16,579 research outputs found

### Constraints on neutrino decay lifetime using long-baseline charged and neutral current data

We investigate the status of a scenario involving oscillations and decay for
charged and neutral current data from the MINOS and T2K experiments. We first
present an analysis of charged current neutrino and anti-neutrino data from
MINOS in the framework of oscillation with decay and obtain a best fit for
non-zero decay parameter $\alpha_3$. The MINOS charged and neutral current data
analysis results in the best fit for $|\Delta m_{32}^2| = 2.34\times
10^{-3}$~eV$^2$, $\sin^2 \theta_{23} = 0.60$ and zero decay parameter, which
corresponds to the limit for standard oscillations. Our combined MINOS and T2K
analysis reports a constraint at the 90\% confidence level for the neutrino
decay lifetime $\tau_3/m_3 > 2.8 \times 10^{-12}$~s/eV. This is the best limit
based only on accelerator produced neutrinos

### Exponential decay of correlation for the Stochastic Process associated to the Entropy Penalized Method

In this paper we present an upper bound for the decay of correlation for the
stationary stochastic process associated with the Entropy Penalized Method. Let
L(x, v):\Tt^n\times\Rr^n\to \Rr be a Lagrangian of the form
L(x,v) = {1/2}|v|^2 - U(x) + .
For each value of $\epsilon$ and $h$, consider the operator
\Gg[\phi](x):= -\epsilon h {ln}[\int_{\re^N} e
^{-\frac{hL(x,v)+\phi(x+hv)}{\epsilon h}}dv], as well as the reversed operator
\bar \Gg[\phi](x):= -\epsilon h {ln}[\int_{\re^N}
e^{-\frac{hL(x+hv,-v)+\phi(x+hv)}{\epsilon h}}dv], both acting on continuous
functions \phi:\Tt^n\to \Rr. Denote by $\phi_{\epsilon,h}$ the solution of
\Gg[\phi_{\epsilon,h}]=\phi_{\epsilon,h}+\lambda_{\epsilon,h}, and by $\bar
\phi_{\epsilon,h}$ the solution of \bar \Gg[\phi_{\epsilon,h}]=\bar
\phi_{\epsilon,h}+\lambda_{\epsilon,h}. In order to analyze the decay of
correlation for this process we show that the operator ${\cal L} (\phi) (x) =
\int e^{- \frac{h L (x,v)}{\epsilon}} \phi(x+h v) d v,$ has a maximal
eigenvalue isolated from the rest of the spectrum

### Constraining strangeness in dense matter with GW170817

Particles with strangeness content are predicted to populate dense matter,
modifying the equation of state of matter inside neutron stars as well as their
structure and evolution. In this work, we show how the modeling of strangeness
content in dense matter affects the properties of isolated neutrons stars and
the tidal deformation in binary systems. For describing nucleonic and hyperonic
stars we use the many-body forces model (MBF) at zero temperature, including
the $\phi$ mesons for the description of repulsive hyperon-hyperon
interactions. Hybrid stars are modeled using the MIT Bag Model with vector
interaction (vMIT) in both Gibbs and Maxwell constructions, for different
values of bag constant and vector interaction couplings. A parametrization with
a Maxwell construction, which gives rise to third family of compact stars (twin
stars), is also investigated. We calculate the tidal contribution that adds to
the post-Newtonian point-particle corrections, the associated love number for
sequences of stars of different composition (nucleonic, hyperonic, hybrid and
twin stars), and determine signatures of the phase transition on the
gravitational waves in the accumulated phase correction during the inspirals
among different scenarios for binary systems. On the light of the recent
results from GW170817 and the implications for the radius of
$\sim1.4\,\mathrm{M_{\odot}}$ stars, our results show that hybrid stars can
only exist if a phase transition takes place at low densities close to
saturation

### Experimental Observation of Coherence and Stochastic Resonances in an Electronic Chua Circuit

Stochastic and coherence resonances appear in nonlinear systems subjected to
an external source of noise and are characterized by a maximum response at the
optimal value of the noise intensity. This paper shows experimentally that it
is possible to observe them in a chaotic system. To this end we have analysed
an electronic Chua circuit running in the chaotic regime and added noise to its
dynamics. In the case of coherence resonance, we observe an optimal periodicity
for the jumps between chaotic attractors, whereas in the case of stochastic
resonance we observe a maximum in the signal-to-noise ratio at the frequency of
an external sinusoidal perturbation.Comment: 6 page

### Lorentz symmetry breaking in the noncommutative Wess-Zumino model: One loop corrections

In this paper we deal with the issue of Lorentz symmetry breaking in quantum
field theories formulated in a non-commutative space-time. We show that, unlike
in some recente analysis of quantum gravity effects, supersymmetry does not
protect the theory from the large Lorentz violating effects arising from the
loop corrections. We take advantage of the non-commutative Wess-Zumino model to
illustrate this point.Comment: 9 pages, revtex4. Corrected references. Version published in PR

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