved units."
    • The table says 5-19 are reserved, and so are most of 81-91 and 97 - therefore most of the KUMACs discussed here start with lun 21.