Difference between revisions of "Minutes-8-21-2014"
From GlueXWiki
| Line 24: | Line 24: | ||
== DAQ == | == DAQ == | ||
| − | - Beni: testing the latest fADC125 firmware released, works except something goes wrong in the FPGA when setting event number. ROCFDC3 has problems will be excluded for the next run. We want to take data with the magnet on. The top scintillator paddle was moved as high as possible to reduce the filed on the PMTs. Actually, after the meeting Beni and Elton were able to get signals from the scintillator (after increasing the HV) and started the DAQ (FDC+CDC) with the | + | - Beni: testing the latest fADC125 firmware released, works except something goes wrong in the FPGA when setting event number. ROCFDC3 has problems will be excluded for the next run. We want to take data with the magnet on. The top scintillator paddle was moved as high as possible to reduce the filed on the PMTs. Actually, after the meeting Beni and Elton were able to get signals from the scintillator (after increasing the HV) and started the DAQ (FDC+CDC) with the coincidence trigger. |
| − | - Discussions about horizontal trigger. We need to install it back. The upstream paddles can be installed when the | + | - Discussions about horizontal trigger. We need to install it back. The upstream paddles can be installed when the target is out. Instead of the downstream paddles one can use the TOF, but it requires the GTP. |
== CDC update == | == CDC update == | ||
| Line 32: | Line 32: | ||
- Mike showed curved tracks (linked) in the CDC at 600A magnetic field. Some local curvatures seen can be explained if the drift time is taken into account. | - Mike showed curved tracks (linked) in the CDC at 600A magnetic field. Some local curvatures seen can be explained if the drift time is taken into account. | ||
| − | - Fernado: additional ground on the CDC aluminum ring to which the HV is connected has been installed. Expect to reduce the noise significantly. Grounding the HVBs directly will be done as a last resort | + | - Fernado: additional ground on the CDC aluminum ring to which the HV is connected has been installed. Expect to reduce the noise significantly. Grounding the HVBs directly will be done as a last resort and it will be done in a different way through the grounding lugs. |
== FDC update == | == FDC update == | ||
| − | - Lubomir: by applying timing cuts on the hits from the two cathodes and the wires in a cell, one can reduce the threshold down to 50 fADC units (~4mV). As a result we see now most of the "missing" cathode channels, that have problems with the conductive tape. Of course the resolution will be deteriorated but one can | + | - Lubomir: by applying timing cuts on the hits from the two cathodes and the wires in a cell, one can reduce the threshold down to 50 fADC units (~4mV). As a result we see now most of the "missing" cathode channels, that have problems with the conductive tape. Of course the resolution will be deteriorated but one can still use this information for the pattern recognition. Couple of interesting events are linked above. |
== Engineering == | == Engineering == | ||
| Line 44: | Line 44: | ||
- On Monday when the chiller failed, Wesley Moore was working on the epics communication with the device. According to Hovanes he changed the set temperature to a lower value for as short time, then the chiller failed. The plan is just to read the epics variables, and not to write anything to the device. | - On Monday when the chiller failed, Wesley Moore was working on the epics communication with the device. According to Hovanes he changed the set temperature to a lower value for as short time, then the chiller failed. The plan is just to read the epics variables, and not to write anything to the device. | ||
| − | - Luke: we installed the encoder and started measurements at the last position, but in the middle the encoder stopped working. In addition motor got disconnected from the stage. After the meeting the motor was fixed but there were still problems with the encoder. Luke will continue with | + | - Luke: we installed the encoder and started measurements at the last position, but in the middle the encoder stopped working. In addition motor got disconnected from the stage. After the meeting the motor was fixed but there were still problems with the encoder. Luke will continue with measurements at two positions. The data with the encoder is enough to compare the two measurement methods. |
== Commissioning == | == Commissioning == | ||
| − | - Curtis presented a plan for the CDC | + | - Curtis presented a plan for the CDC commissioning linked above. When aligning the photon beam several inner HVBs will be supplied by Bertan modules so that one can see the currents which may help in the beam alignment. Then the plan is to have some initial data with magnet on for a short time, then for a longer time with the magnet off, and then with the magnet on again. They are concerned that the timing algorithm on the fADC125 may not be ready for the run. Eugene: while working on the photon beam the magnet will stay at 300A which is safe; this time can be used for the initial data collection. |
- As Bill proposed on the last meeting it will be good to survey the FDC without magnetic field (planned already for September) and then to monitor one of the reflector while the magnet goes up. Eugene: the best would be to rump up the magnet when the Hall is opened in September and at the same time the survey can be done. | - As Bill proposed on the last meeting it will be good to survey the FDC without magnetic field (planned already for September) and then to monitor one of the reflector while the magnet goes up. Eugene: the best would be to rump up the magnet when the Hall is opened in September and at the same time the survey can be done. | ||
| Line 54: | Line 54: | ||
== Other == | == Other == | ||
| − | - Beni: Scot put alcohol in the | + | - Beni: Scot put alcohol in the bubblers, we will monitor the chamber behavior. |
| − | + | ||
| − | + | ||
Revision as of 10:52, 22 August 2014
August 21, 2014 FDC+CDC meeting
Agenda
- DAQ (Beni)
- CDC status Curved Tracks (Mike, Beni)
- FDC status scattering event, horizontal shower event (Lubomir)
- Electronics (Chris, Nick)
- Engineering (Bill)
- Chiller
- Cathode scan (Luke)
- Commissioning Wiki Page, CDC, FDC commissioning plan (all)
- Other
Instructions for Bluejeans meeting connection
FDC meeting ID: 290664653
Minutes
Participants: Curtis, Naomi (CMU), Sean (NU), Beni, Mike, Luke, Eugene, Chris, Nick, Dave, Bill, Fernando, Sergey, Vlad and Lubomir (JLab).
