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AbstractTOTEM will measure the total pp cross-section at LHC by using a luminosity independent method based on simultaneous evaluation of the total elastic and inelastic rates. For an extended coverage of the inelastic and diffractive events, two forward tracking telescope are employed. The elastically or diffractively scattered protons are measured by a set of special detectors, which can be moved close to the circulating protons beams. The paper describes the physics reach of the experiment and the detectors which are being considered.PACS: 25.70.Ef – 21.60.Gx – 27.30.+t

An update of the searches for charginos and neutralinos in DELPHI is presented, based mainly on recent data collected at centre-of-mass energies of 161 GeV and 172 GeV. No signal is found. For a sneutrino with mass above 300 GeV/c2 and a mass difference between the chargino and the lightest neutralino above 10 GeV/c2, the lower limit at 95% confidence level on the chargino mass ranges from 84.3 GeV/c2 to the kinematical limit (86.0 GeV/c2), depending on the mixing parameters. The limit decreases for lower chargino-neutralino mass differences. The limit in the case of a light sneutrino is 67.6 GeV/c2, provided that that there is no light sneutrino with a mass within 10 GeV/c2 below the chargino mass. Upper limits on neutralino pair production cross-sections of about a picobarn are derived. The (μ,M2) domain excluded in the MSSM-GUT scenario is determined by combining the neutralino and chargino searches. These results imply a limit on the mass of the lightest neutralino which, for a heavy sneutrino, is constrained to be above 24.9 GeV/c2 for tanß >- 1. The search has also been extended to the case where the lightest neutralino is unstable and decays into a photon and a gravitino. imply a limit on the mass of the lightest neutralino which, for a heavy sneutrino, is constrained to be above 24.9 GeV/c2 for tanß >- 1. The search has also been extended to the case where the lightest neutralino is unstable and decays into a photon and a gravitino.

Data taken by DELPHI during the 1995 and 1996 LEP runs have been used to search for the supersymmetric partners of electron, muon and tau leptons and of top and bottom quarks. The observations are in agreement with standard model predictions. Limits are set on sfermion masses. Searches for long lived scalar leptons from low scale supersymmetry breaking models exclude stau masses below 55 GeV/c2 at the 95% confidence level, irrespective of the gravitino mass.

Muon pair production in the process \\(e^+e^-\\to e^+e^-\\mu^+\\mu^-\\) is studied using the data taken at LEP1 (\\(\\sqrt{s}\\simeq m_Z\\)) with the DELPHI detector during the years 1992-1995. The corresponding integrated luminosity is 138.5 pb\\(^{-1}\\). The QED predictions have been tested over the whole \\(Q^2\\) range accessible at LEP1 (from several GeV\\(^2/c^4\\) to several hundred GeV\\(^2/c^4\\)) by comparing experimental distributions with distributions resulting from Monte Carlo simulations using various generators. Selected events are used to extract the leptonic photon structure function \\(F_2^\\gamma\\). Azimuthal correlations are used to obtain information on additional structure functions, \\(F_A^\\gamma\\) and \\(F_B^\\gamma\\), which originate from interference terms of the scattering amplitudes. The measured ratios \\(F_A^\\gamma/F_2^\\gamma\\) and \\(F_B^\\gamma/F_2^\\gamma\\) are significantly different from zero and consistent with QED predictions.

An updated analysis using about 1.5 million events recorded at s=MZ\\sqrt{s} = M_Zs​=MZ​ with the DELPHI detector in 1994 is presented. Eighteen infrared and collinear safe event shape observables are measured as a function of the polar angle of the thrust axis. The data are compared to theoretical calculations in O(αs2){\\cal O} (\\alpha_s^2)O(αs2​) including the event orientation. A combined fit of αs\\alpha_sαs​ and of the renormalization scale xμx_{\\mu}xμ​ in O(αs2\\cal O(\\alpha_s^2O(αs2​) yields an excellent description of the high statistics data. The weighted average from 18 observables including quark mass effects and correlations is αs(MZ2)=0.1174±0.0026\\alpha_s(M_Z^2) = 0.1174 \\pm 0.0026αs​(MZ2​)=0.1174±0.0026. The final result, derived from the jet cone energy fraction, the observable with the smallest theoretical and experimental uncertainty, is αs(MZ2)=0.1180±0.0006(exp.)±0.0013(hadr.)±0.0008(scale)±0.0007(mass)\\alpha_s(M_Z^2) = 0.1180 \\pm 0.0006 (exp.) \\pm 0.0013 (hadr.) \\pm 0.0008 (scale) \\pm 0.0007 (mass)αs​(MZ2​)=0.1180±0.0006(exp.)±0.0013(hadr.)±0.0008(scale)±0.0007(mass). Further studies include an αs\\alpha_sαs​ determination using theoretical predictions in the next-to-leading log approximation (NLLA), matched NLLA and O(αs2\\cal O(\\alpha_s^2O(αs2​) predictions as well as theoretically motivated optimized scale setting methods. The influence of higher order contributions was also investigated by using the method of Pad\\'{e} approximants. Average αs\\alpha_sαs​ values derived from the different approaches are in good agreement. (arXiv)

A sample of 2.2 million hadronic Z decays, selected from the data recorded by the Delphi detector at Lep during 1994–1995 was used for an improved measurement of inclusive distributions of \\(\\pi^+, K^+\\) and p and their antiparticles in gluon and quark jets. The production spectra of the individual identified particles were found to be softer in gluon jets compared to quark jets, with a higher multiplicity in gluon jets as observed for inclusive charged particles. A significant proton enhancement in gluon jets is observed indicating that baryon production proceeds directly from colour objects. The maxima, \\(\\xi^*\\), of the \\(\\xi\\)-distributions for kaons in gluon and quark jets are observed to be different.

The fragmentation functions of quarks and gluons are measured in various three-jet topologies in Z decays from the full data set collected with the Delphi detector at the Z resonance between 1992 and 1995. The results at different values of transverse momentum-like scales are compared. A parameterization of the quark and gluon fragmentation functions at a fixed reference scale is given. The quark and gluon fragmentation functions show the predicted pattern of scaling violations. The scaling violation for quark jets as a function of a transverse momentum-like scale is in a good agreement with that observed in lower energy \\({\\rm e}^+{\\rm e}^-\\) annihilation experiments. For gluon jets it appears to be significantly stronger. The scale dependences of the gluon and quark fragmentation functions agree with the prediction of the DGLAP evolution equations from which the colour factor ratio \\(C_A/C_F\\) is measured to be:

The production of single photons has been studied in the reaction e(+)e(-) --> gamma +invisible particles at centre-of-mass energies of 183 GeV and 189 GeV. A previously published analysis of events with multiphoton final states accompanied by missing ene

Oscillations of B-s(0) mesons have been studied in samples selected from about 3.5 million hadronic Z decays detected by DELPHI between 1992 and 1995. One analysis uses events in the exclusive decay channels: B-s(0) --> D(s)(-)pi (+) or D(s)(-)a(1)(+) and