ShantanuT01/DACTYL-Pretraining huggingface dataset:
In the paper by Hasegawa, Hagino and Tanimura (HHT) [Phys. Lett. B 808 (2020) 135693, arXiv:2006.06944], they concluded that quantum tunneling was simulated by a time-dependent generator coordinate method (TDGCM). In contrast, difficulties of TDGCM in describing quantum tunneling were pointed out by Ono in the paper [Phys. Lett. B 826 (2022) 136931, arXiv:2201.02966]. Recently, HHT submitted a comment [arXiv:2202.00513v1], by which they appear to give some counterarguments to Ono's paper. Here I examine their arguments, reviewing the main points of Ono's paper. The confusion in HHT's arguments may be mostly resolved by recognizing how the wave packets interfere with each other when they are coherently superposed.
Here we present the results of a wide-field (~36 sq. deg.) near-infrared (ZYJHK) survey of the Praesepe cluster using the Data Release 9 of the UKIRT Infrared Deep Sky Survey Galactic Clusters Survey. We selected cluster candidates of Praesepe based on astrometry and photometry. With our candidate list, we have obtained the luminosity function of Praesepe in the Z and J bands, and we have derived the mass function of Praesepe from 0.6 down to 0.072 Msol. Moreover, we have estimated the binarity of the Praesepe members in the 0.45-0.07 Msol mass range and as well as their variability.
We have calculated the cross section of the process e^+e^- \to \gamma\gamma \to b\bar{b} in the littlest Higgs model with T parity (LHT). We find that, for the favorable parameters, the total cross section \sigma(e^+e^- \to \gamma\gamma \to b\bar{b}) is sensitive to the breaking scale f, mixing parameter x_L, the masses of the mirror quarks m_{Hi}, and the relative correction of the LHT model is a few percent to dozens of percent. The cross section is significantly larger than the corresponding results in the standard model and in the other typical new physics models. Therefore the prediction in the LHT model is quite different from the predictions in other new physics models and such a process is really interesting in searching for the signs of the LHT model.
In a private communication, K. Ono conjectured that any mock theta function of weight 1/2 or 3/2 can be congruent modulo a prime $p$ to a weakly holomorphic modular form for just a few values of $p$. In this paper we describe when such a congruence occurs. More precisely we show that it depends on the $p$-adic valuation of the mock theta function itself. In order to do so, we construct a family of mock theta functions in terms of derivatives of the Appell sum, which have a special Fourier expansion at infinity.
The galaxy pairwise velocity dispersion (PVD) can provide important tests of non-standard gravity and galaxy formation models. We describe measurements of the PVD of galaxies in the Galaxy and Mass Assembly (GAMA) survey as a function of projected separation and galaxy luminosity. Due to the faint magnitude limit ($r < 19.8$) and highly-complete spectroscopic sampling of the GAMA survey, we are able to reliably measure the PVD to smaller scales ($r_\bot = 0.01$ Mpc/h) than previous work. The measured PVD at projected separations $r_\bot <~ 1$ Mpc/h increases near-monotonically with increasing luminosity from $\sigma \approx 200$ km/s at $M_r = -17$ mag to $\sigma \approx 600$ km/s at $M_r \approx -22$ mag. Analysis of the Gonzalez-Perez (2014) GALFORM semi-analytic model yields no such trend of PVD with luminosity: the model over-predicts the PVD for faint galaxies. This is most likely a result of the model placing too many low-luminosity galaxies in massive halos.
Different theoretical models predict VHE gamma-ray emission to arise in tight binary star systems (high mass-loss and high wind speeds), which has not been confirmed experimentally so far. Here we present the first bounds on the VHE emission from two isolated Wolf-Rayet star binaries, WR147 and WR146, obtained with the MAGIC telescope.
We present a near-infrared spectroscopic survey of narrow-line Seyfert 1 galaxies in the southern hemisphere (using the SOFI instrument on the ESO-NTT telescope), sampled from optical surveys. We examine the kinematics of the broad-line region, probed by the emission line width of hydrogen (Pa$\alpha$ and H$\beta$). We observed 57 objects, of which we could firmly measure Pa$\alpha$ in 49 cases. We find that a single Lorentzian fit (preferred on theoretical grounds) is preferred over multi-component Gaussian fits to the line profiles; a lack of narrow-line region emission, overwhelmed by the pole-on view of the broad line region (BLR) light, supports this. We recompute the catalog black hole (BH) mass estimates, using the values of FWHM and luminosity of H$\beta$, both from catalog values and re-fitted Lorentzian values. We find a relationship slope greater than unity compared to the catalog values. We ascribe this to contamination by galactic light or difficulties with line flux measurements. However, the comparison of masses computed by the fitted Lorentzian and Gaussian measurements show a slope close to unity. Comparing the BH masses estimated from both Pa$\alpha$ and H$\beta$, the line widths and fluxes shows deviations from expected; in general, however, the computed BH masses are comparable. We posit a scenario where an intermixture of dusty and dust-free clouds (or alternately a structured atmosphere) differentially absorbs the line radiation of the BLR, due to dust absorption and hydrogen bound-free absorption.
Let $X_1, \ldots , X_n$ be i.i.d. random vectors in $\mathbb{R}^d$ with $\|X_1\| \le \beta$. Then, we show that $\frac{1}{\sqrt{n}}(X_1 + \ldots + X_n)$ converges to a Gaussian in quadratic transportation (also known as "Kantorovich" or "Wasserstein") distance at a rate of $O\left( \frac{\sqrt{d} \beta \log n}{\sqrt{n}} \right)$, improving a result of Valiant and Valiant. The main feature of our theorem is that the rate of convergence is within $\log n$ of optimal for $n, d \rightarrow \infty$.
We give sharp lower bounds for the postulation of the nodes of a general plane projection of a smooth connected curve C in P^r and we study the relationships with the geometry of the embedding. Strict connections with Castelnuovo's theory and Halphen's theory are shown.
We present a simple information-disturbance tradeoff relation valid for any general measurement apparatus: The disturbance between input and output states is lower bounded by the information the apparatus provides in distinguishing these two states.
Using a combination of local density functional theory and cluster exact diagonalization based dynamical mean field theory, we calculate many body electronic structures of several Mott insulating oxides including undoped high T_{c} materials. The dispersions of the lowest occupied electronic states are associated with the Zhang-Rice singlets in cuprates and with doublets, triplets, quadruplets and quintets in more general cases. Our results agree with angle resolved photoemission experiments including the decrease of the spectral weight of the Zhang--Rice band as it approaches k=0.
Near-ultraviolet (NUV) spectroscopic studies have suggested that passively evolving massive, early-type galaxies host sub-one percent fractions of young stars in their innermost regions. We shed light on the origin of these stars by analysing NGC 1277, a widely studied nearby prototypical massive compact relic galaxy. These are rare galaxies that have survived without experiencing significant size evolution via accretion and mergers since their formation at high redshift. We obtain a spectrum in the UV range within the central 1 kpc region of NGC 1277. We compare a carefully selected set of optical and NUV line-strengths to model predictions with star formation histories characteristic of massive galaxies. We find a 0.8% mass fraction of young stars in the centre of NGC 1277, similar to that found in massive early-type galaxies. Given the limited accretion history of NGC 1277, these results favour an intrinsic, in-situ, process triggering star formation at later epochs. Our results suggest a general constraint on the amount of young stars in the cores of massive early-type galaxies. This amount should be assumed as an upper limit for the young stellar contribution in massive galaxies, as there might be present other contributions from evolved stars.
Absence of level repulsion between extended states in random non-Hermitian systems is demonstrated. As a result, the general Wigner-Dyson distributions of level spacing of diffusive metals in the usual Hermitian systems is replaced by the Poisson distribution for quasiparticle level spacing of non-Hermitian disordered metals in the thermodynamic limit of infinite system size. This is a very surprising result because Poisson statistics is universally true for the Anderson insulators where energy eigenstates do not overlap with each other so that energy levels are independent from each other.For disordered metals where different eigenstates overlap with each other, one should expect different levels trying to stay away from each other so that the Poisson distribution should not apply there. Our results show that the larger non-Hermitian energy (dissipation) can invalidate level repulsion principle that holds dearly in quantum mechanics. Thus, our theory provides a unified picture for recent discovery of so called "level attraction" in various systems. It provides also a theoretical basis for manipulating energy levels.
We study the interaction of the early spherical GC wind powered by Type II supernovae (SNe II) with the surrounding ambient medium consisting of the gaseous disk of a star forming galaxy at redshift z ~> 2. The bubble formed by the wind eventually breaks out of the disk, and most of the wind moves directly out of the galaxy and is definitively lost. The fraction of the wind moving nearly parallel to the galactic plane carves a hole in the disk which will contract after the end of the SN activity. During the interval of time between the end of the SN explosions and the "closure" of the hole, very O-poor stars (the Extreme population) can form out of the super-AGB (asymptotic giant branch) ejecta collected in the GC center. Once the hole contracts, the AGB ejecta mix with the pristine gas, allowing the formation of stars with an oxygen abundance intermediate between that of the very O-poor stars and that of the pristine gas. We show that this mechanism may explain why Extreme populations are present only in massive clusters, and can also produce a correlation between the spread in helium and the cluster mass. Finally, we also explore the possibility that our proposed mechanism can be extended to the case of multiple populations showing bimodality in the iron content, with the presence of two populations characterized by a small difference in [Fe/H]. Such a result can be obtained taking into account the contribution of delayed SN II.
A finite spin system invariant under a symmetry group G is a very illustrative example of the finite group action on a set of mappings f:X->Y. In the case of spin systems X is a set of spin carriers and Y contains 2s+1 z-components -s<=m<=s for a given spin number s. Orbits and stabilizers are used as additional indices of the symmetry adapted basis. Their mathematical nature does not lead to smaller eigenproblems, but they label states in a systematic way. Some combinatorial and group-theoretical structures, like double cosets and transitive representations, appear in a natural way. In such a system one can construct general formulas for vectors of symmetry adapted basis and matrix elements of operators commuting with the action of $G$ in the space of states. Considerations presented in this paper should be followed by detailed discussion of different symmetry groups (e.g. cyclic of dihedral ones) and optimal implementation of algorithms. The paradigmatic example, i.e. a finite spin system, can be useful in investigation of magnetic macromolecules.
We consider the gradient flow of a Ginzburg-Landau functional of the type \[ F_\varepsilon^{\mathrm{extr}}(u):=\frac{1}{2}\int_M \left|D u\right|_g^2 + \left|\mathscr{S} u\right|^2_g +\frac{1}{2\varepsilon^2}\left(\left|u\right|^2_g-1\right)^2\mathrm{vol}_g \] which is defined for tangent vector fields (here $D$ stands for the covariant derivative) on a closed surface $M\subseteq\mathbb{R}^3$ and includes extrinsic effects via the shape operator $\mathscr{S}$ induced by the Euclidean embedding of~$M$. The functional depends on the small parameter $\varepsilon>0$. When $\varepsilon$ is small it is clear from the structure of the Ginzburg-Landau functional that $\left|u\right|_g$ ''prefers'' to be close to $1$. However, due to the incompatibility for vector fields on $M$ between the Sobolev regularity and the unit norm constraint, when $\varepsilon$ is close to $0$, it is expected that a finite number of singular points (called vortices) having non-zero index emerges (when the Euler characteristic is non-zero). This intuitive picture has been made precise in the recent work by R. Ignat \& R. Jerrard [7]. In this paper we are interested the dynamics of vortices generated by $F_\varepsilon^{\mathrm{extr}}$. To this end we study the behavior when $\varepsilon\to 0$ of the solutions of the (properly rescaled) gradient flow of $F_\varepsilon^{\mathrm{extr}}$. In the limit $\varepsilon\to 0$ we obtain the effective dynamics of the vortices. The dynamics, as expected, is influenced by both the intrinsic and extrinsic properties of the surface $M\subseteq\mathbb{R}^3$.
Nature-occurring structures exhibiting unique topological features such as complex and gradient porosity has been the basis to create new materials and/or structures. Most studies have been focused on complex periodic porous structures but gradient porous ones have not been yet fully investigated for stable structural designs. In this work, we have proposed and tested a new approach to create cellular griding structures, in which the mass density varies from the center to the borders, i.e, a radial gradient. To create these new structures we exploited the topology of two carbon-based families with different pore sizes, the schwarzites, and schwarzynes. We created fully atomistic models that were translated into macroscale ones that were then 3D printed. The mechanical behavior of the gradient structures was investigated by molecular dynamics simulations and mechanical compression tests of the printed models. Our results show that their mechanical response can be engineered (for instance, in terms of energy absorption, ballistic performance, etc.) and can outperform their corresponding density uniform structures.
How many fair coin tosses to choose 1 of $n$ options with uniform probability? Although a probability problem, the solution is essentially number-theoretic, with special roles for Mersenne numbers, Fermat numbers, and the haupt exponent. We propose a bit-efficient scheme, prove optimality, derive the expected number of coin tosses $e[n]$, characterize its fractal structure, and develop sharp upper and lower bounds, both discrete and continuous. A minor but noteworthy corollary, with real-world examples, is that any lottery or simulation with finite budget of random bits will have a predictable pattern of lucky and unlucky numbers.
The spin ice compound Dy$_2$Ti$_2$O$_7$ is well-known to realise a three-dimensional Coulomb spin liquid with magnetically charged monopole excitations. Its fate at low temperatures, however, remains an intriguing open question. Based on a low-temperature analysis of the magnetic noise and diffuse neutron scattering under different cooling protocols, combined with extensive numerical modelling, we argue that upon cooling, the spins freeze into what may be termed a `structural magnetic glass', without an a priori need for chemical or structural disorder. Specifically, our model indicates the presence of frustration on two levels, first producing a near-degenerate constrained manifold inside which phase ordering kinetics is in turn frustrated. Our results suggest that spin ice Dy$_2$Ti$_2$O$_7$ provides one prototype of magnetic glass formation specifically, and a setting for the study of kinetically constrained systems more generally.
LIDAR point clouds and RGB-images are both extremely essential for 3D object detection. So many state-of-the-art 3D detection algorithms dedicate in fusing these two types of data effectively. However, their fusion methods based on Birds Eye View (BEV) or voxel format are not accurate. In this paper, we propose a novel fusion approach named Point-based Attentive Cont-conv Fusion(PACF) module, which fuses multi-sensor features directly on 3D points. Except for continuous convolution, we additionally add a Point-Pooling and an Attentive Aggregation to make the fused features more expressive. Moreover, based on the PACF module, we propose a 3D multi-sensor multi-task network called Pointcloud-Image RCNN(PI-RCNN as brief), which handles the image segmentation and 3D object detection tasks. PI-RCNN employs a segmentation sub-network to extract full-resolution semantic feature maps from images and then fuses the multi-sensor features via powerful PACF module. Beneficial from the effectiveness of the PACF module and the expressive semantic features from the segmentation module, PI-RCNN can improve much in 3D object detection. We demonstrate the effectiveness of the PACF module and PI-RCNN on the KITTI 3D Detection benchmark, and our method can achieve state-of-the-art on the metric of 3D AP.
We present optical spectroscopy and extensive $RI$ differential photometry of the double-lined eclipsing binary NSVS 02502726 (2MASS J08441103+5423473). Simultaneous solution of two-band light curves and radial velocities permits determination of precise emprical masses and radii for both components of the system. The analysis indicates that the primary and secondary components of NSVS 02502726 are in a circular orbit with 0.56-day orbital period and have stellar masses of M$_1$=0.714$\pm$0.019 \Msun, and M$_2$=0.347$\pm$0.012 \Msun. Both of the components have large radii, being R$_1$=0.67$\pm$0.01 \Rsun, and R$_2$=0.76$\pm$0.01 \Rsun. The principal parameters of the mass and radius of the component stars are found with an accuracy of 3% and 1%, respectively. The secondary component's radius is significantly larger than model predictions for its mass, similar to what is seen in almost all of the other well-studied low-mass stars which belong to double-lined eclipsing binaries. Strong H$_{\alpha}$ emission cores and considerable distortion at out-of-eclipse light curve in both $R$ and $I$ bandpasses, presumably due to dark spots on both stars, have been taken as an evidence of strong stellar activity. The distance to system was calculated as 173$\pm$8 pc from the $BVRIJHK$ magnitudes. The absolute parameters of the components indicate that both components are close to the zero-age main-sequence. Comparison with current stellar evolution models gives an age of 126 $\pm$30 Myr, indicating the stars are in the final stages of pre-main-sequence contraction.
Zirconium oxide(ZrO) is an important astrophysical molecule that defines the S-star classification class for cool giant stars. Accurate, empirical rovibronic energy levels, with associated labels and uncertainties, are reported for 9 low-lying electronic states of the diatomic 90Zr16O molecule. These 8088 empirical energy levels are determined using the Marvel (Measured Active Rotational-Vibrational Energy Levels) algorithm with 23 317 input assigned transition frequencies, 22 549 of which were validated. A temperature-dependent partition function is presented alongside updated spectroscopic constants for the 9 low-lying electronic states.
Neutrinos play a crucial role in many aspects of astrophysics and cosmology. Since they control the electron fraction, or equivalently neutron-to-proton ratio, neutrino properties impact yields of r-process nucleosynthesis. Similarly the weak decoupling temperature in the Big Bang Nucleosynthesis epoch is exponentially dependent on the neutron-to-proton ratio. In these conference proceedings, I briefly summarize some of the recent work exploring the role of neutrinos in astrophysics and cosmology.
Wide-field JHKs near-infrared observations covering an area of 1.8x1.8 sq. deg. centred on M33 were obtained using WFCAM at UKIRT. These data show a large population of intermediate-age asymptotic giant branch stars (AGB). We have used both C-type and M-type AGB stars to determine spatial variations in metallicity and mean age across the galaxy. We distinguished between C-type and M-type AGB stars from their location in the colour-magnitude diagram (J-Ks, Ks). The distribution of these stars is supported by a cross-identification between our sample and a catalogue of optically confirmed, long-period variable stars, as well as with the list of sources detected by Spitzer in the mid-infrared. We calculated the C/M ratio and the orientation of the galaxy in the sky, and compared the Ks magnitude distribution with theoretical distributions spanning a range of metallicities and star formation rates (SFRs). The C/M ratio surface map confirms a metallicity gradient in the galaxy corresponding to a spread in [Fe/H]=0.6 dex with substructures in the inner and outer galaxy. Magnitude and colour variations suggest orientation and extinction effects on the galaxy disc. Maps showing the distribution of mean age and metallicity obtained from the Ks method suggest that: the outer galaxy disc/halo is metal poorer than the nuclear region and metal-rich clumps in the inner galaxy change location with time. The average outer ring and nuclear stellar population is ~6 Gyr old while central regions are a few Gyr younger.
We find the current voltage characteristics of a 2DEG-S interface in magnetic field taking into account the surface roughness. Typically in experiments $L/2R_c\gtrsim 3$, where $L$ is the surface length and $R_c$ is the cyclotron radius. The conductance behaves in experiments usually as $G=g_0+g_1\cos(2\pi\nu+\delta_1)$; higher harmonics, $g_2\cos(4\pi\nu+\delta_2),...$, are hardly seen. Theories based on the assumption of the interface perfectness can hardly describe qualitatively the visibility of the condctance oscillations and the amplitudes of the harmonics: they predict $g_1\sim g_2\sim g_3,...$. Our approach with the surface roughness qualitatively agrees with experiments. It is shown how a disorder at a 2DEG-S interface suppresses the conductance oscillations with $\nu$.
We study the conditions of validity of generalized second law in phantom dominated era.
In this manifesto I review the status of standard BBN in light of recent observational data (e.g., QSO deuterium and Izotov etal. helium-4).
H. J. S. Smith proved Fermat's two-square theorem using the notion of palindromic continuants. In this paper we extend Smith's approach to proper binary quadratic form representations in some commutative Euclidean rings, including rings of integers and rings of polynomials over fields of odd characteristic. Also, we present new deterministic algorithms for finding the corresponding proper representations.
A real arithmetic function f is multiplicatively monotonous if f (mn) -- f (m) has constant sign for m, n positive integers. Properties and examples of such functions are discussed, with applications to positive hermitian Toeplitz-multiplicative determinants.
Let $f\colon C \rightarrow \mathbb{P}^1$ be a degree $k$ genus $g$ cover. The stratification of line bundles $L \in \mathrm{Pic}^d(C)$ by the splitting type of $f_*L$ is a refinement of the stratification by Brill-Noether loci $W^r_d(C)$. We prove that for general degree $k$ covers, these strata are smooth of the expected dimension. In particular, this determines the dimensions of all irreducible components of $W^r_d(C)$ for a general $k$-gonal curve (there are often components of different dimensions), extending results of Pflueger and Jensen-Ranganathan. The results here apply over any algebraically closed field.