Details

Autor(en) / Beteiligte

• Abazov, V M
• Adams, D L
• Alves, G A
• Avila, C
• Babukhadia, L
• Bacon, T C
• Baden, A
• Baffioni, S
• Balm, P W
• Bartlett, J F
• Begel, M
• Belyaev, A
• Bernardi, G
• Bertram, I
• Bezzubov, V A
• Bolton, T A
• Brock, R
• Bross, A
• Canelli, F
• Casey, D
• Castilla-Valdez, H
• Coppage, D
• Da Motta, H
• Demarteau, M
• Denisov, D
• Denisov, S P
• Diehl, H T
• Elvira, V D
• Engelmann, R
• Ermolov, P
• Eroshin, O V
• Evdokimov, V N
• Fisk, H E
• Fortner, M
• Fox, H
• Gao, M
• Gerber, C E
• Ginther, G
• Gounder, K
• Goussiou, A
• Gutierrez, G
• Haggerty, H
• Hagopian, S
• Heinson, A P
• Huang, Y
• Ito, A S
• Jaffré, M
• Jöstlein, H
• Kharchilava, A
• Kostritskiy, A V
• Kozlovsky, E A
• Kubantsev, M
• Lima, J G R
• Lipton, R
• Lundstedt, C
• Manankov, V
• Marshall, T
• Martin, M I
• Melanson, H L
• Merritt, K W
• Miao, C
• Montgomery, H E
• Nagy, E
• Narain, M
• Narasimham, V S
• Neal, H A
• Nunnemann, T
• Padley, P
• Papageorgiou, K
• Parua, N
• Pétroff, P
• Protopopescu, S
• Rapidis, P A
• Reay, N W
• Rockwell, T
• Rubinov, P
• Santoro, A
• Sawyer, L
• Schamberger, R D
• Schwartzman, A
• Shpakov, D
• Simak, V
• Snow, J
• Sosebee, M
• Souza, M
• Stanton, N R
• Steinbrück, G
• Strovink, M
• Stutte, L
• Taylor, W
• Van Kooten, R
• Volkov, A A
• Vorobiev, A P
• Wayne, M
• White, A
• Whiteson, D
• Yatsunenko, Y A
• Yu, J
• Zieminski, A
• Zylberstejn, A

Titel

A precision measurement of the mass of the top quark

Ist Teil von

• Nature, 2004-06, Vol.429 (6229), p.638-642

Ort / Verlag

London: Nature Publishing

Erscheinungsjahr

2004

Link zum Volltext

Quelle

Psychology & Behavioral Sciences Collection

Beschreibungen/Notizen

• The standard model of particle physics contains parameters-such as particle masses-whose origins are still unknown and which cannot be predicted, but whose values are constrained through their interactions. In particular, the masses of the top quark (Mt) and W boson (MW) constrain the mass of the long-hypothesized, but thus far not observed, Higgs boson. A precise measurement of Mt can therefore indicate where to look for the Higgs, and indeed whether the hypothesis of a standard model Higgs is consistent with experimental data. As top quarks are produced in pairs and decay in only about 10-24 s into various final states, reconstructing their masses from their decay products is very challenging. Here we report a technique that extracts more information from each top-quark event and yields a greatly improved precision (of ± 5.3 GeV/c2) when compared to previous measurements. When our new result is combined with our published measurement in a complementary decay mode and with the only other measurements available, the new world average for Mt becomes 178.0 ± 4.3 GeV/c2. As a result, the most likely Higgs mass increases from the experimentally excluded value of 96 to 117 GeV/c2, which is beyond current experimental sensitivity. The upper limit on the Higgs mass at the 95% confidence level is raised from 219 to 251 GeV/c2.