Extraction of Neutrino Flux with the Low ν\nu Method at MiniBooNE Energies

We describe the application of the `low-$\nu$' method to the extraction of the neutrino flux at MiniBooNE energies. As an example, we extract the relative energy dependence of the flux from published MiniBooNE quasielastic scattering cross sections with $\nu < 0.2$ GeV and $\nu < 0.1$ GeV (here $\nu$ is the energy transfer to the target). We find that the flux extracted from the `low-$\nu$' cross sections is consistent with the nominal flux used by MiniBooNE. We fit the MiniBooNE cross sections over the entire kinematic range to various parametrizations of the axial form factor. We find that if the overall normalization of the fit is allowed to float within the normalization errors, the extracted values of the axial vector mass are independent of the flux. Within the Fermi gas model, the $Q^2$ distribution of the MiniBooNE data is described by a standard dipole form factor with $M_A=1.41\pm0.04$ GeV. If nuclear transverse enhancement in the vector form factors is accounted for, the data are best fit with a modified dipole form factor with $M_A=1.10\pm 0.03$ GeV.Comment: 5 pages, 6 figures, (presented by A. Bodek at CIPANP 2012, St. Petersburg, FL, June 2012, and at NuFact 2012, Williamsburg, VA, July 2012

GZK photons as UHECR above 1019^{19} eV

"GZK photons" are produced by extragalactic nucleons through the resonant photoproduction of pions. We present the expected range of the GZK photon fraction of UHECR, assuming a particular UHECR spectrum and primary nucleons, and compare it with the minimal photon fraction predicted by Top-Down models.Comment: Talk given at TAUP2005, Sept. 10-14 2005, Zaragoza (Spain); 3 pages, 2 figure

Neutrino-nucleon cross sections at energies of Megaton-scale detectors

An updated set of (anti)neutrino-nucleon charged and neutral current cross sections at $3~{\rm GeV} \lesssim E_\nu \lesssim 100~{\rm GeV}$ is presented. These cross sections are of particular interest for the detector optimization and data processing and interpretation in the future Megaton-scale experiments like PINGU, ORCA, and Hyper-Kamiokande. Finite masses of charged leptons and target mass corrections in exclusive and deep inelastic $(\bar\nu)\nu N$ interactions are taken into account. A new set of QCD NNLO parton density functions, the ABMP15, is used for calculation of the DIS cross sections. The sensitivity of the cross sections to phenomenological parameters and to extrapolations of the nucleon structure functions to small $x$ and $Q^2$ is studied. An agreement within the uncertainties of our calculations with experimental data is demonstrated.Comment: 4 pages, 4 figures, accepted for the VLVnT-2015 Conference proceedings, will be published on EPJ Web of Conference

Unstable superheavy relic particles as a source of neutrinos responsible for the ultrahigh-energy cosmic rays

Decays of superheavy relic particles may produce extremely energetic neutrinos. Their annihilations on the relic neutrinos can be the origin of the cosmic rays with energies beyond the Greisen-Zatsepin-Kuzmin cutoff. The red shift acts as a cosmological filter selecting the sources at some particular value z_e, for which the present neutrino energy is close to the Z pole of the annihilation cross section. We predict no directional correlation of the ultrahigh-energy cosmic rays with the galactic halo. At the same time, there can be some directional correlations in the data, reflecting the distribution of matter at red shift z=z_e. Both of these features are manifest in the existing data. Our scenario is consistent with the neutrino mass reported by Super-Kamiokande and requires no lepton asymmetry or clustering of the background neutrinos.Comment: 3 pages, revtex; references adde

Spatially-resolved probing of a non-equilibrium superconductor

Spatially resolved relaxation of non-equilibrium quasiparticles in a superconductor at ultra-low temperatures was experimentally studied. It was found that the quasiparticle injection through a tunnel junction results in modification of the shape of I-V characteristic of a remote `detector' junction. The effect depends on temperature, injection current and proximity to the injector. The phenomena can be understood in terms of creation of quasiparticle charge and energy disequilibrium characterized by two different length scales $\Lambda_{Q^{\ast}}$ $\sim5$ $\mu$m and $\Lambda_{T^{\ast}}\sim$ $40$ $\mu$m. The findings are in good agreement with existing phenomenological models, while more elaborated microscopic theory is mandatory for detailed quantitative comparison with experiment. The results are of fundamental importance for understanding electron transport phenomena in various nanoelectronic circuits.Comment: 7 pages, 5 figure

Affleck Dine leptogenesis via multiple flat directions

We investigate the Affleck-Dine mechanism when multiple flat directions have large values simultaneously. We consider in detail the case when both $LH_u$ and $H_uH_d$ flat directions are operative with a non-renormalizable superpotential. In case Hubble induced A-terms are present for these two flat directions, their initial values are determined completely by the potential and there are no ambiguities how they are mixed. Moreover, CP is violated even when the Hubble parameter is large due to the Hubble induced A-term and cross coupling in F-term, so that the lepton asymmetry is generated just after the end of inflation. As a result, compared with the case of single flat direction, the resultant lepton-to-entropy ratio is enhanced by a factor of $H_{osc}/m_{3/2}$, where $H_{osc}$ is the Hubble parameter at the onset of oscillation and $m_{3/2}$ is the gravitino mass. However, when Hubble induced A-terms do not exist, there remains indefiniteness of initial phases and CP is violated spontaneously by the phase difference between initial phase and potential minima of the hidden-sector induced A-terms. Therefore, CP-violation is not effective until the onset of the oscillation of scalar fields around the origin and there is suppression factor from thermal effect as is the case of single flat direction. In this case, the amplitude of baryon isocurvature perturbation imposes constraints on the model parameters.Comment: 18 pages, 8 figure

Long-Lived Superheavy Particles in Dynamical Supersymmetry-Breaking Models in Supergravity

Superheavy particles of masses $\simeq 10^{13}-10^{14} GeV$ with lifetimes $\simeq 10^{10}-10^{22} years$ are very interesting, since their decays may account for the ultra-high energy (UHE) cosmic rays discovered beyond the Greisen-Zatsepin-Kuzmin cut-off energy $E \sim 5 \times 10^{10} GeV$. We show that the presence of such long-lived superheavy particles is a generic prediction of QCD-like SU(N_c) gauge theories with N_f flavors of quarks and antiquarks and the large number of colors N_c. We construct explicit models based on supersymmetric SU(N_c) gauge theories and show that if the dynamical scale $\Lambda \simeq 10^{13}-10^{14} GeV$ and N_c = 6-10 the lightest composite baryons have the desired masses and lifetimes to explain the UHE cosmic rays. Interesting is that in these models the gaugino condensation necessarily occurs and hence these models may play a role of so-called hidden sector for supersymmetry breaking in supergravity.Comment: 13 pages, Late

Lorentz invariance violation in top-down scenarios of ultrahigh energy cosmic ray creation

The violation of Lorentz invariance (LI) has been invoked in a number of ways to explain issues dealing with ultrahigh energy cosmic ray (UHECR) production and propagation. These treatments, however, have mostly been limited to examples in the proton-neutron system and photon-electron system. In this paper we show how a broader violation of Lorentz invariance would allow for a series of previously forbidden decays to occur, and how that could lead to UHECR primaries being heavy baryonic states or Higgs bosons.Comment: Replaced with heavily revised (see new Abstract) version accepted by Phys. Rev. D. 6 page