Miracle-dz/UniFAR-FTUs huggingface dataset:
The Redshift Dependence of the Alcock–Paczynski Effect: Cosmological Constraints from the Current and Next Generation Observations

The tomographic Alcock–Paczynski (AP) test is a robust large-scale structure (LSS) measurement that receives little contamination from the redshift space distortion. It has placed tight cosmological constraints by using small and intermediate clustering scales of the LSS data. However, previous works have neglected the cross-correlation among different redshift bins, which could cause the statistical uncertainty being underestimated by ∼20%. In this work, we further improve this method by including this multi-redshift’s full correlation. We apply it to the SDSS DR12 galaxies sample and find out that, for ΛCDM, the combination of AP with the Planck+BAO data set slightly reduces (within 1σ) Ωm to 0.304 ± 0.007 (68.3% CL). This then leads to a larger H0 and also mildly affects Ωb h2 and ns as well as the derived parameters z*, r*, and zre but not τ, As, and σ8. For the flat wCDM model, our measurement gives Ωm = 0.301 ± 0.010 and w = −1.090 ± 0.047, where the additional AP measurement reduces the error budget by ∼25%. When including more parameters into the analysis, the AP method also improves the constraints on Ωk, , and Neff by 20%–30%. Early universe parameters such as and r, however, are unaffected. Assuming the dark energy equation of state , the Planck+BAO+SNe Ia+H0+AP data sets prefer a dynamical dark energy at ≈1. 5σ CL. Finally, we forecast the cosmological constraints expected from the DESI galaxy survey and find that combining AP with the CMB+BAO method would improve the w0–wa constraint by a factor of ∼10.
Harmonic QPOs and Thick Accretion Disk Oscillations in the BL Lacertae Object AO 0235+164

Periodic outbursts are observed in many active galactic nuclei (AGNs) and are usually explained with a supermassive black hole binary (SMBHB) scenario. However, multiple periods are observed in some AGNs and cannot be explained in this way. Here we analyze the periodicity of the radio light curves of AO 0235+164 at multiple frequencies and report the discovery of six quasi-periodic oscillations (QPOs) in the integer frequency ratio 1 : 2 : 3 : 4 : 5 : 6, of which the second, with period P2 = 5.46 ± 0.47 yr, is the strongest. We fit the radio light curves and show that the initial phases of the six QPOs have differences of 0 or π relative to each other. We suggest a harmonic relationship among the QPOs. The centroid frequency, relative strength, harmonic relationship, and relative initial phases of the QPOs are independent of radio frequency. The harmonic QPOs are likely due to quasi-periodic injection of plasma from an oscillating accretion disk into the jet. We estimate a supermassive black hole mass of MBH ≃ (4.72 ± 2.04) × 108 M☉ and an accretion rate ≃ 0.007. With knowledge of the accretion disk, this implies that the inner region of the AO 0235+164 accretion disk is a radiatively inefficient accretion flow. The oscillatory accretion is due to p-mode oscillations of the thick disk, probably excited by a SMBHB. Theoretical predictions for the fundamental oscillation frequency and the harmonics show good consistency with the observations. Harmonic QPOs would disappear if the thick disk became geometrically thin as the result of an increase in accretion rate. We discuss the observations of AO 0235+164 in the context of the SMBHB-thick disk oscillation scenario.
Effects of in-plane stiffness and charge transfer on thermal expansion of monolayer transition metal dichalcogenide*

The temperature dependence of lattice constants is studied by using first-principles calculations to determine the effects of in-plane stiffness and charge transfer on the thermal expansions of monolayer semiconducting transition metal dichalcogenides. Unlike the corresponding bulk material, our simulations show that monolayer MX2 (M = Mo and W; X = S, Se, and Te) exhibits a negative thermal expansion at low temperatures, induced by the bending modes. The transition from contraction to expansion at higher temperatures is observed. Interestingly, the thermal expansion can be tailored regularly by alteration of the M or X atom. Detailed analysis shows that the positive thermal expansion coefficient is determined mainly by the in-plane stiffness, which can be expressed by a simple relationship. Essentially the regularity of this change can be attributed to the difference in charge transfer between the different elements. These findings should be applicable to other two-dimensional systems.
How Initial Size Governs Core Collapse in Globular Clusters

Globular clusters (GCs) in the Milky Way exhibit a well-observed bimodal distribution in core radii separating the so-called core-collapsed and non-core-collapsed clusters. Here, we use our Hénon-type Monte Carlo code, CMC, to explore initial cluster parameters that map into this bimodality. Remarkably, we find that by varying the initial size of clusters (specified in our initial conditions in terms of the initial virial radius, rv) within a relatively narrow range consistent with the measured radii of young star clusters in the local universe (rv ≈ 0.5–5 pc), our models reproduce the variety of present-day cluster properties. Furthermore, we show that stellar-mass black holes (BHs) play an intimate role in this mapping from initial conditions to the present-day structural features of GCs. We identify “best-fit” models for three GCs with known observed BH candidates, NGC 3201, M22, and M10, and show that these clusters harbor populations of ∼50–100 stellar-mass BHs at present. As an alternative case, we also compare our models to the core-collapsed cluster NGC 6752 and show that this cluster likely contains few BHs at present. Additionally, we explore the formation of BH binaries in GCs and demonstrate that these systems form naturally in our models in both detached and mass-transferring configurations with a variety of companion stellar types, including low-mass main-sequence stars, white dwarfs, and sub-subgiants.
Ground-based photometry of the 21-day Neptune HD106315c

Space-based transit surveys such as K2 and TESS allow the detection of small transiting planets with orbital periods beyond 10 days. Few of these warm Neptunes are currently known around stars bright enough to allow for detailed follow-up observations dedicated to their atmospheric characterization. The 21-day period and 3.95 $R_\oplus$ planet HD106315c has been discovered based on the observation of two of its transits by K2. We have observed HD106315 using the 1.2m Euler telescope equipped with the EulerCam camera on two instances to confirm the transit using broad band photometry and refine the planetary period. Based on two observed transits of HD106315c, we detect its $\sim$1 mmag transit and obtain a precise measurement of the planetary ephemerids, which are critical for planning further follow-up observations. We have used the attained precision together with the predicted yield from the TESS mission to evaluate the potential for ground-based confirmation of Neptune-sized planets found by TESS. We find that 1-meter-class telescopes on the ground equipped with precise photometers could substantially contribute to the follow-up of 162 TESS candidates orbiting stars with magnitudes of $V \leq 14$. Out of these, 74 planets orbit stars with $V \leq 12$ and 12 planets orbit $V \leq 10$, which makes these candidates high-priority objects for atmospheric characterization with high-end instrumentation.
Networks of self-avoiding chains and Ogden-type constitutive equations for elastomers

An expression is derived for the strain energy of a polymer chain under an arbitrary three-dimensional deformation with finite strains. For a Gaussian chain, this expression is reduced to the conventional Moony--Rivlin constitutive law, while for non-Gaussian chains it implies novel constitutive relations. Based on the three-chain approximation, explicit formulas are developed for the strain energy of a chain modeled as a self-avoiding random walk. In the case of self-avoiding chains with stretched-exponential distribution function of end-to-end vectors, the strain energy density of a network is described by the Ogden law with only two material constants. For the des Cloizeaux distribution function, the constitutive equation involves three adjustable parameters. The governing equations are verified by fitting observations on uniaxial tension, uniaxial compression and biaxial tension of elastomers. Good agreement is demonstrated between the experimental data and the results of numerical analysis. An analytical formula is derived for the ratio of the Young's modulus of a self-avoiding chain to that of a Gaussian chain. It is found that the elastic modulus per chain in the Ogden network exceeds that in a Gaussian network by a factor of three, whereas the elastic modulus of a chain with the generalized stretched exponential distribution function equals about half of the modulus of a Gaussian chain.
A Theory of Cooperative Phenomena

A new method of approximation for order-disorder phenomena is developed. In Sec. A, the method is explained for the one-dimensional Ising lattice. Sections B and C cover the approximations already known, such as those of Bethe (Sec. B) and of Kramers-Wannier (Sec. C), which are shown to be derived as special cases of the method with suitable choices of variables. In Sec. D, an improved treatment is explained for the three-dimensional simple cubic Ising lattice. This approximation is found to agree with the rigorous expansion of the partition function up to the fourth moment by Kirkwood's moment method, so far as the disordered state is concerned. In Sec. E the general formula for the entropy is given. In Sec. H an improved treatment of the face-centered lattice (Ising model) is given.
High-Latitude Radio Emission in a Sample of Edge-on Spiral Galaxies

We have mapped 16 edge-on galaxies at 20 cm using the Very Large Array in its C configuration, and a subset of these galaxies in the D configuration at 6 and/or 20 cm, in a search for extended (≳1 kpc) radio continuum emission above and below the plane. For five galaxies, we could form spectral index, energy, and magnetic field maps (assuming minimum energy). While the galaxies were partly chosen by radio flux density, they span a variety of star formation rates (SFRs), and only six might be considered "starburst" galaxies. A range of Hubble type and degree of isolation are also represented. The galaxies largely fall on the FIR–radio continuum correlation. They also display a correlation between IR surface brightness and warmth, extending the previously observed relation of Lehnert & Heckman to galaxies with lower star formation rates. We find that all but one galaxy show evidence for nonthermal high-latitude radio continuum emission, suggesting that cosmic-ray (CR) halos are common in star-forming galaxies. Of these, eight galaxies are new detections. The high-latitude emission is seen over a variety of spatial scales and in discrete and/or smooth features. In some cases, discrete features are seen on large scales, suggesting that smooth radio halos may consist, in part, of discrete features combined with low spatial resolution. In general, the discrete features emanate from the disk, but estimates of CR diffusion lengths suggest that diffusion alone is insufficient to transport the particles to the high latitudes seen (>15 kpc in one case). Thus CRs likely diffuse through low-density regions and/or are assisted by other mechanisms (e.g., winds). We searched for correlations between the prevalence of high-latitude radio emission and a number of other properties, including the global SFR, supernova input rate per unit star-forming area, A, and environment, and do not find clear correlations with any of these properties. A subset of the data allows, at best, for only a weak correlation with A. Our one nondetection (NGC 4517), however, occurs at a threshold level consistent with that found by Dahlem, Lisenfeld, & Golla. The lack of a good correlation with star formation indicators could be the result of the different timescales for star formation processes compared with the duration of the radio emission. Correlations with other properties, such as environment, are more difficult to assess. However, a few isolated galaxies display strong radio halos, indicating that an interaction is not necessary to produce the extraplanar emission.
Word‐final devoicing in German and the effects of phonetic and sentential contexts

The present study investigated the possible effects that place of articulation of the final stop, the phonetic environment of the target word, and sentential position might have on vowel duration, voicing into closure, and closure duration as acoustic correlates of underlying voicing. The results of the study replicate the findings that word‐final devoicing is non‐neutralizing in German. However, the results also show that the temporal correlates of underlying voicing are different for dental and velar stops and are different for lexical items. Moreover, for the dental stops, vowel duration, and voicing into closure as correlates of underlying voicing are not independent of phonetic or sentential contexts. The overall results suggest that the phonetic rules necessary to implement word‐final stops in German must be sensitive to place of articulation, surrounding phonetic and sentential contexts, and even individual lexical items. [Supported by NIH Training Grant T32 NS‐7134. ]
Non-flipping 13C spins near an NV center in diamond: hyperfine and spatial characteristics by density functional theory simulation of the C510[NV]H252 cluster

Single NV centers in diamond coupled by hyperfine interaction (hfi) to neighboring 13C nuclear spins are now widely used in emerging quantum technologies as elements of quantum memory adjusted to a nitrogen-vacancy (NV) center electron spin qubit. For nuclear spins with low flip-flop rate, single shot readout was demonstrated under ambient conditions. Here we report on a systematic search for such stable NV−13C systems using density functional theory to simulate the hfi and spatial characteristics of all possible NV−13C complexes in the H-terminated cluster C510[NV]-H252 hosting the NV center. Along with the expected stable ‘NV-axial−13C’ systems wherein the 13C nuclear spin is located on the NV axis, we found for the first time new families of positions for the 13C nuclear spin exhibiting negligible hfi-induced flipping rates due to near-symmetric local spin density distribution. Spatially, these positions are located in the diamond bilayer passing through the vacancy of the NV center and being perpendicular to the NV axis. Analysis of available publications showed that, apparently, some of the predicted non-axial near-stable NV−13C systems have already been observed experimentally. A special experiment performed on one of these systems confirmed the prediction made.
A Kinematical Detection of Two Embedded Jupiter-mass Planets in HD 163296

We present the first kinematical detection of embedded protoplanets within a protoplanetary disk. Using archival Atacama Large Millimetre Array (ALMA) observations of HD 163296, we demonstrate a new technique to measure the rotation curves of CO isotopologue emission to sub-percent precision relative to the Keplerian rotation. These rotation curves betray substantial deviations caused by local perturbations in the radial pressure gradient, likely driven by gaps carved in the gas surface density by Jupiter-mass planets. Comparison with hydrodynamic simulations shows excellent agreement with the gas rotation profile when the disk surface density is perturbed by two Jupiter-mass planets at 83 and 137 au. As the rotation of the gas is dependent upon the pressure of the total gas component, this method provides a unique probe of the gas surface density profile without incurring significant uncertainties due to gas-to-dust ratios or local chemical abundances that plague other methods. Future analyses combining both methods promise to provide the most accurate and robust measures of embedded planetary mass. Furthermore, this method provides a unique opportunity to explore wide-separation planets beyond the mm continuum edge and to trace the gas pressure profile essential in modeling grain evolution in disks.
The Very Low Mass Component of the Gliese 105 System

Multiple-epoch, multicolor images of the astrometric binary Gliese 105A and its very low mass companion Gliese 105C have been obtained using the Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2) and near-infrared camera and multiobject spectrometer (NICMOS). The optical and near-infrared colors of Gl 105C strongly suggest a spectral type of M7 V for that star. Relative astrometric measurements spanning 3 yr reveal the first evidence of Gl 105C's orbital motion. Previous long-term astrometric studies at Sproul and McCormick Observatories have shown that the period of Gl 105A's perturbation is ∼60 yr. To satisfy both the observed orbital motion and Gl 105A's astrometric period, Gl 105C's orbit must have an eccentricity of ∼0.75 and a semimajor axis of ∼15 AU. Measurements of Gl 105A's radial velocity over 12 yr show a linear trend with a slope of 11.3 m s-1 yr-1, which is consistent with these orbital constraints and a nearly face-on orbit. As no other faint companions to Gl 105A have been detected, we conclude that Gl 105C is probably the source of the 60 yr astrometric perturbation.
Electronic states and quantum transport in double-wall carbon nanotubes

The electronic states and transport properties of double-wall carbon nanotubes without impurities are studied in a systematic manner. It is revealed that scattering in the bulk is negligible and the number of channels determines the average conductance. In the case of general incommensurate tubes, separation of degenerated energy levels due to intertube transfer is suppressed in the energy region higher than the Fermi energy but not in the energy region lower than that. Accordingly, in the former case, there are few effects of intertube transfer on the conductance, while in the latter case, separation of degenerated energy levels leads to large reduction of the conductance. It is also found that in some cases antiresonance with edge states in inner tubes causes an anomalous conductance quantization ${G=e}^{2}/\ensuremath{\pi}\ensuremath{\Elzxh},$ near the Fermi energy.
Static solitary waves as limits of discretization: a plausible argument

We investigate special limits of the classical Euler buckling problem, arguing that the solution–family ‘imitating’ (without mass forces) the propagation of a dynamic solitary wave cannot be obtained as a limit from Euler's problem, only from its discretized version. Although we can not prove this claim rigorously, we prove other related statements that make the conjecture strongly plausible. Our results yield access to some open questions related to the discretized problem; also they show some new aspects of spatially chaotic behaviour.
Local asymptotics for regression splines and confidence regions

In this paper, we study the local behavior of regression splines. In particular, explicit expressions for the asymptotic pointwise bias and variance of regression splines are obtained. In addition, asymptotic normality for regression splines is established, leading to the construction of approximate confidence intervals and confidence bands for the regression function.
Accelerating crystal structure prediction by machine-learning interatomic potentials with active learning

We propose a methodology for crystal structure prediction that is based on the evolutionary algorithm USPEX and the machine-learning interatomic potentials actively learning on-the-fly. Our methodology allows for an automated construction of an interatomic interaction model from scratch, replacing the expensive density functional theory (DFT) and giving a speedup of several orders of magnitude. Predicted low-energy structures are then tested on DFT, ensuring that our machine-learning model does not introduce any prediction error. We tested our methodology on prediction of crystal structures of carbon, high-pressure phases of sodium, and boron allotropes, including those that have more than 100 atoms in the primitive cell. All the the main allotropes have been reproduced, and a hitherto unknown 54-atom structure of boron has been predicted with very modest computational effort.
9.7 μm Silicate Features in Active Galactic Nuclei: New Insights into Unification Models

We describe observations of 9.7 μm silicate features in 97 AGNs, exhibiting a wide range of AGN types and of X-ray extinction toward the central nuclei. We find that the strength of the silicate feature correlates with the H I column density estimated from fitting the X-ray data, such that low H I columns correspond to silicate emission, while high columns correspond to silicate absorption. The behavior is generally consistent with unification models in which the large diversity in AGN properties is caused by viewing-angle-dependent obscuration of the nucleus. Radio-loud AGNs and radio-quiet quasars follow roughly the correlation between H I columns and the strength of the silicate feature defined by Seyfert galaxies. The agreement among AGN types suggests a high-level unification with similar characteristics for the structure of the obscuring material. We demonstrate the implications for unification models qualitatively with a conceptual disk model. The model includes an inner accretion disk (<0.1 pc in radius), a middle disk (0.1-10 pc in radius) with a dense diffuse component and with embedded denser clouds, and an outer clumpy disk (10-300 pc in radius).
On the rate of convergence of waiting times

Let K(y) be a known distribution function on (−∞, ∞) and let {Fn(y), n = 0, 1,…} be a sequence of unknown distribution functions related by subject to the initial condition If the sequence {Fn(y)} converges to a distribution function F(y) then F(y) satisfies the Wiener-Hopf equation
NuStar Hard X-Ray View of Low-luminosity Active Galactic Nuclei: High-energy Cutoff and Truncated Thin Disk

We report the analysis of simultaneous XMM-Newton+Nuclear Spectroscopic Telescope Array (NuSTAR) observations of two low-luminosity active galactic nuclei (LLAGNs), NGC 3998 and NGC 4579. We do not detect any significant variability in either source over the ∼3 day length of the NuSTAR observations. The broadband 0.5–60 keV spectrum of NGC 3998 is best fit with a cutoff power law, while the one for NGC 4579 is best fit with a combination of a hot thermal plasma model, a power law, and a blend of Gaussians to fit an Fe complex observed between 6 and 7 keV. Our main spectral results are the following: (1) neither source shows any reflection hump with 3σ reflection fraction upper limits of and for NGC 3998 and NGC 4579, respectively; (2) the 6–7 keV line complex in NGC 4579 could be fit with either a narrow Fe K line at 6.4 keV and a moderately broad Fe xxv line or with three relatively narrow lines, which include contribution from Fe xxvi; (3) the NGC 4579 flux is 60% brighter than previously detected with XMM-Newton, accompanied by a hardening in the spectrum; (4) we measure a cutoff energy keV in NGC 3998, which represents the lowest and best constrained high-energy cutoff ever measured for an LLAGN; (5) the NGC 3998 spectrum is consistent with a Comptonization model with either a sphere (τ ≈ 3 ± 1) or slab (τ ≈ 1.2 ± 0.6) geometry, corresponding to plasma temperatures between 20 and 150 keV. We discuss these results in the context of hard X-ray emission from bright AGNs, other LLAGNs, and hot accretion flow models.