trgFrame status (Ed Frank) July 1996
Overview
trgFrame is a project aimed at providing the following functions for trigger simulation studies:
- Hit mixing between base physics events and multiple sources of background, including sampling of rate probabilities, distribution over particle bunches, and consideration of empty bunches.
- Data and control interface between the reconstruction system's C++ based Framework and the Fortran based trigger packages trgEM and trgDC.
- Direct access to simulation data (XDR format) without the need for custom ASCII files.
- Event level synchronization of EMC and DCH trigger simulations.
- Synchronization of EMC and DCH trigger simulations at the level of Fast Control clock ticks.
- Capability to simulate the Global Trigger, by virtue of the synchronization mentioned above.
- Simulation of the Fast Control system's clocks. This allows conversion between clock tick, beam crossing number, and time for clocks related to the accelerator clock by powers of two. Random synchronization of the various clocks is simulated.
- Random number generation interface and initialization.
Status
All capabilities described above are complete. The code has been used for detailed EMC trigger simulations, including studies that require consideration of backgrounds. Background rates in the DCH trigger have been obtained and compared with previous
stand-alone studies. With a few exceptions, trgFrame is essentially a completed project.
Contains about 6,000 lines of C++ and F77 code.
Last tested with SRT release 1.0.3.
Plans
Having built it, it is time to take it apart: interface codes should be migrated into the trgDC and trgEM packages. The mixer code should be migrated into the Framework package. This leaves the FC clocks, global trigger, and random number components which
can either become packages, or migrate into the reconstruction utilities package.
Manpower
Ed Frank, package coordinator, developer and user
Paul Dauncey, developer and user
Several other users
Needs from other parts of simulation
Because of the large data samples needed to perform trigger studies, and because real analysis is done, work on trgFrame has affected the designs of the Framework, dbio (C++ -> F77 copy-back and data versioning), and the AbsEvent. On the one hand this
is good, but on the other hand it distracts reconstruction design from its most immediate goals. It is important for the simulation group to realize this and therefore consider carefully any actions that lead to data versioning issues in dbio.
The trigger analysis scheme is to output hit level information from BBSIM. Digitization is done externally to allow flexibility. It is thus very important that the GHit dbio objects be (1) decoupled completely from digi objects and (2) complete so that
all reasonable digitization ideas can be accomplished without the need to re-simulate at the hit level.
These requirements go beyond trgFrame, but I mention them here because they are important to Level 3 trigger studies, which was a large reason for building trgFrame.
SRT integration
Fully functional version available in SRT release 1.0.4. Independent of BBSIM. |
