Leif Jönsson
Professor emeritus
Search for light gravitinos in events with photons and missing transverse momentum at HERA
Author
Summary, in English
A search for gravitinos produced in e(+/-)p collisions is performed using the H1 detector at HERA. The data were taken at a centre-of-mass energy of 319 GeV and correspond to an integrated luminosity of 64.3 pb(-1) for e(+)p collisions and 13.5 pb(-1) for e(-)p collisions. If R-parity is not conserved, the t-channel exchange of a selectron can produce a neutralino, which, in models where the gravitino is the lightest supersymmetric particle, subsequently decays into a photon and a light gravitino. The resulting event signature, which involves an isolated photon, a jet and missing transverse energy, is analysed for the first time at HERA. No deviation from the Standard Model is found. Exclusion limits on the cross section and on R-parity-violating Yukawa couplings are derived in a Gauge Mediated Supersymmetry Breaking scenario. The results are independent of the squark sector. Neutralinos and supersymmetric partners of the left-handed electron with masses up to 112 GeV and 164 GeV, respectively, can be ruled out at the 95% confidence level for R-parity-violating couplings lambda' equal to 1, in some parts of the parameter space of the considered model.
Department/s
- Particle and nuclear physics
Publishing year
2005
Language
English
Pages
31-42
Publication/Series
Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume
616
Issue
1-2
Document type
Journal article
Publisher
Elsevier
Topic
- Subatomic Physics
Status
Published
ISBN/ISSN/Other
- ISSN: 0370-2693