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arXiv · hep-ph/0301268

Z-lineshape versus 4th generation masses

S. S. Bulanov·V. A. Novikov·L. B. Okun·A. N. Rozanov·M. I. Vysotsky
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Abstract

The dependence of the Z-resonance shape on the location of the threshold of the N\bar{N} production (N is the 4th generation neutrino) is analyzed. The bounds on the existence of 4th generation are derived from the comparison of the theoretical expression for the Z-lineshape with the experimental data. The 4th generation is excluded at 95% C. L. for m_N<46.7\pm 0.2 GeV.

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S. S. Bulanov, V. A. Novikov, L. B. Okun, A. N. Rozanov, M. I. Vysotsky. 2003-02-12. Z-lineshape versus 4th generation masses. https://doi.org/10.1134/1.1634324

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