bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lithium in Kepler Red Giants: Defining Normal and Anomalous
Authors: Tayar Jamie , Carlberg Joleen K. , Aguilera-Gómez Claudia , Sayeed Maryum 
Published: July 2023

Abstract
The orders-of-magnitude variations in the lithium abundances of evolved stars have long been a puzzle. Diluted signals, ambiguous evolutionary states, and unknown masses have made it challenging to both map the expected lithium signals and explain the anomalously lithium-rich stars. Using a set of asteroseismically characterized evolved stars, we show here that the base lithium abundance in red giant stars is mass-dependent, with higher-mass stars having higher “normal” lithium abundances, while highly lithium-enhanced stars may cluster around 0.8 or 1.8 M
☉. We confirm previous studies that have shown that lithium enhancement and rapid rotation are often coincident but find that the actual correlation between lithium abundance and rotation rate, whether surface, internal, or radial differential rotation, is weak. Our data support previous assertions that most lithium-rich giants are in the core-helium-burning phase. We also note a tentative correlation between the highest lithium abundances and unusual carbon-to-nitrogen ratios, which is suggestive of binary interactions, though we find no simple correlation between lithium richness and indicators of binarity.
Application of the Disk Instability Model to All Quasiperiodic Eruptions
Authors: Pan Xin , Li Shuang-Liang , Cao Xinwu 
Published: July 2023

Abstract
After the first quasiperiodic eruption (QPE; GSN 069) was reported in 2019, four other sources have been identified as a QPE or a candidate. However, the physics behind QPEs is still unclear, although several models have been proposed. Pan et al. proposed an instability model for an accretion disk with magnetically driven outflows in the first QPE of GSN 069, which is able to reproduce both the light curve and the evolution of the spectra fairly well. In this work, we extend this model to all QPEs. We improve the calculations of the spectrum of the disk by introducing a hardening factor, which is caused by a deviation of opacity from a blackbody. We find that the light curves and evolution of the spectra of the four QPEs and candidates can all be well reproduced by our model calculations.
Understanding the Level of Turbulence by Asymmetric Distributions: A Motivation for Measurements in Space Plasmas
Authors: Gallo-Méndez Iván , Moya Pablo S. 
Published: July 2023

Abstract
In this article, on the basis of the Langevin equation applied to velocity fluctuations, we numerically model the partial variance of increments, which is a useful tool to measure time and spatial correlations in space plasmas. We consider a coupled map lattice model to relate the spatial scale of fluctuations, k, to some macro parameters of the systems, such as the Reynolds number, R

λ
, the κ parameter of Kappa distributions, and a skewness parameter, δ. To do so, we compute the velocity probability density function (pdf) for each spatial scale and different values of Reynolds number in the simulations. We fit the pdf with a Skew–Kappa distribution, and we obtain a numerical relationship between the level of turbulence of the plasma and the skewness of obtained distributions, namely,

〈
δ
〉
∼

R

λ

−
1

/

2

. We expect the results exposed in this paper to be useful as a tool to characterize the turbulence in the context of space plasma and other environments.
2 mm Observations and the Search for High-redshift Dusty Star-forming Galaxies
Authors: Cowie L. L. , Barger A. J. , Bauer F. E. 
Published: July 2023

Abstract
Finding high-redshift (z ≫ 4) dusty star-forming galaxies is extremely challenging. It has recently been suggested that millimeter selections may be the best approach since the negative K-correction makes galaxies at a given far-infrared luminosity brighter at z ≳ 4 than those at z = 2–3. Here we analyze this issue using a deep Atacama Large Millimeter/submillimeter Array (ALMA) 2 mm sample obtained by targeting ALMA 870 μm priors (these priors were the result of targeting SCUBA-2 850 μm sources) in the GOODS-S. We construct prior-based 2 mm galaxy number counts and compare them with published blank field-based 2 mm counts, finding good agreement down to 0.2 mJy. Only a fraction of the current 2 mm extragalactic background light is resolved, and we estimate what observational depths may be needed to resolve it fully. By complementing the 2 mm ALMA data with a deep SCUBA-2 450 μm sample, we exploit the steep gradient with a redshift of the 2 mm–450 μm flux density ratio to estimate redshifts for those galaxies without spectroscopic or robust optical/near-infrared photometric redshifts. Our observations measure galaxies with star formation rates in excess of 250 M
⊙ yr−1. For these galaxies, the star formation rate densities fall by a factor of 9 from z = 2–3 to z = 5–6.
Quantifying the Energy Budget in the Solar Wind from 13.3 to 100 Solar Radii
Authors: Halekas J. S. , Bale S. D. , Berthomier M. , Chandran B. D. G. , Drake J. F. , Kasper J. C. , Klein K. G. , Larson D. E. , Livi R. , Pulupa M. P. , Stevens M. L. , Verniero J. L. , Whittlesey P. 
Published: July 2023

Abstract
A variety of energy sources, ranging from dynamic processes, such as magnetic reconnection and waves, to quasi-steady terms, such as plasma pressure, may contribute to the acceleration of the solar wind. We utilize a combination of charged particle and magnetic field observations from the Parker Solar Probe (PSP) to attempt to quantify the steady-state contribution of the proton pressure, the electric potential, and the wave energy to the solar wind proton acceleration observed by PSP between 13.3 and ∼100 solar radii (R
☉). The proton pressure provides a natural kinematic driver of the outflow. The ambipolar electric potential acts to couple the electron pressure to the protons, providing another definite proton acceleration term. Fluctuations and waves, while inherently dynamic, can act as an additional effective steady-state pressure term. To analyze the contributions of these terms, we utilize radial binning of single-point PSP measurements, as well as repeated crossings of the same stream at different distances on individual PSP orbits (i.e., fast radial scans). In agreement with previous work, we find that the electric potential contains sufficient energy to fully explain the acceleration of the slower wind streams. On the other hand, we find that the wave pressure plays an increasingly important role in the faster wind streams. The combination of these terms can explain the continuing acceleration of both slow and fast wind streams beyond 13.3 R
☉.
A VLBI Proper Motion Analysis of the Recoiling Supermassive Black Hole Candidate Mrk 1018
Authors: Walsh Gregory , Burke-Spolaor Sarah , Lazio T. Joseph W. 
Published: July 2023

Abstract
Mrk 1018 is a nearby changing-look active galactic nucleus (AGN) that has oscillated between spectral Type 1.9 and Type 1 over a period of 40 yr. Recently, a recoiling supermassive black hole (rSMBH) scenario has been proposed to explain the spectral and flux variability observed in this AGN. Detections of rSMBHs are important for understanding the processes by which SMBH binaries merge and how rSMBHs influence their galactic environment through feedback mechanisms. However, conclusive identification of any rSMBHs has remained elusive to date. In this paper, we present an analysis of 6.5 yr of multifrequency Very Long Baseline Array monitoring of Mrk 1018. We find that the radio emission is compact down to 2.4 pc, and it displays flux density and spectral variability over the length of our campaign, typical of a flat-spectrum radio core. We observe proper motion in RA of the radio core at −36.4 ± 8.6 μas yr−1 (4.2σ), or 0.10c ± 0.02c at the redshift of Mrk 1018. No significant proper motion is found in DEC (31.3 ± 25.1 μas yr−1). We discuss possible physical mechanisms driving the proper motion, including an rSMBH. We conclude that the apparent velocity we observe of the VLBI radio core is too high to reconcile with theoretical predictions of rSMBH velocities and that the proper motion is most likely dominated by an unresolved, outflowing jet component. Future observations may yet reveal the true nature of Mrk 1018. However, our observations are not able to confirm it as a true rSMBH.
Understanding the Molecular Kinetics and Chemical Equilibrium Phase of Frozen CO during Bombardment by Cosmic Rays by Employing the PROCODA Code
Authors: Pilling S. , Carvalho G. A. , de Abreu H. A. , Galvão B. R. L. , da Silveira C. H. , Mateus M. S. 
Published: July 2023

Abstract
Within the cold regions of space, ices that are enriched with carbon monoxide (CO) molecules are exposed to ionizing radiation, which triggers new reactions and desorption processes. Laboratory studies on astrochemical ices employing different projectiles have revealed the appearance of several new species. In this study, we employed the upgraded PROCODA code, which involves a calculation phase utilizing thermochemistry data, to map the chemical evolution of pure CO ice irradiated by cosmic-ray analogs. In the model, we have considered 18 different chemical species (six observed: CO, CO2, C3, O3, C2O, and C5O3; 12 unobserved: C, O, C2, O2, CO3, C3O, C4O, C5O, C2O2, C2O3, C3O2, and C4O2) coupled at 156 reaction routes. Our best-fit model provides effective reaction rates (effective rate constants, (ERCs)), branching ratios for reactions within reaction groups, several desorption parameters, and the characterization of molecular abundances at the chemical equilibrium (CE) phase. The most abundant species within the ice at the CE phase were atomic oxygen (68.2%) and atomic carbon (18.2%), followed by CO (11.8%) and CO2 (1.6%). The averaged modeled desorption yield and rate were 1.3e5 molecules ion−1 and 7.4e13 molecules s−1, respectively, while the average value of ERCs in the radiation-induced dissociation reactions was 2.4e-1 s−1 and for the bimolecular reactions it was 4.4e-24 cm3 molecule−1 s−1. We believe that the current kinetics study can be used in future astrochemical models to better understand the chemical evolution of embedded species within astrophysical ices under the presence of an ionizing radiation field.
Lensing Reconstruction from the Cosmic Microwave Background Polarization with Machine Learning
Authors: Yan Ye-Peng , Wang Guo-Jian , Li Si-Yu , Yan Yang-Jie , Xia Jun-Qing 
Published: July 2023

Abstract
The lensing effect of the cosmic microwave background (CMB) is a powerful tool for our study of the distribution of matter in the universe. The quadratic estimator (QE) method, which is widely used to reconstruct lensing potential, has been known to be suboptimal for the low noise level polarization data from next-generation CMB experiments. To improve the performance of the reconstruction, other methods, such as the maximum-likelihood estimator and machine-learning algorithms, have been developed. In this work, we present a deep convolutional neural network model named the Residual Dense Local Feature U-net (RDLFUnet) for reconstructing the CMB lensing convergence field. By simulating lensed CMB data with different noise levels to train and test network models, we find that for noise levels less than 5 μK-arcmin, RDLFUnet can recover the input gravitational potential with a higher signal-to-noise ratio than the previous deep-learning and traditional QE methods at almost the entire observation scale.
A Comprehensive Simulation of Solar Wind Formation from the Solar Interior: Significant Cross-field Energy Transport by Interchange Reconnection near the Sun
Authors: Iijima Haruhisa , Matsumoto Takuma , Hotta Hideyuki , Imada Shinsuke 
Published: July 2023

Abstract
The physical connection between thermal convection in the solar interior and the solar wind remains unclear due to their significant scale separation. Using an extended version of the three-dimensional radiative magnetohydrodynamic code RAMENS, we perform the first comprehensive simulation of the solar wind formation, starting from the wave excitation and the small-scale dynamo below the photosphere. The simulation satisfies various observational constraints as a slow solar wind emanating from the coronal hole boundary. The magnetic energy is persistently released in the simulated corona, showing a hot upward flow at the interface between open and closed fields. To evaluate the energetic contributions from Alfvén wave and interchange reconnection, we develop a new method to quantify the cross-field energy transport in the simulated atmosphere. The measured energy transport from closed coronal loops to open field accounts for approximately half of the total. These findings suggest a significant role of the supergranular-scale interchange reconnection in solar wind formation.
ALMA Reveals a Stable Rotating Gas Disk in a Paradoxical Low-mass, Ultradusty Galaxy at z = 4.274
Authors: Pope Alexandra , McKinney Jed , Kamieneski Patrick , Battisti Andrew , Aretxaga Itziar , Brammer Gabriel , Diego Jose M. , Hughes David H. , Keller Erica , Marchesini Danilo , Mizener Andrew , Montaña Alfredo , Murphy Eric , Whitaker Katherine E. , Wilson Grant , Yun Min 
Published: July 2023

Abstract
We report ALMA detections of [C ii] and a dust continuum in Az9, a multiply imaged galaxy behind the Frontier Field cluster MACS J0717.5+3745. The bright [C ii] emission line provides a spectroscopic redshift of z = 4.274. This strongly lensed (μ = 7 ± 1) galaxy has an intrinsic stellar mass of only 2 × 109
M
⊙ and a total star formation rate of 26 M
⊙ yr−1 (∼80% of which is dust-obscured). Using public magnification maps, we reconstruct the [C ii] emission in the source plane to reveal a stable, rotation-dominated disk with V/σ = 5.3, which is >2× higher than predicted from simulations for similarly high-redshift, low-mass galaxies. In the source plane, the [C ii] disk has a half-light radius of 1.8 kpc and, along with the dust, is spatially offset from the peak of the stellar light by 1.4 kpc. Az9 is not deficient in [C ii]; L
[C II]/L
IR = 0.0027, consistent with local and high-redshift normal star-forming galaxies. While dust-obscured star formation is expected to dominate in higher-mass galaxies, such a large reservoir of dust and gas in a lower-mass disk galaxy 1.4 Gyr after the Big Bang challenges our picture of early galaxy evolution. Furthermore, the prevalence of such low-mass dusty galaxies has important implications for the selection of the highest-redshift dropout galaxies with JWST. As one of the lowest stellar mass galaxies at z > 4 to be detected in a dust continuum and [C ii], Az9 is an excellent laboratory in which to study early dust enrichment in the interstellar medium.
Interstellar Comets from Post-main-sequence Systems as Tracers of Extrasolar Oort Clouds
Authors: Levine W. Garrett , Taylor Aster G. , Seligman Darryl Z. , Hoover Devin J. , Jedicke Robert , Bergner Jennifer B. , Laughlin Gregory P. 
Published: July 2023

Abstract
Interstellar small bodies are unique probes into the histories of exoplanetary systems. One hypothesized class of interlopers are “Jurads,” exocomets released into the Milky Way during the post-main-sequence as the thermally pulsing asymptotic giant branch (AGB) host stars lose mass. In this study, we assess the prospects for the Legacy Survey of Space and Time (LSST) to detect a Jurad and examine whether such an interloper would be observationally distinguishable from exocomets ejected during the (pre-)main-sequence. Using analytic and numerical methods, we estimate the fraction of exo–Oort Cloud objects that are released from 1–8 M
⊙ stars during post-main-sequence evolution. We quantify the extent to which small bodies are altered by the increased luminosity and stellar outflows during the AGB, finding that some Jurads may lack hypervolatiles and that stellar winds could deposit dust that covers the entire exocomet surface. Next, we construct models of the interstellar small body reservoir for various size–frequency distributions and examine the LSST’s ability to detect members of those hypothesized populations. Combining these analyses, we highlight the joint constraints that the LSST will place on power-law size–frequency distribution slopes, characteristic sizes, and the total mass sequestered in the minor planets of exo–Oort Clouds. Even with the LSST’s increased search volume compared to contemporary surveys, we find that detecting a Jurad is unlikely but not infeasible given the current understanding of (exo)planet formation.
Demographic and socioeconomic determinants of internet usage in Indonesia
Authors: Rajagukguk Wilson , Heatubun Adolf , Pane Medyawanti 
Published: July 2023

Digital divide is relatively high in Indonesia. This study aimed to investigate the demographic and socioeconomic determinants of internet usage in Indonesia. The data used came from the results of the National Socioeconomic Survey in 2021. The unit analysis was population aged 15 years and above who had at least one digital gadget. The dependent variable was the number of internet usage. The independent variables included gender, age, number of household members, marital status, education, working status, place of dwelling, island of residence, and number of digital gadget type owned. Data analysis was used with univariate, bivariate and multivariate methods. Binary Logistic Regression model is used in multivariate analysis. The results of study indicated that higher internet usage was associated with being male, being younger, having smaller number of household members, being unmarried, having higher education, dwelling in urban areas, living in Java island, and owning more digital gadget types. These findings suggest the need to improve access to higher internet usage among women, older people, married individuals, rural dwellers, and Outer Java inhabitants, to promote family planning, to improve education, and to facilitate access to more digital gadgets in order to reduce digital divide and to boost 4.0 global competitiveness in Indonesia.Digital divide is relatively high in Indonesia. This study aimed to investigate the demographic and socioeconomic determinants of internet usage in Indonesia. The data used came from the results of the National Socioeconomic Survey in 2021. The unit analysis was population aged 15 years and above who had at least one digital gadget. The dependent variable was the number of internet usage. The independent variables included gender, age, number of household members, marital status, education, working status, place of dwelling, island of residence, and number of digital gadget type owned. Data analysis was used with univariate, bivariate and multivariate methods. Binary Logistic Regression model is used in multivariate analysis. The results of study indicated that higher internet usage was associated with being male, being younger, having smaller number of household members, being unmarried, having higher education, dwelling in urban areas, living in Java island, and owning more digital gadget types. These findings suggest the need to improve access to higher internet usage among women, older people, married individuals, rural dwellers, and Outer Java inhabitants, to promote family planning, to improve education, and to facilitate access to more digital gadgets in order to reduce digital divide and to boost 4.0 global competitiveness in Indonesia.
&nbsp;
Analysis of Wavefront Data Obtained With a Pyramidal Sensor in Pseudophakic Eyes Implanted With Diffractive Intraocular Lenses
Authors: Faria-Ribeiro Miguel , González-Méijome José Manuel , Ferreira Maria Isabel Pinho , Morais-Borges Anabela Ferreira , Salgado-Borges José 
Published: July 2023

Purpose:
To investigate the clinical validity of using wavefront measurements obtained with a recently available pyramidal aberrometer to assess the optical quality of eyes implanted with diffractive intraocular lenses (IOLs).

Methods:
Individual biometric data were used to create models of pseudophakic eyes implanted with two diffractive IOLs. Their synthetic wavefronts were calculated by ray-tracing with near infrared wavelength (0.85 μm). Comparisons of the through-focus visual acuity of 12 pseudophakic eyes were obtained with three different methods: clinical defocus curves; simulated defocus curves calculated from ray-tracing in the customized model eyes; and through-focus simulated defocus curves calculated from the wavefront data measured with a pyramidal aberrometer.

Results:
Image quality calculated from wavefront data obtained by ray-tracing with 0.85 μm wavelength, without scaling the phase to 0.55 μm, resulted in a significantly different through-focus curve compared to the reference values. Even so, after scaling of the wavefront data to 0.55 μm, the defocus curves calculated from the wavefronts measured with the pyramidal aberrometer did not match the shape and the depth of field of the clinical defocus curves or the theoretical expected values.

Conclusions:
Correcting for the longitudinal chromatic aberration of the eye when measuring the wavefront of eyes implanted with diffractive IOLs under near infrared light only accounts for the best focus shift due to the longitudinal chromatic aberration, but not for the wavelength dependence of the diffractive element. The pyramidal sensor does not seem to properly sample the slopes of a wavefront measured from a pseudophakic eye implanted with a presbyopia-correcting diffractive IOL to a clinically acceptable level.

[
J Refract Surg
. 2023;39(7):438–444.]
Stratigrafsko najstarejši zgodnjesrednjeveški grobovi in začetek pokopavanja na grobišču Župna cerkev v Kranju
Authors: Rihter Jernej 
Published: July 2023

Članek se ukvarja z analizo grobov, izkopanih pri Župni cerkvi v Kranju, ki so bili na podlagi dosedanjih raziskav opredeljeni kot najstarejši na tem grobišču. Za takšne so bili do zdaj opredeljeni grobovi (večinoma) brez pridatkov, ki so bili globoko vkopani v prostorne in med seboj pravilno razmeščene grobne jame, obložene s kamni oz. lesom in orientirane proti vzhodu. Posamezne skupine takšnih grobov, izkopanih do leta 1984, so bile na podlagi arheoloških primerjav datirane v konec 7. in v 8. st.
Analiza stratigrafije grobov celotnega grobišča, v katero smo vključili tudi ugotovitve poznejših izkopavanj in pregled zgodovine raziskav, pokažejo, da pri grobovih, do zdaj opredeljenih kot najstarejših, ni šlo vselej za stratigrafsko najstarejše grobove in da so bile med nekaterimi tudi superpozicije.
V prispevku skušamo ugotoviti čas začetka pokopavanja na podlagi starih in novih kronoloških podatkov (relativna kronologija grobov in tipokronologija). Za izbrane stratigrafsko najstarejše grobove na tem grobišču prvič prinašamo radiokarbonske datacije (14C), ki smo jih časovno zožili z datacijami stratigrafsko mlajših grobov s predmeti. Obravnavani grobovi se po gradnji groba ločijo na dve skupini. Pokopavanje se je začelo najverjetneje v 8. st., pred letom 774/775 (14C) s prvo skupino, z možnim trajanjem vse do začetka pokopavanja druge skupine. Druga skupina grobov ni starejša od leta 774 in se je začela že pred začetkom 9. st. ali najpozneje takrat.