A. Romero Vidal
A5106178307- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Particle Detector Development and Performance
- Black Holes and Theoretical Physics
- Atomic and Subatomic Physics Research
- Computational Physics and Python Applications
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Nuclear physics research studies
- Superconducting Materials and Applications
- Radioactive Decay and Measurement Techniques
- High-pressure geophysics and materials
- Stochastic processes and statistical mechanics
- Radiation Detection and Scintillator Technologies
- Ionosphere and magnetosphere dynamics
- Nuclear Physics and Applications
- Particle accelerators and beam dynamics
- Quantum Mechanics and Applications
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Atomic and Molecular Physics
- Muon and positron interactions and applications
Universidade de Santiago de Compostela
2016-2025
Universitat de València
2023
Instituto de Física Corpuscular
2023
Institute of High Energy Physics
2020
Central China Normal University
2020
University of Chinese Academy of Sciences
2020
Peking University
2020
State Key Laboratory of Nuclear Physics and Technology
2020
Tsinghua University
2020
Centro Brasileiro de Pesquisas Físicas
1965-2019
The $\bar{K}N$ system at threshold is a sensitive testing ground for low energy QCD, especially the explicit chiral symmetry breaking. Therefore, we have measured $K$-series x rays of kaonic hydrogen atoms DA$\Phi$NE electron-positron collider Laboratori Nazionali di Frascati, and determined most precise values strong-interaction energy-level shift width $1s$ atomic state. As x-ray detectors, used large-area silicon drift detectors having excellent timing resolution, which were developed...
The nature of the neutral state in surface-tension driven convection is investigated by means a classical linearized stability analysis. By solving characteristic value problem numerically, it shown that, as assumed before, indeed stationary rather than an oscillatory one.
Several measurements of tree- and loop-level b-hadron decays performed in the recent years hint at a possible violation Lepton Universality. This article presents an experimental theoretical overview current status field.
Numerical solutions to the Boussinesq equations containing a temperature-dependent viscosity are presented for case of axisymmetric buoyancy-driven convective flow in cylindrical cell. Two solutions, one with upflow and other downflow at centre cell, were found each set boundary conditions that considered. The existence these two steady-state régimes was verified experimentally cell having rigid insulating lateral boundaries isothermal top bottom planes. Using perturbation expansion it is...
A model where a Dirac fermion is coupled to background dilaton field considered study s-wave scattering of by back ground black hole. It found that an uncomfortable situation towards information loss scenario arises when one loop correction gets involved during bosonization.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of Nonlinear Temperature Profiles on Onset Convection Driven by Surface Tension GradientsAntonio Vidal and Andreas AcrivosCite this: Ind. Eng. Chem. Fundamen. 1968, 7, 1, 53–58Publication Date (Print):February 1968Publication History Published online1 May 2002Published inissue 1 February 1968https://pubs.acs.org/doi/10.1021/i160025a010https://doi.org/10.1021/i160025a010research-articleACS PublicationsRequest reuse permissionsArticle...
The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and significantly improved the precision on its lifetime determination. From sample 21227 atomic pairs, 4% measurement S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ been attained, providing an important test Chiral Perturbation Theory.
The kaonic (3)He and (4)He X-rays emitted in the [Formula: see text] transitions were measured SIDDHARTA experiment. widths of 2p states determined to be text], respectively. Both results are consistent with theoretical predictions. width is much smaller than value by experiments performed 70's 80's, while was for first time.
The effect of uniform rotation on surface-tension-driven convection in an evaporating fluid layer is considered both theoretically and experimentally. theoretical analysis follows the usual small-disturbance approach perturbation theory leads, at neutral state, to a functional relation between Marangoni Taylor numbers which then computed numerically. In addition, it shown analytically that, limit rapid rotation, velocity temperature fluctuations are confined thin Ekman near surface, that M c...
To search for an |${\rm S} = -1$| di-baryonic state which decays to |$\Lambda p$|, the |${}^3{\rm He}(K^-,\Lambda p)n_{\rm missing}$| reaction was studied at 1.0 GeV}/c$|. Unobserved neutrons were kinematically identified from missing mass |$M_{X}$| of p)X$| in order have a large acceptance pn$| final state. The observed events, distributed widely over allowed region Dalitz plot, establish that major component comes three-nucleon absorption process. A concentration events specific neutron...
In this paper, we discuss the recent finalized analyses by KLOE experiment at DAΦNE: CPT and Lorentz invariance test with entangled K 0 K0 pairs, precision measurement of branching fraction decay + → π -π (γ).We also present status an ongoing analysis aiming to precisely measure ± mass.
An experiment to search for the $K^-pp$ bound state was performed via in-flight $^3$He($K^-,n)$ reaction using 5.3 $\times$ $10^9$ kaons at 1 GeV/$c$ J-PARC hadron experimental facility. In semi-inclusive neutron missing-mass spectrum $\theta_{n}^{lab}=0^\circ$, no significant peak observed in region corresponding binding energy larger than 80 MeV, where a bump structure has been reported $\Lambda p$ final different reactions. Assuming be isotropically decaying into p$, mass-dependent upper...
The results of a search for hydrogen-like atoms consisting $\pi^{\mp}K^{\pm}$ mesons are presented. Evidence $\pi K$ atom production by 24 GeV/c protons from CERN PS interacting with nickel target has been seen in terms characteristic pairs their breakup the same ($178 \pm 49$) and Coulomb final state interaction ($653 42$). Using these analysis yields first value lifetime $\tau=(2.5_{-1.8}^{+3.0})$ fs model-independent measurement S-wave isospin-odd scattering length...
A new spectrometer system has been designed and constructed at the secondary beam line K1.8BR in hadron hall of J-PARC to investigate |$\bar {K} N$| interactions {K}$|-nuclear bound systems. The consists a high precision spectrometer, liquid 3He/4He/D2 target system, cylindrical detector that surrounds detect decay particles from region, neutron time-of-flight counter array located ∼15 m downstream position. Details design, construction, performance components are described.
One of the fundamental rules nature and a pillar in foundation quantum theory thus modern physics is represented by Pauli Exclusion Principle. We know that this principle extremely well fulfilled due to many observations. Numerous experiments were performed search for tiny violation rule various systems. The experiment VIP at Gran Sasso underground laboratory searching possible small violations Principle electrons leading forbidden X-ray transitions copper atoms. aiming test with high...
The Pauli exclusion principle (PEP), consequence of the spin-statistics connection, is one basic principles modern physics. Being at very basis our understanding matter, as many other fundamental it spurs a lively debate on its possible limits, deeply rooted in foundations Quantum Field Theory. Therefore, extremely important to test limits validity. Quon theory provides suitable mathematical framework violation PEP, where parameter q translates into probability violating PEP. VIP (VIolation...
The observation of hydrogenlike πK atoms, consisting π^{-}K^{+} or π^{+}K^{-} mesons, is presented. atoms are produced by 24 GeV/c protons from the CERN PS accelerator, interacting with platinum nickel foil targets. breakup (ionization) in same targets yields characteristic pairs, called "atomic pairs," small relative momenta Q pair center-of-mass system. upgraded DIRAC experiment observed 349±62 such atomic corresponding to a signal 5.6 standard deviations. This first statistically...
After observing and investigating the double-exotic (a atom is a bound system, in which both oppositely charged components are unstable particles like μ,π,K,…) π+π− with ground state lifetime τ of about 3×10−15 s, upgraded DIRAC experiment at CERN PS accelerator observes for first time long-lived states same lifetimes 10−11 s more. The number characteristic pion pairs resulting from breakup (ionisation) atoms amounts to 436±61, corresponding signal-to-error ratio better than 7 standard...
In this paper, we discuss the recent finalized analyses by KLOE experiment at DAΦNE: CPT and Lorentz invariance test with entangled K 0 K0 pairs, precision measurement of branching fraction decay + → π -π (γ).We also present status an ongoing analysis aiming to precisely measure ± mass.