Difference between revisions of "Level-1 Trigger"
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[[Level 1 Group Members]] | [[Level 1 Group Members]] | ||
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| + | === Level 1 Trigger Goal === | ||
| + | The main goal of the GlueX experiment is the search of exotic mesons | ||
| + | produced in interactions of 8.4 - 9.0 GeV linearly polarized beam | ||
| + | photons with a liquid hydrogen target. The beam photons are | ||
| + | created by the 12 GeV electrons incident on a diamond crystal via | ||
| + | bremsstrahlung process. The GlueX detector will start taking data at a luminosity | ||
| + | corresponding to about 10<sup>7</sup> photons per second in the photon-beam | ||
| + | energy range of 8.4 ''<'' E<sub>''γ''</sub> ''<'' 9.0 GeV. The Level-1 trigger has to | ||
| + | reduce the rate from electromagnetic and hadronic interactions seen | ||
| + | by the GlueX detector to a level acceptable by a data acquisition for | ||
| + | writing events directly to tape, about 20 kHz. Later, the luminosity | ||
| + | will be increased by an order of magnitude to 10<sup>8</sup> photons per second. | ||
| + | For high-luminosity runs, events accepted by the Level-1 trigger will | ||
| + | be sent to the thirt level trigger at the rate which should not exceed | ||
| + | 200 kHz. The Level-3 trigger will perform an event reconstruction | ||
| + | on a PC farm allowing to further reduce low-energy photon interactions | ||
| + | and providing an additional rate reduction of about factor of 10. | ||
| + | At the same time, the Level-1 trigger has to accept all multi-particle | ||
| + | exotic meson candidates produced in the beam energy range E ''>'' 8 GeV. | ||
Revision as of 10:36, 9 December 2011
Level 1 Trigger Goal
The main goal of the GlueX experiment is the search of exotic mesons produced in interactions of 8.4 - 9.0 GeV linearly polarized beam photons with a liquid hydrogen target. The beam photons are created by the 12 GeV electrons incident on a diamond crystal via bremsstrahlung process. The GlueX detector will start taking data at a luminosity corresponding to about 107 photons per second in the photon-beam energy range of 8.4 < Eγ < 9.0 GeV. The Level-1 trigger has to reduce the rate from electromagnetic and hadronic interactions seen by the GlueX detector to a level acceptable by a data acquisition for writing events directly to tape, about 20 kHz. Later, the luminosity will be increased by an order of magnitude to 108 photons per second. For high-luminosity runs, events accepted by the Level-1 trigger will be sent to the thirt level trigger at the rate which should not exceed 200 kHz. The Level-3 trigger will perform an event reconstruction on a PC farm allowing to further reduce low-energy photon interactions and providing an additional rate reduction of about factor of 10. At the same time, the Level-1 trigger has to accept all multi-particle exotic meson candidates produced in the beam energy range E > 8 GeV.
