Title :
First Results from the Third Level of the H1 Fast Track Trigger
Author :
Jung, A.W. ; Baird, A. ; Baldinger, R. ; Baumgartner, S. ; Beneckenstein, D. ; Berger, N. ; Boenig, M.-O. ; Caminada, L. ; Dodt, D. ; Elsen, E. ; Kolander, M. ; Kolya, S. ; Kriiger, K. ; Lohwasser, K. ; Meer, D. ; Mercer, D. ; Michels, V. ; Müller, D. ; M
Author_Institution :
Univ. of Heidelberg, Heidelberg
fDate :
April 29 2007-May 4 2007
Abstract :
To make the best possible use of the higher luminosity provided by the upgraded HERA collider, the H1 collaboration has built the Fast Track Trigger (FTT). It is integrated in the first three levels (L1-L3) of the H1 trigger scheme and provides enhanced selectivity for events with charged particles. The FTT allows the reconstruction of tracks in the central drift chambers down to 100 MeV. Within the 2.3 mus latency of the first trigger level coarse two dimensional track information in the plane transverse to the beam is provided. At the second trigger level (20 mus latency), high resolution, three dimensional tracks are reconstructed. Trigger decisions are derived from track momenta, multiplicities and topologies. At the third trigger level a farm of commercial PowerPC boards allows a partial event reconstruction. Within the L3 latency of 100 mus exclusive final states (e.g. D*,J/psi) are identified using track based invariant mass calculations. In addition an on-line particle identification of electrons and muons with additional information from other subdetectors is performed. First results obtained from the third level, which is fully operational since 2006, are presented.
Keywords :
D mesons; drift chambers; electrons; high energy physics instrumentation computing; microprocessor chips; muons; nuclear electronics; particle calorimetry; particle tracks; psi mesons; trigger circuits; 3D tracks; D* mesons; FTT; H1 Fast Track Trigger; HERA collider; J/psi mesons; PowerPC boards; calorimeter; central drift chambers; electrons; invariant mass calculations; muons; partial event reconstruction; particle identification algorithms; Collaboration; Delay; Electron accelerators; Frequency; Mesons; Physics; Positrons; Proton accelerators; Topology; Wire; Fast Track Trigger; H1; HERA; PPC; Track Trigger; invariant mass; on-line reconstruction; real time;
Conference_Titel :
Real-Time Conference, 2007 15th IEEE-NPSS
Conference_Location :
Batavia, IL
Print_ISBN :
978-1-4244-0866-5
Electronic_ISBN :
978-1-4244-0867-2
DOI :
10.1109/RTC.2007.4382858