arXiv subjects

A. Peralta Conde

Publications and source records attributed to A. Peralta Conde.

9 recordsLinked to original sources

arXiv2026

Charge-state dynamics of barium ions in high-pressure xenon and its implications for Barium-Tagging in $0νββ$ searches

Barium tagging (BaTa) is one of the most promising techniques for achieving a nearly background-free search for neutrinoless double-beta decay ($0νββ$) in high-pressure xenon time detection chambers. However, the experimental implementation of BaTa depends critically on the chage-state dynamics of the daughter Ba$^{2+}$ ion produced in the nuclear decay event. In this work, I review the possible recombination channels and evaluate their physical viability. The obtained results indicate that although binary recombination channels are strongly suppressed, three-body recombination assisted by neutral xenon atoms constitutes a physically plausible mechanism for the conversion of Ba$^{2+}$ into Ba$^+$ on timescales -milliseconds- comparable to the characteristic detection times in the NEXT experiment. These results suggest that the barium charge state should be regarded as a dynamical quantity with direct implications for the design and experimental implementation of BaTa techniques.

physics.atom-ph↗

arXiv2017

X-ray emission from a liquid curtain jet when irradiated by femtosecond laser pulses

Laser-based sources of ionizing radiation have attracted a considerable attention in the last years for their broad potential applications. However the stability and robustness of such sources is still an issue that needs to be addressed. Aiming to solve such problems, we propose a source that uses a liquid jet -rather than a solid- as a target for the production of X-rays. Liquid jets offer always a clean surface for every laser shot which represent a clear advantage over solids. In this work, we present an experimental characterization of the X-ray emission of such targets, and study the efficiency of the process when two temporally delayed pulses are used. According to the obtained results, the X-ray yield is comparable with commonly used targets.

physics.plasm-ph↗

arXiv2016

Propagation studies for the construction of atomic macro-coherence in dense media as a tool to investigate neutrino physics

In this manuscript we review the possibility of inducing large coherence in a macroscopic dense target by using adiabatic techniques. For this purpose we investigate the degradation of the laser pulse through propagation, which was also related to the size of the prepared medium. Our results show that, although adiabatic techniques offer the best alternative in terms of stability against experimental parameters, for very dense media it is necessary to engineer laser-matter interaction in order to minimize laser field degradation. This work has been triggered by the proposal of a new technique, namely Radiative Emission of Neutrino Pairs (RENP), capable of investigating neutrino physics through quantum optics concepts which require the preparation of a macrocoherent state.

quant-ph↗

arXiv2016

Influence of coherent adiabatic excitation on femtosecond transient signals

The transient signals derived from femtosecond pump-probe experiments are analyzed in terms of the coherent evolution of the energy levels perturbed by the excitation pulse. The model system is treated as the sum of independent two-level subsystems that evolve adiabatically or are permanently excited, depending on the detuning from the central wavelength of the excitation laser. This approach will allow us to explain numerically and analytically the convergence between the coherent and incoherent (rate equations) treatments for complex multi-level systems. It will be also shown that the parameter that determines the validity of the incoherent treatment is the distribution of states outside and inside the laser bandwidth, rather than the density of states as it is commonly accepted.

physics.atom-ph↗

arXiv2016

Laser-based X-ray and electron source for X-ray fluorescence studies

In this work we present a modification to conventional X-rays fluorescence using electrons as excitation source, and compare it with the traditional X-ray excitation for the study of pigments. For this purpose we have constructed a laser-based source capable to produce X-rays as well as electrons. Because of the large penetration depth of X-rays, the collected fluorescence signal is a combination of several material layers of the artwork under study. However electrons are stopped in the first layers allowing therefore a more superficial analysis. We show that the combination of both excitation sources can provide extremely valuable information about the structure of the artwork.

physics.ins-det↗

arXiv2015

Determination of the species generated in atmospheric-pressure laser-induced plasmas by mass spectrometry techniques

We present temporal information obtained by mass spectrometry techniques about the evolution of plasmas generated by laser filamentation in air. The experimental setup used in this work allowed us to study not only the dynamics of the filament core but also of the energy reservoir that surrounds it. Furthermore, valuable insights about the chemistry of such systems like the photofragmentation and/or formation of molecules were obtained. The interpretation of the experimental results are supported by PIC (particle in cell) simulations.

physics.plasm-ph↗

arXiv2015

A novel technique to achieve atomic macro-coherence as a tool to determine the nature of neutrinos

The photon spectrum in macrocoherent atomic de-excitation via radiative emission of neutrino pairs (RENP) has been proposed as a sensitive probe of the neutrino mass spectrum, capable of competing with conventional neutrino experiments. In this paper we revisit this intriguing possibility, presenting an alternative method for inducing large coherence in a target based on adiabatic techniques. More concretely, we propose the use of a modified version of Coherent Population Return (CPR), namely double CPR, that turns out to be extremely robust with respect to the experimental parameters, and capable of inducing a coherence close to 100% in the target.

quant-ph↗

arXiv2015

Conditions for Statistical Determination of the Neutrino Mass Spectrum in Radiative Emission of Neutrino Pairs in Atoms

The photon spectrum in macrocoherent atomic de-excitation via radiative emission of neutrino pairs (RENP) has been proposed as a sensitive probe of the neutrino mass spectrum, capable of competing with conventional neutrino experiments. In this paper we revisit this intriguing technique in order to quantify the requirements for statistical determination of some of the properties of the neutrino spectrum, in particular the neutrino mass scale and the mass ordering. Our results are sobering. We find that, even under ideal conditions, the determination of neutrino parameters needs experimental live times of the order of days to years for several laser frequencies, assuming a target of volume of order 100 cm3 containing about 10^21 atoms per cubic centimeter in a totally coherent state with maximum value of the electric field in the target. Such conditions seem to be, as of today, way beyond the reach of our current technology.

hep-ph↗

arXiv2011

Doubly resonant ultrachirped pulses

Ultrachirped pulses for which the frequency chirp is of the order of the transition frequency of a two-level atom are examined. When the chirp is large enough, the resonance may be crossed twice, for positive and negative quadrature frequencies. In this scenario the analytic signal and quadrature decompositions of the field into amplitude and phase factors turn out to be quite different. The corresponding interaction pictures are strictly equivalent, but only as long as approximations are not applied. The domain of validity of the formal rotating wave approximation is dramatically enhanced using the analytic signal representation.

quant-ph↗