Target Conditions
Target History
The purpose of this page is to record the history of the target conditions for the GlueX experiment. Every time that the target is changed or moved, the table below must be updated with four pieces of information
- What target is installed. An integer corresponding to the target type table in Target Types must be used.
- The z position in the GlueX coordinate system in units of cm.
- The data and time that the target was modified
- Who recorded this information
| Target Type Index | Target Position (in z, cm) | Inserted Date/Time | Removed Date/Time | Recorded By |
|---|---|---|---|---|
| 0 | 65 cm | 2014-10-10 | 2014-10-28 15:08 | Alexandre Deur |
| 3 | 65 cm | 2014-10-28 15:08 | 2014-11-07 05:00 | Alexandre Deur |
| 7 | 65 cm | 2014-11-07 05:00 | 2014-11-11 11:00 | Elton Smith |
| 3 | 65 cm | 2014-11-11 11:00 | 2015-02-06 12:00 (est.) | Alexandre Deur |
| 1* | 65 cm | 2015-02-06 12:00 (est.) | current | Sean Dobbs |
- The 10 cm CH2 target was mounted on the nose of the Start Counter for the Spring 2015 run.
Target Types
This table describes which target types correspond to which target index number. The canonical source of this information is the CCDB table /TARGET/target_type_list
| Index | Description |
|---|---|
| 0 | no target |
| 1 | 30 cm LH2 |
| 2 | 2mm CH2 |
| 3 | 10 mm CH2 |
| 4 | CH2 cup (2mm/7mm) |
| 5 | 3.4 mm graphite |
| 6 | Al. cross |
| 7 | Al. cylinder w/ triangle hole |
| 8 | |
| 9 | |
| 10 |
Updating the CCDB
The CCDB stores the target type and position for use in simulation and reconstruction software. A convenient script can be used to update the CCDB, which can be found at
/home/sdobbs/Calibrations/target/update_target_info.py
Users must be part of the "halld" user group to update the CCDB.
To update the target conditions in the CCDB, pass the target type and position (in cm), for example
update_target_info.py 2 68.
The current list of target types can be obtained using the -P option
update_target_info.py -P
The -h option will print some help on the command line.
Updating the mapping between target indices and types (/TARGET/target_type_list) should only be done in consultation with software experts (S. Dobbs and M. Ito).
