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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.
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.
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$^{-1}$.
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