Operating the Fiber Start (Pion Hodoscope)

If anything strange is happening, dont hesitate to call/wake me up.
My telephone number in GSI guesthouse is: XXXX
Mobile phone is: 0177-4769680

Manual for the Start Expert

Do this all the time

Watch Go4. Compare the pictures to reference pictures.

Important are the upper left two pictures, Profile of Start (32chn) and profile of Veto (16chn). If channels are missing (within a reasonable statistics), follow the guideline below or call me.

Do this once per shift

nothing yet

Checklist if something is strange

No signal at all from start

• Is there beam?
• Check HV in Epics
• Check Low Voltage
• Check Meantimer Tresholds
• Check TRB (DAQ should do this)

some channels (<4) are missing

• Check Meantimer Tresholds

a lot of channels (>4) are missing

• Check Meantimer Tresholds
• Check HV
• Check Low Voltage

Meantimer Tresholds cannot be read/set by Epics

• Check if there is the "usual" GSI network problem, if yes, have patience
• Check if Crate is on. This can be done by connecting to the Crate CPU. Do a ping cpuname. If CPU is not responding, Check if the Crate has Power. Use a webbrowser to http://haepc04.gsi.de.

How http://haepc04.gsi.de should look like

Channel 1 is Low Voltage, Channel 8 is the crate with the meantimers.
Switching on/off should only be done if start detector is not needed at taht time (e.g. no file is written).

How http://haepc05.gsi.de should look like

Any action here should be done by or together with DAQ operator. Switching on/off the TRB needs a DAQ restart!

-- BjoernSpruck - 02 May 2006