We present the first joint analysis of cluster abundances and auto or cross-correlations of three cosmic tracer fields: galaxy density, weak gravitational lensing shear, and cluster density split by ...optical richness. From a joint analysis (4×2pt+N) of cluster abundances, three cluster cross-correlations, and the auto correlations of the galaxy density measured from the first year data of the Dark Energy Survey, we obtain Ω_{m}=0.305_{-0.038}^{+0.055} and σ_{8}=0.783_{-0.054}^{+0.064}. This result is consistent with constraints from the DES-Y1 galaxy clustering and weak lensing two-point correlation functions for the flat νΛCDM model. Consequently, we combine cluster abundances and all two-point correlations from across all three cosmic tracer fields (6×2pt+N) and find improved constraints on cosmological parameters as well as on the cluster observable-mass scaling relation. This analysis is an important advance in both optical cluster cosmology and multiprobe analyses of upcoming wide imaging surveys.
Review of Particle Physics Workman, R L; Klempt, E; Agashe, K ...
Progress of theoretical and experimental physics,
08/2022, Letnik:
2022, Številka:
8
Journal Article
Recenzirano
Odprti dostop
Abstract
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured ...properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, Probability and Statistics. Among the 120 reviews are many that are new or heavily revised, including a new review on Machine Learning, and one on Spectroscopy of Light Meson Resonances.
The Review is divided into two volumes. Volume 1 includes the Summary Tables and 97 review articles. Volume 2 consists of the Particle Listings and contains also 23 reviews that address specific aspects of the data presented in the Listings.
The complete Review (both volumes) is published online on the website of the Particle Data Group (pdg.lbl.gov) and in a journal. Volume 1 is available in print as the PDG Book. A Particle Physics Booklet with the Summary Tables and essential tables, figures, and equations from selected review articles is available in print, as a web version optimized for use on phones, and as an Android app.
We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two ...independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10^{-39} cm^{2}-consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.
We present the first demonstration of THz driven bunch compression and timing stabilization of a relativistic electron beam. Quasi-single-cycle strong field THz radiation is used in a shorted ...parallel-plate structure to compress a few-fC beam with 2.5 MeV kinetic energy by a factor of 2.7, producing a 39 fs rms bunch length and a reduction in timing jitter by more than a factor of 2 to 31 fs rms. This THz driven technique offers a significant improvement to beam performance for applications like ultrafast electron diffraction, providing a critical step towards unprecedented timing resolution in ultrafast sciences, and other accelerator applications using femtosecond-scale electron beams.
Key insights into the behavior of materials can be gained by observing their structure as they undergo lattice distortion. Laser pulses on the femtosecond time scale can be used to induce disorder in ...a "pump-probe" experiment with the ensuing transients being probed stroboscopically with femtosecond pulses of visible light, x-rays, or electrons. Here we report three-dimensional imaging of the generation and subsequent evolution of coherent acoustic phonons on the picosecond time scale within a single gold nanocrystal by means of an x-ray free-electron laser, providing insights into the physics of this phenomenon. Our results allow comparison and confirmation of predictive models based on continuum elasticity theory and molecular dynamics simulations.
When two sheets of graphene are stacked at a small twist angle, the resulting flat superlattice minibands are expected to strongly enhance electron-electron interactions. Here, we present evidence ...that near three-quarters (Formula: see text) filling of the conduction miniband, these enhanced interactions drive the twisted bilayer graphene into a ferromagnetic state. In a narrow density range around an apparent insulating state at Formula: see text, we observe emergent ferromagnetic hysteresis, with a giant anomalous Hall (AH) effect as large as 10.4 kilohms and indications of chiral edge states. Notably, the magnetization of the sample can be reversed by applying a small direct current. Although the AH resistance is not quantized, and dissipation is present, our measurements suggest that the system may be an incipient Chern insulator.
We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multiwavelength reverberation mapping campaign. The campaign spanned 6 months and achieved ...an almost daily cadence with observations from five ground-based telescopes. The Hβ and He ii λ4686 broad emission-line light curves lag that of the 5100 optical continuum by and , respectively. The Hβ lag relative to the 1158 ultraviolet continuum light curve measured by the Hubble Space Telescope is ∼50% longer than that measured against the optical continuum, and the lag difference is consistent with the observed lag between the optical and ultraviolet continua. This suggests that the characteristic radius of the broad-line region is ∼50% larger than the value inferred from optical data alone. We also measured velocity-resolved emission-line lags for Hβ and found a complex velocity-lag structure with shorter lags in the line wings, indicative of a broad-line region dominated by Keplerian motion. The responses of both the Hβ and He ii emission lines to the driving continuum changed significantly halfway through the campaign, a phenomenon also observed for C iv, Ly , He ii(+O iii), and Si iv(+O iv) during the same monitoring period. Finally, given the optical luminosity of NGC 5548 during our campaign, the measured Hβ lag is a factor of five shorter than the expected value implied by the RBLR-LAGN relation based on the past behavior of NGC 5548.
By considering radiative corrections of up to 3rd-loop order, Ritus and Narozhny conjectured that the proper expansion parameter for QED in a strong constant crossed field is g = αχ2/3, where the ...dynamical quantum parameter χ = e√−(Fp)2/m3 combines the particle momentum p with the external field strength tensor F . Here we present and discuss the first nonperturbative result in this context, the resummed bubble-type polarization corrections to the electron self-energy in a constant crossed field. Our analysis confirms the relevance of the scaling parameter g to the enhancement of bubble-type radiative corrections. This parameter actually represents the characteristic value of the ratio of the 1-loop polarization bubble to the photon virtuality. After an all-order resummation we identify and discuss two contributions to the self-energy with different formation regions and asymptotic behavior for g ≫ 1. Whereas the breakdown of perturbation theory occurs already for g ≳ 1, the leading-order result remains dominant until the asymptotic regime g ≫ 1 is reached. However, the latter is specific to processes like elastic scattering or photon emission and does not have to remain true for general higher-order QED processes.
Tunnelling is one of the most fundamental manifestations of quantum mechanics. The recent advent of lightwave-driven scanning tunnelling microscopy has revolutionized ultrafast nanoscience by ...directly resolving electron tunnelling in electrically conducting samples on the relevant ultrashort length- and timescales. Here, we introduce a complementary approach based on terahertz near-field microscopy to perform ultrafast nano-videography of tunnelling processes even in insulators. The central idea is to probe the evolution of the local polarizability of electron–hole pairs with evanescent terahertz fields, which we detect with subcycle temporal resolution. In a proof of concept, we resolve femtosecond interlayer transport in van der Waals heterobilayers and reveal pronounced variations of the local formation and annihilation of interlayer excitons on deeply subwavelength, nanometre scales. Such contact-free nanoscopy of tunnelling-induced dynamics should be universally applicable to conducting and non-conducting samples and reveal how ultrafast transport processes shape functionalities in a wide range of condensed matter systems.Subcycle nano-videography of charge-transfer dynamics in WSe2/WS2 heterostructures is obtained by using a terahertz near-field microscopy. The central idea is to probe the local polarizability of electron–hole pairs with evanescent terahertz fields.
Shear peak statistics has gained a lot of attention recently as a practical alternative to the two-point statistics for constraining cosmological parameters. We perform a shear peak statistics ...analysis of the Dark Energy Survey (DES) Science Verification (SV) data, using weak gravitational lensing measurements from a 139 deg super( 2) field. We measure the abundance of peaks identified in aperture mass maps, as a function of their signal-to-noise ratio, in the signal-to-noise range ... To predict the peak counts as a function of cosmological parameters, we use a suite of N-body simulations spanning 158 models with varying ... and ..., fixing ..., to which we have applied the DES SV mask and redshift distribution. In our fiducial analysis we measure ..., after marginalizing over the shear multiplicative bias and the error on the mean redshift of the galaxy sample. We introduce models of intrinsic alignments, blending and source contamination by cluster members. These models indicate that peaks with ... would require significant corrections, which is why we do not include them in our analysis. We compare our results to the cosmological constraints from the two-point analysis on the SV field and find them to be in good agreement in both the central value and its uncertainty. We discuss prospects for future peak statistics analysis with upcoming DES data. (ProQuest: ... denotes formulae/symbols omitted.)
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