15,329 research outputs found
Status of SM calculations of b > s transitions
We report recent progress in SM calculations of transitions. We
discuss the first NNLL prediction of the branching
ratio, including important additional subtleties due to non-perturbative
corrections and logarithmically-enhanced cut effects, and also recent results
on the inclusive mode . Moreover, new results on
the corresponding exclusive modes are reviewed. Finally, we comment on the
present status of the so-called puzzle in hadronic
transitionsComment: 10 pages, 6 figures, minor changes, published versio
The Structure of Quasi-Real and Virtual Photons
This review covers the measurements of the QED and QCD structure of
quasi-real and virtual photons from the reaction ee --> ee gamma* gamma(*) -->
ee X.Comment: Invited talk given at the PHOTON 99 Conference, Freiburg, Germany,
May 1999, to appear in the Proceeding
Combination procedure for the precise determination of Z boson parameters from results of the LEP experiments
The precise determination of the Z boson parameters from the measurements at the Z resonance by the four collaborations ALEPH, DELPHI, L3 and OPAL in e+e- collisions at the large electron positron collider LEP at CERN is a landmark for precision tests of the electroweak theory. The four experiments measured quantities which were used to extract the mass and width of the Z boson, the hadronic cross-section at the pole of the resonance, the ratio of hadronic and leptonic decay widths, and the leptonic forward-backward asymmetries at the pole. The combination procedure based on these parameters is presented in this paper
Proposal to establish a Sponsoring Consortium for Open Access Publishing in Particle Physics
In the present proposal, the publishers' subscription income from multiple institutions is replaced by an "author-side" funding. Journals are paid through contracts between publishers and a single financial partner, the "Sponsoring Consortium for Open Access Publishing in Particle Physics" (SCOAP3). SCOAP3 is envisioned as a global network of funding agencies, research laboratories, and libraries that will contribute the necessary funding; each SCOAP3 partner will recover its contribution from the cancellation of journal subscriptions. This model avoids the obvious disadvantage of authors being directly charged for the OA publication of their articles, which is perceived as an even higher barrier than subscription charges, in particular for theoretical physicists from small institutions who account for the vast majority of HEP papers. The financing and governance of SCOAP3 will follow as much as possible the example of the memoranda of understanding governing large research collaborations. Its partners will contribute on a pro-rata basis according to the number of scientific publications from their country or laboratory in a reference period
Final LHC Synchronization Test a Success
Geneva, 25 August 2008. CERN has today announced the success of the second and final test of the Large Hadron Colliderâs beam synchronization systems which will allow the LHC operations team to inject the first beam into the LHC. Friday evening 22 August, a single bunch of a few particles travelled down the transfer line from the Super Proton Synchrotron (SPS) accelerator to the LHC. After a period of optimization, one bunch was kicked up from the transfer line into the LHC beam pipe and steered counter-clockwise about 3 kilometres around the LHC. âThanks to a fantastic team, both the clock-wise and counter-clockwise tests went without a hitch. We look forward to a resounding success when we make our first attempt to send a beam all the way around the LHC,â said Lyn Evans, LHC Project Leader. Both the counter-clockwise and clockwise tests are part of the preparations to ready the LHC, the worldâs most powerful particle accelerator, for the eventual acceleration and collision of two beams at an energy of 5 TeV per beam. This unprecedented event is foreseen to take place by end 2008
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