1,258 research outputs found
Z' Searches: From Tevatron to LHC
The CDF collaboration has set lower limits on the masses of the Z' bosons
occurring in a range of E_6 GUT based models. We revisit their analysis and
extend it to certain other E_6 scenarios as well as to some general classes of
models satisfying the anomaly cancellation conditions, which are not included
in the CDF analysis. We also suggest a Bayesian statistical method for finding
exclusion limits on the Z' mass, which allows one to explore a wide range of
the U(1)' gauge coupling parameter. This method also takes into account the
effects of interference between the Z' and the SM gauge bosons.Comment: 5 pages. Talk given at the XXIInd Rencontres de Blois, Loire, France,
16-20 July 201
Constraints on the mass and mixing of Z' bosons
We tested several models in which the Standard Model (SM) gauge group is
extended by an additional U(1) gauge symmetry, against available electroweak
precision data to impose limits on the mass of the neutral Z' boson, M_Z',
predicted in all such models, and on the Z-Z' mixing angle, theta_ZZ', at 95%
C.L. We found lower limits on M_Z' of order 1 TeV in most cases, while
theta_ZZ' was found to be constrained to very small values.Comment: Format fixed, 5 pages, 2 figures, Talk given at the 17th
International Conference on Supersymmetry and the Unification of Fundamental
Interactions (SUSY09), Boston, MA, USA, 5-10 June 2009, to be published in
the conference proceedings (AIP
Energy from the gauge invariant observables
For a classical solution |Psi> in Witten's cubic string field theory, the
gauge invariant observable is conjectured to be equal to the
difference of the one-point functions of the closed string state corresponding
to V, between the trivial vacuum and the one described by |Psi>. For a static
solution |Psi>, if V is taken to be the graviton vertex operator with vanishing
momentum, the gauge invariant observable is expected to be proportional to the
energy of |Psi>. We prove this relation assuming that |Psi> satisfies equation
of motion and some regularity conditions. We discuss how this relation can be
applied to various solutions obtained recently.Comment: 27 pages; v5: minor revision in section 2, results unchange
Misfits in Skyrme-Hartree-Fock
We address very briefly five critical points in the context of the
Skyrme-Hartree-Fock (SHF) scheme: 1) the impossibility to consider it as an
interaction, 2) a possible inconsistency of correlation corrections as, e.g.,
the center-of-mass correction, 3) problems to describe the giant dipole
resonance (GDR) simultaneously in light and heavy nuclei, 4) deficiencies in
the extrapolation of binding energies to super-heavy elements (SHE), and 5) a
yet inappropriate trend in fission life-times when going to the heaviest SHE.
While the first two points have more a formal bias, the other three points have
practical implications and wait for solution.Comment: 9 pages, 4 figure
Recent Developments in Precision Electroweak Physics
Developments in precision electroweak physics in the two years since the
symposium are briefly summarized.Comment: Update on recent developments, prepared for the publication of the
Proceedings of Alberto Sirlin Symposium, New York University, October 2000.
10 pages, 1 figur
Crime, Punishment, and \u3cem\u3eRomero\u3c/em\u3e: An Analysis of the Case Against California\u27s Three Strikes Law
In a well-received study, Crime and Punishment in California: The Impact of Three Strikes and You\u27re Out, Franklin E. Zimring, Sam Kamin, and Gordon Hawkins assert that California\u27s Three Strikes law has failed to deter crime. The authors submit that the study has not provided sufficient statistical evidence to prove that Three Strikes does not deter crime. The authors argue that the statistical methodology employed in the study was flawed, and that this flaw created a distorted view of the deterrent effect of Three Strikes. The authors do not attempt to demonstrate that Three Strikes deters crime; however, they do produce evidence to that effect
Relevant Deformations in Open String Field Theory: a Simple Solution for Lumps
We propose a remarkably simple solution of cubic open string field theory
which describes inhomogeneous tachyon condensation. The solution is in
one-to-one correspondence with the IR fixed point of the RG-flow generated in
the two--dimensional world-sheet theory by integrating a relevant operator with
mild enough OPE on the boundary. It is shown how the closed string overlap
correctly captures the shift in the closed string one point function between
the UV and the IR limits of the flow. Examples of lumps in non-compact and
compact transverse directions are given.Comment: 45 pages. v2: typos and minor improvements. v3: submitted to jhe
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