The HERA-B Experiment

/images/HERA-B Detector  
  HERA-B is a large-aperture high-rate spectrometer built for studies of collisions of 920 GeV protons with the nuclei of target wires positioned in the halo of the HERA proton beam. HERA-B was optimized to measure CP-violation in decays of B mesons into the so-called ``golden decay mode'': . This ambitious goal required picking each golden-decay event out from a background of 1011 hadronic interactions at a rate of 40 million interactions per second. This in turn required advances in radiation-hard technologies, the development of a sophisticated first level trigger and the construction of the first large integrated multi-level switch-based data acquisition and high-level trigger system.

  The experiment is located at the proton-electron accelerator HERA at DESY in Hamburg, Germany. The collaboration consists of 32 institutes and about 250 collaborators from 13 countries.

  The spectrometer was largely completed in January 2000. Commissioning work carried on to the end of the HERA running period in August, 2000. The detector and trigger commissioning will be completed at the beginning of the 2001/2 run. The remainder of the run will be devoted to measurements of the atomic number dependence of charmonium production and a measurement of the B production cross section at 920 GeV. HERA-B will extend existing measurements of  and suppression into the negative xF hemisphere and will make a first measurement of suppression in nuclear matter. The physics program of HERA-B beyond 2002 depends on the level of sensitivity acheived in the upcoming run. Possible topics include further measurements of heavy flavor production in nuclear matter, studies of B-hadrons (examples: B-baryons searches, BS mixing, rare decays), charmonium spectroscopy e.g. search for, hc(1P1), |ccg>, studies of charm mesons (e.g. D mixing).

More Information about: 

[Subdetector Descriptions]

[Achievements,Deficit and Prospects] (new talk by B. Schmidt)

[Research at DESY]

[more soon]

Questions and remarks to: webmaster
Last modified: 04. Mar 2009