CP Violation in Hyperon Decays
The HyperCP (E871) collaboration at Fermilab is searching
for asymmetries between matter and antimatter, or CP violation,
in charged-Xi and Lambda hyperon decays, as well as for rare
and forbidden hyperon and kaon decays.
We are a collaboration of
Academica Sinica (Taiwan),
University of California at Berkeley,
University of Guanajuato,
Illinois Institute of
University of Lausanne,
Lawrence Berkeley Lab,
University of Michigan,
University of South Alabama,
University of Virginia.
We built a very high-rate spectrometer with which we
accumulated, in the 1997 and 1999 fixed target running periods,
one of the largest data sets every recorded by a particle physics experiment:
231 billion events, or 120 Terabytes of data, on 29,401 Exabyte tapes.
Analysis of the data is mature, highlights being:
For copies of our publications click
- A factor of 20 improvement over the best previous limit in the
search for CP violation in charged-Xi and Lambda hyperon decays.
- Evidence for the rarest baryon decay ever observed:
Sigma-plus -> proton + mu-plus + mu-minus.
- A high-statistics null search for the Theta-plus(1.54) pentaquark.
- Precision measurements of the parameters in the Xi-minus ->
Lambda + pi-minus decay.
- First observation of the flavor-changing neutral-current (FCNC) decay
K-minus -> pi-minus + mu-plus + mu-minus, as well as the charge
conjugate decay, a measurement that resolved a discrepancy between two
- Searches for strangeness-changing two decays and lepton-number
violating decays to are orders of magnitude more sensistive than
If you have any questions about the experiment, please contact either
Craig Dukes (craigdukes at virginia.edu)
or Kam-Biu Luk (k_luk at lbl.gov).
[Physics of HyperCP]
maintained by: Craig Dukes
Security, Privacy, Legal