Search results for " Anni"

Comment on the Positron Surface-State Lifetime

1984

Quand on calcule de facon coherente de l'energie de correlation des positons et la vitesse d'annihilation, la theorie explique au moins de facon qualitative la duree de vie de l'etat de surface des positons

Near-surface defect profiling with slow positrons: Argon-sputtered Al(110).

1985

We report on slow-positron measurements of atomic defect distribution near a solid surface. Defects are produced by argon-ion bombardment of an Al(110) surface in ultrahigh vacuum. Defect profiles have a typical width of 15–25 Å and contain a broader tail extending to 50–100 Å. The defect density at the outermost atomic layers saturates at high argon fluences to a few atomic percent, depending on sputtering conditions. Defect production rate at >1 keV Ar+ energies is typically 1–5 vacancy-interstitial pairs per incident ion. Molecular-dynamics simulations of the collision cascade predict similar defect distributions. Peer reviewed

Search for promptly produced heavy quarkonium states in hadronic Z decays

1996

A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z^{0} decays in the 1991-1994 DELPHI data. Prompt J/\psi, \psi(2S) and \Upsilon candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex positions. New upper limits are set at the 90 \% confidence level for {Br( Z^0 \rightarrow \left( Q \bar{Q} \right) X ) / Br( Z^0 \rightarrow \mbox{hadrons})} for various strong production mechanisms of J/\psi and \Upsilon; these range down to 0.9 \times 10^{-4}. The limits are set in the presence of a small excess (\sim 1 \% statistical probability of a background fluctuation) in the su…

Determination of the LEP centre-of-mass energy from Zγ events

1999

Radiative returns to the Z resonance (Zgamma events) are used to determine the LEP2 centre-of-mass energy from the data collected with the ALEPH detector in 1997. The average centre-of-mass energy is measured to be: E_CM = 182.50 +- 0.19(stat) +- 0.08(syst) GeV in good agreement with the precise determination by the LEP energy working group of 182.652 +- 0.050 GeV. If applied to the measurement of the W mass, its precision translates into a systematic error on M_W which is smaller than the statistical error achieved from the corresponding dataset.

Measurements of Branching Fractions andCP-Violating Asymmetries inBMeson Decays to Charmless Two-Body States Containing aK0

2003

We present measurements of branching fractions and \CP-violating asymmetries in decays of $B$ mesons to two-body final states containing a \Kz. The results are based on a data sample of approximately 88 million \upsbb decays collected with the \babar detector at the \pep2 asymmetric-energy $B$ Factory at SLAC. We measure $\BR(\Bp\to\Kz\pip) = (22.3 \pm 1.7 \pm 1.1)\times 10^{-6}$, $\BR(\Bz\to\Kz\piz) = (11.4\pm 1.7\pm 0.8)\times 10^{-6}$, $\BR(\Bp\to\Kzb\Kp) < 2.5\times 10^{-6}$, and $\BR(\Bz\to\KzKzb) < 1.8\times 10^{-6}$, where the first uncertainty is statistical and the second is systematic, and the upper limits are at the 90% confidence level. In addition, the following \CP-violating a…

Improved tau polarisation measurement

1996

Using 22 pb−1 of data collected at LEP in 1992 on the peak of the Z resonance, the ALEPH collaboration has measured the polarisation of the tau leptons decaying into $$ev\bar v, \mu v\bar v$$ ,πν, ρν and a1 ν from their individual decay product distributions. The measurement of the tau polarisation as a function of the production polar angle yields the two parametersN τ andN e, where, in terms of the axial and vector couplingsg Al andg Vl,N l=2g Vl gAl/(g Vl 2 +g 2 ). This analysis follows to a large extent the methods devised for the 1990 and 1991 data but with improvements which bring a better understanding of the systematic uncertainties. Combining the 1992 measurements with our previous…

Tiina ja jälleenrakentamisen aika Anni Polvan Tiina-kirjat kontekstuaalisin silmin

2009

Recens. a: Tito Livio Frulovisi, Hunfreidos, a cura di C. Cocco, Firenze, SISMEL-Edizioni del Galluzzo, 2014, in «Bollettino di Studi Latini» 46,1 (2…

2016

Recensione alla prima edizione dell'Hunfreidos di Tito Livio Frulovisi, poemetto epico-encomiastico scritto nel 1436 in onore del duca Humphrey di Gloucester, fratello di re Enrico V d'Inghilterra. L'edizione è stata curata da Cristina Cocco, dell'Università di Cagliari, ed è apparsa nel 2014, pubblicata dalla SISMEL-Edizioni del Galluzzo di Firenze.

Electroweak measurements in electron-positron collisions at W-boson-pair energies at LEP

2013

The ALEPH, DELPHI, L3, OPAL collaborations and LEP Electroweak Working Group.-- arXiv:1302.3415

Trend

2012

Articolo inserito nel dossier Anni 80 di Doppiozero sulla nozione di trend nelle scienze umane e nel senso comune del periodo.