| Начало > OPAL Preprints > Bestimmung einer oberen Grenze fur die Masse des tau-Neutrinos mit dem OPAL-Detektor |
| Thesis | |
| Report number | BONN-IR-98-09 |
| Title | Bestimmung einer oberen Grenze fur die Masse des tau-Neutrinos mit dem OPAL-Detektor |
| Translation of title | Determination of an upper limit for the mass of the tau-neutrino with the OPAL detector |
| Author(s) | Scharf, F (Bonn U.) |
| Publication | Bonn : Bonn Univ., 1998 - mult.. |
| Thesis note | PhD : Bonn U. : 1998 |
| Subject category | Particle Physics - Experiment |
| Accelerator/Facility, Experiment | CERN LEP ; OPAL |
| Abstract | An upper limit for the tau -neutrino mass has been determined from the decay tau to 5 pi /sup +or-/ nu /sub tau / using data collected with the OPAL detector from 1991 to 1995 in e/sup +/e/sup -/ collisions at square root (s) $9 approximately=M/sub Z0/. A limit of 43.2 MeV at 95Ø.000554330L is obtained using a two-dimensional method in the 5 pi invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously $9 published measurement using tau /sup +/ tau /sup -/ to 3h/sup +or-/v/sub tau /+3h/sup -or+/ nu tau decays, a new combined limit of m/sub nu tau / <27.6 MeV (95 CL) is obtained. (74 refs). |