2008/11/10 by Matthew J. Strassler, Strassler, Matthew J.
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.48550/arxiv.0811.1560
21 pages, 3 figures; v2, changed wording on request (content unchanged)
openalex publication_date 2008/11/10 · arxiv created 2008/11/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A recent paper by the CDF collaboration suggests (but does not claim) an anomalous event sample containing muons produced with large impact parameter, often with high multiplicity and at small angles from one another. This curious hint of a signal is potentially consistent with the hidden valley scenario, as well as with some other classes of models. Despite its tenuous nature, this hint highlights the experimental difficulties raised by such signals, and merits some consideration. Some of the simplest interpretations of the data, such as a light neutral particle decaying to muon and/or tau pairs, are largely disfavored; three-body decays to ττν appear slightly better. An alternative speculative possibility -- a "micro-cascade decay" -- might be consistent with the data. It is suggested that the experimentalists involved provide additional plots showing invariant mass distributions of same- and opposite-sign dimuon pairs, invariant masses of various classes of displaced vertices, and spatial correlations among vertices within a cone.