910 research outputs found
O(4) symmetric singular solutions and multiparticle cross sections in theory at tree level
We solve the classical euclidean boundary value problem for tree-level
multiparticle production in theory at arbitrary energies in the case
of symmetric field configurations. We reproduce known low-energy results
and obtain a lower bound on the tree cross sections at arbitrary energies.Comment: LaTeX, 9pp + 2 Postscript figures, tar-compressed and uuencoded using
uufiles; minor Postscript bug fixe
Instanton-Like Processes in Particle Collisions: a Numerical Study of the SU(2)-Higgs Theory below the Sphaleron Energy
We use semiclassical methods to calculate the probability of inducing a
change of topology via a high-energy collision in the SU(2)-Higgs theory. This
probability is determined by a complex solution to a classical boundary value
problem on a contour in the complex time plane. In the case of small particle
number it is the probability of instanton-like processes in particle
collisions. We obtain numerically configurations with the correct topological
features and expected properties in the complex time plane. Our work
demonstrates the feasibility of the numerical approach to the calculation of
instanton-like processes in gauge theories. We present our preliminary results
for the suppression factor of topology changing processes, which cover a wide
range of incoming particle numbers and energies below the sphaleron energy.Comment: 19 pages, 5 figures. To be published in proceedings of XI-th
International School "Particles and Cosmology", Baksan, Russia 200
The indication for K geo-antineutrino flux with Borexino phase-III data
We provide the indication of high flux of K geo-antineutrino and
geo-neutrino (K-geo-()) with Borexino Phase III data.
This result was obtained by introducing a new source of single events, namely
K-geo-() scattering on electrons, in multivariate fit
analysis of Borexino Phase III data. Simultaneously we obtained the count rates
of events from Be, and CNO solar neutrinos. These count rates are
consistent with the prediction of the Low metallicity Sun model SSM B16-AGSS09.
MC pseudo-experiments showed that the case of High metallicity Sun and absence
of K-geo-() can not imitate the result of multivariate
fit analysis of Borexino Phase III data with introducing
K-geo-() events. We also provide arguments for the high
abundance of potassium in the Earth.Comment: 17 pages, 7 figures. arXiv admin note: substantial text overlap with
arXiv:2202.08531 We have corrected and expanded the section on radiogenic
heat of the Earth. Improved the quality of drawings. The results of the study
are partially described in L. B. Bezrukov, I. S. Karpikov, A. K. Mezhokh, S.
V. Silaeva and V. V. Sinev, Bulletin of the Russian Federation. 87 (7), 972
(2023
Standard Model Higgs boson mass from inflation: two loop analysis
We extend the analysis of \cite{Bezrukov:2008ej} of the Standard Model Higgs
inflation accounting for two-loop radiative corrections to the effective
potential. As was expected, higher loop effects result in some modification of
the interval for allowed Higgs masses m_min<m_H<m_max, which somewhat exceeds
the region in which the Standard Model can be considered as a viable effective
field theory all the way up to the Planck scale. The dependence of the index
n_s of scalar perturbations on the Higgs mass is computed in two different
renormalization procedures, associated with the Einstein (I) and Jordan (II)
frames. In the procedure I the predictions of the spectral index of scalar
fluctuations and of the tensor-to-scalar ratio practically do not depend on the
Higgs mass within the admitted region and are equal to n_s=0.97 and r=0.0034
respectively. In the procedure II the index n_s acquires the visible dependence
on the Higgs mass and and goes out of the admitted interval at m_H below m_min.
We compare our findings with the results of \cite{DeSimone:2008ei}.Comment: 24 paged, 9 figures. Journal version (typos fixed, expanded
discussions
Magnetic field generation in Higgs inflation model
We study the generation of magnetic field in Higgs-inflation models where the
Standard Model Higgs boson has a large coupling to the Ricci scalar. We couple
the Higgs field to the Electromagnetic fields via a non- renormalizable
dimension six operator suppressed by the Planck scale in the Jordan frame. We
show that during Higgs inflation magnetic fields with present value
Gauss and comoving coherence length of can be generated in the
Einstein frame. The problem of large back-reaction which is generic in the
usual inflation models of magneto-genesis is avoided as the back-reaction is
suppressed by the large Higgs-curvature coupling.Comment: 10 pages, RevTeX
- …