High Intensity Running
From GlueXWiki
Overview
This page gathers information related to high intensity (5 x 107 γ/s - 50 MHz in 8.4-9.0 GeV) GlueX running.
Reference Material
- L3 min-review Slides (7/22/2016 )
- Level-3 Trigger Meetings
- Constraints from VME and Network Interfaces
- Flux: evaluation of the photon flux for Spring 2016 - 10Mhz (8.4-9.0 GeV) with the old "50 µm" diamond, PERP mode, 5mm collimator, beam 130µA
Planning
Near-term Questions
Here is a place to gather some questions that need to be answered in order to properly plan for high intensity running.
- L1 trigger
- What is the L1 trigger rate expected for the 50 MHz beam, extrapolating the Spring 2016 conditions: the FCAL+BCAL trigger? other triggers? The accidentals should be considered.
- What is the relative drop of the trigger efficiency for a twice more stringent FCAL+BCAL trigger, which would leave 50% of the events?
- Would a ST*(FCAL+BCAL), or other coincidence help to reduce the trigger rate minimizing the efficiency loss?
- DAQ
- What are the expected data rates for each crate?
- How do the rates scale with beam intensity?
- Can we reduce the data read from each crate by dropping headers or reformatting? (e.g. fADC125 Trigger Times)
- Can we reduce the data read from each crate by reducing readout windows?
- What crates (FDC?) would limit the DAQ capabilities after the data reduction (items 2-3)?
- What are the expected data rates for each crate?
- What fraction of events will be reconstructable/usable?
- Can we reduce the data read from each crate by dropping headers or reformatting? (e.g. fADC125 Trigger Times)
- Can we reduce the data read from each crate by reducing readout windows?
- Do the tagger data rates really drop below the FDC when the windows are reduced?