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Simple form scalar differential equation with delay and nonlinear negative periodic feedback is considered. The existence of several types of slowly oscillating periodic solutions is shown with the same and double periods of the feedback coefficient. The periodic solutions are built explicitly in the case of piecewise constant nonlinearities involved. The periodic dynamics are shown to persist under small perturbations of the equation which make it smooth. The theoretical results are verified by extensive numerical simulations.

The article is devoted to the study of diagonal digraphs, i.e. digraphs whose magnitude homology is concentrated on the diagonal. For a digraph $G$ and $\ell\geq 2,$ we describe a condition, denoted by $(\mathcal{V}_\ell)$, equivalent to vanishing of the second magnitude homology group ${\rm MH}_{2,k}(G,\mathbb{Z})$ for all $k>\ell.$ In particular, diagonal digraphs satisfy $(\mathcal{V}_2).$ As a corollary we obtain that the 2-dimensional CW-complex obtained from a diagonal undirected graph by attaching 2-cells to all squares and triangles of the graph is simply connected. We also give an interpretation of diagonality in terms of Koszul algebras: a digraph $G$ is diagonal if and only if the distance algebra $\sigma G$ is Koszul for any ground field; and if and only if $G$ satisfies $(\mathcal{V}_2)$ and the path cochain algebra $\Omega^\bullet(G)$ is Koszul for any ground field. To obtain a source of examples of digraphs, we study the extended Hasse diagram $\hat G_K$ of a pure simplicial complex $K$. For a triangulation $K$ of a topological manifold $M,$ we express the non-diagonal part of the magnitude homology of $\hat G_K$ via the homology of $M$. As a corollary we obtain that, if $K$ is a triangulation of a closed manifold $M$, then $\hat G_K$ is diagonal if and only if $M$ is a homology sphere.

Cavity-free lasing in atmospheric air has stimulated intense research towards fundamental understanding of underlying physical mechanisms. In this Letter, we identify a new mechanism -- third harmonic photon mediated resonant energy transfer pathway leading to population inversion in argon via initial three-photon excitation of nitrogen molecules irradiated by intense 261 nm pulses -- that enables bidirectional two-color cascaded lasing in atmospheric air. By making pump-probe measurements, we conclusively show that such cascaded lasing results from superfluorescence (SF) rather than amplified spontaneous emission (ASE). Such cascaded lasing with the capability of producing bidirectional multicolor coherent pulses opens additional possibilities for remote sensing applications., Comment: 4 figures

In this paper, we study operations on functors in the category of abelian groups simplar to the derivation in the sense of Dold-Puppe. They are defined as derived limits of a functor applied to the relation subgroup over a category of free presentations of the group. The integral homology of the Eilenberg-Maclane space $K(\mathbb Z,3)$ appears as a part of description of these operations applied to symmetric powers.

Scaling spectral broadening to higher pulse energies and average powers, respectively, is a critical step in ultrafast science, especially for narrowband Yb based solid state lasers which become the new state of the art. Despite their high nonlinearity, molecular gases as the broadening medium inside hollow core fibers have been limited to 25 W, at best. We demonstrate spectral broadening in nitrogen at ten-fold average powers up to 250W with repetition rates from 25 to 200kHz. The observed ten-fold spectral broadening is stronger compared to the more expensive krypton gas and enables pulse compression from 1.3ps to 120fs. We identified an intuitive explanation for the observed average power scaling based on the density of molecular ro vibrational states of Raman active molecules. To verify this ansatz, spectral broadening limitations in O2 and N2O are experimentally measured and agree well. On these grounds we propose a new perspective on the role, suitability, and limits of stimulated Raman scattering at high average and peak powers. Finally, high harmonic generation is demonstrated at 200 kHz.

The last few years have seen the emergence of a wide array of novel techniques for analyzing high-precision data from upcoming galaxy surveys, which aim to extend the statistical analysis of galaxy clustering data beyond the linear regime and the canonical two-point (2pt) statistics. We test and benchmark some of these new techniques in a community data challenge "Beyond-2pt", initiated during the Aspen 2022 Summer Program "Large-Scale Structure Cosmology beyond 2-Point Statistics," whose first round of results we present here. The challenge dataset consists of high-precision mock galaxy catalogs for clustering in real space, redshift space, and on a light cone. Participants in the challenge have developed end-to-end pipelines to analyze mock catalogs and extract unknown ("masked") cosmological parameters of the underlying $\Lambda$CDM models with their methods. The methods represented are density-split clustering, nearest neighbor statistics, BACCO power spectrum emulator, void statistics, LEFTfield field-level inference using effective field theory (EFT), and joint power spectrum and bispectrum analyses using both EFT and simulation-based inference. In this work, we review the results of the challenge, focusing on problems solved, lessons learned, and future research needed to perfect the emerging beyond-2pt approaches. The unbiased parameter recovery demonstrated in this challenge by multiple statistics and the associated modeling and inference frameworks supports the credibility of cosmology constraints from these methods. The challenge data set is publicly available and we welcome future submissions from methods that are not yet represented., Comment: New submissions welcome! Challenge data available at https://github.com/ANSalcedo/Beyond2ptMock

The second "Mineral Detection of Neutrinos and Dark Matter" (MDvDM'24) meeting was held January 8-11, 2024 in Arlington, VA, USA, hosted by Virginia Tech's Center for Neutrino Physics. This document collects contributions from this workshop, providing an overview of activities in the field. MDvDM'24 was the second topical workshop dedicated to the emerging field of mineral detection of neutrinos and dark matter, following a meeting hosted by IFPU in Trieste, Italy in October 2022. Mineral detectors have been proposed for a wide variety of applications, including searching for dark matter, measuring various fluxes of astrophysical neutrinos over gigayear timescales, monitoring nuclear reactors, and nuclear disarmament protocols; both as paleo-detectors using natural minerals that could have recorded the traces of nuclear recoils for timescales as long as a billion years and as detectors recording nuclear recoil events on laboratory timescales using natural or artificial minerals. Contributions to this proceedings discuss the vast physics potential, the progress in experimental studies, and the numerous challenges lying ahead on the path towards mineral detection. These include a better understanding of the formation and annealing of recoil defects in crystals; identifying the best classes of minerals and, for paleo-detectors, understanding their geology; modeling and control of the relevant backgrounds; developing, combining, and scaling up imaging and data analysis techniques; and many others. During the last years, MDvDM has grown rapidly and gained attention. Small-scale experimental efforts focused on establishing various microscopic readout techniques are underway at institutions in North America, Europe and Asia. We are looking ahead to an exciting future full of challenges to overcome, surprises to be encountered, and discoveries lying ahead of us., Comment: Summary and proceedings of the MDvDM'24 conference, Jan 8-11 2024

Artificial Intelligence (AI) approaches are increasingly being applied to more and more domains of Science, Engineering, Chemistry, and Industries to not only improve efficiencies and enhance productivity, but also enable new capabilities. The new opportunities range from automated molecule design and screening, properties prediction, gaining insights of chemical reactions, to computer-aided design, predictive maintenance of systems, robotics, and autonomous vehicles. This review focuses on the new applications of AI in manufacturing and healthcare. For the Manufacturing Industries, we focus on AI and algorithms for (1) Battery, (2) Flow Chemistry, (3) Additive Manufacturing, (4) Sensors, and (5) Machine Vision. For Healthcare applications, we focus on: (1) Medical Vision (2) Diagnosis, (3) Protein Design, and (4) Drug Discovery. In the end, related topics are discussed, including physics integrated machine learning, model explainability, security, and governance during model deployment.

Starting from the assumption that saturation of plasma turbulence driven by temperature-gradient instabilities in fusion plasmas is achieved by a local energy cascade between a long-wavelength outer scale, where energy is injected into the fluctuations, and a small-wavelength dissipation scale, where fluctuation energy is thermalized by particle collisions, we formulate a detailed phenomenological theory for the influence of perpendicular flow shear on magnetized-plasma turbulence. Our theory introduces two distinct regimes, called the weak-shear and strong-shear regimes, each with its own set of scaling laws for the scale and amplitude of the fluctuations and for the level of turbulent heat transport. We discover that the ratio of the typical radial and poloidal wavenumbers of the fluctuations (i.e., their aspect ratio) at the outer scale plays a central role in determining the dependence of the turbulent transport on the imposed flow shear. Our theoretical predictions are found to be in excellent agreement with numerical simulations of two paradigmatic models of fusion-relevant plasma turbulence: (i) an electrostatic fluid model of slab electron-scale turbulence, and (ii) Cyclone-base-case gyrokinetic ion-scale turbulence. Additionally, our theory envisions a potential mechanism for the suppression of electron-scale turbulence by perpendicular ion-scale flows based on the role of the aforementioned aspect ratio of the electron-scale fluctuations., Comment: 21 pages, 13 figures, 1 table

The Spin Physics Detector collaboration proposes to install a universal detector in the second interaction point of the NICA collider under construction (JINR, Dubna) to study the spin structure of the proton and deuteron and other spin-related phenomena using a unique possibility to operate with polarized proton and deuteron beams at a collision energy up to 27 GeV and a luminosity up to $10^{32}$ cm$^{-2}$ s$^{-1}$. As the main goal, the experiment aims to provide access to the gluon TMD PDFs in the proton and deuteron, as well as the gluon transversity distribution and tensor PDFs in the deuteron, via the measurement of specific single and double spin asymmetries using different complementary probes such as charmonia, open charm, and prompt photon production processes. Other polarized and unpolarized physics is possible, especially at the first stage of NICA operation with reduced luminosity and collision energy of the proton and ion beams. This document is dedicated exclusively to technical issues of the SPD setup construction.

The ALICE experiment at CERN LHC is specifically designed for investigating heavy ion collisions. The upgraded ALICE accommodates a tenfold increase in PbPb luminosity and a two-order of magnitude surge in minimum bias events. To address the challenges of high detector occupancy and event pile-ups, advanced multidimensional data analysis techniques, including machine learning (ML), are indispensable. Despite ML popularity, the complexity of its models presents interpretation challenges, and oversimplification in analysis often leads to inaccuracies. Our objective was to develop RootInteractive, a tool for multidimensional statistical analysis. This tool simplifies data analysis across dimensions, visualizes functions with uncertainties, and validates assumptions and approximations. In RootInteractive, it is crucial to easily define the functional composition of analytical parametric and non-parametric functions, exploit symmetries, and define multidimensional invariant functions and corresponding alarms. RootInteractive adopts a declarative programming paradigm, ensuring userfriendliness for experts, students, and educators. It facilitates interactive visualization, n-dimensional histogramming/projection, and information extraction on both Python,C++ server and client. Data compression, datasets with O(10 to 7) entries and O(25) attributes can be interactively analyzed in a browser with O(0.500-1 GB) size. Representative downsampling and reweighting/pre-aggregation enable the effective analysis of one year of ALICE data for various purposes.

We construct an off-shell $\mathcal{N}=2$ superconformal cubic vertex for the hypermultiplet coupled to an arbitrary integer higher spin ${\bf s}$ gauge $\mathcal{N}=2$ supermultiplet % in flatfour-dimensional space. in a general $\mathcal{N}=2$ conformal supergravity background. We heavily use $\mathcal{N}=2, 4D$ harmonic superspace that provides an unconstrained superfield Lagrangian description. We start with $\mathcal{N}=2$ global superconformal symmetry transformations of the free hypermultiplet model and require invariance of the cubic vertices of general form under these transformations and their gauged version. As a result, we deduce $\mathcal{N}=2, 4D$ unconstrained analytic superconformal gauge potentials for an arbitrary integer ${\bf s}$. These are the basic ingredients of the approach under consideration. We describe the properties of the gauge potentials, derive the corresponding superconformal and gauge transformation laws, and inspect the off-shell contents of the thus obtained $\mathcal{N}=2$ superconformal higher-spin ${\bf s}$ multiplets in the Wess-Zumino gauges. The spin ${\bf s}$ multiplet involves $8(2{\bf s} -1)_B + 8(2{\bf s}-1)_F$ essential off-shell degrees of freedom. The cubic vertex has the generic structure higher spin gauge superfields $\times$ hypermultiplet supercurrents. We present the explicit form of the relevant supercurrents., Comment: 0 + 60 pages, many corrections without affecting the final results; published version

Quasi-stellar objects (QSOs) are a basis for an absolute reference system for astrometric studies. There is a need for creating such system behind nearby galaxies, to facilitate the measuring of the proper motions of these galaxies. However, the foreground contamination from the galaxies themselves is a problem for the QSO identification. We search for new QSOs behind both Magellanic Clouds, the Magellanic Bridge, and the Magellanic Stream. We identify QSO candidates with a combination of near-infrared colors and variability criteria from the public ESO Visual and Infrared Survey Telescope for Astronomy (VISTA) Magellanic Clouds (VMC) survey. We confirm their nature from broad emission lines with low-resolution optical spectroscopy. We confirmed the QSO nature of 136 objects. They are distributed as follows: 12 behind the LMC, 37 behind the SMC, 63 behind the Bridge, and 24 behind the Stream. The QSOs span a redshift range from z~0.1 to z~2.9. A comparison of our quasar selection with the Quaia quasar catalog, based on Gaia low-resolution spectra, yields a selection and confirmation success rate of 6-19%, depending on whether the quality of the photometry, the magnitude ranges and the colors are considered. Our candidate list is rather incomplete, but the objects in it are likely to be confirmed as quasars with ~90% probability. Finally, we report a list of 3609 objects across the entire VMC survey that match our color and variability selection criteria; only 1249 of them have Gaia counterparts. Our combined infrared color and variability criteria for QSO selection prove to be efficient - ~90% of the observed candidates are bona fide QSOs and allow to generate a list of new high-probability quasar candidates., Comment: 20 pages, 9 figures, 5 tables

We theoretically propose a type of tunable polarization retarder, which is composed of sequences of half-wave and quarter-wave polarization retarders, allowing operation at broad spectral bandwidth. The constituent retarders are composed of stacked standard half-wave retarders and quarter-wave retarders rotated at designated angles relative to their fast-polarization axes. The proposed composite retarder can be tuned to an arbitrary value of the retardance by varying the middle retarder alone, while maintaining its broadband spectral bandwidth intact.

To derive the best oscillator phase noise when implementing a high-Q resonator, the spectral line-shape must have high contrast and symmetry. Ideally, this line-shape is Lorentzian, however, in a high mode density spectral region, low-Q background spurious modes interact and distort the resonance. For a sapphire-loaded cavity resonator operating with whispering gallery modes we show that this high contrast and symmetry can be achieved by changing the dimensions of the surrounding cavity shield to tune the background low-Q structures into anti-resonance. This works because the high-Q resonances are primarily defined by the sapphire while the background modes are defined by the cavity shield. Alternatively, it was shown that a similar result can be achieved by exciting the high-Q resonator with a balanced microwave dipole probe in a Mach Zehnder interferometric configuration. The probe was constructed from two separate coaxial electric field probes symmetrically inserted into a cylindrical cavity resonator, from opposite sides with a small gap between them, so they can behave like an active wire dipole antenna. The power into the two separate probes may be matched with an external variable attenuator in one of the arms of the interferometer. Conversely, the phase between the two electric field probes may be changed with an external variable phase shifter, which changes the nature of the field components the probe couples to. The probe couples to the high-Q resonant modes as well as low-Q background modes, which can be made resonant or anti-resonant for the high-Q modes by changing this external phase. When the background modes are in anti-resonance the line shape of the high-Q mode can be made symmetric and with higher contrast. This technique was applied to both whispering gallery sapphire modes, as well as hollow cavity resonators, without changing the dimensions of the cavity., Comment: accepted version

The movement of small particles and molecules through membranes is widespread and has far-reaching implications. Consequently, the development of mathematical models is essential for understanding these processes on a micro level, leading to deeper insights. In this endeavour, we suggested a model based on a set of empirical equations to predict the transport of substances through a solid-state nanopore and the associated signals generated during their translocation. This model establishes analytical relationships between the ionic current and electrical double-layer potential observed during ana-lyte translocation and their size, charge, and mobility in an electrolyte solution. This framework allows for rapid interpretation and prediction of the nanopore system's behaviour and provides a means for quantitatively determining the physical properties of molecular analytes. To illustrate the analyt-ical capability of this model, ceria nanoparticles were investigated while undergoing oxidation or reduction within an original nanopore device. The re-sults obtained were found to be in good agreement with predictions from physicochemical methods. This developed approach and model possess transfer-able utility to various porous materials, thereby expediting research efforts in membrane characterization and the advancement of nano- and ultrafiltra-tion or electrodialysis technologies.

We introduce the notion of paraquaternionic contact structures (pqc structures), which turns out to be a generalization of the para 3-Sasakian geometry. We derive a distinguished linear connection preserving the pqc structure. Its torsion tensor is expressed explicitly in terms of the structure tensors and the structure equations of a pqc manifold are presented. We define pqc-Einstein manifolds and show that para 3-Sasakian spaces are precisely pqc manifolds, which are pqc-Einstein. Furthermore, we introduce the paraquaternionic Heisenberg qroup and show that it is the flat model of the pqc geometry., Comment: 28 pages, no figures, typos corrected

A tensor invariant is defined on a paraquaternionic contact manifold in terms of the curvature and torsion of the canonical paraquaternionic connection involving derivatives up to third order of the contact form. This tensor, called paraquaternionic contact conformal curvature, is similar to the Weyl conformal curvature in Riemannian geometry, the Chern-Moser tensor in CR geometry, the para contact curvature in para CR geometry and to the quaternionic contact conformal curvature in quaternionic contact geometry. It is shown that a paraquaternionic contact manifold is locally paraquaternionic contact conformal to the standard flat paraquaternionic contact structure on the paraquaternionic Heisenberg group, or equivalently, to the standard para 3-Sasakian structure on the paraquaternionic pseudo-sphere iff the paraquaternionic contact conformal curvature vanishes., Comment: 29 pages, no figures, misprints and typos corrected. arXiv admin note: substantial text overlap with arXiv:0707.1289

We suggest new modification (we call it a noise reduction procedure) for Steinhardt parameters which are often used for detecting crystalline structures in computer simulation of solids and soft matter systems. We have also developed a new methodology how to reconstruct "ideal" lattice structure in the whole simulation box that would be most close to a real noisy crystalline symmetry, when it is defined locally and then averaged over the whole box. For this second procedure, which we call lattice reconstruction procedure, we have developed an algorithm for finding the lattice vectors from the values of Steinhardt parameters obtained after the noise reduction procedure. We apply noise to the classical crystalline structures (sc, bcc, fcc, hcp), and use both procedures to detect the crystalline structures in these classical but noisy systems. We demonstrate advantages of our procedures in comparison with existing methods and discuss their applicability limits.

We study the rare semileptonic decays of $B_c$ mesons within the effective field theoretical framework of covariant confined quark model. The transition form factors corresponding to $B_c^+ \to D^{(*)+}$ and $B_c^+ \to D_s^{(*)+}$ are computed in the entire $q^2$ range. Using form factors, we compute the branching fractions and compare them with the available theoretical results. We also compute various physical observables such as forward-backward asymmetry, longitudinal and transverse polarizations as well as clean angular observables.

We consider linear search for an escaping target whose speed and initial position are unknown to the searcher. A searcher (an autonomous mobile agent) is initially placed at the origin of the real line and can move with maximum speed $1$ in either direction along the line. An oblivious mobile target that is moving away from the origin with an unknown constant speed $v<1$ is initially placed by an adversary on the infinite line at distance $d$ from the origin in an unknown direction. We consider two cases, depending on whether $d$ is known or unknown. The main contribution of this paper is to prove a new lower bound and give algorithms leading to new upper bounds for search in these settings. This results in an optimal (up to lower order terms in the exponent) competitive ratio in the case where $d$ is known and improved upper and lower bounds for the case where $d$ is unknown. Our results solve an open problem proposed in [Coleman et al., Proc. OPODIS 2022].

We present the results and the main findings of SemEval-2024 Task 8: Multigenerator, Multidomain, and Multilingual Machine-Generated Text Detection. The task featured three subtasks. Subtask A is a binary classification task determining whether a text is written by a human or generated by a machine. This subtask has two tracks: a monolingual track focused solely on English texts and a multilingual track. Subtask B is to detect the exact source of a text, discerning whether it is written by a human or generated by a specific LLM. Subtask C aims to identify the changing point within a text, at which the authorship transitions from human to machine. The task attracted a large number of participants: subtask A monolingual (126), subtask A multilingual (59), subtask B (70), and subtask C (30). In this paper, we present the task, analyze the results, and discuss the system submissions and the methods they used. For all subtasks, the best systems used LLMs., Comment: 23 pages, 12 tables

We present the first constraints on tidal heating for the binary systems detected in the LIGO-Virgo-KAGRA (LVK) gravitational wave data. Tidal heating, also known as tidal dissipation, characterizes the viscous nature of an astrophysical body and provides a channel for exchanging energy and angular momentum with the tidal environment. Using the worldline effective field theory formalism, we introduce a physically motivated and easily interpretable parametrization of tidal heating valid for an arbitrary compact astrophysical object. We then derive the imprints of the spin-independent and linear-in-spin tidal heating effects of generic binary components on the waveform phases and amplitudes of quasi-circular orbits. Notably, the mass-weighted spin-independent tidal heating coefficient derived in this work, $\mathcal{H}_0$, is the dissipative analog of the tidal Love number. We constrain the tidal heating coefficients using the public LVK O1-O3 data. Our parameter estimation study includes two separate analyses: the first treats the catalog of binary events as binary black holes (BBH), while the second makes no assumption about the nature of the binary constituents and can therefore be interpreted as constraints for exotic compact objects. In the former case, we combine the posterior distributions of the individual BBH events and obtain a joint constraint of $-13 < \mathcal{H}_0 < 20$ at the $90\%$ credible interval for the BBH population. This translates into a bound on the fraction of the emitted gravitational wave energy lost due to tidal heating (or gained due to radiation enhancement effects) at $|\Delta E_H/\Delta E_{\infty}|\lesssim 3\cdot 10^{-3}$. Our work provides the first robust framework for deriving and measuring tidal heating effects in merging binary systems, demonstrating its potential as a powerful probe of the nature of binary constituents and tests of new physics., Comment: 30+18 pages, 7 figures

We continue classification of finite groups which can be used as symmetry group of the scalar sector of the four-Higgs-doublet model (4HDM). Our objective is to systematically construct non-abelian groups via the group extension procedure, starting from the abelian groups $A$ and their automorphism groups $\mathrm{Aut}(A)$. Previously, we considered all cyclic groups $A$ available for the 4HDM scalar sector. Here, we further develop the method and apply it to extensions by the remaining rephasing groups $A$, namely $A = \mathbb{Z_2}\times\mathbb{Z_2}$, $\mathbb{Z_4}\times \mathbb{Z_2}$, and $\mathbb{Z_2}\times \mathbb{Z_2}\times \mathbb{Z_2}$. As $\mathrm{Aut}(A)$ grows, the procedure becomes more laborious, but we prove an isomorphism theorem which helps classify all the options. We also comment on what remains to be done to complete the classification of all finite non-abelian groups realizable in the 4HDM scalar sector without accidental continuous symmetries., Comment: 27 pages, 0 figures, 4 tables. v2: extra clarifications, matches the published version

One of the ways to make artificial intelligence more natural is to give it some room for doubt. Two main questions should be resolved in that way. First, how to train a model to estimate uncertainties of its own predictions? And then, what to do with the uncertain predictions if they appear? First, we proposed an uncertainty-aware negative log-likelihood loss for the case of N-dimensional multivariate normal distribution with spherical variance matrix to the solution of N-classes classification tasks. The loss is similar to the heteroscedastic regression loss. The proposed model regularizes uncertain predictions, and trains to calculate both the predictions and their uncertainty estimations. The model fits well with the label smoothing technique. Second, we expanded the limits of data augmentation at the training and test stages, and made the trained model to give multiple predictions for a given number of augmented versions of each test sample. Given the multi-view predictions together with their uncertainties and confidences, we proposed several methods to calculate final predictions, including mode values and bin counts with soft and hard weights. For the latter method, we formalized the model tuning task in the form of multimodal optimization with non-differentiable criteria of maximum accuracy, and applied particle swarm optimization to solve the tuning task. The proposed methodology was tested using CIFAR-10 dataset with clean and noisy labels and demonstrated good results in comparison with other uncertainty estimation methods related to sample selection, co-teaching, and label smoothing.

This study introduces a Kalman Filter tailored for homogeneous gas Time Projection Chambers (TPCs), adapted from the algorithm utilized by the ALICE experiment. In order to describe semi-circular paths in the plane perpendicular to the magnetic field, we introduce a novel mirror rotation technique into the Kalman Filter algorithm, enabling effective tracking of trajectories of varying lengths, including those with multiple circular paths within the detector, also known as "loopers". Demonstrated relative improvements of up to 80% in electron momentum resolution and up to 50% in muon and pion momentum resolution underscore the significance of this enhancement. Significant improvements in the reconstruction efficiency for relatively short low momentum "looper" tracks are also shown. Such advancements hold promise not only for the future of the ALICE TPC but also for neutrino high-pressure gas TPCs, where loopers become significant owing to the randomness of production points and their relatively low energies in neutrino interactions. In particular, an improvement in low energy electron reconstruction, for which the production of "looping" tracks is likely and the impact of the new algorithm is directly demonstrated, could significantly impact the quality of flux determination, which in accelerator neutrino experiments relies on the measurement of $\nu_e$ electron scatterings., Comment: 44 pages, 25 figures

The paper studies the quantum action for the five-dimensional real $\phi^3$-theory in the case of a general formulation using the background field method. The three-loop renormalization is performed with the usage of a cutoff regularization in the coordinate representation. The explicit form of the first three coefficients for the renormalization constants is presented. The absence of non-local singular contributions and partial results for the fourth correction are discussed., Comment: LaTeX, 20 pages, 5 figures. Firstly appeared in Russian, April 9, 2024, see https://www.pdmi.ras.ru/preprint/2024/24-05.html

EX Lupi, a low-mass young stellar object, went into an accretion-driven outburst in March of 2022. The outburst caused a sudden phase change of ~ 112$^{\circ}$ $\pm$ 5$^{\circ}$ in periodically oscillating multiband lightcurves. Our high resolution spectra obtained with HRS on SALT also revealed a consistent phase change in the periodically varying radial velocities, along with an increase in the radial velocity amplitude of various emission lines. The phase change and increase of radial velocity amplitude morphologically translates to a change in the azimuthal and latitudinal location of the accretion hotspot over the stellar surface, which indicates a reconfiguration of the accretion funnel geometry. Our 3D MHD simulations reproduce the phase change for EX Lupi. To explain the observations we explored the possibility of forward shifting of the dipolar accretion funnel as well as the possibility of an emergence of a new accretion funnel. During the outburst, we also found evidence of the hotspot's morphology extending azimuthally, asymmetrically with a leading hot edge and cold tail along the stellar rotation. Our high cadence photometry showed that the accretion flow has clumps. We also detected possible clumpy accretion events in the HRS spectra, that showed episodically highly blue-shifted wings in the Ca II IRT and Balmer H lines., Comment: Accepted for publication in The Astrophysical Journal

In this paper, we propose a new approach to justify a round-off error impact on the accuracy of the linear least squares (LS) solution using Cholesky decomposition. This decomposition is widely employed to inverse a matrix in the linear detector of the Multi-User multi-antenna receiver. The proposed stochastic bound is much closer to actual errors than other numerical bounds. It was tested with a half-precision format and validated in realistic scenarios. Experimental results demonstrate our approach predicts errors very close to those achieved by simulations. The proposed approach can be employed to analyze the resulting round-off error in many other applications.

Understanding spin and lattice excitations in a metallic magnetic ordered system form the basis to unveil the magnetic and lattice exchange couplings and their interactions with itinerant electrons. Kagome lattice antiferromagnet FeGe is interesting because it displays rare charge density wave (CDW) deep inside the antiferromagnetic ordered phase that interacts with the magnetic order. We use neutron scattering to study the evolution of spin and lattice excitations across the CDW transition $T_{\rm CDW}$ in FeGe. While spin excitations below $\sim$100 meV can be well described by spin waves of a spin-1 Heisenberg Hamiltonian, spin excitations at higher energies are centered around the Brillouin zone boundary and extend up to $\sim180$ meV consistent with quasiparticle excitations across spin-polarized electron-hole Fermi surfaces. Furthermore, $c$-axis spin wave dispersion and Fe-Ge optical phonon modes show a clear hardening below $T_{\rm CDW}$ due to spin-charge-lattice coupling but with no evidence for a phonon Kohn anomaly. By comparing our experimental results with density functional theory calculations in absolute units, we conclude that FeGe is a Hund's metal in the intermediate correlated regime where magnetism has contributions from both itinerant and localized electrons arising from spin polarized electronic bands near the Fermi level.

Superconducting domes, ubiquitous across a variety of quantum materials, are often understood as a window favorite for pairing opened by the fluctuations of competing orders. Yet, a quantitative understanding of how such a window closes is missing. Here, we show that inelastic neutron scattering, by quantifying a length scale associated with polar fluctuations, $\ell_0$, addresses this issue. We find that the superconducting dome of strontium titanate definitely ends when $\ell_0$ vanishes. Moreover, the product of $\ell_0$ and the Fermi wavevector peaks close to the maximum critical temperature. Thus, this superconducting dome stems from the competition between the increase of the density of states and the unavoidable collapse of the quantum paraelectric phase, both induced by doping. The successful quantitative account of both the peak and the end of the superconducting dome implies a central role in the pairing mechanism played by the soft ferro-electric mode and its hybridisation with the acoustic branch. Such a scenario may also be at work in other quantum paraelectric materials, either bulk or interfaces., Comment: SM on request

We propose a novel architecture and method of explainable classification with Concept Bottleneck Models (CBMs). While SOTA approaches to Image Classification task work as a black box, there is a growing demand for models that would provide interpreted results. Such a models often learn to predict the distribution over class labels using additional description of this target instances, called concepts. However, existing Bottleneck methods have a number of limitations: their accuracy is lower than that of a standard model and CBMs require an additional set of concepts to leverage. We provide a framework for creating Concept Bottleneck Model from pre-trained multi-modal encoder and new CLIP-like architectures. By introducing a new type of layers known as Concept Bottleneck Layers, we outline three methods for training them: with $\ell_1$-loss, contrastive loss and loss function based on Gumbel-Softmax distribution (Sparse-CBM), while final FC layer is still trained with Cross-Entropy. We show a significant increase in accuracy using sparse hidden layers in CLIP-based bottleneck models. Which means that sparse representation of concepts activation vector is meaningful in Concept Bottleneck Models. Moreover, with our Concept Matrix Search algorithm we can improve CLIP predictions on complex datasets without any additional training or fine-tuning. The code is available at: https://github.com/Andron00e/SparseCBM., Comment: 23 pages, 1 algorithm, 36 figures

Massive particles leave imprints on primordial non-Gaussianity via couplings to the inflaton, even despite their exponential dilution during inflation: practically, the Universe acts as a Cosmological Collider. We present the first dedicated search for spin-zero particles using BOSS redshift-space galaxy power spectrum and bispectrum multipoles, as well as Planck CMB non-Gaussianity data. We demonstrate that some Cosmological Collider models are well approximated by the standard equilateral and orthogonal parametrization; assuming negligible inflaton self-interactions, this facilitates us translating Planck non-Gaussianity constraints into bounds on Collider models. Many models have signatures that are not degenerate with equilateral and orthogonal non-Gaussianity and thus require dedicated searches. Here, we constrain such models using BOSS three-dimensional redshift-space galaxy clustering data, focusing on spin-zero particles in the principal series and constraining their couplings to the inflaton at varying speed and mass, marginalizing over the unknown inflaton self-interactions. This is made possible through an improvement in Cosmological Bootstrap techniques and the combination of perturbation theory and halo occupation distribution models for galaxy clustering. Our work sets the standard for inflationary spectroscopy with cosmological observations, providing the ultimate link between physics on the largest and smallest scales., Comment: 35 pages, 15 figures, 6 tables

CP4 3HDM is a three-Higgs-doublet model based on a $CP$ symmetry of order 4 (CP4). It is the minimal model incorporating CP4 without leading to accidental symmetries or running into immediate conflict with experiment. Imposing CP4 on the lagrangian induces remarkably tight connections between the scalar and Yukawa sectors, including the unavoidable tree-level flavor-changing neutral couplings (FCNC). Here, we explore whether it is at all possible in the CP4 3HDM to suppressed FCNC to a level compatible with the neutral meson oscillation constraints. We express the FCNC matrices in terms of physical quark observables and quark rotation parameters, and scan the Yukawa parameter space using the quark masses and mixing parameters as input. With this procedure, we find that only two out of the eight possible CP4 Yukawa sectors are compatible with the $K$, $B$, $B_s$ and, in particular, $D$-meson oscillation constraints. The results clearly indicate a way how to construct phenomenologically viable benchmark CP4 3HDMs., Comment: 14 pages, 3 figures, Proceedings of the "Workshop on the Standard Model and Beyond" within the Corfu Summer Institute 2023, Corfu, Greece, August 27 - September 7, 2023

We propose a novel method for changing the length of laser wakefield electron acceleration in a gas jet by a cylindrical blast wave created by a perpendicularly focused nanosecond laser pulse. The shock front destroys the wake thus stopping interaction between the laser pulse and accelerated electron bunch allowing one to directly control the interaction length and avoid dephasing. It also improves the electron beam quality through the plasma lensing effect between the two shock fronts. We demonstrated both experimentally and numerically how this approach can be used to form quasi-monoenergetic electron bunch with controlled energy and improved divergence as well as to track changes in the bunch parameters during acceleration.

We show that fast technical fluctuations of microwave signals can be strongly suppressed by cryogenic resonators. The experiments were carried out with sapphire resonators cooled to approximately 6 K at frequencies around 11 GHz. Each sapphire crystal was shaped like a spindle with the rotational and crystal axes aligned within a degree. Noise suppression factors in excess of 50 dB were measured at 10 kHz offset from the carrier. This was achieved by rotating the sapphire spindle and moving the coupling probes relative to its surface. Microwave signals with reduced fast technical fluctuations allow the high-precision tests of fundamental physics, as well as the development of better radars., Comment: 4 pages, 7 figures

We show that state-of-the-art phase noise and high frequency stability could be simultaneously achieved in a microwave oscillator based on the sapphire-loaded cavity resonator. The 9 GHz sapphire oscillator was constructed with the SSB phase noise close to -170 dBc/Hz at an offset frequency of 10 kHz and fractional frequency instability less than 2 10$^{-13}$ for integration times from 5 to 50 s. In this work, we focus on the technique for phase-referencing the microwave sapphire oscillator to a stable radio-frequency source. We also discuss the suppression of the fast phase fluctuations of the microwave signal due to its transmission through the high-Q resonator., Comment: 4 pages, 9 figures

We investigate the elastic behavior of two-dimensional crystalline membrane embedded into real space taking into account the presence an arbitrary number of flexural phonon modes $d_c$ (the number of out-of-plane deformation field components). The bending rigidity exponent $\eta$ is extracted by numerical simulation via Fourier Monte Carlo technique of the system behaviour in the universal regime. This universal quantity governess the correlation function of out-of-plane deformations at long wavelengths and defines the behaviour of renormalized bending rigidity at small momentum $\varkappa~\sim~1/q^{\eta}$. The resulting numerical estimates of the exponent for various $d_c$ are compared with the numbers obtained from the approximate analytical techniques.

One can infer the orbital alignment of exoplanets with respect to the spin of their host stars using the Rossiter-McLaughlin effect, thereby giving us the chance to test planet formation and migration theories and improve our understanding of the currently observed population. We analyze archival HARPS and HARPS-N spectroscopic transit time series of six gas giant exoplanets on short orbits, namely WASP-77 Ab, WASP-101b, WASP-103b, WASP-105b, WASP-120b and WASP-131b. We find a moderately misaligned orbit for WASP-101b ($\lambda =34\degree\ \pm$ 3) and a highly misaligned orbit for WASP-131b ($\lambda =161\degree\ \pm$ 5), while the four remaining ones appear aligned: WASP-77 Ab ($\lambda =-8\degree\ ^{+19}_{-18}$), WASP-103b ($\lambda =2\degree\ ^{+35}_{-36}$), WASP-105b ($\lambda =-14\degree\ ^{+28}_{-24}$), and WASP-120b ($\lambda =-2\degree\ \pm$ 4). For WASP-77 Ab, we were able to infer its true orbital obliquity ($\Psi =48\degree\ ^{+22}_{-21}$). We additionally perform transmission spectroscopy of the targets in search of strong atomic absorbers in the exoatmospheres, but are unable to detect any features, most likely due to the presence of high-altitude clouds or Rayleigh scattering muting the strength of the features. Finally, we comment on future perspectives for studying these targets with the upcoming space missions to investigate the evolution and migration histories of these planets., Comment: Accepted to A&A

The classical Steinitz theorem asserts that if the origin lies within the interior of the convex hull of a set $S \subset \mathbb{R}^d$, then there are at most $2d$ points in $S$ whose convex hull contains the origin within its interior. B\'ar\'any, Katchalski, and Pach established a quantitative version of Steinitz's theorem, showing that for a convex polytope $Q$ in $\mathbb{R}^d$ containing the standard Euclidean unit ball $\mathbf{B}^d$, there exist at most $2d$ vertices of $Q$ whose convex hull $Q'$ satisfies $r\mathbf{B}^d \subset Q' $ with $r \geq d^{-2d}$. Recently, M\'arton Nasz\'odi and the author derived a polynomial bound on $r$. This paper aims to establish a bound on $r$ based on the number of vertices of $Q.$ In other words, we demonstrate an effective method to remove several points from the original set $Q$ without significantly altering the bound on $r$. Specifically, if the number of vertices of $Q$ scales linearly with the dimension, i.e., $cd$, then one can select $2d$ vertices such that $r \geq \frac{1}{5cd}$. The proof relies on a polarity trick, which may be of independent interest: we demonstrate the existence of a point $p$ in the interior of a convex polytope $P \subset \mathbb{R}^d$ such that the vertices of the polar polytope $(P-p)^\circ$ sum up to zero.

Antiferromagnets (AFMs) have great benefits for spintronic applications such as high frequencies (up to THz), high speeds (up to tens of km/s) of magnetic excitations, and field-free operation. Advanced devices will require high-speed propagating spin waves (SWs) as signal carriers, i.e., SWs with high k-vectors, the excitation of which remains challenging. We show that a domain wall (DW) in anisotropic AFM driven by the spin current can be a source of such propagating SWs with high frequencies and group velocities. In the proposed generator, the spin current, with polarization directed along the easy anisotropy axis, excites the precession of the N\'eel vector within the DW. The threshold current is defined by the value of the anisotropy in the hard plane, and the frequency of the DW precession is tuneable by the strength of the spin current. We show that the above precession of spins inside the DW leads to robust emission of high-frequency propagating SWs into the AFM strip with very short wavelengths comparable to the exchange length, which is hard to achieve by any other method., Comment: 6 pages, 4 figures; supplementary material 4 pages

Measuring the energy loss and mass of highly ionizing particles predicted by theories from beyond the Standard Model pose considerable challenges to conventional detection techniques. Such particles are predicted to experience energy loss to matter they pass through that exceeds the dynamic range specified for most readout chips, leading to saturation of the detectors' electronics. Consequently, achieving precise energy loss and mass measurements becomes unattainable. We present a new approach to detect such highly ionizing particles using time projection chambers that overcomes this limitation and provide a case study for triggering on magnetic monopoles., Comment: 9 pages, 5 figures

Finding methods for the most efficient and fastest detection and control of magnetic domains in antiferromagnets is presently among the main challenges of magnetic research at large. We analyse the problem of optical read-out and control of the antiferromagnetic Neel vector using symmetry analysis and the principles of equilibrium thermodynamics. Following the pioneering approach of Dzyaloshinksii, we divide all antiferromagnets in three classes. It is shown that, using the magneto-optical Faraday effect or other effects which scale linearly with the antiferromagnetic Neel vector, it is possible to distinguish antiferromagnetic domains with mutually opposite N\'eel vectors in two of the three classes. Symmetry properties of one of these two classes are similar to those of altermagnets. The analysis also reveals multiple mechanisms to directly excite spins with light for practically every type of antiferromagnet.

The paper discusses an applicability criterion for a cutoff regularization in the coordinate representation in the Euclidean space with a dimension larger than two. It is shown that the set of functions satisfying the criterion is not empty. As an example, an explicit function is presented. It is proved by explicit construction that there are functions satisfying the criterion in a stronger formulation., Comment: LaTeX, 8 pages, 1 figure. Firstly appeared in Russian, March 5, 2024. Compared to the Russian version, some comments and minor corrections have been added. The forgotten imaginary unit in the Fourier transform has also been restored. See https://www.pdmi.ras.ru/preprint/2024/24-04.html

In this work, we report first exact volume-entangled Einstein-Podolsky-Rosen (EPR) type scar states hosted by PXP and related Hamiltonians corresponding to various geometric configurations of Rydberg-blockaded atom systems, including the most extensively studied ones such as the chain with periodic boundary conditions (PBC) and square lattice. We start by introducing a new zero-energy eigenstate of the PBC chain and proceed by generalizing it to a wide variety of geometries and Hamiltonians. We point out the experimental relevance of such states by providing a concrete and feasible protocol for their preparation on near-term Rydberg quantum devices, which relies only on strictly local measurements and evolution under native Hamiltonians. We also demonstrate the utility of these states for the study of quantum dynamics by describing a simple protocol for measuring infinite-temperature out-of-time-order correlator (OTOC) functions., Comment: 5+14 pages, 3+6 figures

The Wide-field Spectroscopic Telescope (WST) is proposed as a new facility dedicated to the efficient delivery of spectroscopic surveys. This white paper summarises the initial concept as well as the corresponding science cases. WST will feature simultaneous operation of a large field-of-view (3 sq. degree), a high multiplex (20,000) multi-object spectrograph (MOS) and a giant 3x3 sq. arcmin integral field spectrograph (IFS). In scientific capability these requirements place WST far ahead of existing and planned facilities. Given the current investment in deep imaging surveys and noting the diagnostic power of spectroscopy, WST will fill a crucial gap in astronomical capability and work synergistically with future ground and space-based facilities. This white paper shows that WST can address outstanding scientific questions in the areas of cosmology; galaxy assembly, evolution, and enrichment, including our own Milky Way; origin of stars and planets; time domain and multi-messenger astrophysics. WST's uniquely rich dataset will deliver unforeseen discoveries in many of these areas. The WST Science Team (already including more than 500 scientists worldwide) is open to the all astronomical community. To register in the WST Science Team please visit https://www.wstelescope.com/for-scientists/participate, Comment: 194 pages, 66 figures. Comments are welcome (wstelescope@gmail.com)

One common way to speed up the find operation within a set of text files involves a trigram index. This structure is merely a map from a trigram (sequence consisting of three characters) to a set of files which contain it. When searching for a pattern, potential file locations are identified by intersecting the sets related to the trigrams in the pattern. Then, the search proceeds only in these files. However, in a code repository, the trigram index evolves across different versions. Upon checking out a new version, this index is typically built from scratch, which is a time-consuming task, while we want our index to have almost zero-time startup. Thus, we explore the persistent version of a trigram index for full-text and key word patterns search. Our approach just uses the current version of the trigram index and applies only the changes between versions during checkout, significantly enhancing performance. Furthermore, we extend our data structure to accommodate CamelHump search for class and function names.