2006/11/30 by Junhai Kang, Markus A. Luty, Salah Nasri
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1088/1126-6708/2008/09/086
published as JHEP0809:086,2008 · 13 pages, 4 figures. Minor revisions
arxiv created 2008/07/30 · openalex publication_date 2008/09/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Long-lived colored particles with masses m > 200 GeV are allowed by current accelerator searches, and are predicted by a number of scenarios for physics beyond the standard model. We argue that such "heavy partons'' effectively have a geometrical cross section (of order 10 mb) for annihilation at temperatures below the QCD deconfinement transition. The annihilation process involves the formation of an intermediate bound state of two heavy partons with large orbital angular momentum. The bound state subsequently decays by losing energy and angular momentum to photon or pion emission, followed by annihilation of the heavy partons. This decay occurs before nucleosynthesis for m < 1011 GeV for electrically charged partons and m < TeV for electrically neutral partons. This implies that heavy parton lifetimes as long as 1014 sec are allowed even for heavy partons with m ~ TeV decaying to photons or hadrons with significant branching fraction.