Miracle-dz/UniFAR-FTUs huggingface dataset:
On the Structure of the Magnetic Field in a Kinematic ABC Flow Dynamo

The kinematic induction equation of MHD is solved numerically in the case of the normal "111" ABC flow using a general staggered mesh method. Careful 3-D visualizations of the topology of the magnetic field reveal that previous conclusions about the modes of operation of this type of kinematic dynamo must be revised. The two known windows of dynamo action at low and high magnetic Reynolds number, correspond to two distinct modes, both relying crucially on the replenishing of the magnetic field near a discontinuity at the β type stagnation points in the flow. One of these modes display double magnetic structures that were previously found only to obscure the physics of the dynamo: They turn out, however, to play an important part in the process of amplifying the magnetic field. Invariant properties of the mode in the second magnetic Reynolds number window support the case for the normal ABC flow as a fast dynamo.
Radio Constraints on the Identifications and Redshifts of Submillimeter Galaxies

We present radio maps from the Very Large Array (VLA) for 16 sources detected in a submillimeter (submm) survey of the distant universe. Our deep VLA 1.4 GHz maps allow us to identify radio counterparts or place stringent limits (≲20 μJy in the source plane) on the radio flux of the submm sources. We compare the spectral indices of our sources between 850 μm and 1.4 GHz to empirical and theoretical models for distant starburst galaxies and active galactic nuclei (AGNs) as a function of redshift. In this way we can derive redshift limits for the submm sources, even in the absence of an optical or near-infrared counterpart. We conclude that the submm population brighter than ~1 mJy has a median redshift of at least ~ 2, more probably ~ 2.5-3, with almost all galaxies at z ≫ 1. This estimate is a strong lower limit as both misidentification of the radio counterparts and nonthermal emission from an AGN will bias our redshift estimates to lower values. The high median redshift means that the submm population, if predominately powered by starbursts, contributes a substantial fraction of the total star formation density at high redshifts. A comparison of the spectral index limits with spectroscopic redshifts for proposed optical counterparts to individual submm galaxies suggests that half of the submm sources remain unidentified and thus their counterparts must be fainter than I ≳ 24.
The integrated Sachs–Wolfe effect in the AvERA cosmology

The recent AvERA cosmological simulation of R\'acz et al. (2017) has a $\Lambda \mathrm{CDM}$-like expansion history and removes the tension between local and Planck (cosmic microwave background) Hubble constants. We contrast the AvERA prediction of the integrated Sachs--Wolfe (ISW) effect with that of $\Lambda \mathrm{CDM}$. The linear ISW effect is proportional to the derivative of the growth function, thus it is sensitive to small differences in the expansion histories of the respective models. We create simulated ISW maps tracing the path of light-rays through the Millennium XXL cosmological simulation, and perform theoretical calculations of the ISW power spectrum. AvERA predicts a significantly higher ISW effect than $\Lambda \mathrm{CDM}$, $A=1.93-5.29$ times larger depending on the $l$ index of the spherical power spectrum, which could be utilized to definitively differentiate the models. We also show that AvERA predicts an opposite-sign ISW effect in the redshift range $z \approx 1.5 - 4.4$, in clear contrast with $\Lambda \mathrm{CDM}$. Finally, we compare our ISW predictions with previous observations. While at present these cannot distinguish between the two models due to large error bars, and lack of internal consistency suggesting systematics, ISW probes from future surveys will tightly constrain the models.
Spectrum Analysis of the Type Ib Supernova SN 1999dn: Probable Identifications of C II and Hα

Low-resolution spectra of SN 1999dn at early times are presented and compared with synthetic spectra generated with the parameterized supernova synthetic spectrum code SYNOW. We find that the spectra of SN 1999dn strongly resemble those of SN 1997X and SN 1984L, and hence we classify it as a Type Ib event. Line identifications are established through spectrum synthesis. Strong evidence of both Hα and C II λ6580 is found. We infer that Hα appears first, before the time of maximum brightness, and then is blended with and finally overwhelmed by the C II line after maximum; this favors a thin high-velocity hydrogen skin in this Type Ib supernova.
A Possible Third Component in the L Dwarf Binary System DENIS-P J020529.0−115925 Discovered with the Hubble Space Telescope

We present results showing that the multiple system DENIS-P J020529.0-115925 is likely to be a triple system of very low mass stars and brown dwarfs. The secondary of this previously known binary system shows a clear elongation on six images obtained at six different epochs. Significant residuals remain after point-spread function (PSF) subtraction on these images, which is characteristic of multiplicity and indicates that the secondary is probably a double itself. Dual-PSF fitting shows that the shape of the secondary is consistent with that of a binary system. These measurements show that the probability that DENIS-P J020529.0-115925 is a triple system is very high. The photometric and spectroscopic properties of the system are consistent with the presence of three components, with spectral types L5, L8, and T0.
The dwarf galaxy population of the Coma cluster to M_R=-11

We present the luminosity function and measurements of the scalelengths, colours, and radial distribution of dwarf galaxies in the Coma cluster down to R = 24. Our survey area is 674 arcmin 2 ; this is the deepest and most detailed survey covering such a large area. Our measurements agree with those of most previous authors at bright and intermediate magnitudes. The new results are: 1) Galaxies in the Coma cluster have a luminosity function φ ( L ) ∝ L α that is steep ( α ∼ − 1 . 7) for − 15 < M R < − 11, and is shallower brighter than this. The curvature in the luminosity function at M R ∼ − 15 is statistically signiﬁcant. 2) The galaxies that contribute most strongly to the luminosity function at − 14 < M R < − 12 have colours and scalelengths that are consistent with those of local dwarf spheroidal galaxies placed at the distance of Coma. 3) These galaxies with − 14 < M R < − 12 have a colour distribution that is very strongly peaked at B − R = 1 . 3. This is suggestive of a substantial degree of homogeneity in their star formation histories and metallicities. 4) These galaxies with − 14 < M R < − 12 also appear to be more conﬁned to the cluster core ( r ∼ 200 kpc) than the brighter galaxies. Alternatively, this observation may be explained in part or whole by the presence of an anomalously high number of background galaxies behind the cluster core. Velocity measurements of these galaxies would distinguish between these two possibilities.
The mass and momentum outflow rates of photoionized galactic outflows

Galactic outflows are believed to play an important role in regulating star formation in galaxies, but estimates of the outflowing mass and momentum have historically been based on uncertain assumptions. Here, we measure the mass, momentum, and energy outflow rates of seven nearby star-forming galaxies using ultraviolet absorption lines and observationally motivated estimates for the density, metallicity, and radius of the outflow. Low-mass galaxies generate outflows faster than their escape velocities with mass outflow rates up to twenty times larger than their star formation rates. These outflows from low-mass galaxies also have momenta larger than provided from supernovae alone, indicating that multiple momentum sources drive these outflows. Only 1-20\% of the supernovae energy is converted into kinetic energy, and this fraction decreases with increasing stellar mass such that low-mass galaxies drive more efficient outflows. We find scaling relations between the outflows and the stellar mass of their host galaxies (M$_\ast$) at the 2-3$\sigma$ significance level. The mass-loading factor, or the mass outflow rate divided by the star formation rate, scales as M$_\ast^{-0.4}$ and with the circular velocity as v$_\mathrm{circ}^{-1.6}$. The scaling of the mass-loading factor is similar to recent simulations, but the observations are a factor of five smaller, possibly indicating that there is a substantial amount of unprobed gas in a different ionization phase. The outflow momenta are consistent with a model where star formation drives the outflow while gravity counteracts this acceleration.
Entanglement in a fermion chain under continuous monitoring

We study the entanglement entropy of the quantum trajectories of a free fermion chain under continuous monitoring of local occupation numbers. We propose a simple theory for entanglement entropy evolution from disentangled and highly excited initial states. It is based on generalized hydrodynamics and the quasi-particle pair approach to entanglement in integrable systems. We test several quantitative predictions of the theory against extensive numerics and find good agreement. In particular, the volume law entanglement is destroyed by the presence of arbitrarily weak measurement.
Molecular Hydrogen in the Direction of ζ Orionis A

A spectrum of ζ Ori A over the wavelength interval 950-1150 Å recorded by the Interstellar Medium Absorption Profile Spectrograph (IMAPS) on the ORFEUS-SPAS I mission shows Lyman and Werner band absorption features from molecular hydrogen in rotational levels J = 0, 1, 2, 3, and 5. Most of the molecules are found in two distinct velocity components. One is at a heliocentric radial velocity of about -1 km s-1 with log N(H2) = 14.5 and a rotational temperature Trot = 950 K, while the other is at +25 km s-1 with log N(H2) = 15.9 and Trot = 320 K. Some extra H2 exists in a much weaker component [log N(H2) = 14.0] between the two main peaks. The H2 component at -1 km s-1 exhibits profile shapes that become broader and show small displacements toward more negative velocities as J increases. These changes are inconsistent with a simple interpretation that UV optical pumping in an optically thin, uniform medium creates the H2 in excited rotational levels. Differential shielding of the UV radiation at certain velocities does not appear to be a satisfactory explanation for the effect. Evidence from atomic features at other velocities may offer some insight into the origin of this unusual behavior exhibited by the H2 profiles. Absorption features from moderately ionized atoms at -94 km s-1 and more highly ionized species at about -36 km s-1 suggest that along the line of sight to ζ Ori A, there may be a standing bow shock with an initial compression ratio of 2.6. This shock is probably created when a negative-velocity gas flow collides with an obstruction, in this case a neutral cloud at 0 km s-1. If this interpretation is correct, the H2 with the changing profiles may represent molecules forming in the postshock gas that is undergoing further compression as it recombines and cools. We suggest that molecules can form initially by associative detachment of H- in a moving, warm, partly ionized medium behind the front. The H2 in this area is most conspicuous in the higher J levels. Later, when the gas becomes very cool, neutral, and more compressed as it comes nearly to a halt, it is more easily seen in the lowest J levels. In this part of the medium, the principal way of producing H2 should be from reactions on the surfaces of dust grains, as one expects for quiescent interstellar clouds.
Ultradiscrete two-variable Oregonator

Ultradiscretization is a limiting procedure transforming a given differential/difference equation into a ultradiscrete equation. Ultradiscrete equations are expressed by addition, subtraction and/or max. The procedure is expected to preserve the essential properties of the original equations. As a method of ultradiscretization, there is "tropical discretization" proposed by M. Murata. In this paper, we shall modify it, and derive a ultradiscrete equation from the continuous model of the BZ reaction. The derived equation generates a cellular automaton by restricting the values of the parameters, which is equivalent to one of those introduced by D. Takahashi, A. Shida, and M. Usami. By setting appropriate initial values, we can obtain the typical patterns of the BZ reaction. Furthermore, we consider the equation without diffusion effect and derive the explicit solutions. As a result, the solutions corresponding to the limit cycle (oscillation) appearing in the continuous model will be found.
ROSAT, ASCA, and OSSE Observations of the Broad-Line Radio Galaxy 3C 120

We present simultaneous observations of the superluminal radio galaxy 3C 120 performed with the ASCA and GRO (OSSE) satellites in 1994 February-March, as well as an analysis of all the ROSAT archival data. The ASCA spectrum of this object can be described by an absorbed (NH = 1.6 × 1021 cm-2) power law with a photon index of ΓASCA = 2 and a very broad (σ > 0.8 keV) intense iron line (EW > 400 eV) at ~6 keV. The combined ASCA-OSSE data do not exclude the presence of a narrower (σ = 0.4 keV) and less intense (EW < 300 eV) iron line plus a hard component, corresponding either to reflection from an accretion disk or to a flatter power law from a jet. However, a single power law plus broad Fe line is preferred from a statistical point of view by the ASCA data. The ROSAT data yield a column density in excess of the Galactic value. The spectral slopes, ranging from ΓROSAT = 2.5 to 3.3, are steeper than that measured by ASCA, suggesting the presence of a soft excess. The 0.1-2 keV power-law slope is variable and softer at higher intensity. These results show that the combined soft and hard X-ray spectrum of 3C 120 is rather complex. The intrinsic absorption, the soft excess, and the iron line indicate that the X-ray emission from this blazar-like radio galaxy is dominated by a Seyfert-like component, at least in the 0.1-10 keV energy band. The jet contribution, if present, becomes important only at higher energies.
Multiple Myeloma: Modification and Adaptation of Plasma Cell Morphology Algorithm for the Prognosis of Congolese Patient

Objectives: To determine the multiple myeloma (MM) prognostic formulas applicable in Congolese with many aberrant and/or immature plasma cells according to GOASGUEN’s plasma cell morphology algorithm (PMA). Methods: The prospective, observational and descriptive study was carried out at the Ngaliema Clinic in Kinshasa from July 2016 to December 2019. The va-riables studied were the plasma cell types and the prognosis groups according to GOASGUEN and ZANDECKI. The nucleolus, the chromatin and the N/C ratio of 2 for each plasma cell encountered in multiple myeloma are examined in order by asking three successive questions as follows: 1) Is the nucleolus present? If yes, we denote 1; if not, note 0; 2) Is the chromatin thin? If yes, we score 1; if not we score 0; 3) The N/C sive nature of MM in Congolese Blacks.
Asymptotic adaptive threshold for connectivity in a random geometric social network.

Consider a dynamic random geometric social network identified by $s_t$ independent points $x_t^1,\ldots,x_t^{s_t}$ in the unit square $[0,1]^2$ that interact in continuous time $t\geq 0$. The generative model of the random points is a Poisson point measures. Each point $x_t^i$ can be active or not in the network with a Bernoulli probability $p$. Each pair being connected by affinity thanks to a step connection function if the interpoint distance $\|x_t^i-x_t^j\|\leq a_\mathsf{f}^\star$ for any $i\neq j$. We prove that when $a_\mathsf{f}^\star=\sqrt{\frac{(s_t)^{l-1}}{p\pi}}$ for $l\in(0,1)$, the number of isolated points is governed by a Poisson approximation as $s_t\to\infty$. This offers a natural threshold for the construction of a $a_\mathsf{f}^\star$-neighborhood procedure tailored to the dynamic clustering of the network adaptively from the data.
Juvenile fish in Cystoseira forests: influence of habitat complexity and depth fish behaviour

The sublittoral forests formed by the fucoid algae Cystoseira spp. are important juvenile habitats for many Mediterranean fish species. However, the spatial variability of juvenile fish assemblages within the forests and the potential environmental drivers, such as depth and habitat complexity, remain poorly understood. We estimated the density, size and behaviour of juvenile fish assemblages in subtidal (0-15 meters depth) Cystoseira brachycarpa var. balearica forests in north Minorca Island (North-west-ern Mediterranean Sea) over two consecutive autumns (2012 and 2013). Depth and forest complexity, here measured as canopy volume, had both a significant and independent effect on the juvenile fish assemblages in terms of species abundance composition and body size. Assemblages found in the shallowest depth range (3-4m) were characterized by greater density of the ornate wrasse Thalassoma pavo, while those deeper down (10-12m) had higher density of the rainbow wrasse Coris julis , independently of its size composition. Juveniles of both species were more abundant in less complex forests; conversely, juveniles of wrasse of the genus Symphodus were more abundant in more complex forests. The smallest sizes of T. pavo occurred in the most complex forests. On the other hand, our results demonstrated that juvenile fish behaviour was unrelated to the complexity of the Cystoseira forests, but mainly related to the body length. The effects of body length on behaviour were however species-dependent. Cryptic and transitory behaviour was mostly observed in the smallest and largest juveniles of T. pavo and C. julis , respectively, while the behaviour of Symphodus spp. was unrelated to their body length. Our study highlights the importance of preserving healthy Cystoseira forests and their intrinsically patchy nature, as this habitat, with its mosaic of different degrees of complexity and bathymetric variability, enable the presence of different fish species at various life stages. and structural variability.
An accurate calculation of the nucleon axial charge with lattice QCD

Author(s): Berkowitz, Evan; Brantley, David; Bouchard, Chris; Chang, Chia Cheng; Clark, MA; Garron, Nicholas; Joo, Balint; Kurth, Thorsten; Monahan, Chris; Monge-Camacho, Henry; Nicholson, Amy; Orginos, Kostas; Rinaldi, Enrico; Vranas, Pavlos; Walker-Loud, Andre | Abstract: We report on a lattice QCD calculation of the nucleon axial charge, $g_A$, using M quot;{o}bius Domain-Wall fermions solved on the dynamical $N_f=2+1+1$ HISQ ensembles after they are smeared using the gradient-flow algorithm. The calculation is performed with three pion masses, $m_\pi\sim\{310,220,130\}$ MeV. Three lattice spacings ($a\sim\{0.15,0.12,0.09\}$ fm) are used with the heaviest pion mass, while the coarsest two spacings are used on the middle pion mass and only the coarsest spacing is used with the near physical pion mass. On the $m_\pi\sim220$ MeV, $a\sim0.12$ fm point, a dedicated volume study is performed with $m_\pi L \sim \{3.22,4.29,5.36\}$. Using a new strategy motivated by the Feynman-Hellmann Theorem, we achieve a precise determination of $g_A$ with relatively low statistics, and demonstrable control over the excited state, continuum, infinite volume and chiral extrapolation systematic uncertainties, the latter of which remains the dominant uncertainty. Our final determination at 2.6\% total uncertainty is $g_A = 1.278(21)(26)$, with the first uncertainty including statistical and systematic uncertainties from fitting and the second including model selection systematics related to the chiral and continuum extrapolation. The largest reduction of the second uncertainty will come from a greater number of pion mass points as well as more precise lattice QCD results near the physical pion mass.
Light Elements in Main Sequence Stars: Li, Be, B, C, O

The abundances of the {\it rare} light elements, Li, Be, and B, provide clues about stellar structure and evolution, about Galactic evolution and about their nucleosynthesis, including production during the Big Bang. The abundances of the {\it abundant} light elements, C and O, reveal information about the chemical history of the Galaxy and the mass spectrum of early generations of stars.
Controlling for Lexical Closeness in Survey Research: A Controlling for Lexical Closeness in Survey Research: A Demonstration on the Technology Acceptance Model Demonstration on the Technology Acceptance Model

: Word co-occurrences in text carry lexical information that can be harvested by data-mining tools such as latent semantic analysis (LSA). In this research perspective paper, we demonstrate the potency of using such embedded information by demonstrating that the technology acceptance model (TAM) can be reconstructed significantly by analyzing unrelated newspaper articles. We suggest that part of the reason for the phenomenal statistical validity of TAM across contexts may be related to the lexical closeness among the keywords in its measurement items. We do so not to critique TAM but to praise the quality of its methodology. Next, putting that LSA reconstruction of TAM into perspective, we show that empirical data can provide a significantly better fitting model than LSA data can. Combined, the results raise the possibility that a significant portion of variance in survey based research results from word co-occurrences in the language itself regardless of the theory or context of the study. Addressing this possibility, we suggest a method to statistically control for lexical closeness.
Measuring the Angular Correlation Function for Faint Galaxies in High Galactic Latitude Fields

A photometric survey of faint galaxies in three high Galactic latitude fields (each ~49 arcmin2) with subarcsecond seeing is used to study the clustering properties of the faint galaxy population. Multicolor photometry of the galaxies has been obtained to magnitude limits of V~ 25, R ~ 25, and I ~ 24. Angular correlation analysis is applied to magnitude-limited and color-selected samples of galaxies from the three fields for angular separations ranging from 10'' to 126''. General agreement is obtained with other recent studies, which show that the amplitude of the angular correlation function, ω(θ), is smoothly decreasing as a function of limiting magnitude. The observed decline of ω(θ) rules out the viability of "maximal merger" galaxy evolution models. Using redshift distributions extrapolated to faint magnitude limits, models of galaxy clustering evolution are calculated and compared to the observed I band ω(θ). Faint galaxies are determined to have correlation lengths and clustering evolution parameters of either r0 ~ 4 h-1 Mpc and ϵ ~ 0-1; r0 ~ 5-6 h-1 Mpc and ϵ > 1; or r0 ~ 2-3 h-1 Mpc and ϵ ~ -1.2, assuming q0 = 0.5 and with h = H0/100 km s-1 Mpc-1. The latter case is for clustering fixed in comoving coordinates and is probably unrealistic since most local galaxies are observed to be more strongly clustered. Even though the first of the three cases has the most reasonable rate of clustering evolution, distinguishing the correct r0 for the faint galaxies is not possible with the current data. No significant variations in the clustering amplitude as a function of color are detected, for all the color-selected galaxy samples considered. The validity of this result is discussed in relation to other determinations of ω(θ) for galaxies selected by color.