PSI μSR Facilities: Available Software and Data Storage

Background

Bulk μSR Data Format

The data files produced by the PSI μSR time-differential data acquisition programm are saved to a portable binary format (with extension ".bin" and 512 bytes/records and IEEE real-data format), called PSI-BIN. A description of the data format is given here.

Low-Energy μSR Data Format

The data files of LEM are written in an open file format called MusrROOT. This is much more flexible compared to the PSI-BIN format mentioned before. Eventually MusrROOT will replace PSI-BIN. A description of the MusrROOT file format can be found here.

Where to Find the Data Files?

The data-files are available from:
  • Bulk Data: the AFS PSI tree (at the subdirectory: /afs/psi.ch/project/bulkmusr/data/xxx/ where xxx represents the instrument name).
  • Bulk Data: the PSI-archive for older files (see information here).
  • LEM Data: the AFS PSI tree (at the subdirectory: /afs/psi.ch/project/nemu/data/his/ ).
Many programmes exist to analyze and manipulate these files (see list below -- note that some of these applications are no more supported).

Reading a Data File

Bulk μSR

A C++ class has been developed to read the μSR binary format produced at PSI with the td_bin format. It has been written as a hopefully easy to use and highly portable C++ code. A complete description of the class is provided here and the class can be downloaded here.

Low-Energy μSR

A complete description of a C++ class is provided here and the class can be downloaded from bitbucket.org.

Data Analysis

  • Analysis in time space—MUSRFIT: The programme musrfit has been developed by Andreas Suter and Bastian Wojek. It is a very versatile fitting software tool for analyzing time-differential μSR data. It is implemented in C++/ROOT and uses the MINUIT2 libraries developed at CERN for fitting data. User functions can also be defined. In addition simple Qt graphic user interfaces (musredit (Qt ≥ 4.6) / musrgui (Qt ≥ 3.3)) are available.
    • A user documentation for musrfit can be found here. This is an exported HTML of the musrfit wiki currently only accessible from within PSI.
    • A technical description for musrfit can be found here.
    • The source code is publicly available at bitbucket.org under https://bitbucket.org/muonspin/musrfit.
    • Starting from 2015 musrfit will only be maintained on the μSR Linux machine "musruser". This is the easiest and recommended way as this machine is also available from outside PSI and always provides the last version. The account to use is l_musr_tst and the password can be requested from one of the LMU staff members.
    • Alternatively, it is possible to perform some basic fitting using our online web application musrfit.cgi. This application uses musrfit to perform the fits. Instructions on how to use musrfit.cgi are available here.
  • Analysis in time space—WIMDA: This Windows based programme is developed and maintained by F. Pratt (ISIS). It can directly read PSI ".bin" data format.
    Details about WIMDA can be found here.

Data Conversion and Utilities

Since two types of data-formats are know available (see above), the users should optimize the use of the conversion programmes to their specific use.
  • Converting (basically) any format to any format:
    • Within the musrfit package a conversation tool is now available to convert basically from any µSR format into another. The tool is called any2many and can be invoked on the "musruser" machine or after installing locally musrfit.
    • Alternatively, you may use our web application SearchDB.cgi to search the LMU data base for specific runs, convert and download the corresponding data files in any format supported by any2many. Instructions on how to use SearchDB.cgi is available here.
  • Converting fixed-records binary PSI data-files (".bin"-format):
    • psibin2ascii
      • _Windows XP version:__This is available in the FTP-server from PSI (get PSIBIN2ASCII.EXE). Use _binary ftp transfer!
      • *_Linux:__ A Linux version is available in the AFS system at PSI. It can be run either from the Linux PSI cluster (llc) or from a stand-alone Linux workstation of PSI.
        Look here how to setup the software. The programme can be invoked by the command psibiascii .
    • psibin2origin
      • Windows XP version: This is available in the FTP-server from PSI (get PSIBIN2ORIGIN32.EXE ). Use binary ftp transfer!
      • Linux: A Linux version is vailable in the AFS system at PSI. It can be run either from the Linux PSI cluster (llc) or from a stand-alone Linux workstation of PSI.
        Look here how to setup the software. The programme can be invoked by the command psibin2origin .
  • Other utilities:
    • run_details -- A simple command-line application to display relevant information of a data file (support mdu and bin format)
      • For XP systems: see here for a download
      • For Linux at PSI: Look here how to setup the software. This application can be invoked by the command = run_details=.
    • NovelLook -- A new application based on Qt and Qwt to look at raw data and obtain asymmetry plots. Multiple histograms can be open simultaneously. The application is normally installed on the Linux systems for muSR users. Different versions are available
      • For XP systems with static libraries: see here for a download.
      • For Windows 7 64 bits systems with static libraries: see here for a download
      • For Linux systems with static libraries: see here for a download
      • This application is distributed under the terms of the GNU General Public License and its code is available here.
    • list_runs -- A utility programme to list header information from a range of runs.
      • Windows XP version: This is available in the FTP-server from PSI (get LIST_RUNS32.EXE).
      • Linux at PSI: Look here how to setup the software. The programme can be invoked by the command list_runs . It can be run either from the Linux PSI cluster (llc) or from a stand-alone Linux workstation of PSI.



Setting up Linux at PSI to run facility-software
  1. Copy the files "=.graphxrc=" and "=grap1=" from the directory /afs/psi.ch/user/m/musrmgr/
  2. Edit and modify the file grap1 for your needs.
  3. Edit your .bash_profile file or equivalent if on another shell. Add the following statement
    export PATH=$PATH:/afs/psi.ch/sys/i386_linux24/apps/graphx/bin:/afs/psi.ch/user/m/musrmgr/musr_software

    add also the line

    export PRINTER=XXXXXXX

    where XXXXXXX should be the CUPS name of your nearest printer.
    See
    here for a list of the available printer names.
  4. Logout and login again
  5. You can now run the available software by first invoking impenv graphx and after the available software.
  6. The on-line data are found in the following directory: /afs/psi.ch/project/bulkmusr/data/XXX/
    where you replace XXX by the name of the specific instrument
  7. Remember to use .bin data-file
  8. For minfit you must also set the environment variables MINFIT_NAME and MINFIT_DATA (i.e. export MINFIT_NAME...= and export MINFIT_DATA... )

-- Main.AlexAmato - 18 Sep 2013