ShantanuT01/DACTYL-Pretraining huggingface dataset:
We study the effects of collective neutrino oscillations on $\nu p$ process nucleosynthesis in proton-rich neutrino-driven winds by including both the multi-angle $3\times3$ flavor mixing and the nucleosynthesis network calculation. The number flux of energetic electron antineutrinos is raised by collective neutrino oscillations in a $1$D supernova model for $40 M_{\odot}$ progenitor. When the gas temperature decreases down to $\sim2-3\times10^{9}$ K, the increased flux of electron antineutrinos promotes $\nu p$ process more actively, resulting in the enhancement of $p$-nuclei. In the early phase of neutrino-driven wind, blowing at $0.6$ s after core bounce, oscillation effects are prominent in inverted mass hierarchy and $p$-nuclei are synthesized up to $^{106}\mathrm{Cd}$ and $^{108}\mathrm{Cd}$. On the other hand, in the later wind trajectory at $1.1$ s after core bounce, abundances of $p$-nuclei are increased remarkably by $\sim10-10^{4}$ times in normal mass hierarchy and even reaching heavier $p$-nuclei such as $^{124}\mathrm{Xe}$, $^{126}\mathrm{Xe}$ and $^{130}\mathrm{Ba}$. The averaged overproduction factor of $p$-nuclei is dominated by the later wind trajectories. Our results demonstrate that collective neutrino oscillations can strongly influence $\nu p$ process, which indicates that they should be included in the network calculations in order to obtain precise abundances of $p$-nuclei. The conclusions of this paper depend on the difference of initial neutrino parameters between electron and non-electron antineutrino flavors which is large in our case. Further systematic studies on input neutrino physics and wind trajectories are necessary to draw a robust conclusion. However, this finding would help understand the origin of solar-system isotopic abundances of $p$-nuclei such as $^{92,94}\mathrm{Mo}$ and $^{96,98}\mathrm{Ru}$.
Given a category fibered in groupoids over schemes with a log structure, one produces a category fibered in groupoids over log schemes. We classify the groupoid fibrations over log schemes that arise in this manner in terms of a categorical notion of "minimal" objects. The classification is actually a purely category-theoretic result about groupoid fibrations over fibered categories, though most of the known applications occur in the setting of log geometry, where our categorical framework encompasses many notions of "minimality" previously extant in the literature.
We present several new algorithms for computing factorization invariant values over affine semigroups. In particular, we give (i) the first known algorithm to compute the delta set of any affine semigroup, (ii) an improved method of computing the tame degree of an affine semigroup, and (iii) a dynamic algorithm to compute catenary degrees of affine semigroup elements. Our algorithms rely on theoretical results from combinatorial commutative algebra involving Gr\"obner bases, Hilbert bases, and other standard techniques. Implementation in the computer algebra system GAP is discussed.
The Serpens filament, as one of the nearest infrared dark clouds, is regarded as a pristine filament at a very early evolutionary stage of star formation. In order to study its molecular content and dynamical state, we mapped this filament in seven species. Among them, HCO$^{+}$, HNC, HCN, and CS show self-absorption, while C$^{18}$O is most sensitive to the filamentary structure. A kinematic analysis demonstrates that this filament forms a velocity-coherent (trans-)sonic structure, a large part of which is one of the most quiescent regions in the Serpens cloud. Widespread C$^{18}$O depletion is found throughout the Serpens filament. Based on the Herschel dust-derived H$_{2}$ column density map, the line mass of the filament is 36--41~M$_{\odot}$~pc$^{-1}$, and its full width at half maximum is 0.17$\pm$0.01~pc, while its length is ~1.6~pc. The inner radial column density profile of this filament can be well fitted with a Plummer profile with an exponent of 2.2$\pm$0.1, a scale radius of $0.018\pm 0.003$ pc, and a central density of $(4.0\pm 0.8)\times 10^{4}$~cm$^{-3}$. The Serpens filament appears to be slightly supercritical. The widespread blue-skewed HNC and CS line profiles and HCN hyperfine line anomalies across this filament indicate radial infall in parts of the Serpens filament. C$^{18}$O velocity gradients also indicate accretion flows along the filament. The velocity and density structures suggest that such accretion flows are likely due to a longitudinal collapse parallel to the filament's long axis. Both the radial infall rate and the longitudinal accretion rate along the Serpens filament are lower than all previously reported values in other filaments. This indicates that the Serpens filament lies at an early evolutionary stage when collapse has just begun, or that thermal and non-thermal support are effective in providing support against gravity.
We give necessary and sufficient conditions for existence and infinite divisibility of $\alpha$-determinantal processes. For that purpose we use results on negative binomial and ordinary binomial multivariate distributions.
The multi-TeV $\gamma$-rays from the Galactic Center (GC) have a cutoff at tens of TeV, whereas the diffuse emission has no such cutoff, which is regarded as an indication of PeV proton acceleration by the HESS experiment. It is important to understand the inconsistency and study the possibility that PeV cosmic-ray acceleration could account for the apparently contradictory point and diffuse $\gamma$-ray spectra. In this work, we propose that the cosmic rays are accelerated up to $>$PeV in GC. The interaction between cosmic rays and molecular clouds is responsible for the multi-TeV $\gamma$-ray emissions from both the point source and diffuse sources today. Enhanced by the small volume filling factor (VFF) of the clumpy structure, the absorption of the $\gamma$-rays leads to a sharp cutoff spectrum at tens of TeV produced in the GC. Away from galactic center, the VFF grows and the absorption enhancement becomes negligible. As a result, the spectra of $\gamma$-ray emissions for both point source and diffuse sources can be successfully reproduced under such self-consistent picture. In addition, a "surviving-tail" at $\sim$100 TeV is expected from the point source, which can be observed by future projects CTA and LHAASO. Neutrinos are simultaneously produced during proton-proton (PP) collision. With 5-10 years observations, the KM3Net experiment will be able to detect the PeV source according to our calculation.
I describe a new Markov chain method for sampling from the distribution of the state sequences in a non-linear state space model, given the observation sequence. This method updates all states in the sequence simultaneously using an embedded Hidden Markov model (HMM). An update begins with the creation of a ``pool'' of K states at each time, by applying some Markov chain update to the current state. These pools define an embedded HMM whose states are indexes within this pool. Using the forward-backward dynamic programming algorithm, we can then efficiently choose a state sequence at random with the appropriate probabilities from the exponentially large number of state sequences that pass through states in these pools. I show empirically that when states at nearby times are strongly dependent, embedded HMM sampling can perform better than Metropolis methods that update one state at a time.
We derive exact, modified geodesic equations for a system of non-spinning, self-gravitating interacting bodies in a class of alternative theories of gravity to general relativity. We use a prescription proposed by Eardley for incorporating the effects of self-gravity within gravitationally bound bodies, in which their masses may depend on invariant quantities constructed from the auxiliary scalar, vector or tensor fields introduced by such theories, evaluated in the vicinity of each body. The forms of the equations are independent of the field equations of the chosen theory. In the case where the masses are strictly constant, the equations reduce to the conventional geodesic equations of general relativity. These equations may be useful tools for deriving equations of motion for compact bodies to high post-Newtonian orders in alternative theories of gravity.
Fossil groups are expected to be the final product of galaxy merging within galaxy groups. In simulations, they are predicted to assemble their mass at high redshift. This early formation allows for the innermost $M^\ast$ galaxies to merge into a massive central galaxy. Then, they are expected to maintain their fossil status because of the few interactions with the large-scale structure. In this context, the magnitude gap between the two brightest galaxies of the system is considered a good indicator of its dynamical status. As a consequence, the systems with the largest gaps should be dynamically relaxed. In order to examine the dynamical status of these systems, we systematically analyze, for the first time, the presence of galaxy substructures in a sample of 12 spectroscopically-confirmed fossil systems with redshift $z \le 0.25$. We apply a number of tests in order to investigate the substructure in fossil systems in the two-dimensional space of projected positions out to $R_{200}$. Moreover, for a subsample of 5 systems with at least 30 spectroscopically-confirmed members we also analyze the substructure in the velocity and in the three-dimensional velocity-position spaces. Additionally, we look for signs of recent mergers in the regions around the central galaxies. We find that an important fraction of fossil systems show substructure. The fraction depends critically on the adopted test, since each test is more sensible to a particular type of substructure. Our interpretation of the results is that fossil systems are not, in general, as relaxed as expected from simulations. Our sample of 12 spectroscopically-confirmed fossil systems need to be extended in order to compute an accurate fraction, but our conclusion is that it is similar to the fraction of substructure detected in non-fossil clusters. THIS ABSTRACT IS TRUNCATED.
The precise and accurate segmentation of the vertebral column is essential in the diagnosis and treatment of various orthopedic, neurological, and oncological traumas and pathologies. Segmentation is especially challenging in the presence of pathology such as vertebral compression fractures. In this paper, we propose a method to produce segmentations for osteoporotic compression fractured vertebrae by applying a multi-atlas joint label fusion technique for clinical CT images. A total of 170 thoracic and lumbar vertebrae were evaluated using atlases from five patients with varying degrees of spinal degeneration. In an osteoporotic cohort of bundled atlases, registration provided an average Dice coefficient and mean absolute surface distance of 2.7$\pm$4.5% and 0.32$\pm$0.13mm for osteoporotic vertebrae, respectively, and 90.9$\pm$3.0% and 0.36$\pm$0.11mm for compression fractured vertebrae.
The influence of a transverse static magnetic field on the magnetic hyperthermia properties is studied on a system of large-losses ferromagnetic FeCo nanoparticles. The simultaneous measurement of the high-frequency hysteresis loops and of the temperature rise provides an interesting insight into the losses and heating mechanisms. A static magnetic field of only 40 mT is enough to cancel the heating properties of the nanoparticles, a result reproduced using numerical simulations of hysteresis loops. These results cast doubt on the possibility to perform someday magnetic hyperthermia inside a magnetic resonance imaging setup.
Using one-dimensional spin-1/2 systems as prototypes of quantum many-body systems, we study the emergence of quantum chaos. The main purpose of this work is to answer the following question: how does the spin-orbit interaction, as a pure quantum interaction, may lead to the onset of quantum chaos? We consider three integrable spin-1/2 systems: the Ising, the XX, and the XXZ limits, and analyze whether quantum chaos develops or not after the addition of the Dzyaloshinskii-Moriya interaction. We find that, depending on the strength of the anisotropy parameter, the answer is positive for the XXZ and Ising models, while no such evidence is observed for the XX model. We also discuss the relationship between quantum chaos and thermalization.
It is well known that measurements of H0 from gravitational lens time delays scale as H0~1-k_E where k_E is the mean convergence at the Einstein radius R_E but that all available lens data other than the delays provide no direct constraints on k_E. The properties of the radial mass distribution constrained by lens data are R_E and the dimensionless quantity x=R_E a''(R_E)/(1-k_E)$ where a''(R_E) is the second derivative of the deflection profile at R_E. Lens models with too few degrees of freedom, like power law models with densities ~r^(-n), have a one-to-one correspondence between x and k_E (for a power law model, x=2(n-2) and k_E=(3-n)/2=(2-x)/4). This means that highly constrained lens models with few parameters quickly lead to very precise but inaccurate estimates of k_E and hence H0. Based on experiments with a broad range of plausible dark matter halo models, it is unlikely that any current estimates of H0 from gravitational lens time delays are more accurate than ~10%, regardless of the reported precision.
This work reports the first discovery of (negative) spectral lags in the X-ray emission below 10 keV from the gamma ray binary $LSI +61^{o} $ 303 during large flaring episodes using the Rossi X-ray Timing Explorer (RXTE) observations. It is found from the RXTE data that during the flares, low energy (3-5 KeV) variations lead the higher energy (8-10 keV) variations by few tens of seconds whereas no significant time lag is observed during the non-flaring states. The observed spectral lag features for flaring events suggest that inverse Compton scattering may be operative, at least in some part of the system. Another possibility is that the sites of particle acceleration may be different for flaring and non-flaring events such as in the microquasar model the flaring radiation may come from hot spots sitting above the black hole while steady state emissions are due to the jets.
In this paper, we show that the zero-knowledge construction for Hamiltonian cycle remains secure against quantum adversaries in the relativistic setting. Our main technical contribution is a tool for studying the action of consecutive measurements on a quantum state which in turn gives upper bounds on the value of some entangled games. This allows us to prove the security of our protocol against quantum adversaries. We also prove security bounds for the (single-round) relativistic string commitment and bit commitment in parallel against quantum adversaries. As an additional consequence of our result, we answer an open question from [Unr12] and show tight bounds on the quantum knowledge error of some $\Sigma$-protocols.
We present a comprehensive mathematical study of the Magneto-Telluric (MT) method, on bounded domain in $\mathbb{R}^3$. We show that electrical conductivity and magnetic permeability, assumed to be $C^2$, can be uniquely recovered from MT data measured on the boundary of the domain. The proof is based on the construction of complex geometric optics solutions. Furthermore, we obtain a unique determination result in the case when the MT data are measured only on an open subset of the boundary. Here, we assume that the part of the boundary inaccessible for measurements is a subset of a sphere.
The main result of this work is to obtain the exponential decay of the solutions of a piezoelectric beam model with magnetic effect and delay term. The dampings are inserted into the equation of longitudinal displacement. The terms of damping, whose weight associated with them varies over time, are of the friction type, and one of them has delay. This work will also address the issue of existence and uniqueness of solution for the model.
Key role of orbital degree of freedom to understand the magnetic structure of uranium compounds is discussed from a microscopic viewpoint by focusing on typical examples such as UMGa$_5$ (M=Ni and Pt) and the mother compound UGa$_3$. By analyzing an orbital degenerate Hubbard model constructed from the $j$-$j$ coupling scheme in the cubic system, we obtain the phase diagram including several kinds of magnetic states. Especially, in the parameter region corresponding to actual uranium compounds, the phase diagram suggests successive transitions among paramagnetic, magnetic metallic, and insulating N\'eel states, consistent with the experimental results for AuCu$_3$-type uranium compounds. Furthermore, taking account of tetragonal effects such as level splitting and reduction of hopping amplitude along the z-axis, an orbital-based scenario is proposed to understand the change in the magnetic structure from G- to A-type antiferromagnetic phases, experimentally observed in UNiGa$_5$ and UPtGa$_5$.
We study two Weyl semimetal generalizations in five dimensions (5d) which have Yang monopoles and linked Weyl surfaces in the Brillouin zone, respectively, and carry the second Chern number as a topological number. In particular, we show a Yang monopole naturally reduces to a Hopf link of two Weyl surfaces when the $\mathbf{TP}$ (time-reversal combined with space-inversion) symmetry is broken. We then examine the phase transition between insulators with different topological numbers in 5d. In analogy to the 3d case, 5d Weyl semimetals emerge as intermediate phases during the topological phase transition.
We consider the three-dimensional incompressible magnetohydrodynamics (MHD) equations in a bounded domain with small volume and free moving surface boundary. We establish a priori estimate for solutions with minimal regularity assumptions on the initial data in Lagrangian coordinates. In particular, due to the lack of the Cauchy invariance for MHD equations, the smallness assumption on the fluid domain is required to compensate a loss of control of the flow map. Moreover, we show that the magnetic field has certain regularizing effect which allows us to control the vorticity of the fluid and that of the magnetic field. To the best of our knowledge this is the first result that focuses on the low regularity solution for incompressible free-boundary MHD equations.
In this paper we consider the Muskat problem describing the motion of two unbounded immiscible fluid layers with equal viscosities in vertical or horizontal two-dimensional geometries. We first prove that the mathematical model can be formulated as an evolution problem for the sharp interface separating the two fluids, which turns out to be, in a suitable functional analytic setting, quasilinear and of parabolic type. Based upon these properties, we then establish the local well-posedness of the problem for arbitrary large initial data and show that the solutions become instantly real-analytic in time and space. Our method allows us to choose the initial data in the class $H^s,$ $s\in(3/2,2)$, when neglecting surface tension, respectively in $H^s,$ $s\in(2,3),$ when surface tension effects are included. Besides, we provide new criteria for the global existence of solutions.
We present high spatial resolution CO(1-0) mapping of the luminous infrared galaxy NGC6240 obtained with the IRAM - Plateau de Bure Interferometer. This source is a well-known early-stage merging system hosting two AGN. We find a broad CO(1-0) line profile, with maximum velocity 800 km/s and FWZI=1400 km/s, and displaying several kinematic components, revealing the complexity of the gas dynamics in this system. We detect a blueshifted CO emission with velocity in the range -200 and -500 km/s, peaked around the southern AGN, at the same position where the H2 outflow is located, and with a mass loss rate of ~500 Msun/yr. We interpret this blueshifted component as a outflow, originating from the southern nucleus. The spatial and spectral match strongly suggests that the CO outflow is connected to the H2 superwind located around the southern nucleus, and to the large scale CO outflow, with similar velocities, extended on scales of 10 kpc. The large mass loading factor (dM/dt /SFR ~ 10) of the molecular gas suggests that the outflow is likely driven by both SNa winds and the radiation of the southern AGN. We discovered a nuclear, redshifted CO emission peaking in the mid point of the two nuclei, as it is the case for the CO emission at the systemic velocity. The large velocity dispersion, which reaches its maximum (~500 Km/s) in the mid point between the two nuclei, suggests that the gas might be highly turbulent in this region, although the presence of an unresolved rotation component cannot be ruled out.
We show that the equivariant Chow cohomology ring of a toric variety is naturally isomorphic to the ring of integral piecewise polynomial functions on the associated fan. This gives a large class of singular spaces for which localization holds in equivariant Chow cohomology with integer coefficients. We also compute the equivariant Chow cohomology of toric prevarieties and general complex hypertoric varieties in terms of piecewise polynomial functions.
Dynamical mean-field theory (DMFT) is one of the most widely-used methods to treat accurately electron correlation effects in ab-initio real material calculations. Many modern large-scale implementations of DMFT in electronic structure codes involve solving a quantum impurity model with a Continuous-Time Quantum Monte Carlo (CT-QMC) solver. The main advantage of CT-QMC is that, unlike standard quantum Monte Carlo approaches, it is able to generate the local Green's functions of the correlated system on an arbitrarily fine imaginary time grid, and is free of any systematic errors. In this work, we extend a hybrid QMC solver proposed by Khatami et al. and Rost et al. to a multi-orbital context. This has the advantage of enabling impurity solver QMC calculations to scale linearly with inverse temperature and permit its application to d and f band materials. In addition, we present a novel Green's function processing scheme which generates accurate quasi-continuous imaginary time solutions of the impurity problem which overcome errors inherent to standard QMC approaches. This solver and processing scheme are incorporated into a full DFT+DMFT calculation using the CASTEP DFT code. Benchmark calculations for strontium vanadate properties are presented.
We construct a Liouville superconformal field theory with eight real supercharges in four dimensions. The Liouville superfield is an $\mathcal{N}=2$ chiral superfield with sixteen bosonic and sixteen fermionic component fields. Its lowest component is a log-correlated complex scalar field whose real part carries a background charge. The theory is non-unitary with a continuous spectrum of scaling dimensions. We study its quantum dynamics on the supersymmetric 4-sphere and show that the classical background charge is not corrected quantum mechanically. We calculate the super-Weyl anomaly coefficients and find that $c$ vanishes, while $a$ is negative and depends on the background charge. We derive an integral expression for the correlation functions of superfield vertex operators in $\mathcal{N}=2$ superspace and analyze them in the semiclassical approximation by using a quaternionic formalism for the $\mathcal{N}=2$ superconformal algebra.