Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Impact of Acetate-Based Hydrogel Electrolyte on Electrical Performance and Stability of Eco-Friendly Supercapacitors

The electrochemical characteristics and stability of hydrogel-based environmentally friendly supercapacitors employing sodium acetate as salt have been investigated. To ensure the overall sustainability of the devices, chitosan (a biomaterial from renewable resources) and activated carbon (derived from coconut shells) have been used as a binder and filler within the electrodes, respectively. Cyclic voltammetry, galvanostatic charge/discharge, and impedance spectroscopy measurements have been performed to compare the electrochemical properties of the fabricated devices. Compared to reference electrolytes containing NaCl, the utilization of sodium acetate exhibited enhancements in energy performance and stability up to 50000 cycles. The most efficient device has been delivered approximately 10.6?Wh/kg of energy at a high-power density of about 3940?W/kg. A comprehensive investigation of the electrochemical performances has been carried out, considering both faradaic and non-faradaic processes as charge storage mechanisms within the devices. A model has been proposed to describe the storage mechanisms and to provide insights into the ageing phenomena observed during the cycling procedure

AUBADE D'OISEAUX , Valse / M. PEGURI - L. MICHAUD. LE RETOUR DES HIRONDELLES , Valse / TROGNEE-O. PAGANO. LA VALSE DES AS , Valse / G. JACQUES. BRISE NAPOLITAINE , Valse / GUERINO et PEYRONNIN ; NIVEL, siffleur

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REINE DES MUSETTES / S. PEYRONIN. LE RETOUR DES HIRONDELLES / B. PAGANO - R. TROGNES. BRISE NAPOLITAINE / QUERINO - PEYRONIN. AUBADE D'OISEAUX / M. PEGURI ; Jack DAUVIL et son Orchestre

Titre uniforme : [Retour des hirondelles]Titre uniforme : [Reine de musette]Titre uniforme : [Brise napolitaine]Titre uniforme : [Aubade d'oiseaux]Titre uniforme : [Le retour des hirondelles]BnF-Partenariats, Collection sonore - BelieveContient une table des matière

Superconducting high kinetic inductance films for quantum circuits

High-kinetic inductance disordered superconductors are gaining growing interest in the scientific community, especially for applications in the field of cQED and quantum sensing. Thin films offer the possibility to tune the inductance by optimising the chemical composition and the crystalline properties of the film, which depend on the deposition process. Tunable kinetic inductance values enable the exploration of a wide range of couplings between different elements in quantum circuits. Moreover, high-kinetic inductance resonators or artificial transmission lines can be exploited to achieve compact read-out devices and quantum circuits. In the framework of the DART WARS experiment, we have developed high-kinetic inductance thin NbTiN films for the microfabrication of low-noise and high dynamic range Kinetic Inductance Traveling Wave Parametric Amplifiers (KI-TWPAs). We present the optimisation of the deposition process via rf sputtering with a Nb80%Ti20% target, in order to reach high control on the film characteristics. The parameter landscape related to the different sputtering conditions, such as pressure, power and nitrogen flow has been explored and the thickness of the film has been exploited as fine-tuning parameter to adjust the kinetic inductance and critical temperature values. Besides the microfabrication of KI-TWPA devices, the optimised NbTiN films find direct applications for the development of a wide range of quantum technologies, such as Kinetic Inductance Detectors (KIDs), high-kinetic inductance resonators and superconducting nanowires

Modeling of Josephson Traveling Wave Parametric Amplifiers

The recent developments in quantum technologies, as well as advanced detection experiments, have raised the need to detect extremely weak signals in the microwave frequency spectrum. To this aim, the Josephson travelling wave parametric amplifier, a device capable of reaching the quantum noise limit while providing a wide bandwidth, has been proposed as a suitable cryogenic front-end amplifier. This work deals with the numerical study of a Josephson travelling wave parametric amplifier, without approximations regarding the nonlinearity of the key elements. In particular, we focus on the investigation of the system of coupled nonlinear differential equations representing all the cells of the Josephson travelling wave parametric amplifier, with proper input and output signals at the boundaries. The investigation of the output signals generated by the parametric amplification process explores the phase-space and the Fourier spectral analysis of the output voltage, as a function of the parameters describing the pump and signal tones that excite the device. Beside the expected behavior, i.e., the signal amplification, we show that, depending on the system operation, unwanted effects (such as pump tone harmonics, incommensurate frequency generation, and noise rise), which are not accounted for in simple linearized approaches, can be generated in the whole nonlinear system

Characterization of Traveling-Wave Josephson Parametric Amplifiers at T = 0.3 K

The growing interest in quantum technologies, from fundamental physics experiments to quantum computing, demands for extremely performing electronics only adding the minimum amount of noise admitted by quantum mechanics to the input signal (i.e., quantum-limited electronics). Superconducting microwave amplifiers, due to their dissipationless nature, exhibit outstanding performances in terms of noise (quantum limited), and gain. However, bandwidth and saturation power still show space for substantial improvement. Within the DARTWARS 1 1 DARTWARS (Detector Array Readout with Traveling Wave AmplifieRS), funded by Italian National Nuclear Institute (INFN), is a quantum technologies project targeted at the development of wideband superconducting amplifiers with noise at the quantum limit and the implementation of a quantum-limited readout in different types of superconducting detectors and qubit. We are developing state-of-the-art microwave superconducting amplifiers based on Josephson junction arrays and on distributed kinetic inductance transmission lines. Here we report the realization of a setup for the characterization of the performances of Josephson traveling-wave parametric amplifiers at a temperature of 300 mK. Although in the final experimental setup, these amplifiers will operate at a base temperature of about 20 mK, their characterization at 300 mK allows to evidence the main aspects of their performances, but the ultimate noise level. This represents a quick and relatively inexpensive way to test these superconductive devices that can be of help to improve their design and fabrication

Nonlinear Behavior of Josephson Traveling Wave Parametric Amplifiers

Recent advancements in quantum technologies and advanced detection experiments have underscored the pressing need for the detection of exceedingly weak signals within the microwave frequency spectrum. Addressing this challenge, the Josephson Traveling Wave Parametric Amplifier (JTWPA) has been proposed as a cryogenic front-end amplifier capable of approaching the quantum noise limit while providing a relevant bandwidth. This research is centered on a comprehensive numerical investigation of the JTWPA, without resorting to simplifications regarding the nonlinearity of the essential components. Specifically, this study focuses on a thorough examination of the system, characterized by coupled nonlinear differential equations representing all components of the device. Proper input and output signals at the device's boundaries are considered. The analysis of the output signals undergoing the parametric amplification process involves a detailed exploration of phase-space dynamics and Fourier spectral analysis of the output voltage. This study is conducted while considering the parameters ruling the response of the device under pump and signal excitations. In addition to the expected signal amplification, the findings reveal that the nonlinear nature of the system can give rise to unforeseen phenomena, depending on the system's operational conditions, which include: the generation of pump tone harmonics, modulation of the signal gain, and incommensurate frequency generation—effects that are not easily accommodated by simplistic linearized approaches

Nédemax mese (Leucoselect, Lymphaselect, Bromelain) in the treatment of chronic venous disease: a multicenter , obbservational study

BACKGROUND: Chronic venous disease (CVD)is major health concern; however,there remains a need to improve treatment approaches.Nédemax Mese , a nutritional supplementation consisting of Leucoselect 300 mg,Lymphaselect 100 mg and Bromelain 100 mg, is a patented formulation thah may have a role in the treatment of CVD. In this prospective , multicenter study conducted at 54 Italian centers, we investigated the effectiveness of Nédemax Mese in a large sample of CVD patients