Search for the Decay tau to seven pion (pizero)
Abstract
A search for the decay of the tau lepton to seven charged pions and one or zero pizero mesons was performed using the BaBar detector at the PEP-II asymmetric-energy e+e- collider. The analysis uses 232.2 fb-1 of data at center-of-mass energies on or near the Y(4S) resonance. We observe 24 events with an expected background of 21.6+-1.3 events. Without evidence for a signal, we calculate an upper limit of BR(tau- --> 4pi- 3pi+ (pizero) nutau) < 3.0*10-7 at 90 % confidence level. This is an improvement by nearly an order of magnitude over the previously established limit. In addition, we set upper limits for the exclusive decays tau- --> 4pi- 3pi+ nutau and tau- --> 4pi- 3pi+ pizero nutau.
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.