Difference between revisions of "Minutes-1-15-2015"
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== CDC update == | == CDC update == | ||
− | - Mike presented a report linked above: he and Simon found a parameter in the time-based track reconstruction that was not set correctly. After fixing this the efficiency is much higher (in the >90s% region). The residuals vs drift time has an offset ~300microns at >100ns which | + | - Mike presented a report linked above: he and Simon found a parameter in the time-based track reconstruction that was not set correctly. After fixing this the efficiency is much higher (in the >90s% region). The residuals vs drift time has an offset ~300microns at >100ns which is interpreted as an indication for a different (faster) gas mixture. Note: the results presented are with magnetic field and the tracking was done with time-to-distance as simulated with Garfield for that field. Next step: to extract the time-to-distance from the data. Mike also presented the tool he made for reading/viewing one crate of f125s using pulser. |
- CDC efficiency to be discussed on the next meeting. | - CDC efficiency to be discussed on the next meeting. | ||
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- Vlad used Mike's tool to test the bad FDC channels (see logbook entry). Out of 8 channels, 7 could not see the pulser signal (applied at the input of the pre-amp), i.e. having issues with the pre-amp, cable, connector or the fADC. Chris and Nick will check the 3M connectors for these channels. | - Vlad used Mike's tool to test the bad FDC channels (see logbook entry). Out of 8 channels, 7 could not see the pulser signal (applied at the input of the pre-amp), i.e. having issues with the pre-amp, cable, connector or the fADC. Chris and Nick will check the 3M connectors for these channels. | ||
− | - | + | - From the alcohol consumption (~0.4l/30days for FDC and _0.6l/30days for the CDC according to Scot) Lubomir estimated ~0.8% alcohol in the FDC and ~0.4% for the CDC, very crude estimate!!! From the vapor pressure estimations we get the same order of 0.5-1% alcohol. Since the pressure in the alcohol bubbler varies between 7-12psi the alcohol percentage would vary too. As a quick fix we will make the pressure range smaller. |
− | - | + | - Lubomir simulated with Garfield the effect of adding 1% propanol to the standard gas of 40/60 Ar/CO2. From the attached plots one can see ~6% decrease in the drift velocity, i.e. opposite to the effect observed in the data. If this is true we would expect much bigger deviation from the standard 40/60 Ar/CO2 mixture than what was estimated from the drift velocity to be 46/54 (see January 8 meeting). We are looking now for a way to measure the gas percentages in the mixture. |
+ | |||
== Electronics == | == Electronics == | ||
− | - Nick and Chris started | + | - Nick and Chris started modifying the HVBs: adding capacitors, milling retainers. Some dust (like rust) was found on the top HVBs |
- Fernando ordered HV connectors that are needed to built the filter for the CAEN HV. CAEN are interested in this and they have already built such a box in a VME module frame (for one HV cable). We will get one of this for testing. CAEN are interested also in building the final filter-boxes, no discussions yet if they want to charge us for this. | - Fernando ordered HV connectors that are needed to built the filter for the CAEN HV. CAEN are interested in this and they have already built such a box in a VME module frame (for one HV cable). We will get one of this for testing. CAEN are interested also in building the final filter-boxes, no discussions yet if they want to charge us for this. |
Revision as of 17:40, 16 January 2015
January 15, 2015 FDC+CDC meeting
Connection
- Instructions for Bluejeans meeting connection
- FDC meeting ID: 290664653
- To join via a Web Browser, go to the page [1] https://bluejeans.com/290664653.
Agenda
- File:CDCUpdate15Jan2015.pdf (Mike)
- FDC update
- Electronics fADC125 replacements (Cody)
- Engineering Chiller Interlock (Dave)
- Other