S254 Data File Overview

The Campaigns

The RAW and DST data storage is organized by "campaign", which is essentially by beam time. We distinguish the following campaign identifiers:

Time Objective of Experiment Campaign Run Description

April 2002 Prop test with Zn beam test_apr02 Run List

March 2003 Production run with Au beam run_mar03 Run List

June-August 2003 Production run with Sn/La/Nd beam run_jun03 Run List

September 2003 Tests with Kr/Ar beam for Spaladin test_sep03 Run List

Time	Objective of Experiment	Campaign	Run Description
April 2002	Prop test with Zn beam	`test_apr02`	Run List
March 2003	Production run with Au beam	`run_mar03`	Run List
June-August 2003	Production run with Sn/La/Nd beam	`run_jun03`	Run List
September 2003	Tests with Kr/Ar beam for Spaladin	`test_sep03`	Run List

Raw Data Files

The raw data is stored in two forms:

Raw data: Data files as created by the DAQ system. They have the file type '.lmd'. These files can only be processed in a sequential fashion.
Rootified raw data: These files contain exactly the same event information as the original raw data files, but stored in ROOT container objects. The files are organized as a ROOT trees with branches holding different subevent types. This allows to access
- selectively any subevent class
- randomly any event of a file
The first property greatly improves the I/O efficiency when an analysis without the MUSIC data is done (which by far dominates the total data volume). The second property will allow to process small event selections in an efficient way.

All files are stored in the GSI mass storage system. Each file is stored under full name of the structure

    /archive/path/filename

Campaign	Raw Data path	Rootified raw data path
`run_mar03`	`/s254/run_mar03`	`/s254/gen/run_mar03/raw`
`run_jun03`	`/s254/run_jun03`	`/s254/gen/run_jun03/raw`
`test_sep03`	`/s254/test_sep03`	not yet available

The filename is

for raw data: run_####.lmd
for rootified raw data: run_####.root

with #### denoting the 4 digit run number (with leading zeros if needed).

Data Access

The details of how to access the various data generations are summarized in a separate document.

S254 Documentation

Last modified: Wed Oct 8 15:26:22 CEST 2003
Walter F.J. Müller