Answer to the remarks on superconductivity in PdH

Abstract This is the answer to the letter of Baranowski and Debowska [Baranowski and Debowska, J. Alloys Compd. 437 (2007) L4–L5]

The KLASH Proposal

We propose a search of galactic axions with mass about 0.2 µeV using a large volume resonant cavity, about 50 m3, cooled down to 4 K and immersed in a moderate axial magnetic field of about 0.6 T generated inside the superconducting magnet of the KLOE experiment [1] located at the National Laboratory of Frascati of INFN. This experiment, called KLASH (KLoe magnet for Axion SearcH) in the following, has a potential sensitivity on the axion-to-photon coupling, gaγγ, of about 6 × 10−17 GeV−1, reaching the region predicted by KSVZ [2] and DFSZ [3] models of QCD axions

Nonuniversal temperature dependencies of the low-frequency ac magnetic susceptibility in high-T c superconductors

The complex ac magnetic susceptibilities ({\ensuremath{\chi}}_{n}={\ensuremath{\chi}}_{n}^{\ensuremath{'}}+i{\ensuremath{\chi}}_{n}^{\ensuremath{''}}) of high-${T}_{c}$ superconductors in absence of dc fields have been studied by numerically solving the nonlinear diffusion equation for the magnetic flux, where the diffusivity is determined by the resistivity. In our approach the parallel resistor model between the creep and flux flow resistivities is used, so that the crossover between different flux dynamic processes (thermally activated flux flow, flux creep, flux flow) can naturally arise. For this reason we remark that, as the frequency increases, the presence of a different nonlinearity in different regions of the I\ensuremath{-}V characteristic determines nonuniversal temperature dependencies of the {\ensuremath{\chi}}_{n}, i.e., the {\ensuremath{\chi}}_{n} are found to be not universal functions of a frequency- and temperature-dependent single parameter. Moreover, the actual frequency-dependent behavior is also shown to be strictly related to the particular pinning model chosen for the simulations. Indeed, for large values of the reduced pinning potential $(U/KTg~220)$ and for increasing frequency, a transition has been observed between dynamic regimes dominated by creep and flux flow processes. On the other hand, for smaller reduced pinning potentials, a transition from the thermally activated flux flow (Taff) to the flow regime occurs. In qualitative agreement with available experimental data but in contrast with previously used simpler models, the amplitude of the peak of the imaginary part of the first harmonic is shown to be frequency dependent. Moreover the frequency dependence of its peak temperature shows large discrepancies with approximated analytical predictions. Finally, the shapes of the temperature dependencies of the higher harmonics are found to be strongly affected by the frequency

Serum IL-17 after one course of sublingual immunotherapy in allergic rhinitis to birch

Recently, it has been reported that IL-17 may be involved in allergic reaction. Sublingual immunotherapy (SLIT) is the unique curative treatment for allergic rhinitis. This study aims at investigating whether one course of birch SLIT could affect serum IL-17 levels. The findings provided show that some IL-17 producer patients had a reduction of serum IL-17 levels after one SLIT course. Therefore, this preliminary study shows that a single pre-seasonal SLIT course may induce a significant decreasing trend in serum IL-17 levels; further study should be carried out to define the role exerted by IL-17 in allergic rhinitis

Axion search with a quantum-limited ferromagnetic haloscope

A ferromagnetic axion haloscope searches for Dark Matter in the form of axions by exploiting their interaction with electronic spins. It is composed of an axion-to-electromagnetic field transducer coupled to a sensitive rf detector. The former is a photon-magnon hybrid system, and the latter is based on a quantum-limited Josephson parametric amplifier. The hybrid system consists of ten 2.1 mm diameter YIG spheres coupled to a single microwave cavity mode by means of a static magnetic field. Our setup is the most sensitive rf spin-magnetometer ever realized. The minimum detectable field is $5.5\times10^{-19}\,$T with 9 h integration time, corresponding to a limit on the axion-electron coupling constant $g_{aee}\le1.7\times10^{-11}$ at 95% CL. The scientific run of our haloscope resulted in the best limit on DM-axions to electron coupling constant in a frequency span of about 120 MHz, corresponding to the axion mass range $42.4$-$43.1\,\mu$eV. This is also the first apparatus to perform an axion mass scanning by changing the static magnetic field.Comment: 4 pages, 4 figure

Flux dynamics in NdO1-xFxFeAs bulk sample

We present data of multi harmonic magneto-dynamic experiments. In particular, we performed ac magnetic susceptibility experiments on layered pnictide-oxide quaternary compound NdOFeAs doped with fluorine. The experiments allow measure the critical temperature and probe the flux dynamic behavior using the third harmonic component of the ac susceptibility of a NdF0.16FeAsO0.84 bulk sample as a function of temperature and frequency of the applied ac magnetic fields. Measured signals are connected with the non-linear superconducting flux dynamic behavior and are characterized by a flux critical states sustaining a superconducting critical current. In this framework the irreversibility line that describes the stable superconducting state has been extracted from the onset of the third harmonic signal vs. frequency. Finally we present also the analysis of the flux dynamic dimensionality in the investigated sample.Comment: 10 pages, 5 figure

Prevention and Preparedness of the Messina-Reggio Calabria Strait: An Earthquake Forecasting and Didactic Project

This contribution is addressed to an introductive university course on the correlation existing between radon emission and earthquakes processes held following a flipped-class approach where students receive didactic materials prior to face-to-face lessons. This research was initially started to investigate the real correlation between Radon emission from the Earth and the occurrence of strong earthquakes by using measurements of hourly Radon flow variation. During quiet seismogenic conditions, we observe an unvarying level of Radon emission in the air. Before a strong earthquake, substantial variations of Radon (222Rn) concentration have been observed in the air, probably because of the increase of thermodynamic energy inside the Earth. The physical processes affecting earthquakes are still not fully understood; therefore, we are interested in investigating a wide variety of signals observed before an earthquake, ranging from chemical, electric, and magnetic variations. The goal is to be able to estimate the earthquake magnitude, timing also location in advance with a good approximation. The experimental observation and research studies were carried out by G. Giuliani Permanent Foundation since 2002 in Abruzzo. The innovative methodology of observations with Gamma detectors allowed us to reveal a close correlation between the different physical phenomena during the preparation phase of strong earthquakes. We master the methodology of measuring the hourly flow of 222Rn gas decay, which provides a good correlation with the occurrence of strong earthquakes. To advance the reliability of our assessment, we added more parameters to our observations, such as magnetic and RF. The joint analysis advances our understanding of the processes underlying the earthquake occurrence. The experimental observation of Radon has been tested for more than a decade in the Abruzzo region. The initial results provided the baseline of reliable correlation between radon variations and earthquakes that could be used as an alert mechanism for the forthcoming seismic events. The multiparametric approach of detecting pre-earthquakes signals provided the robustness in detecting the earthquake preparation phase. There are no doubts that by expanding the network of gamma sensors, we achieve much better signal detection, which is critical for the better spatial correlation of Radon variations with the earthquake processes

Searching for galactic axions through magnetized media: QUAX status report

The current status of the QUAX R\&D program is presented. QUAX is a feasibility study for a detection of axion as dark matter based on the coupling to the electrons. The relevant signal is a magnetization change of a magnetic material placed inside a resonant microwave cavity and polarized with a static magnetic field.Comment: Contributed to the 13th Patras Workshop on Axions, WIMPs and WISPs, Thessaloniki, May 15 to 19, 201

The cryogenic magneto-optical device for terahertz radiation detection

We present here a small-scale liquid Helium (LHe) immersion cryostat with an innovative optical setup suitable to work in long wavelength radiation ranges and under applied magnetic field. The cryostat is a multi stage device with several shielding in addition to several optical stages. The system has been designed with an external liquid Nitrogen boiler to reduce the liquid bubbling. The optical and mechanical properties of the optical elements were calculated and optimized for the designed configuration while the optical layout has been simulated and optimized among different configurations based on the geometry of the device. The final design has been optimized for low noise radiation measurements of proximity junction arrays under applied magnetic field in the wavelength range λ=250-2500 µm