相关论文: Performance of the OPAL Si-W luminometer at LEP I-…
The measurement of small-angle Bhabha scattering is used to determine the luminosity at the OPAL interaction point for the LEP I data recorded between 1993 and 1995. The measurement is based on the OPAL Silicon-Tungsten Luminometer which is…
Purpose: Luminosity measurement at the Circular Electron-Positron Collider (CEPC) is required to achieve 10^-4 precision when operating at the center-of-mass energy of the Z-pole. Approximately 10^12 Z-bosons will be collected to refine…
The integrated luminosities of the data samples collected in the BESIII experiment in 2016--2017 at center-of-mass energies between 4.19 and 4.28 GeV are measured with a precision better than 1% by analyzing large-angle Bhabha scattering…
The International Linear Collider (ILC) is a proposed electron-positron collider with a center-of-mass energy of 500~GeV, and a peak luminosity of $2 \cdot 10^{34}~\mathrm{cm}^{-2}\mathrm{s}^{-1}$. The ILC will complement the Large Hadron…
The PEP-N experiment requires a fast on-line luminosity monitor of modest accuracy plus an off-line method of determining integrated luminosity with accuracy of 0.01 for each pb$^{-1}$. We propose the PEP-2 monitor, based on observing…
The pseudoscalar meson eta_b has been searched for in two-photon interactions at LEP II. The data sample corresponds to a total integrated luminosity of 617 pb^{-1} at centre-of-mass energies ranging from 161 to 209 GeV. Upper limits at a…
In 1996, after another set of upgrades, LEP began running for the first time at center-of-mass energies above the W-pair production threshold. This new energy regime is rich in physics and offers new tests of the Standard Model, increased…
Two special calorimeters are foreseen for the instrumentation of the very forward region of an ILC or CLIC detector; a luminometer (LumiCal) designed to measure the rate of low angle Bhabha scattering events with a precision better than…
Light-pair corrections to small-angle Bhabha scattering have been computed in a realistic set-up for luminosity measurements at LEP. The effect of acollinearity and acoplanarity rejection criteria has been carefully analysed for typical…
The photon structure function F_2^gamma has been measured at <Q^2> of 706 GeV^2, using a sample of two-photon events with a scattered electron observed in the OPAL electromagnetic endcap calorimeter. The data were taken during the years…
Two special calorimeters are foreseen for the instrumentation of the very forward region of the ILC detector, a luminometer designed to measure the rate of low angle Bhabha scattering events with a precision better than 10-3 and a low polar…
The study of low-angle and large-angle Bhabha scattering at LEP gives access to the running of the electromagnetic coupling. Two recent measurements of the OPAL and L3 collaborations probe the running of alpha in the regions…
The PEP-II B Factory at SLAC has been in operation with the BABAR detector since the summer of 1999. The peak currents and luminosity steadily increased through the end of the 2000 run on October 31. By that time, 0.75 A of electrons (the…
From April to July 2018, a data sample at the peak energy of the $\Upsilon(4S)$ resonance was collected with the Belle~II detector at the SuperKEKB electron-positron collider. This is the first data sample of the Belle~II experiment. Using…
A silicon-tungsten (Si-W) sampling calorimeter, consisting of 19 alternate layers of silicon pad detectors (individual pad area of 1~cm$^2$) and tungsten absorbers (each of one radiation length), has been constructed for measurement of…
In order to measure integrated luminosity with a required precision of $10^{-4}$ at the $Z^0$ pole, proposed CEPC $e^{+}e^{-}$ collider requires a luminometer, a specially designed calorimeter placed in the very forward region to identify…
The aim of this note is to characterize briefly main components of theoretical error of the small angle Bhabha measurement at LEP and to discuss critically how solid these estimates really are, from todays perspective. We conclude that the…
A prototype Silicon-Tungsten electromagnetic calorimeter (ECAL) for an International Linear Collider (ILC) detector was installed and tested during summer and autumn 2006 at CERN. The detector had 6480 silicon pads of dimension 1x1 cm^2.…
The study of Bhabha scattering at e^+e^- colliders probes the running of the electromagnetic coupling. After early measurements by the VENUS collaboration at TRISTAN and the by L3 collaboration at LEP, two recent analyses have been…
Data sets were collected with the BESIII detector at the BEPCII collider at the center-of-mass energy of $\sqrt s =$ 3.650 GeV during May 2009 and at $\sqrt s=$ 3.773 GeV from January 2010 to May 2011. By analyzing the large angle Bhabha…