Title: Preliminary Measurements of the Quark-AntiQuark Production Cross-Section in e+e- Annihilations up to LEP2 Highest Energies
Abstract: Data collected with the DELPHI detector at sqrt(s) up
to LEP2 highest energies (i.e. exceeding 205 GeV) have been used to extract
preliminary values of the cross-sections for quark-antiquark pair-production
in e+e- annihilations.
The values found were used to test the Standard Model predictions and to
seek for physics beyond it.
Title: Four Fermions Production in Neutral Current Mediated Processes with the DELPHI at LEP
Title: Measurement of the W Mass and Width in DELPHI at LEP
A measurement of the W mass and W width has been performed by the DELPHI
collaboration. During the years 1997-1999 DELPHI collected data with an
integrated luminosity of 435 pb-1 at centre of mass energies ranging from
183 to 202 GeV. LEP is currently running at energies higher than 202 GeV.
The DELPHI results and preliminary numbers presented at ICHEP 2000,
Osaka, are discussed and an overview is given of improvements in
statistical sensitivity and determination of systematic errors to be
expected for the final analysis of the total LEP2 data sample.
Title: Search for charginos and neutralinos with the DELPHI detector at LEP200
An update of the searches for charginos and neutrlinos is presented, based on the data collected by DELPHI,
at centre-of-mass energies above 192 GeV. Lower limits on the chargino mass are derived. The (mu,M2) MSSM domain
excluded by combining the chargino searches with neutralino searches is used to set a lower limit on the mass
of the lightest neutralino for high m0 and tan(beta) ge 1. Upper limits on the neutralino production cross
section times branching fraction are derived. A limit on the chargino mass independent of the difference
of mass between the chargino and neutralino is presented for high m0 and tan(beta) ge 1.
Please note that some transparencies from the LSP search people and the Nearly degenerate chargino analysis are missing:
they will be added as soon as possible.
Title: Measurements and Interpretation of Lepton-Pair Production at LEP2 energies
A preliminary analysis of the lepton-pair production in e+e- annihilations
at LEP2 center-of-mass energies using the data collected between 130 GeV
and LEP2 highest energies (i.e. exceeding 205 GeV) with the DELPHI detector
is presented. Leptonic cross-sections and forward-backward asymmetries are
evaluated for two ranges of effective invariant mass sqrt(s'). The first
range of sqrt(s') includes radiative return events to the Z0, whereas the
second range is a subset which contains the non-radiative events with a
sqrt(s') close to sqrt(s). The values obtained are used to test the
Standard Model predictions and to derive limits on possible new physics
phenomena beyond it.
Title: Measurement of the Cross Section Ratios and Forward-Backward Asymmetries of Flavour Tagged Events with DELPHI Detector at LEP2
Abstract: Preliminary results of the cross-section ratio
R_f=sigma_ffbar/sigma_had and the forward-backward asymmetry
will be presented for heavy flavours produced in the reaction
e+e-->Z/gamma*->ffbar and measured with the DELPHI detector,
at LEP collision energies ranging from 183 GeV up to 202 GeV and
Lifetime and secondary vertex information provided by DELPHI's
3-layer microvertex detector are the main ingredients of a
variable which is used to separate the quark flavours.
High purity selections are made from which R_f and A^f_fb are
The compatibility of the results with the Standard Model
expectations is evaluated.