Search results for "Accelerator"
showing 10 items of 1507 documents
Coulomb Excitation of (142) Xe
2017
5 pags., 2 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0. -- Presented at the XXXV Mazurian Lakes Conference on Physics, Piaski, Poland, September 3–9, 2017.
An upgraded ATLAS Central Trigger for post-2014 LHC luminosities
2013
In early 2012, the Large Hadron Collider (LHC) reached instantaneous luminosities of 6.7·1033 cm−2s−1 and produced events with up to 40 interactions per colliding proton bunch. This places stringent operational and physical requirements on the ATLAS trigger in order to reduce the collision rate of up to 40 MHz when operating with design parameters to a manageable event storage rate of about 400 Hz without discarding those events considered interesting. The Level-1 trigger is the first rate-reducing step in the ATLAS trigger and primarily composed of the Calorimeter Trigger, Muon Trigger, and the Central Trigger Processor which are implemented in custom built VME electronics. The Central Tri…
Measurement of theZZProduction Cross Section and Limits on Anomalous Neutral Triple Gauge Couplings in Proton-Proton Collisions ats=7 TeVwith the AT…
2012
A measurement of the ZZ production cross section in proton-proton collisions at root s = 7 TeV using data corresponding to an integrated luminosity of 1.02 fb(-1) recorded by the ATLAS experiment a ...
Dielectric Collimators for Beam Delivery Systems*
2012
Abstract Wakefield generation by the collimation system is known to be a critical linear collider design issue. Optimization of the collimators represents a tradeoff between beam quality (halo reduction) and luminosity reduction. The primary objective is to reduce both short range (resonant) and long range (resistive) deflecting wakefields from collimators that reduce the luminosity of the machine. We consider the CLIC BDS (beam delivery system) and examine the potential for using dielectric rather than highly conducting materials for collimation. We present some examples of the flexibility gained by having control over the permittivity and conductivity of the collimator. We discuss simulation …
Precision Measurement ofLi11Moments: Influence of Halo Neutrons on theLi9Core
2008
The electric quadrupole moment and the magnetic moment of the 11Li halo nucleus have been measured with more than an order of magnitude higher precision than before, |Q| = 33.3(5) mb and mu = +3.6712(3)muN, revealing a 8.8(1.5)% increase of the quadrupole moment relative to that of 9Li. This result is compared to various models that aim at describing the halo properties. In the shell model an increased quadrupole moment points to a significant occupation of the 1d orbits, whereas in a simple halo picture this can be explained by relating the quadrupole moments of the proton distribution to the charge radii. Advanced models so far fail to reproduce simultaneously the trends observed in the r…
Dijet azimuthal correlations and conditional yields in pp and p+Pb collisions at sNN=5.02TeV with the ATLAS detector
2019
This paper presents a measurement of forward-forward and forward-central dijet azimuthal angular correlations and conditional yields in proton-proton (pp) and proton-lead (p + Pb) collisions as a p ...
In-source laser spectroscopy of75,77,78Cu: Direct evidence for a change in the quasiparticle energy sequence in75,77Cu and an absence of longer-lived…
2011
This paper describes measurements on the isotopes (75,77,78)Cu by the technique of in-source laser spectroscopy, at the ISOLDE facility, CERN. The role of this technique is briefly discussed in the ...
Status of REX-ISOLDE
2003
REX-ISOLDE [1] is a post-accelerator situated at the ISOLDE radioactive ion beam facility placed at CERN, Geneva. It’s main aim is to increase the energy of light (A < 50) radioactive ions from 60 keV to 0.8–2.2MeV/u. REX—ISOLDE uses a new concept of post-acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In a first step the radioactive ions are captured in a large gas-filled Penning trap. The task is to accumulate, cool and bunch the beam and prepare it for the injection into an electron beam ion source (EBIS). Cooling…
Positioning in a flat two-dimensional space-time
2008
The basic theory on relativistic positioning systems in a two-dimensional space-time and the analysis of the possibility of making relativistic gravimetry with these systems have been presented elsewhere [Phys. Rev. D 73 , 084017 (2006); Phys. Rev. D 74 , 104003 (2006)]. Here we summarize these results and we outline new issues on the relativistic positioning systems in Minkowski plane. We point out that the accelerations of the emitters and of the user along their trajectories are determined by the sole knowledge of the emitter positioning data and of the acceleration of only one of the emitters and only during a light echo interval.
Physical interpretation of laser phase dynamics
1990
The basic features characterizing the dynamical evolution of the phase of a detuned-laser field under an unstable regime are physically interpreted in terms of dispersive and dynamical effects. A general method for obtaining any attractor projection containing the phase information is established, which provides evidence for the heteroclinic character of the attractor in the presence of cavity detuning for any emission regime.