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The sensitivity of Impact Factors (IFs) to journal size causes systematic bias in IF rankings, in a process akin to {\it stacking the cards}: A random ``journal'' of $n$ papers can attain a range of IF values that decreases rapidly with size, as $\sim 1/\sqrt{n}$ . The Central Limit Theorem, which underlies this effect, also allows us to correct it by standardizing citation averages for scale {\it and} subject in a geometrically intuitive manner analogous to calculating the $z$-score. We thus propose the $\Phi$ index, a standardized scale- and subject-independent citation average. The $\Phi$ index passes the ``random sample test'', a simple check for scale and subject independence that we argue ought to be used for every citation indicator. We present $\Phi$ index rankings for 12,173 journals using 2020 Journal Citation Reports data. We show how scale standardization alone affects rankings, demonstrate the additional effect of subject standardization for monodisciplinary journals, and discuss how to treat multidisciplinary journals. $\Phi$ index rankings offer a clear improvement over IF rankings. And because the $\Phi$ index methodology is general, it can also be applied to compare individual researchers, universities, or countries., Comment: 22 pages, 10 figures, 7 tables

A degree one element of the Orlik-Solomon algebra of a hyperplane arrangement defines a cochain complex known as the Aomoto complex. The Aomoto complex can be considerd as the ``linear approximation'' of the twisted cochain complex with coefficients in a complex rank one local system. In this paper, we discuss $q$-deformations of the Aomoto complex. The $q$-deformation is defined by replacing the entries of representation matrices of the coboundary maps with their $q$-analogues. While the resulting maps do not generally define cochain complexes, for certain special basis derived from real structures, the $q$-deformation becomes again a cochain complex. Moreover, it exhibits universality in the sense that any specialization of $q$ to a complex number yields the cochain complex computing the corresponding local system cohomology group., Comment: 17 pages, 4 figures

We study two-site deconstructions of the $SU(2)_L$ gauge group factor of the SM. Models based on this approach can explain the hierarchies of the quark masses and CKM mixing between third and light families if these fields are localised on different sites by the presence of hierarchical new physics scales. The model leads to an accidental global $U(2)_q\times U(3)_u\times U(3)_d$ flavour symmetry which prevents dangerously large effects in flavour observables, making a TeV extension of the SM possible. Given the structure of the PMNS matrix in the neutrino sector, we explore different possibilities for the arrangement of the leptons on the two sites, and consider different models with $U(2)_{\ell}$ or $U(3)_{\ell}$ flavour symmetries. The phenomenology of the models is mostly governed by a massive vector triplet of $SU(2)_L$. We study the interesting interplay between LHC searches and precision observables. In particular, one of the models can give a sizeable lepton flavour universal effect in the Wilson coefficient $C_9$ while naturally suppressing contributions to $C_{10}$, as suggested by current $b\to s\ell^+\ell^-$ data, predicting simultaneously a mild positive shift in the $W$ boson mass., Comment: 11 pages + appendices, 2 figures. Section IV.E, Appendix F and references added. Version submitted for publication

General $U(1)$ extension of the Standard Model (SM) is a well motivated beyond the Standard Model(BSM) scenario where three generations of right handed neutrinos (RHNs) are introduced to cancel gauge and mixed gauge-gravity anomalies. After the $U(1)_X$ is broken, RHNs participate in the seesaw mechanism to generate light neutrino masses satisfying neutrino oscillation data. In addition to that, a neutral gauge boson $Z^\prime$ is evolved which interacts with the left and right handed fermions differently manifesting chiral nature of the model which could be probed in future collider experiments. As a result, if we consider $\mu^+ e^-$ and $\mu^+ \mu^+$ collisions in $\mu$TRISTAN experiment $Z^\prime$ mediated $2\to2$ scattering will appear in $t-$ and $u-$channels depending on the initial and final states being accompanied by the photon and $Z$ mediated interactions. This will result well motivated resulting forward dominant scenarios giving rise to sizable left-right asymmetry. Estimating constrains on general $U(1)$ coupling from LEP-II and LHC for different $U(1)_X$ charges, we calculate differential and integrated scattering cross section and left-right asymmetry for $\mu^+ e^- \to \mu^+ e^-$ and $\mu^+ \mu^+ \to \mu^+ \mu^+$ processes which could be probed at $\mu$TRISTAN experiment further enlightening the interaction between $Z^\prime$ and charged leptons and the $U(1)_X$ breaking scale., Comment: 18 pages

Recent advances in ultrafast electron emission, microscopy, and diffraction reveal our capacity to manipulate free electrons with remarkable quantum coherence using light beams. Here, we present a framework for exploring free electron fractional charge in ultrafast electron-light interactions. An explicit Jackiw-Rebbi solution of free electron is constructed by a spatiotemporally twisted laser field, showcasing a flying topological quantum number with a fractional charge of e/2 (we call it "half-electron"), which is dispersion-free due to its topological nature. We also propose an Aharonov-Bohm interferometry for detecting these half-electrons. The half-electron is a topologically protected bound state in free-space propagation, expands its realm beyond quasiparticles with fractional charges in materials, enabling to advance our understanding of exotic quantum and topological effects of free electron wavefunction., Comment: 23 pages, 4 figures, supplementary material

High-frequency wideband cellular communications over mmWave and sub-THz offer the opportunity for high data rates. However, it also presents high path loss, resulting in limited coverage. High-gain beamforming brought by the antenna array is essential to mitigate the coverage limitations. The conventional phased antenna arrays (PAA) cause high scheduling latency owing to analog beam constraints, i.e., only one frequency-flat beam is generated. Recently introduced joint phase-time array (JPTA) architecture, which utilizes both true-time-delay (TTD) units and phase shifters (PSs), alleviates analog beam constraints by creating multiple frequency-dependent beams for scheduling multiple users at different directions in a frequency-division manner. One class of previous studies offered solutions with "rainbow" beams, which tend to allocate a small bandwidth per beam direction. Another class focused on uniform linear array (ULA) antenna architecture, whose frequency-dependent beams were designed along a single axis of either azimuth or elevation direction. This paper presents a novel 3D beamforming design that maximizes beamforming gain toward desired azimuth and elevation directions and across sub-bands partitioned according to scheduled users' bandwidth requirements. We provide analytical solutions and iterative algorithms to design the PSs and TTD units for a desired subband beam pattern. Through simulations of the beamforming gain, we observe that our proposed solutions outperform the state-of-the-art solutions reported elsewhere.

The chemical compositions of stars encode the history of the universe and are thus fundamental for advancing our knowledge of astrophysics and cosmology. However, measurements of elemental abundances ratios, and our interpretations of them, strongly depend on the physical assumptions that dictate the generation of synthetic stellar spectra. Three-dimensional radiation-hydrodynamic (3D RHD) ``box-in-a-star'' simulations of stellar atmospheres offer a more realistic representation of surface convection occurring in late-type stars compared to traditional one-dimensional (1D) hydrostatic models. As evident from a multitude of observational tests, the coupling of 3D RHD models with line-formation in non-local thermodynamic equilibrium (non-LTE) today provides a solid foundation for abundance analysis for many elements. This review describes the ongoing and transformational work to advance the state-of-the-art and replace 1D LTE spectrum synthesis with its 3D non-LTE counterpart. In summary: 1) 3D and non-LTE effects are intricately coupled and consistent modelling thereof is necessary for high-precision abundances, which is currently feasible for individual elements in large surveys. Mean 3D (<3D>) models are not adequate as substitutes. 2) The solar abundance debate is presently dominated by choices and systematic uncertainties that are not specific to 3D non-LTE modelling. 3) 3D non-LTE abundance corrections have a profound impact on our understanding of FGK-type stars, exoplanets, and the nucleosynthetic origins of the elements., Comment: To appear in Annual Reviews of Astronomy and Astrophysics (65 pages, 13 figures)