Miracle-dz/UniFAR-FTUs huggingface dataset:
Continuum and line modelling of discs around young stars : II. Line diagnostics for GASPS from the DENT grid

Aims. We want to understand the chemistry and physics of disks on the basis of a large unbiased and statistically relevant grid o f disk models. One of the main goals is to explore the diagnostic power of various gas emission lines and line ratios for deriving main disk parameters such as the gas mass. Methods. We explore the results of the DENT grid (Disk Evolution with Neat Theory) that consists of 300 000 disk models with 11 free parameters. Through a statistical analysis, we search for correlations and trends in an effort to find tools for disk diagnostic. Results. All calculated quantities like species masses, temperatur es, continuum and line fluxes di ffer by several orders of magnitude across the entire parameter space. The broad distribution of these quantities as a function of input parameters shows the limitation of using a prototype T Tauri or Herbig Ae/Be disk model. The statistical analysis of the DENT grid shows that CO gas is rarely the dominant carbon reservoir in disks. Models with large inner radii (10 times the dust condensation radius) and/or shallow surface density gradients lack massive gas phase water reservoirs. Also, 60% of the disks have gas temperatures averaged over the oxygen mass in the range between 15 and 70 K; the average gas temperatures for CO and O differ by less than a factor two. Studying the observational diagnostics, the [Cii] 158µm fine structure line flux is very sensitive to the stellar UV flu x and presence of a UV excess and it traces the outer disk radius (Rout). In the submm, the CO low J rotational lines also trace Rout. Low [Oi] 63/145 line ratios (< a few) can be explained with cool atomic O gas in the uppermost surface layers leading to self-absorption in the 63 µm line; this occurs mostly for massive non-flaring, settled disk models w ithout UV excess. A combination of the [Oi] 63 line and low J CO lines correlates with several disk properties such as the average Oi gas temperature in disks, the outer disk radius, and the UV excess. Conclusions. The [Oi] 63/CO 2-1 line ratio is a powerful diagnostic to break disk modeling degeneracies. A combination of the [Oi] 63µm flux and the [Oi] 63/CO 2-1 line ratio can be used for Mgas≤ 10 −3 M⊙ to obtain an order of magnitude estimate for the disk gas mass purely from gas observations. The previously used conversion of a CO submm line flux alone generally leads to larger uncertainties.
Kármán vortex shedding in the wake of a 2D hydrofoil: Measurement and numerical simulation

The present study deals with the shedding process of the Karman vortices at the trailing edge of a 2D hydrofoil at high Reynolds numbers. Investigations are performed in order to evaluate the ability of an unsteady numerical simulation to accurately reproduce the vortex shedding frequency. The vortex shedding frequency, derived from flow induced vibrations measurements, is found to follow the Strouhal law as long as none of the resonance frequencies of the hydrofoil is excited. For such lock-off conditions, the Karman vortices exhibit a strong spanwise 3D instability. For Reynolds numbers ranging from 35’000 to 40’000, the torsion mode of the hydrofoil is excited with a substantial increase of the vibration level. In this case, the shedding frequency is locked onto the vibration frequency. The vortex roll-up, shedding and advection are well predicted by the computations as well as the 3D instability. Nevertheless, the numerical simulations underestimate the vortex shedding frequency of about 20%. No significant influence of the turbulence models, the incoming flow turbulence intensity and the mesh size is observed on the computed values. To investigate the issue of discrepancy between absolute values of measured and computed shedding frequency, we intend to address the sensitivity of the vortex shedding frequency to the boundary layer. It is indeed know that the boundary layer transition point to turbulence for this profile geometry is located slightly downstream of the midchord for an incidence angle of 0°. In contrast, the numerical simulation, as it solves the RANS equations, models the whole flow as being turbulent. Consequently, rough stripes are placed just behind the hydrofoil leading edge. For such a configuration, the boundary layer is turbulent from the leading edge in a similar way to the computations. Notable influence of the roughness is observed: The vortex shedding frequencies are significantly decreased in comparison to the smooth leading edge. The average Strouhal number St decreases from 0.24 to 0.18 and is nearly equal to the computational one, St=0.19. Karman vortices being very sensitive to the boundary layer, differences in the transition points between experiments and computations have to be minimized in order to aspire good agreement.
Characterizing Earth-like Planets Using a Combination of High-Dispersion Spectroscopy and High-Contrast Instruments: Doppler-shifted Water and Oxygen Lines

Future radial velocity, astrometric, and direct-imaging surveys will find nearby Earth-sized planets within the habitable zone in the near future. How can we search for water and oxygen in those nontransiting planets? We show that a combination of high-dispersion spectroscopic and coronagraphic techniques is a promising technique to detect molecular lines imprinted in the scattered light of Earth-like planets (ELPs). In this method, the planetary signals are spectroscopically separated from telluric absorption by using the Doppler shift. Assuming a long observing campaign (a 10-day exposure) using a high-dispersion spectrometer (R=50,000) with speckle suppression on a 30-m telescope, we simulate the spectra from ELPs around M dwarfs (whose stellar effective temperature is 2750-3750 K) at 5 pc. Performing a cross-correlation analysis with the spectral template of the molecular lines, we find that raw contrasts of $10^{-4}$ and $10^{-5}$ (using Y, J, and H bands) are required to detect water vapor at the 3 $\sigma$ and 16 $\sigma$ levels, respectively, for $T_\star$=3000 K. The raw contrast of $10^{-5}$ is required for a 6 $\sigma$ detection of the oxygen 1.27 $\mu$m band. We also examine possible systematics, incomplete speckle subtraction, and the correction for telluric lines. When those are not perfect, a telluric water signal appears in the cross-correlation function. However, we find the planetary signal is separated from that resulting from the velocity difference. We also find that the intrinsic water lines in the Phoenix spectra are too weak to affect the results for water detection. We conclude that a combination of high-dispersion spectroscopy and high-contrast instruments can be a powerful means to characterize ELPs in the extremely large telescope era.
TRACING RECENT STAR FORMATION OF RED EARLY-TYPE GALAXIES OUT TO z ∼ 1

We study the mid-infrared (IR) excess emission of early-type galaxies (ETGs) on the red sequence at z < 1 using a spectroscopic sample of galaxies in the fields of Great Observatories Origins Deep Survey (GOODS). In the mass-limited sample of 1025 galaxies with Mstar > 1010.5 M☉ and 0.4 < z < 1.05, we identify 696 Spitzer 24 μm detected (above the 5σ) galaxies and find them to have a wide range of NUV-r and r-[12 μm] colors despite their red optical u − r colors. Even in the sample of very massive ETGs on the red sequence with Mstar > 1011.2 M☉, more than 18% show excess emission over the photospheric emission in the mid-IR. The combination with the results of red ETGs in the local universe suggests that the recent star formation is not rare among quiescent, red ETGs at least out to z ∼ 1 if the mid-IR excess emission results from intermediate-age stars or/and from low-level ongoing star formation. Our color–color diagram including near-UV and mid-IR emissions are efficient not only for identifying ETGs with recent star formation, but also for distinguishing quiescent galaxies from dusty star-forming galaxies.
Novel Concept of Non-Debye Dipole Relaxation Processes for the Interpretation of Physical Origin of Dielectric Loss in the Glass Formers, Drugs, Polymers and Plastic Crystals

The physical origin of dielectric loss is shown to be sum of n number of subunits relaxation of a molecule, where n=1,2,3. For each subunit relaxation, the idea of intermolecular dipole-dipole interactions triggered non-Debye dipole, ($\bf G$)$_{n}$=((1-g$_d$)$\bf G$$_{0}$)$_{n}$, and the ensuing dual dipole ($\bf G$$_{\pm}$)$_n$=($\bf G$$_0$$\pm$$\bf G$)$_n$, relaxation processes is proposed, where $\bf G$$_{-}$=g$_{d}$$\bf G$$_{0}$, $\bf G$$_{+}$=(2-g$_{d}$)$\bf G$$_{0}$, and $\bf G$$_{0}$ is a Debye dipole. Each subunit motion is statistically highly independent process and discriminated by Debye and non-Debye relaxation (NDR) time, where g$_d$ is an exponent 0<g$_d$<1 and signifies interaction strength with a redistribution and conservation of Debye dielectric loss energy. The proposed concept provides a new insight for the NDR and discloses the physical origin of $\alpha$, $\beta$, $\gamma$, $\delta$ relaxations and excess wing of glass formers, plastic crystals, drugs, etc., with an excellent agreement with experimental results.
Z-dark search with the ATLAS detector

The search of the“hidden sector” via new neutral light bosons Z-dark (Zd) could be revealed by the study of the decay of the discovered Higgs-like boson or any other undiscovered Higgs boson. After the LHC concluded a successful first period of running, The ATLAS Collaboration published its latest results on the H → ZdZd → 4l analysis using up to 20 fb-1 of integrated luminosity at √s = 8 TeV. In this proceeding I present a summary of the recent results on the search of the Zd in the signature H → ZdZd → 4l with the ATLAS detector at the LHC.
Multi-band morpho-Spectral Component Analysis Deblending Tool (MuSCADeT): Deblending colourful objects

We introduce a new algorithm for colour separation and deblending of multi-band astronomical images called MuSCADeT which is based on Morpho-spectral Component Analysis of multi-band images. The MuSCADeT algorithm takes advantage of the sparsity of astronomical objects in morphological dictionaries such as wavelets and their differences in spectral energy distribution (SED) across multi-band observations. This allows us to devise a model independent and automated approach to separate objects with different colours. We show with simulations that we are able to separate highly blended objects and that our algorithm is robust against SED variations of objects across the field of view. To confront our algorithm with real data, we use HST images of the strong lensing galaxy cluster MACS J1149+2223 and we show that MuSCADeT performs better than traditional profile-fitting techniques in deblending the foreground lensing galaxies from background lensed galaxies. Although the main driver for our work is the deblending of strong gravitational lenses, our method is fit to be used for any purpose related to deblending of objects in astronomical images. An example of such an application is the separation of the red and blue stellar populations of a spiral galaxy in the galaxy cluster Abell 2744. We provide a python package along with all simulations and routines used in this paper to contribute to reproducible research efforts. Codes can be found at this http URL
Mitigating barren plateaus with transfer-learning-inspired parameter initializations

Variational quantum algorithms (VQAs) are widely applied in the noisy intermediate-scale quantum era and are expected to demonstrate quantum advantage. However, training VQAs faces difficulties, one of which is the so-called barren plateaus (BPs) phenomenon, where gradients of cost functions vanish exponentially with the number of qubits. In this paper, inspired by transfer learning, where knowledge of pre-solved tasks could be further used in a different but related work with training efficiency improved, we report a parameter initialization method to mitigate BP. In the method, a small-sized task is solved with a VQA. Then the ansatz and its optimum parameters are transferred to tasks with larger sizes. Numerical simulations show that this method could mitigate BP and improve training efficiency. A brief discussion on how this method can work well is also provided. This work provides a reference for mitigating BP, and therefore, VQAs could be applied to more practical problems.
Spin-wave spectra in antidot lattice with inhomogeneous perpendicular magnetic anisotropy

Magnonic crystals are structures with periodically varied magnetic properties that are used to control collective spin-wave excitations. With micromagnetic simulations, we study spin-wave spectra in a 2D antidot lattice based on a multilayered thin film with perpendicular magnetic anisotropy (PMA). We show that the modification of the PMA near the antidot edges introduces interesting changes to the spin-wave spectra, even in a fully saturated state. In particular, the spectra split into two types of excitations: bulk modes with amplitude concentrated in a homogeneous part of the antidot lattice and edge modes with an amplitude localized in the rims of reduced PMA at the antidot edges. Their dependence on the geometrical or material parameters is distinct, but at resonance conditions fulfilled, we found strong hybridization between bulk and radial edge modes. Interestingly, the hybridization between the fundamental modes in bulk and rim is of magnetostatic origin, but the exchange interactions determine the coupling between higher-order radial rim modes and the fundamental bulk mode of the antidot lattice.
Chameleon Cache: Approximating Fully Associative Caches with Random Replacement to Prevent Contention-Based Cache Attacks

Randomized, skewed caches (RSCs) such as CEASER-S have recently received much attention to defend against contention-based cache side channels. By randomizing and regularly changing the mapping(s) of addresses to cache sets, these techniques are designed to obfuscate the leakage of memory access patterns. However, new attack techniques, e.g., Prime+Prune+Probe, soon demonstrated the limits of RSCs as they allow attackers to more quickly learn which addresses contend in the cache and use this information to circumvent the randomization. To yet maintain side-channel resilience, RSCs must change the random mapping(s) more frequently with adverse effects on performance and implementation complexity.This work aims to make randomization-based approaches more robust to allow for reduced re-keying rates and presents Chameleon Cache. Chameleon Cache extends RSCs with a victim cache (VC) to decouple contention in the RSC from evictions observed by the user. The VC allows Chameleon Cache to make additional use of the multiple mappings RSCs provide to translate addresses to cache set indices: when a cache line is evicted from the RSC to the VC under one of its mappings, the VC automatically reinserts this evicted line back into the RSC by using a different mapping. As a result, the effects of previous RSC set contention are hidden and Chameleon Cache exhibits side-channel resistance and eviction patterns similar to fully associative caches with random replacement. We show that Chameleon Cache has performance overheads of < 1% and stress that VCs are more generically helpful to increase side-channel resistance and re-keying intervals of randomized caches.
Category-Level Global Camera Pose Estimation with Multi-Hypothesis Point Cloud Correspondences

Correspondence search is an essential step in rigid point cloud registration algorithms. Most methods maintain a single correspondence at each step and gradually remove wrong correspondances. However, building one-to-one correspondence with hard assignments is extremely difficult, especially when matching two point clouds with many locally similar features. This paper proposes an optimization method that retains all possible correspondences for each keypoint when matching a partial point cloud to a complete point cloud. These uncertain correspondences are then gradually updated with the estimated rigid transformation by considering the matching cost. More-over, we propose a new point feature descriptor that measures the similarity between local point cloud regions. Extensive experiments show that our method outperforms the state-of-the-art (SoTA) methods even when matching different objects within the same category. Notably, our method outperforms the SoTA methods when registering real-world noisy depth images to a template shape by up to 20% performance.
Callipepla: Stream Centric Instruction Set and Mixed Precision for Accelerating Conjugate Gradient Solver

The continued growth in the processing power of FPGAs coupled with high bandwidth memories (HBM), makes systems like the Xilinx U280 credible platforms for linear solvers which often dominate the run time of scientific and engineering applications. In this paper, we present Callipepla, an accelerator for a preconditioned conjugate gradient linear solver (CG). FPGA acceleration of CG faces three challenges: (1) how to support an arbitrary problem and terminate acceleration processing on the fly, (2) how to coordinate long-vector data flow among processing modules, and (3) how to save off-chip memory bandwidth and maintain double (FP64) precision accuracy. To tackle the three challenges, we present (1) a stream-centric instruction set for efficient streaming processing and control, (2) vector streaming reuse (VSR) and decentralized vector flow scheduling to coordinate vector data flow among modules and further reduce off-chip memory access latency with a double memory channel design, and (3) a mixed precision scheme to save bandwidth yet still achieve effective double precision quality solutions. To the best of our knowledge, this is the first work to introduce the concept of VSR for data reusing between on-chip modules to reduce unnecessary off-chip accesses and enable modules working in parallel for FPGA accelerators. We prototype the accelerator on a Xilinx U280 HBM FPGA. Our evaluation shows that compared to the Xilinx HPC product, the XcgSolver, Callipepla achieves a speedup of 3.94x, 3.36x higher throughput, and 2.94x better energy efficiency. Compared to an NVIDIA A100 GPU which has 4x the memory bandwidth of Callipepla, we still achieve 77% of its throughput with 3.34x higher energy efficiency. The code is available at https://github.com/UCLA-VAST/Callipepla.
ON THE CARBON-TO-OXYGEN RATIO MEASUREMENT IN NEARBY SUN-LIKE STARS: IMPLICATIONS FOR PLANET FORMATION AND THE DETERMINATION OF STELLAR ABUNDANCES

Recent high-resolution spectroscopic analysis of nearby FGK stars suggests that a high C/O ratio of greater than 0.8, or even 1.0, is relatively common. Two published catalogs find C/O > 0.8 in 25%–30% of systems, and C/O > 1.0 in ∼6%–10%. It has been suggested that in protoplanetary disks with C/O > 0.8 that the condensation pathways to refractory solids will differ from what occurred in our solar system, where C/O = 0.55. The carbon-rich disks are calculated to make carbon-dominated rocky planets, rather than oxygen-dominated ones. Here we suggest that the derived stellar C/O ratios are overestimated. One constraint on the frequency of high C/O is the relative paucity of carbon dwarf stars (10−3–10−5) found in large samples of low-mass stars. We suggest reasons for this overestimation, including a high C/O ratio for the solar atmosphere model used for differential abundance analysis, the treatment of a Ni blend that affects the O abundance, and limitations of one-dimensional LTE stellar atmosphere models. Furthermore, from the estimated errors on the measured stellar C/O ratios, we find that the significance of the high C/O tail is weakened, with a true measured fraction of C/O > 0.8 in 10%–15% of stars, and C/O > 1.0 in 1%–5%, although these are still likely overestimates. We suggest that infrared T-dwarf spectra could show how common high C/O is in the stellar neighborhood, as the chemistry and spectra of such objects would differ compared to those with solar-like abundances. While possible at C/O > 0.8, we expect that carbon-dominated rocky planets are rarer than others have suggested.
COMPILING: A Benchmark Dataset for Chinese Complexity Controllable Definition Generation

“The definition generation task aims to generate a word’s definition within a specific context automatically. However, owing to the lack of datasets for different complexities, the definitions produced by models tend to keep the same complexity level. This paper proposes a novel task of generating definitions for a word with controllable complexity levels. Correspondingly, we introduce COMPILING, a dataset given detailed information about Chinese definitions, and each definition is labeled with its complexity levels. The COMPILING dataset includes 74,303 words and 106,882 definitions. To the best of our knowledge, it is the largest dataset of the Chinese definition generation task. We select various representative generation methods as baselines for this task and conduct evaluations, which illustrates that our dataset plays an outstanding role in assisting models in generating different complexity-level definitions. We believe that the COMPILING dataset will benefit further research in complexity controllable definition generation. ”
GPU-based Data-parallel Rendering of Large, Unstructured, and Non-convexly Partitioned Data

Computational fluid dynamic simulations often produce large clusters of finite elements with non-trivial, non-convex boundaries and uneven distributions among compute nodes, posing challenges to compositing during interactive volume rendering. Correct, in-place visualization of such clusters becomes difficult because viewing rays straddle domain boundaries across multiple compute nodes. We propose a GPU-based, scalable, memory-efficient direct volume visualization framework suitable for in~situ and post~hoc usage. Our approach reduces memory usage of the unstructured volume elements by leveraging an exclusive or-based index reduction scheme and provides fast ray-marching-based traversal without requiring large external data structures built over the elements themselves. Moreover, we present a GPU-optimized deep compositing scheme that allows correct order compositing of intermediate color values accumulated across different ranks that works even for non-convex clusters. Our method scales well on large data-parallel systems and achieves interactive frame rates during visualization. We can interactively render both Fun3D Small Mars Lander (14 GB / 798.4 million finite elements) and Huge Mars Lander (111.57 GB / 6.4 billion finite elements) data sets at 14 and 10 frames per second using 72 and 80 GPUs, respectively, on TACC's Frontera supercomputer.
Enumeration of max-pooling responses with generalized permutohedra

We investigate the combinatorics of max-pooling layers, which are functions that downsample input arrays by taking the maximum over shifted windows of input coordinates, and which are commonly used in convolutional neural networks. We obtain results on the number of linearity regions of these functions by equivalently counting the number of vertices of certain Minkowski sums of simplices. We characterize the faces of such polytopes and obtain generating functions and closed formulas for the number of vertices and facets in a 1D max-pooling layer depending on the size of the pooling windows and stride, and for the number of vertices in a special case of 2D max-pooling.
Introduction to minimum message length inference

The aim of this manuscript is to introduce the Bayesian minimum message length principle of inductive inference to a general statistical audience that may not be familiar with information theoretic statistics. We describe two key minimum message length inference approaches and demonstrate how the principle can be used to develop a new Bayesian alternative to the frequentist $t$-test as well as new approaches to hypothesis testing for the correlation coefficient. Lastly, we compare the minimum message length approach to the closely related minimum description length principle and discuss similarities and differences between both approaches to inference.