To achieve high precision in phenomenological studies and to uncover novel physics at collider experiments, it is essential to determine the flavour of reconstructed hadronic jets. This enables the identification of distinct scattering processes and the elimination of interfering background events. The anti-k_T algorithm, prevalent in jet measurements at the LHC, currently lacks a procedure for defining jet flavor that respects infrared and collinear safety constraints. We introduce a new flavor-dressing algorithm, safe in infrared and collinear limits of perturbation theory, which can be combined with any jet definition. Using an e^+e^- collision framework, the algorithm's capabilities are evaluated in the context of the ppZ+b-jet process, a practical illustration relevant for hadron collider experiments.
We introduce a suite of entanglement witnesses applicable to continuous variable systems, whose operation rests entirely on the assumption that the system's interactions during the test are governed by coupled harmonic oscillators. Entanglement in one normal mode is suggested by the Tsirelson nonclassicality test, wholly independent of the other mode's unknown state. The protocol, during each round, specifies the measurement of just the sign of one coordinate (like position) at a specific point in time out of a selection of possibilities. Selleck SW-100 The dynamic-based entanglement witness, more closely resembling a Bell inequality than an uncertainty relation, avoids false alarms that might originate from classical interpretations. Our criterion's distinctive feature is its ability to find non-Gaussian states, a significant strength in contrast to other, less comprehensive criteria.
A thorough understanding of the full quantum dynamics of molecules and materials crucially relies on accurately depicting the correlated quantum motions of electrons and nuclei. A new methodology for simulating nonadiabatic coupled electron-nuclear quantum dynamics with electronic transitions has been developed, leveraging the Ehrenfest theorem and ring polymer molecular dynamics. Employing the isomorphic ring polymer Hamiltonian, time-dependent multistate electronic Schrödinger equations are solved self-consistently using approximate equations of motion for nuclei. Each bead's motion is guided by its individual electronic configuration, thereby causing it to move on a specific effective potential. Employing an independent-bead approach, a precise account of real-time electronic population and quantum nuclear trajectory is furnished, aligning well with the exact quantum solution. First-principles calculations allow us to model photoinduced proton transfer in H2O-H2O+, yielding results consistent with experimental observations.
Despite its significant mass fraction within the Milky Way disk, cold gas poses the greatest uncertainty among its baryonic components. The density and distribution of cold gas are of critical importance in the context of Milky Way dynamics, and are essential components in models of stellar and galactic evolution. Correlations between gas and dust, a method frequently used in previous studies for acquiring high-resolution measurements of cold gas, are nonetheless often subject to substantial normalization errors. We introduce a new approach to estimate total gas density, based on Fermi-LAT -ray data, achieving comparable accuracy to previous studies, but with independently derived systematic errors. Our results demonstrate impressive precision, allowing for an examination of the full range of outcomes produced by currently top-performing experimental research globally.
Our letter showcases the potential of combining quantum metrology and networking techniques to lengthen the baseline of an interferometric optical telescope, leading to enhanced diffraction-limited imaging capabilities for point source positions. A quantum interferometer is comprised of single-photon sources, linear optical circuits, and advanced photon number counters for its operation. The detected photon probability distribution, surprisingly, retains a significant amount of Fisher information about the source's position, despite the low photon number per mode from thermal (stellar) sources and substantial transmission losses along the baseline, leading to a considerable enhancement in the resolution of point source positioning, approximately on the order of 10 arcseconds. Our proposal is demonstrably implementable with the technology that is currently available. Importantly, our plan does not call for the development of experimental optical quantum memories.
Based on the principle of maximum entropy, we propose a comprehensive technique for suppressing fluctuations observed in heavy-ion collisions. The results reveal a clear and direct relationship between the irreducible relative correlators that quantify the deviations of hydrodynamic and hadron gas fluctuations from the ideal hadron gas standard. This method, based on the QCD equation of state, permits the determination of previously uncharted parameters necessary for characterizing the freeze-out of fluctuations near the QCD critical point.
We investigate the thermophoresis of polystyrene beads, spanning a range of temperature gradients, and find a pronounced nonlinear phoretic behavior. The nonlinear behavior threshold is marked by a substantial slowing of thermophoretic motion, with the Peclet number observed to be in the vicinity of unity across various particle sizes and salt solutions. Across all system parameters, the data demonstrate a singular master curve encompassing the entire nonlinear regime once temperature gradients are rescaled with the Peclet number. In scenarios with mild temperature changes, the rate of thermal movement aligns with a theoretical linear model, predicated on the local thermal equilibrium principle, whereas theoretical linear models, founded on hydrodynamic stresses and disregarding fluctuations, project a notably reduced thermophoretic velocity in cases of pronounced temperature differences. The thermophoretic effects we observed demonstrate a fluctuation-driven nature for minor gradients, shifting to a drift-dependent process with increasing Peclet numbers, notably contrasting with electrophoresis.
Nuclear fusion processes are central to a diverse array of astrophysical stellar transients, encompassing thermonuclear, pair-instability, and core-collapse supernovae, alongside kilonovae and collapsars. The role of turbulence in these astrophysical transients is now better appreciated. This research demonstrates that turbulent nuclear burning rates can be dramatically higher than the uniform background, due to temperature fluctuations that originate from turbulent dissipation. Nuclear burning rates are sensitive to temperature fluctuations. In homogeneous, isotropic turbulence, we utilize probability distribution function methods to ascertain the turbulent escalation of the nuclear burning rate during distributed burning, under the impact of strong turbulence. We find that the turbulent intensification adheres to a universal scaling law under conditions of weak turbulence. Our further demonstration reveals that, for a broad array of key nuclear reactions, like C^12(O^16,)Mg^24 and 3-, even comparatively slight temperature fluctuations, around 10%, can result in enhancements of the turbulent nuclear burning rate by factors of 1 to 3 orders of magnitude. Numerical simulations directly corroborate the predicted increase in turbulent activity, demonstrating exceptional agreement. We also propose an estimation of the moment turbulent detonation ignition commences, and discuss the bearing of our conclusions upon stellar transients.
Semiconducting behavior is a sought-after property in the ongoing pursuit of efficient thermoelectric materials. Nevertheless, the realization of this is often complicated by the intricate interplay of electronic structure, temperature, and imperfections in the system. AhR-mediated toxicity In the thermoelectric clathrate Ba8Al16Si30, this observation holds true. Although its ground state possesses a band gap, a temperature-driven partial order-disorder transition causes this gap to effectively vanish. A novel approach to calculating the temperature-dependent effective band structure of alloys enables this finding. The effects of short-range order are entirely taken into account by our method, allowing for its application to complex alloys with a multitude of atoms in the primitive cell without resorting to effective medium approximations.
Employing discrete element method simulations, we establish that the settling behavior of frictional, cohesive grains under ramped-pressure compression displays a strong history dependence and slow dynamic behavior that is conspicuously absent in grains without either frictional or cohesive properties. Systems starting from a dilute phase, subjected to a controlled pressure ramp up to a small positive final pressure P, achieve packing fractions following an inverse logarithmic rate law, with settled(ramp) = settled() + A / [1 + B ln(1 + ramp / slow)]. This law, while bearing resemblance to those established through classical tapping experiments on granular materials lacking cohesion, differs significantly. Its timing is dictated by the slow consolidation of structural voids, instead of the faster densification occurring throughout the bulk material. A kinetic free-void-volume model is formulated to predict the settled(ramp) state. This model establishes a relationship where settled() equals ALP, and A is determined as the difference between settled(0) and ALP. Essential to this model is the adhesive loose packing fraction, ALP.135, identified by Liu et al. (Equation of state for random sphere packings with arbitrary adhesion and friction, Soft Matter 13, 421 (2017)).
Ultrapure ferromagnetic insulators are now the subject of recent experimentation, which demonstrates a hint of hydrodynamic magnon behavior, yet direct observation remains unfulfilled. In this study, coupled hydrodynamic equations are derived, with a focus on the thermal and spin conductivities of a magnon fluid. The hydrodynamic regime's signature is the pronounced breakdown of the magnonic Wiedemann-Franz law, providing essential proof for the experimental realization of emergent hydrodynamic magnon behavior. Accordingly, our data points the way toward the direct observation of magnon liquids.