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# Search results

140 records were found.

## QCD Event Generators

Comment: 84 pages, LaTeX2e, eps figures included in file using filecontents environments, gzipped, uuencoded, to appear in the proceedings of the LEP 2 Workshop

## Determination of the mass of the W boson

Comment: 65 pages, latex file + 16 figures , to appear in Vol. 1, Report of the Workshop on Physics at LEP2, G. Altarelli, T. Sjostrand and F.Zwirner

## Search for Charged Higgs Bosons in $e^+ e^-$ Collisions at $\sqrt{s}$=189-202 GeV

A search for pair-produced charged Higgs bosons was performed in the high energy data collected by the DELPHI detector at LEP II at centre-of-mass energies from 189~GeV to 202~GeV\@. The three different final states, $\tau \nu \tau \nu$, $c \bar s \bar c s$ and $c \bar s \tau \nu$ were considered. New methods were applied to reject wrong hadronic jet pairings and for the tau identification, where a discriminator based on tau polarisation and polar angles was used. No excess of data compared to the expected Standard Model processes was observed and the existence of a charged Higgs boson with mass lower than 71.5 GeV/$c^2$ is excluded at the 95\% confidence level.

## Search for a fermiophobic Higgs at LEP 2

Higgs bosons predicted by the fermiophobic scenario within Two Higgs Doublets Models were searched for in the data collected by the DELPHI detector at centre-of-mass energies between 189 GeV and 202 GeV, corresponding to a total integrated luminosity of 380 pb^{-1}. No signal was found and confidence limits were derived in the framework of possible extensions of the Standard Model Higgs sector.

## Search for $\mbox{B}^0_s-\overline{\mbox{B}^0_s}$ oscillations and a measurement of $\mbox{B}^0_d-\overline{\mbox{B}^0_d}$ oscillations using events with an inclusively reconstructed vertex

Neutral B meson oscillations in the $\mbox{B}^0_s-\overline{\mbox{B}^0 _s}$ and $\mbox{B}^0_d-\overline{\mbox{B}^0_d}$ systems were studied using a sample of about 4.0 million hadronic Z decays recorded by the DELPHI detector between 1992 and 2000. Events with a high transverse momentum lepton were removed and a sample of 770 k events with an inclusively reconstructed vertex was selected. The mass difference between the two physical states in the $\mbox{B}^0_d-\over$ system was measured to be: \begin{center} $\Delta m_d = (0.531 \pm 0.025 (stat.) \pm 0.007 (syst.)) \rm ps^{-1}$. \end{center} The following limit on the width difference of these states was also obtained: \begin{center} $|\Delta\Gamma_{\rm B_d}| / \Gamma_{\rm B_d} 0.18$ at 95\% CL. \end{center} The corresponding sensitivity of this analysis is equal to 6.6 ps$^{-1}$.