7,206 research outputs found
Distinguishing between Dirac and Majorana neutrinos with two-particle interferometry
Two-particle interferometry, a second-order interference effect, is explored
as another possible tool to distinguish between massive Dirac and Majorana
neutrinos. A simple theoretical framework is discussed in the context of
several gedanken experiments. The method can in principle provide both the mass
scale and the quantum nature of the neutrino for a certain class of incoherent
left-handed source currents.Comment: 4 pages, 1 table, submitted to PRL; changes to introduction and added
discussio
Leading charm in hadron-nucleus interactions in the intrinsic charm model
Leading charm hadrons produced in hadron-nucleus interactions cannot be adequately described within the parton fusion model. Recent results on charm baryon production in ∑-A interactions at 330 GeV with the WA89 detector disagree with fusion predictions. Intrinsic heavy quark pairs in the ∑- (dds) wavefunction provide a simple mechanism for producing fast charm hadrons. We calculate leading charm baryon production from ∑-, ∏- and p projectiles in a two component model combining parton fusion with intrinsic charm. Final state D-, ∑ncn0, ≡ncn+, and ∧ncn+ dσ/dxnF distributions and D-/D +, DT/D + and A+~/-A+~ asymmetries are compared to WA89 data. Predictions are made for 650 GeV ∑-A and ∏-A interactions in the SELEX detector at Fermilab and for 800 GeV pA interactions
Incident energy dependence of p\u3csub\u3et\u3c/sub\u3e correlations at relativistic energies
We present results for two-particle transverse momentum correlations, ⟨Δpt,iΔpt,j⟩, as a function of event centrality for Au+Au collisions at √sNN=20, 62, 130, and 200 GeV at the BNL Relativistic Heavy Ion Collider. We observe correlations decreasing with centrality that are similar at all four incident energies. The correlations multiplied by the multiplicity density increase with incident energy, and the centrality dependence may show evidence of processes such as thermalization, jet production, or the saturation of transverse flow. The square root of the correlations divided by the event-wise average transverse momentum per event shows little or no beam energy dependence and generally agrees with previous measurements made at the CERN Super Proton Synchrotron
An Introduction to the Inverse Quantum Bound State Problem in One Dimension
A technique to reconstruct one-dimensional, reflectionless potentials and the
associated quantum wave functions starting from a finite number of known energy
spectra is discussed. The method is demonstrated using spectra that scale like
the lowest energy states of standard problems encountered in the undergraduate
curriculum such as: the infinite square well, the simple harmonic oscillator,
and the one-dimensional hydrogen atom.Comment: 10 pages, 10 figures, Submitted to Am. J. Phys. August 201
Recent Advances on Iron Oxide Magnetic Nanoparticles as Sorbents of Organic Pollutants in Water and Wastewater Treatment
The constant growth in population worldwide over the past decades continues to put forward the need to provide access to safe, clean water to meet human needs. There is a need for cost-effective technologies for water and wastewater treatment that can meet the global demands and the rigorous water quality standards and at the same maximizing pollutant efficiency removal. Current remediation technologies have failed in keeping up with these factors without becoming cost-prohibitive. Most recently, nanotechnology has been sought as the best alternative to increase access to water supplies by remediating those already contaminated and offering ways to access unconventional sources. The use of iron oxide magnetic nanoparticles as nanoadsorbents has led way to a new class of magnetic separation strategies for water treatment. This review focuses on highlighting some of the most recent advances in core-shell iron oxide magnetic nanoparticles and nanocomposites containing iron oxide nanoparticles currently being developed for water and wastewater treatment of organic pollutants. We discuss the novelty of these novel materials and the insight gained from their advances that can help develop cost-effective reusable technologies for scale-up and commercial use
Real-time insight into the multistage mechanism of nanoparticle exsolution from a perovskite host surface
In exsolution, nanoparticles form by emerging from oxide hosts by application of redox driving forces, leading to transformative advances in stability, activity, and efficiency over deposition techniques, and resulting in a wide range of new opportunities for catalytic, energy and net-zero-related technologies. However, the mechanism of exsolved nanoparticle nucleation and perovskite structural evolution, has, to date, remained unclear. Herein, we shed light on this elusive process by following in real time Ir nanoparticle emergence from a SrTiO3 host oxide lattice, using in situ high-resolution electron microscopy in combination with computational simulations and machine learning analytics. We show that nucleation occurs via atom clustering, in tandem with host evolution, revealing the participation of surface defects and host lattice restructuring in trapping Ir atoms to initiate nanoparticle formation and growth. These insights provide a theoretical platform and practical recommendations to further the development of highly functional and broadly applicable exsolvable materials
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