arXiv subjects

A. Campitelli

Publications and source records attributed to A. Campitelli.

3 recordsLinked to original sources

arXiv2024

Neutron Stars Mass-Radius relations analysis in the Quintessence scenario

In this paper, we explore the effects of General Relativity modification on the Mass-Radius relations of Neutron Stars induced by the presence of the Quintessence field. We consider, in particular, the Kiselev model, according to which the Quintessence field, being present in the entire Universe, might also be present around massive objects. Considering the Equation of State (EoS) for Baryonic matter BSk22 derived by A. Y. Potekhin et al., we infer the upper limit for NS masses in the presence of Quintessence. The presence of Quintessence generates a peculiar effect for which the Mass-Radius relation is unvaried and therefore the presence of Quintessence is indistinguishable from ordinary matter, at least for the Kiselev model studied in this paper.

gr-qc↗

arXiv2003

Influence of electromagnetic interferences on the gravimetric sensitivity of surface acoustic waveguides

Surface acoustic waveguides are increasing in interest for (bio)chemical detection. The surface mass modification leads to measurable changes in the propagation properties of the waveguide. Among a wide variety of waveguides, Love mode has been investigated because of its high gravimetric sensitivity. The acoustic signal launched and detected in the waveguide by electrical transducers is accompanied by an electromagnetic wave; the interaction of the two signals, easily enhanced by the open structure of the sensor, creates interference patterns in the transfer function of the sensor. The influence of these interferences on the gravimetric sensitivity is presented, whereby the structure of the entire sensor is modelled. We show that electromagnetic interferences generate an error in the experimental value of the sensitivity. This error is different for the open and the closed loop configurations of the sensor. The theoretical approach is completed by the experimentation of an actual Love mode sensor operated under liquid in open loop configuration. The experiment indicates that the interaction depends on the frequency and the mass modifications.

physics.bio-ph↗

arXiv2003

Simultaneous surface acoustic wave and surface plasmon resonance measurements: electrodeposition and biological interactions monitoring

We present results from an instrument combining surface acoustic wave (SAW) propagation and surface plasmon resonance (SPR) measurements. The objective is to use two independent methods, the former based on adsorbed mass change measurements and the latter on surface dielectric properties variations, to identify physical properties of protein layers, and more specifically their water content. We display mass sensitivity calibration curves using electrodeposition of copper leading to a sensitivity in liquid of 150$\pm15$ $cm^2/g$ for the Love mode device used here, and the application to monitoring biological processes. The extraction of protein layer thickness and protein to water content ratio is also presented for S-layer proteins under investigation. We obtain respectively 4.7$\pm$0.7 nm and 75$\pm$15%.

cond-mat.soft↗