2,177 research outputs found
A 6D interferometric inertial isolation system
We present a novel inertial-isolation scheme based on six degree-of-freedom
(6D) interferometric sensing of a single reference mass. It is capable of
reducing inertial motion by more than two orders of magnitude at 100\,mHz
compared with what is achievable with state-of-the-art seismometers. This will
enable substantial improvements in the low-frequency sensitivity of
gravitational-wave detectors. The scheme is inherently two-stage, the reference
mass is softly suspended within the platform to be isolated, which is itself
suspended from the ground. The platform is held constant relative to the
reference mass and this closed-loop control effectively transfers the low
acceleration-noise of the reference mass to the platform. A high loop gain also
reduces non-linear couplings and dynamic range requirements in the
soft-suspension mechanics and the interferometric sensing
Rescattering corrections in elastic scattering
A detailed study of the rescattering series is performed within a model,
using a generalized procedure of eikonalization and fitted to the and
elastic scattering data. We estimate and compare the various
rescattering corrections to be added to the Born contribution in the amplitude.
We find that their number is finite, whereas it increases with the energy and
the transfer, like does their importance. In the domain where data exist, we
find also that a correct computation must include, at least, all two- and
three-Reggeon exchanges and some four- and five-Reggeon exchanges. Any
approximation aiming to reduce this (large) number of exchange would be
hazardous, especially when extrapolating. We extend our estimates in the domain
of future experiments.Comment: LaTeX2e, 15 pages, 14 eps figure
Of Dips, Structures and Eikonalization
We have investigated several models of Pomeron and Odderon contributions to
high energy elastic and scattering. The questions we address
concern their role in this field, the behavior of the scattering amplitude (or
of the total cross-section) at high energy, and how to fit all high energy
elastic data. The data are extremely well reproduced by our approach at all
momenta and for sufficiently high energies. The relative virtues of Born
amplitudes and of different kinds of eikonalizations are considered. An
important point in this respect is that secondary structures are predicted in
the differential cross-sections at increasing energies and these phenomena
appear quite directly related to the procedure of eikonalizing the various Born
amplitudes. We conclude that these secondary structures arise naturally within
the eikonalized procedure (although their precise localization turns out to be
model dependent). The fitting procedure naturally predicts the appearance of a
zero at small in the real part of the even amplitude as anticipated by
general theorems. We would like to stress, once again, how important it would
be to have at LHC both and options for many questions connected
to the general properties of high energy hadronic physics and for a check of
our predictions.Comment: 28 pages, LaTeX, 7 figure
Eikonalization and Unitarity Constraints
An extensive generalization of the ordinary and quasi-eikonal methods is
presented for the and elastic scattering amplitudes, which takes
into account in a phenomenological way all intermediate multiparticle states
involving the crossing even and crossing odd combinations of Reggeons. The
formalism in this version involves a maximum of three parameters corresponding
to the intermediate states which are possible in this configuration. The
unitarity restriction is investigated and particular cases are discussed. An
interesting result that emerges concerns the Odderon trajectory intercept: we
find that unitarity dictates that this quantity {\it must} be below or equal
unity unless a very peculiar equality exists between the coupling of the
particles to the Pomeron and the Odderon.Comment: Latex2e, 22 pages, 4 eps figures included, version accepted for
publication in Eur. Phys. J. C (some comments in Sect.2 and in Conclusion and
one reference are added
Impact analysis of TOTEM data at the LHC: black disk limit exceeded
We discuss the profile of the impact--parameter dependent elastic scattering
amplitude. Extraction of impact-parameter dependence from the dataset with
inclusion of the experimental data on elastic scattering at the LHC energies
helps to reveal the asymptotics of hadron interactions. Analysis of the data
clearly indicates that the impact-parameter elastic scattering amplitude exceed
the black disk limit at the LHC energy 7TeV and the inelastic overlap function
reaches its maximum value at Comment: 5 pages, 5 figure
Chiral color symmetry and possible -boson effects at the Tevatron and LHC
A gauge model with chiral color symmetry is considered and possible effects
of the color -boson octet predicted by this symmetry are investigated in
dependence on two free parameters, the mixing angle and mass
. The allowed region in the plane is found from the
Tevatron data on the cross section and forward-backward
asymmetry of the production. The mass limits
for the -boson are shown to be stronger than those for the axigluon. A
possible effect of the -boson on the production at the LHC is
discussed and the mass limits providing for the -boson evidence at the LHC
are estimated in dependence on .Comment: 11 pages, 2 figures, accepted for publication in Modern Physics
Letters
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