1,119 research outputs found
Z' Coupling Information from the LHeC
If the LHC discovers a -like state the extraction of its couplings to the
particles of the Standard Model becomes mandatory in order to determine the
nature of the underlying new physics theory. It has been well-known for some
time that the direct measurements performed at the LHC in the Drell-Yan channel
cannot determine these parameters uniquely in a model-independent manner even
if large integrated luminosities, , become available and the
is relatively light \lsim 1.5 TeV. Here we examine the possibility that
a proposed collider upgrade at the LHC, the LHeC, with TeV could be helpful with such coupling determinations in the years
before a Linear Collider is constructed. We show that the polarization and
charge asymmetries constructed from the cross sections for these processes can
be useful in this regard depending upon the specific values of the particular
model parameters.Comment: 16 pages, 9 figs, minor modification
Exclusive processes in electron - ion collisions
The exclusive processes in electron-ion () interactions are an important
tool to investigate the QCD dynamics at high energies as they are in general
driven by the gluon content of the target, which is strongly subject to parton
saturation effects. In this paper we compute the cross sections for the
exclusive vector meson production as well as the deeply virtual Compton
scattering (DVCS) relying on the color dipole approach and considering the
numerical solution of the Balitsky-Kovchegov equation including running
coupling corrections (rcBK). The production cross sections obtained with the
rcBK solution and bCGC parametrization are very similar, the former being
slightly larger.Comment: 6 pages, 4 figure
A Storage Ring based Option for the LHeC
The LHeC aims at the generation of hadron-lepton collisions with center of mass energies in the TeV scale and luminosities of the order of by taking advantage of the existing LHC 7 TeV proton ring and adding a high energy electron accelerator. This paper presents technical considerations and potential parameter choices for such a machine and outlines some of the challenges arising when an electron storage ring based option, constructed within the existing infrastructure of the LHC, is chosen
Next-to-leading order QCD corrections to Higgs boson production in association with a photon via weak-boson fusion at the LHC
Higgs boson production in association with a hard central photon and two
forward tagging jets is expected to provide valuable information on Higgs boson
couplings in a range where it is difficult to disentangle weak-boson fusion
processes from large QCD backgrounds. We present next-to-leading order QCD
corrections to Higgs production in association with a photon via weak-boson
fusion at a hadron collider in the form of a flexible parton-level Monte Carlo
program. The QCD corrections to integrated cross sections are found to be small
for experimentally relevant selection cuts, while the shape of kinematic
distributions can be distorted by up to 20% in some regions of phase space.
Residual scale uncertainties at next-to-leading order are at the few-percent
level.Comment: 17 pages, 7 figures, 1 tabl
Inconsistent boundaries
Research on this paper was supported by a grant from the Marsden Fund, Royal Society of New Zealand.Mereotopology is a theory of connected parts. The existence of boundaries, as parts of everyday objects, is basic to any such theory; but in classical mereotopology, there is a problem: if boundaries exist, then either distinct entities cannot be in contact, or else space is not topologically connected (Varzi in Noûs 31:26–58, 1997). In this paper we urge that this problem can be met with a paraconsistent mereotopology, and sketch the details of one such approach. The resulting theory focuses attention on the role of empty parts, in delivering a balanced and bounded metaphysics of naive space.PostprintPeer reviewe
The Large Hadron-Electron Collider (LHEC) at the LHC
Sub-atomic physics at the energy frontier probes the structure of the fundamental quanta of the Universe. The Large Hadron Collider (LHC) at CERN opens for the first time the ‘terascale’ (TeV energy scale) to experimental scrutiny, exposing the physics of the Universe at the subattometric (∼ 10−19 m, 10−10 as) scale. The LHC will also take the science of nuclear matter to hitherto unparalleled energy densities. The hadron beams, protons or ions, in the LHC underpin this horizon, and also offer new experimental possibilities at this energy scale. A Large Hadron electron Collider, LHeC, in which an electron (positron) beam of energy 60 to 140 GeV is in collision with one of the LHC hadron beams, makes possible terascale leptonhadron physics. The LHeC is presently being evaluated in the form of two options, ‘ring-ring’ and ‘linac-ring’, either of which operate simultaneously with pp or ion-ion collisions in other LHC interaction regions. Each option takes advantage of recent advances in radio-frequency, in linear acceleration, and in other associated technologies, to achieve ep luminosity as large as 1033 cm−2s−1
Prospects for at CERN in NA62
The NA62 experiment will begin taking data in 2015. Its primary purpose is a
10% measurement of the branching ratio of the ultrarare kaon decay , using the decay in flight of kaons in an unseparated
beam with momentum 75 GeV/c.The detector and analysis technique are described
here.Comment: 8 pages for proceedings of 50 Years of CP
Linac-LHC EP Collider Options
We describe various parameter scenarios for a ring-linac ep collider based on LHC and an independent electron linac. Luminosities between and can be achieved with a s.c. linac, operated either in pulsed or in cw mode, with optional recirculation, at a total electric wallplug power of order 20 MW. Higher luminosities, of several can be reached by investing more electric power or by energy recovery. Finally, merits of a linac-ring ep collider are discussed
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