3,751 research outputs found
Charges in nonlinear higher-spin theory
Nonlinear higher-spin equations in four dimensions admit a closed two-form
that defines a gauge-invariant global charge as an integral over a
two-dimensional cycle. In this paper we argue that this charge gives rise to
partitions depending on various lower- and higher-spin chemical potentials
identified with modules of topological fields in the theory. The vacuum
contribution to the partition is calculated to the first nontrivial order for a
solution to higher-spin equations that generalizes AdS4 Kerr black hole of
General Relativity. The resulting partition is non-zero being in parametric
agreement with the ADM-like behavior of a rotating source. The linear response
of chemical potentials to the partition function is also extracted. The
explicit unfolded form of 4d GR black holes is given. An explicit formula
relating asymptotic higher-spin charges expressed in terms of the generalized
higher-spin Weyl tensor with those expressed in terms of Fronsdal fields is
obtained.Comment: 23 pages; V3: typos corrected; references and acknowledgement added;
example of the topological contribution to spin-4 charge added; new Section
3.1 added establishing relation of our construction for asymptotic charges
with the canonical one. Version published in JHE
Lorentz covariant form of extended higher-spin equations
The extension of nonlinear higher-spin equations in d=4 proposed in
[arXiv:1504.07289] for the construction of invariant functional is shown to
respect local Lorentz symmetry. The equations are rewritten in a manifestly
Lorentz covariant form resulting from some Stueckelberg-like field
transformation. We also show that the two field-independent central terms
entering higher-spin equations which are not entirely fixed by the consistency
alone get fixed unambiguously by the requirement of Lorentz symmetry. One of
the important advantages of the proposed approach demonstrated in the paper is
the remarkable simplification of the perturbative analysis.Comment: V2: 20 pages, typos corrected, references added. Version published in
JHE
Correcting for Distortions due to Ionization in the STAR TPC
Physics goals of the STAR Experiment at RHIC in recent (and future) years
drive the need to operate the STAR TPC at ever higher luminosities, leading to
increased ionization levels in the TPC gas. The resulting ionic space charge
introduces field distortions in the detector which impact tracking performance.
Further complications arise from ionic charge leakage into the main TPC volume
from the high gain anode region. STAR has implemented corrections for these
distortions based on measures of luminosity, which we present here.
Additionally, we highlight a novel approach to applying the corrections on an
event-by-event basis applicable in conditions of rapidly varying ionization
sources.Comment: 6 pages, 7 figures, proceedings of the Workshop on Tracking in High
Multiplicity Environments (TIME 05) in Zurich, Switzerland, submitted to
Nucl. Instr. and Meth.
Beam halo dynamics and control with hollow electron beams
Experimental measurements of beam halo diffusion dynamics with collimator
scans are reviewed. The concept of halo control with a hollow electron beam
collimator, its demonstration at the Tevatron, and its possible applications at
the LHC are discussed.Comment: 5 pages, 4 figures, in Proceedings of the 52nd ICFA Advanced Beam
Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams
(HB2012), Beijing, China, 17-21 September 201
Experimental and Theoretical Investigation into the Effect of the Electron Velocity Distribution on Chaotic Oscillations in an Electron Beam under Virtual Cathode Formation Conditions
The effect of the electron transverse and longitudinal velocity spread at the
entrance to the interaction space on wide-band chaotic oscillations in intense
multiple-velocity beams is studied theoretically and numerically under the
conditions of formation of a virtual cathode. It is found that an increase in
the electron velocity spread causes chaotization of virtual cathode
oscillations. An insight into physical processes taking place in a virtual
cathode multiple velocity beam is gained by numerical simulation. The
chaotization of the oscillations is shown to be associated with additional
electron structures, which were separated out by constructing charged particle
distribution functions.Comment: 9 pages, 8 figure
BTZ Black Hole as Solution of 3d Higher Spin Gauge Theory
BTZ black hole is interpreted as exact solution of 3d higher spin gauge
theory. Solutions for free massless fields in BTZ black hole background are
constructed with the help of the star-product algebra formalism underlying the
formulation of 3d higher spin theory. It is shown that a part of higher spin
symmetries remains unbroken for special values of the BTZ parameters.Comment: 31 pages, LaTeX; references correcte
Adherence to subcutaneous interferon beta-1a treatment using an electronic injection device:a prospective open-label Scandinavian noninterventional study (the ScanSmart study)
Background: Disease modifying drugs help control the course of relapsing remitting multiple sclerosis (RRMS); however, good adherence is needed for long-term outcomes.
Objective: To evaluate patient adherence to treatment with subcutaneous interferon beta-1a using RebiSmart® and assess injection-site reactions and treatment satisfaction.
Methods: This prospective, single-arm, open-label, noninterventional multicenter Phase IV trial included disease modifying drug-experienced mobile patients with RRMS. Adherence was measured over 12 weeks. Items 13–23, 35, 37, and 38 of the Multiple Sclerosis Treatment Concerns Questionnaire (injection-site reactions and treatment satisfaction) were recorded at 12 weeks.
Results: Sixty patients were recruited (mean age 43.7 [±SD 7.9] years; 83% female; mean years since multiple sclerosis diagnosis 6.7 [SD 4.5]). Adherence data were obtained in 54 patients only due to technical problems with six devices. Over 12 weeks, 89% (n=48) of patients had ≥90% adherence to treatment. Most patients experienced mild influenza-like symptoms and injection-site reactions, and global side effects were minimal. Most patients (78%) rated the convenience as the most important aspect of the device, and most experienced no or mild pain.
Conclusion: RRMS patients treated with subcutaneous interferon beta-1a, administered with RebiSmart, demonstrated generally good adherence, and the treatment was generally well tolerated
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