S.Falciano, C.Luci, L.Luminari, L.Ludovici, F.Marzano, G.Medici, G.Mirabelli
(INFN Sezione di Roma and University of Rome "La Sapienza", Italy)
B.Martin (CERN, Geneva, Switzerland)X.Cai
(World Laboratory, FBLJA Project, Geneva, Switzerland)
A. Klimentov
(Institute of Theoretical and Experimental Physics, ITEP, Moscow, Russia
and Massachusetts Institute of Technology, Cambridge, USA)
(No Paper Submitted)
Abstract
The third level trigger of the L3 experiment at LEP initially has
been based on four IBM 3081/E emulators working in parallel.
In 1993/94 trigger has been upgraded to cope with the high luminosity
and a new bunch scheme currently implemented LEP. The trigger evolution
is described in terms of hardware
implementation and software architecture. The new trigger system
is based on a farm of VAXStations 4090 connected via SCSI bus
to the central DAQ system and
via FDDI to the main online computer, VAX7000-610, and L3 off-line
facilities (a farm of SGI computers).
Advantages of current implementation, software algorithms, future upgrade for Alpha computer family are discussed. Performance is given in terms of data rates, rejection factors and trigger efficiencies.
Alexei Klimentov
ITEP, Moscow, Russia and MIT, Cambridge, USA
present address : CERN division PPE/L3, 1211 Geneva 23, Switzerland
e-mail : klimentov@vxcern.cern.ch
phone : 41 22 767 6485
fax : 41 22 782 2601
Authors :
S.Falciano, C.Luci, L.Luminari, L.Ludovici, F.Marzano, G.Medici, G.Mirabelli
(INFN Sezione di Roma and University of Rome "La Sapienza", Italy)
B.Martin (CERN, Geneva, Switzerland)X.Cai
(World Laboratory, FBLJA Project, Geneva, Switzerland)A.Klimentov
(Institute of Theoretical and Experimental Physics, ITEP, Moscow, Russia
and Massachusetts Institute of Technology, Cambridge, USA)