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In sunspot umbrae, the core of some chromospheric lines exhibits periodic brightness enhancements known as umbral flashes. The consensus is that they are produced by the upward propagation of shock waves. This view has recently been challenged by the detection of downflowing umbral flashes and the confirmation of the existence of a resonant cavity above sunspots. We aim to determine waves' propagating or standing nature in the low umbral chromosphere and confirm or refute the existence of downflowing umbral flashes. Spectroscopic temporal series of Ca II 8542 \AA, Ca II H, and Halpha in a sunspot were acquired with the Swedish Solar Telescope. The Halpha velocity was inferred using bisectors. Simultaneous inversions of the Ca II 8542 \AA\ line and the Ca II H core were performed using the NICOLE code. The nature of the oscillations and insights into the resonant oscillatory pattern were determined by analyzing the phase shift between the velocity signals and examining the temporal evolution. Propagating waves in the low chromosphere are more common in regions with frequent umbral flashes, where the transition region is shifted upward, making resonant cavity signatures less noticeable. In contrast, areas with fewer umbral flashes show velocity fluctuations that align with standing oscillations. Evidence suggests dynamic changes in the location of velocity resonant nodes due to variations in transition region height. Downflowing profiles appear at the onset of some umbral flashes, but upflowing motion dominates during most of the flash. These downflowing flashes are more common in standing umbral flashes. We confirm the existence of a chromospheric resonant cavity above sunspot umbrae produced by wave reflections at the transition region. The oscillatory pattern depends on the transition region height, which exhibits spatial and temporal variations due to the impact of the waves., Comment: Accepted for publication in A&A

Large Language Models based on transformer algorithms have revolutionized Artificial Intelligence by enabling verbal interaction with machines akin to human conversation. These AI agents have surpassed the Turing Test, achieving confusion rates up to 50%. However, challenges persist, especially with the advent of robots and the need to humanize machines for improved Human-AI collaboration. In this experiment, three GPT agents with varying levels of agreeableness (disagreeable, neutral, agreeable) based on the Big Five Inventory were tested in a Turing Test. All exceeded a 50% confusion rate, with the highly agreeable AI agent surpassing 60%. This agent was also recognized as exhibiting the most human-like traits. Various explanations in the literature address why these GPT agents were perceived as human, including psychological frameworks for understanding anthropomorphism. These findings highlight the importance of personality engineering as an emerging discipline in artificial intelligence, calling for collaboration with psychology to develop ergonomic psychological models that enhance system adaptability in collaborative activities., Comment: 25 pages, 2 figures, 7 tables

Kinetic inductance detectors (KIDs) have been proven as reliable systems for astrophysical observations, especially in the millimetre range. Their compact size enables to optimally fill the focal plane, thus boosting sensitivity. The KISS (KIDs Interferometric Spectral Surveyor) instrument is a millimetre camera that consists of two KID arrays of 316 pixels each coupled to a Martin-Puplett interferometer (MPI). The addition of the MPI grants the KIDs camera the ability to provide spectral information in the 100 and 300 GHz range. In this paper we report the main properties of the KISS instrument and its observations. We also describe the calibration and data analysis procedures used. We present a complete model of the observed data including the sky signal and several identified systematics. We have developed a full photometric and spectroscopic data analysis pipeline that translates our observations into science-ready products. We show examples of the results of this pipeline on selected sources: Moon, Jupiter and Venus. We note the presence of a deficit of response with respect to expectations and laboratory measurements. The detectors noise level is consistent with values obtained during laboratory measurements, pointing to a sub-optimal coupling between the instrument and the telescope as the most probable origin for the problem. This deficit is large enough as to prevent the detection of galaxy clusters, which were KISS main scientific objective. Nevertheless, we have demonstrated the feasibility of this kind of instrument, in the prospect for other KID interferometers (such as the CONCERTO instrument). As this regard, we have developed key instrumental technologies such as optical conception, readout electronics and raw calibration procedures, as well as, adapted data analysis procedures., Comment: 23 pages, 15 figures. Accepted for publication in Publications of the Astronomical Society of the Pacific

The Gemini South telescope is now equipped with a new high-resolution spectrograph called GHOST (the Gemini High-resolution Optical SpecTrograph). This instrument provides high-efficiency, high-resolution spectra covering 347-1060 nm in a single exposure of either one or two targets simultaneously, along with precision radial velocity spectroscopy utilizing an internal calibration source. It can operate at a spectral element resolving power of either 76000 or 56000, and can reach a SNR$\sim$5 in a 1hr exposure on a V$\sim$20.8 mag target in median site seeing, and dark skies (per resolution element). GHOST was installed on-site in June 2022, and we report performance after full integration to queue operations in November 2023, in addition to scientific results enabled by the integration observing runs. These results demonstrate the ability to observe a wide variety of bright and faint targets with high efficiency and precision. With GHOST, new avenues to explore high-resolution spectroscopy have opened up to the astronomical community. These are described, along with the planned and potential upgrades to the instrument., Comment: Accepted in the Astronomical Journal; 26 pages, 24 figures and 4 tables

This paper presents the work carried out by the ASASVIcomtech team, made up of researchers from Vicomtech and University of Granada, for the ASVspoof5 Challenge. The team has participated in both Track 1 (speech deepfake detection) and Track 2 (spoofing-aware speaker verification). This work started with an analysis of the challenge available data, which was regarded as an essential step to avoid later potential biases of the trained models, and whose main conclusions are presented here. With respect to the proposed approaches, a closed-condition system employing a deep complex convolutional recurrent architecture was developed for Track 1, although, unfortunately, no noteworthy results were achieved. On the other hand, different possibilities of open-condition systems, based on leveraging self-supervised models, augmented training data from previous challenges, and novel vocoders, were explored for both tracks, finally achieving very competitive results with an ensemble system., Comment: This paper was accepted at ASVspoof Workshop 2024

Symbiotic systems often include an asymptotic giant branch (AGB) star and a hot compact companion, such as a white dwarf, that are in close interaction. Due to the intense ultraviolet emission from the hot companion, the molecular content of circumstellar envelopes in the symbiotic systems is poor. As a result, the less abundant molecules have not been previously studied in detail in this kind of object. R Aqr is the closest and best-studied symbiotic system. We obtain the spatial distribution of the recombination line H30{\alpha} with a high and moderate angular resolution, and it is compared with the emission of the continuum at 1.3 mm. High-resolution maps of several molecules are also obtained in the three observed ALMA bands. We study the molecular emissions using a simplified model to explain the brightness distributions seen in the central position of our maps. We find that the low-resolution continuum map at 1.3mm shows the emission of the radio photosphere of the AGB star, its surroundings, and the structure of the bipolar jet launched by the companion. The high-resolution continuum map at 1.3mm shows the innermost part of the jet, probably revealing the position of the secondary, and suggests mass transfer from the AGB star to the white dwarf. The brightness distribution of H30{\alpha} is similar but not coincident with the continuum emission. The brightness distributions of the studied molecular lines show a variety of shapes. The emissions of the abundant molecules, CO and SiO, are relatively extended since they can survive far from the AGB star in spite of the intense ultraviolet emission from the white dwarf. On the contrary, less abundant molecules only survive in regions close to the AGB star, where shielding is stronger. From our best-fit model for these weak species, we find that these less abundant species are confined to the intra-orbital regions.

We give an overview of the theoretical description of nuclear reactions involving weakly-bound nuclei. Some of the more widespread reaction formalisms employed in the analysis of these reactions are briefly introduced, including various recent developments. We put special emphasis on the continuum-discretized coupled-channel (CDCC) method and its extensions to incorporate core and target excitations as well as its application to three-body projectiles. The role of the continuum for one-nucleon transfer reactions is also discussed. The problem of the evaluation of inclusive breakup cross sections is addressed within the Ichimura-Austern-Vincent (IAV) model. Other methods, such as those based on a semiclasical description of the scattering process, are also briefly introduced and some of their applications are discussed and a brief discussion on topics of current interest, such as nucleon-nucleon correlations, uncertainty evaluation and non-locality is presented., Comment: review paper; submitted to EPJA; revised version with amendments and additions

In this work, we present the first, to our knowledge, theoretical description of two-proton removal reactions with proton target $(p,3p)$ for medium-mass nuclei at intermediate energies and present cross sections for the different bound states of the residual nucleus with two fewer protons. The description of the reaction assumes two sequential ``quasifree'' collisions between the target and removed protons and considers eikonal propagation in between. The formalism is applied to the reactions $^{12}\mathrm{C}(p,3p)^{10}\mathrm{Be}$, $^{28}\mathrm{Mg}(p,3p)^{26}\mathrm{Ne}$ and $^{54}\mathrm{Ca}(p,3p)^{52}\mathrm{Ar}$, finding reasonable agreement to experimental data for the $^{12}$C target and an overestimation of a factor $\sim3$ for the more neutron-rich and $^{54}$Ca, which is similar to the results found in two-proton knockout experiments with $^9$Be and $^{12}$C targets., Comment: 10 pages, 2 figures

CHEOPS is a space telescope specifically designed to monitor transiting exoplanets orbiting bright stars. In September 2023, CHEOPS completed its nominal mission and remains in excellent operational conditions. The mission has been extended until the end of 2026. Scientific and instrumental data have been collected throughout in-orbit commissioning and nominal operations, enabling a comprehensive analysis of the mission's performance. In this article, we present the results of this analysis with a twofold goal. First, we aim to inform the scientific community about the present status of the mission and what can be expected as the instrument ages. Secondly, we intend for this publication to serve as a legacy document for future missions, providing insights and lessons learned from the successful operation of CHEOPS. To evaluate the instrument performance in flight, we developed a comprehensive monitoring and characterisation programme. It consists of dedicated observations that allow us to characterise the instrument's response. In addition to the standard collection of nominal science and housekeeping data, these observations provide input for detecting, modelling, and correcting instrument systematics, discovering and addressing anomalies, and comparing the instrument's actual performance with expectations. The precision of the CHEOPS measurements has enabled the mission objectives to be met and exceeded. Careful modelling of the instrumental systematics allows the data quality to be significantly improved during the light curve analysis phase, resulting in more precise scientific measurements. CHEOPS is compliant with the driving scientific requirements of the mission. Although visible, the ageing of the instrument has not affected the mission's performance., Comment: Accepted for publication in Astronomy and Astrophysics

The optimization of chemical processes is challenging due to the nonlinearities arising from process physics and discrete design decisions. In particular, optimal synthesis and design of chemical processes can be posed as a Generalized Disjunctive Programming (GDP) superstructure problem. Various solution methods are available to address these problems, such as reformulating them as Mixed-Integer Nonlinear Programming (MINLP) problems; nevertheless, algorithms explicitly designed to solve the GDP problem and potentially leverage its structure remain scarce. This paper presents the Logic-based Discrete-Steepest Descent Algorithm (LD-SDA) as a solution method for GDP problems involving ordered Boolean variables. The LD-SDA reformulates these ordered Boolean variables into integer decisions called external variables. The LD-SDA solves the reformulated GDP problem using a two-level decomposition approach where the upper-level subproblem determines external variable configurations. Subsequently, the remaining continuous and discrete variables are solved as a subproblem only involving those constraints relevant to the given external variable arrangement, effectively taking advantage of the structure of the GDP problem. The advantages of LD-SDA are illustrated through a batch processing case study, a reactor superstructure, a distillation column, and a catalytic distillation column, and its open-source implementation is available online. The results show convergence efficiency and solution quality improvements compared to conventional GDP and MINLP solvers., Comment: 34 pages, 14 figures

Fullerenes have been observed in several astronomical objects since the discovery of C$_{60}$ in the mid-infrared (mid-IR) spectrum of the planetary nebula (PN) Tc 1. It has been suggested that the carriers of the broad unidentified infrared (UIR) plateau features, such as the 9$-$13$\mu$m emission feature (12$\mu$m hereafter), may be related to the formation of fullerenes. In particular, their carriers have been suggested to be mixed aromatic or aliphatic hydrocarbons such as hydrogenated amorphous carbon (HAC-like hereafter) grains. For this study, we modeled the mid-IR emission of the C$_{60}$-PN Tc 1 with a photoionization code, including for the first time the laboratory optical constants ($n$ and $k$ indices) of HAC-like dust at 300 K. Interestingly, we find that the broad 12$\mu$m plateau feature in Tc 1 is well reproduced by using a distribution of canonical HAC grains, while at the same time they provide an important fraction of the IR dust continuum emission and are consistent with the other UIR features observed (e.g., the broad 6$-$9$\mu$m plateau feature). This finding suggests that HAC-like grains may be possible carriers of the 12$\mu$m plateau feature, being likely related to the fullerene formation mechanism in PNe. More laboratory experiments, to obtain the optical constants of HAC-like dust with several structures or a composition at different physical conditions, are strongly encouraged -- that is, in order to extend this pilot study to more fullerene PNe, and to unveil the details of fullerene formation and of the potential carriers of the elusive UIR plateau features., Comment: Published in Astronomy and Astrophysics Letters. 7 pages, 3 figures

Solar partially ionized plasma is frequently modeled using single-fluid (1F) or two-fluid (2F) approaches. In the 1F case, charge-neutral interactions are often described through ambipolar diffusion, while the 2F model fully considers charge-neutral drifts. Here, we expand the definition of the ambipolar diffusion coefficient to include inelastic collisions (ion/rec) in two cases: a VAL3C 1D model and a 2F simulations of the Rayleigh-Taylor instability (RTI) in a solar prominence thread based on \cite{PopLukKho2021aa, PopLukKho2021ab}. On one side, we evaluate the relative importance of the inelastic contribution, compared to elastic and charge-exchange collisions. On the other side, we compare the contributions of ion/rec, thermal pressure, viscosity, and magnetic forces to the charge-neutral drift velocity of the turbulent flow of the RTI. Our analysis reveals that the contribution of inelastic collisions to the ambipolar diffusion coefficient is negligible across the chromosphere, allowing the classical definition of this coefficient to be safely used in 1F modeling. However, in the transition region, the contribution of inelastic collisions can become as significant as that of elastic collisions. Furthermore, we ascertain that the thermal pressure force predominantly influences the charge-neutral drifts in the RTI model, surpassing the impact of the magnetic force., Comment: Accepted

Kinematically-persistent planes of satellites (KPPs) are fixed sets of satellites co-orbiting around their host galaxy, whose orbital poles are conserved and clustered across long cosmic time intervals. They play the role of 'skeletons', ensuring the long-term durability of positional planes. We explore the physical processes behind their formation in terms of the dynamics of the local Cosmic Web (CW), characterized via the so-called Lagrangian Volumes (LVs) built up around two zoom-in, cosmological hydro-simulations of MW-mass disk galaxy + satellites systems, where three KPPs have been identified. By analyzing the LVs deformations in terms of the reduced Tensor of Inertia (TOI), we find an outstanding alignment between the LV principal directions and KPP satellites' orbital poles. The most compressive local mass flows (along the $\hat{e}_3$ eigenvector) are strong at early times, feeding the so-called $\hat{e}_3$-structure, while the smallest TOI axis rapidly decreases. The $\hat{e}_3$-structure collapse marks the end of this regime and is the timescale for the establishment of satellite orbital pole clustering when the Universe is $\lesssim$ 4 Gyr old. KPP proto-satellites aligned with $\hat{e}_3$ are those whose orbital poles are either aligned from early times, or have been successfully bent at $\hat{e}_3$-structure collapse. KPP satellites associated to $\hat{e}_1$ tend to have early trajectories already parallel to $\hat{e}_3$. We show that KPPs can arise as a result of the $\Lambda$CDM-predicted large-scale dynamics acting on particular sets of proto-satellites, the same dynamics that shape the local CW environment., Comment: 27 pages, 12 figures, 2 tables. Accepted for publication in The Astrophysical Journal

A joint campaign of several space-borne and ground-based observatories, such as the GREGOR solar telescope, the Extreme-ultraviolet Imaging Spectrometer (EIS), and the Interface Region Imaging Spectrograph (Hinode Observing Plan 381, 11-22 October 2019) was conducted to investigate the plasma $\beta$ in quiet sun regions. In this work, we focus on October 13, 17, and 19, 2019, to obtain the plasma $\beta$ at different heights through the solar atmosphere based on multi-height observational data. We obtained temperature, density and magnetic field estimates from the GREGOR High-resolution Fast Imager (HiFI), and Infrared Spectrograph (GRIS), IRIS, EIS and complementary data from SDO/AIA. Using observational data and models (e.g., FALC and PFSS), we determined the plasma $\beta$ in the photosphere, chromosphere, transition region and corona. The obtained plasma $\beta$ values lie inside the expected ranges through the solar atmosphere. However, at EIS and AIA coronal heights (from $1.03\ R_{\odot}$ to $1.20\ R_{\odot}$) plasma $\beta$ values appear in the limit defined by Gary (2001); such behavior was previously reported by Rodr\'iguez G\'omez et al. (2019). Additionally, we obtained the plasma $\beta$ in the solar photosphere at different optical depths from $\log\ \tau=-1.0$ to $\log\ \tau=-2.0$. These values decrease with optical depth. This work provides a complete picture of plasma $\beta$ in quiet sun regions through the solar atmosphere, which is a pre-requisite of a better understanding of the plasma dynamics at the base of the solar corona.

The sulfur dimer (S$_2$) is an important molecular constituent in cometary atmospheres and volcanic plumes on Jupiter's moon Io. It is also expected to play an important role in the photochemistry of exoplanets. The UV spectrum of S$_2$ contains transitions between vibronic levels above and below the dissociation limit, giving rise to a distinctive spectral signature. By using spectroscopic information from the literature, and the spectral simulation program PGOPHER, a UV line list of S$_2$ is provided. This line list includes the primary $B\,^{3}\Sigma^{-}_{u}-X\,^{3}\Sigma^{-}_{g}$ ($v'$=0-27, $v''$=0-10) electronic transition, where vibrational bands with $v'$$\geq$10 are predissociated. Intensities have been calculated from existing experimental and theoretical oscillator strengths, and semi-empirical strengths for the predissociated bands of S$_2$ have been derived from comparisons with experimental cross-sections. The S$_2$ line list also includes the $B''\,^{3}\Pi_{u}-X\,^{3}\Sigma^{-}_{g}$ ($v'$=0-19, $v''$=0-10) vibronic bands due to the strong interaction with the $B$ state. In summary, we present the new HITRAN-formatted S$_2$ line list and its validation against existing laboratory spectra. The extensive line list covers the spectral range 21700$-$41300~cm$^{-1}$ ($\sim$242$-$461~nm) and can be used for modeling both absorption and emission., Comment: Accepted to the Monthly Notices of the Royal Astronomical Society

Several planetary nebulae (PNe) have been found to contain both polycyclic aromatic hydrocarbon (PAH-like) species and fullerenes (C$_{60}$) distinguished by their mid-infrared emission. Previous laboratory and astronomical studies suggest that the formation of both species could be related to the decomposition, by photochemical processing, of hydrogenated amorphous carbon (HAC) grains. Then, HACs and, seemingly, big-fullerene related species (e.g., carbon onions) have been suggested as potential carriers of the UV bump at 2175{\AA} and the far-UV rise common to interstellar extinction curves. Our goal is to investigate the UV bump with the possible presence of a HAC extinction component in the International Ultraviolet Explorer (IUE) spectra of C-rich PNe; both with detected and non-detected fullerenes. The considered sample includes three C$_{60}$-PNe (Tc 1, IC 418, and IC 2501) and the non-C$_{60}$-PN Hen 2-5. Independently of the presence of C$_{60}$ in their circumstellar envelopes, we found that the UV bump in all sample PNe is well explained by interstellar extinction, suggesting that species different from those of the foreground insterstellar medium, e.g., large fullerene-related species like carbon onions, are not the carrier. Interestingly, we found that PNe Tc 1 and Hen 2-5 show an absorption in the FUV rise. Their IUE continuum spectra may be very well reproduced by including the extinction curve of HAC-like very small grains (VSG). The possible presence of both species, HAC-like grains and fullerenes (C$_{60}$), in Tc 1 could support the HAC photochemical processing scenario for the formation of fullerenes in the complex circumstellar envelopes of PNe., Comment: 9 pages, 8 figures. Accepted for publication in MNRAS

The optical floating zone crystal growth technique is a well-established method for obtaining large, high-purity single crystals. While the floating zone method has been constantly evolving for over six decades, the development of high-pressure (up to 1000 bar) growth systems has only recently been realized via the combination of laser-based heating sources with an all-metal chamber. While our inaugural high-pressure laser floating zone furnace design demonstrated the successful growth of new volatile and metastable phases, the furnace design faces several limitations with imaging quality, heating profile control, and chamber cooling power. Here, we present a second-generation design of the high-pressure laser floating zone furnace, "Laser Optical Kristallmacher II" (LOKII), and demonstrate that this redesign facilitates new advances in crystal growth by highlighting several exemplar materials: ${\alpha}$-Fe$_2$O$_3$, $\beta$-Ga$_2$O$_3$, and La$_2$CuO$_{4+{\delta}}$. Notably, for La$_2$CuO$_{4+{\delta}}$, we demonstrate the feasibility and long-term stability of traveling solvent floating zone growth under a record pressure of 700 bar., Comment: 9 pages, 6 figures

In deep learning for drug discovery, chemical data are often represented as simplified molecular-input line-entry system (SMILES) sequences which allow for straightforward implementation of natural language processing methodologies, one being the sequence-to-sequence autoencoder. However, we observe that training an autoencoder solely on SMILES is insufficient to learn molecular representations that are semantically meaningful, where semantics are defined by the structural (graph-to-graph) similarities between molecules. We demonstrate by example that autoencoders may map structurally similar molecules to distant codes, resulting in an incoherent latent space that does not respect the structural similarities between molecules. To address this shortcoming we propose Semantically-Aware Latent Space Autoencoder (SALSA), a transformer-autoencoder modified with a contrastive task, tailored specifically to learn graph-to-graph similarity between molecules. Formally, the contrastive objective is to map structurally similar molecules (separated by a single graph edit) to nearby codes in the latent space. To accomplish this, we generate a novel dataset comprised of sets of structurally similar molecules and opt for a supervised contrastive loss that is able to incorporate full sets of positive samples. We compare SALSA to its ablated counterparts, and show empirically that the composed training objective (reconstruction and contrastive task) leads to a higher quality latent space that is more 1) structurally-aware, 2) semantically continuous, and 3) property-aware.

Small metal-containing molecules have been detected and recognized as one of the hybrid species efficiently formed in space; especially in the circumstellar envelopes of evolved stars. It has been predicted also that more complex hybrid species like those formed by metals and fullerenes (metallofullerenes) could be present in such circumstellar environments. Recently, quantum-chemical simulations of metallofullerenes have shown that they are potential emitters contributing to the observed mid-IR spectra in the fullerene-rich circumstellar environments of different types of evolved stars. Here we present the individual simulated mid-IR (~5-50 um) spectra of twenty-eight metallofullerene species; both neutral and charged endo- and exohedral metallofullerenes for seven different metals (Li, Na, K, Ca, Mg, Ti, and Fe) have been considered. The changes induced by the metal-C60 interaction on the intensity and position of the spectral features are highlighted using charge density difference maps and electron density partitioning. Our calculations identify the fundamental IR spectral regions where, depending on the metal binding nature, there should be a major spectral contribution from each of the metallofullerenes. The metallofullerenes IR spectra are made publicly available to the astronomical community, especially James Webb Space Telescope users, for comparisons that could eventually lead to the detection of these species in space., Comment: Accepted for publication in The Astrophysical Journal Supplement Series on 19 September 2023 (in press) (13 pages, 7 figures, and 1 table)

The Directorate General for Parliamentary Research Services of the European Parliament has prepared a report to the Members of the European Parliament where they enumerate seven main risks of Artificial Intelligence (AI) in medicine and healthcare: patient harm due to AI errors, misuse of medical AI tools, bias in AI and the perpetuation of existing inequities, lack of transparency, privacy and security issues, gaps in accountability, and obstacles in implementation. In this study, we propose fourteen functional requirements that AI systems may implement to reduce the risks associated with their medical purpose: AI passport, User management, Regulation check, Academic use only disclaimer, data quality assessment, Clinicians double check, Continuous performance evaluation, Audit trail, Continuous usability test, Review of retrospective/simulated cases, Bias check, eXplainable AI, Encryption and use of field-tested libraries, and Semantic interoperability. Our intention here is to provide specific high-level specifications of technical solutions to ensure continuous good performance and use of AI systems to benefit patients in compliance with the future EU regulatory framework., Comment: 14 pages, 1 figure, 1 table

Stellar flares cannot be spatially resolved, which complicates ascertaining the physical processes behind particular spectral signatures. Due to their proximity to Earth, solar flares can serve as a stepping stone for understanding their stellar counterparts, especially when using a Sun-as-a-star instrument and in combination with spatially resolved observations. We aim to understand the disk-integrated spectral behaviors of a confined X2.2 solar flare and its eruptive X9.3 successor as measured by HARPS-N. The behavior of multiple photospheric and chromospheric spectral lines are investigated by means of activity indices and contrast profiles. A number of different photospheric lines were also investigated by means of equivalent widths, and radial velocity measures, which are then related to physical processes directly observed in high-resolution observations made with the Swedish 1-meter Solar Telescope and SDO Our findings suggest a relationship between the evolving shapes of contrast profile time and the flare locations, which assists in constraining flare locations in disk-integrated observations. In addition, an upward bias was found in flare statistics based on activity indices derived from the Ca II H & K lines. In this case, much smaller flares cause a similar increase in the activity index as that produced by larger flares. H$\alpha$-based activity indices do not show this bias and are therefore less susceptible to activity jitter. Sodium line profiles show a strongly asymmetric response during flare activity, which is best captured with a newly defined asymmetrical sodium activity index. A strong flare response was detected in Mn I line profiles, which is unexpected and calls for further exploration. Intensity increases in H$\alpha$, H$\beta$, and certain spectral windows of AIA before the flare onset suggest their potential use as short-term flare predictors., Comment: Published in A&A; Volume 682, A46 (20 pages, 14 figures) doi:10.1051/0004-6361/202347895

The dineutron correlation is systematically studied in three different Borromean nuclei near the neutron dripline, 11Li, 14Be and 17B, via the (p, pn) knockout reaction measured at the RIBF facility in RIKEN. For the three nuclei, the correlation angle between the valence neutrons is found to be largest in the same range of intrinsic momenta, which can be associated to the nuclear surface. This result reinforces the prediction that the formation of the dineutron is universal in environments with low neutron density, such as the surface of neutron-rich Borromean nuclei.

We report the discovery by the TESS mission of a super-Earth on a 4.8-d orbit around an inactive M4.5 dwarf (TOI-1680) validated by ground-based facilities. The host star is located 37.14 pc away, with a radius of 0.2100+/-0.0064 R_sun, mass of 0.1800+/-0.0044 M_sun and an effective temperature of 3211+/-100 K. We validated and characterized the planet using TESS data, ground-based multi-wavelength photometry from TRAPPIST, SPECULOOS, and LCO, as well as high-resolution AO observations from Keck/NIRC2 and Shane. Our analyses have determined the following parameters for the planet: a radius of 1.466+0.063/-0.049 R_earth and an equilibrium temperature of 404+/-14 K, assuming no albedo and perfect heat redistribution. Assuming a mass based on mass-radius relations, this planet is a promising target for atmospheric characterization with the James Webb Space Telescope (JWST)., Comment: Accepted in A&A

A comprehensive multi-wavelength campaign has been carried out to probe stellar activity and variability in the young Sun-like star $\iota$-Horologii. We present the results from long-term spectropolarimetric monitoring of the system by using the ultra-stable spectropolarimeter/velocimeter HARPS at the ESO 3.6-m telescope. Additionally, we included high-precision photometry from the NASA Transiting Exoplanet Survey Satellite (TESS) and observations in the far- and near-ultraviolet spectral regions using the STIS instrument on the NASA/ESA Hubble Space Telescope (HST). The high-quality dataset allows a robust characterisation of the star's rotation period, as well as a probe of the variability using a range of spectroscopic and photometric activity proxies. By analyzing the gradient of the power spectra (GPS) of the TESS lightcurves we constrained the faculae-to-spot driver ratio ($\rm S_{fac}/S_{spot}$) to 0.510$\pm$0.023, which indicates that the stellar surface is spot dominated during the time of the observations. We compared the photospheric activity properties derived from the GPS method with a magnetic field map of the star derived using Zeeman-Doppler imaging (ZDI) from simultaneous spectropolarimetric data for the first time. Different stellar activity proxies enable a more complete interpretation of the observed variability. For example, we observed enhanced emission in the HST transition line diagnostics C IV and C III, suggesting a flaring event. From the analysis of TESS data acquired simultaneously with the HST data, we investigate the photometric variability at the precise moment that the emission increased and derive correlations between different observables, probing the star from its photosphere to its corona.

We investigated the origin of the Planetary Nebula (PN) M 1-16 using narrow-band optical imaging, and high- and low-resolution optical spectra to perform a detailed morpho-kinematic and chemical studies. M 1-16 is revealed to be a multipolar PN that predominantly emits in [O III] in the inner part of the nebula and [N II] in the lobes. A novel spectral unsharp masking technique was applied to the position-velocity (PV) maps to reveal a set of multiple structures at the centre of M 1-16 spanning radial velocities from $-$40km$\,$s$^{-1}$ to 20km$\,$s$^{-1}$, with respect to the systemic velocity. The morpho-kinematic model indicates that the deprojected velocity of the lobe outflows are $\geq$100km$\,$s$^{-1}$, and particularly the larger lobes and knots have a deprojected velocity of $\simeq$350km$\,$s$^{-1}$; the inner ellipsoidal component has a deprojected velocity of $\simeq$29km$\,$s$^{-1}$. A kinematical age of $\sim$8700yr has been obtained from the model assuming a homologous velocity expansion law and a distance of 6.2$\pm$1.9kpc. The chemical analysis indicates that M 1-16 is a Type I PN with a central star of PN (CSPN) mass in the range of $\simeq$0.618-0.713M$_\odot$ and an initial mass for the progenitor star between 2.0 and 3.0M$_\odot$ (depending on metallicity). An $T_\mathrm{eff}\simeq$140$\,$000K and log$(L/L_{\odot})$=2.3 was estimated using the 3MdB photoionisation models to reproduce the ionisation stage of the PN. All of these results have led us to suggest that M 1-16 is an evolved PN, contrary to the scenario of proto-PN suggested in previous studies. We propose that the mechanism responsible for the morphology of M 1-16 is related to the binary (or multiple star) evolution scenario., Comment: A&A in press. 11 pages, 9 figures

The regeneration of the ruptured scapholunate interosseous ligament (SLIL) represents a clinical challenge. Here, we propose the use of a Bone-Ligament-Bone (BLB) 3D-printed polyethylene terephthalate (PET) scaffold for achieving mechanical stabilisation of the scaphoid and lunate following SLIL rupture. The BLB scaffold featured two bone compartments bridged by aligned fibres (ligament compartment) mimicking the architecture of the native tissue. The scaffold presented tensile stiffness in the range of 260+/-38 N/mm and ultimate load of 113+/-13 N, which would support physiological loading. A finite element analysis, using inverse finite element analysis for material property identification, showed an adequate fit between simulation and experimental data. The scaffold was then biofunctionalized using two different methods: injected with a Gelatin Methacryloyl solution containing human mesenchymal stem cell spheroids or seeded with tendon-derived stem cells and placed in a bioreactor to undergo cyclic deformation. The first approach demonstrated high cell viability, as cells migrated out of the spheroid and colonised the interstitial space of the scaffold. These cells adopted an elongated morphology suggesting the internal architecture of the scaffold exerted topographical guidance. The second method demonstrated the high resilience of the scaffold to cyclic deformation and the secretion of a fibroblastic related protein was enhanced by the mechanical stimulation. This process promoted the expression of relevant proteins, such as Tenomodulin, indicating mechanical stimulation may enhance cell differentiation and be useful prior to surgical implantation. In conclusion, the PET scaffold presented several promising characteristics for the immediate mechanical stabilisation of disassociated scaphoid and lunate and, in the longer-term, the regeneration of the ruptured SLIL.

Planetary nebulae (PNe) consist of an ionized envelope surrounding a hot central star (CSPN) that emits mostly at ultraviolet (UV) wavelengths. Ultraviolet observations, therefore, provide important information on both the CSPN and the nebula. We have matched the PNe in The Hong Kong/AAO/Strasbourg H$\alpha$ (HASH) catalog with the Galaxy Evolution Explorer (GALEX) UV sky surveys, the Sloan Digital Sky Survey data release 16 (SDSS), and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) PS1 second release. A total of 671 PNe were observed by GALEX with the far-UV (FUV; 1344-1786{\AA}) and/or the near-UV (NUV; 1771-2831{\AA}) detector on (GUVPNcat); 83 were observed by SDSS (PNcatxSDSSDR16) and 1819 by Pan-STARRS (PNcatxPS1MDS). We merged a distilled version of these matched catalogs into GUVPNcatxSDSSDR16xPS1MDS, which contains a total of 375 PNe with both UV and optical photometry over a total spectral coverage of $\sim$1540--9610{\AA}. We analysed separately 170 PNe resolved in GALEX images and determined their UV radius by applying a flux profile analysis. The CSPN flux could be extracted separately from the PN emission for 8 and 50 objects with SDSS and Pan-STARRS counterparts respectively. The multi-band photometry was used to distinguish between compact and extended PNe and CSPNe (binary CSPNe) by color--color diagram analysis. We found that compact PNe candidates could be identified by using the $r-i < -0.4$ and $-$1$<$FUV$-$NUV$<$1 colors, whereas binary CSPNe candidates in given $T_\mathrm{eff}$ ranges (all with color r$-$i$>-$0.4) can be identified in the color region (FUV$-$NUV)$\leq$6(r$-$i)+1.3, $-$0.8$<$FUV$-$NUV$<$0.4 and r$-$i$<$0.75., Comment: Accepted for publication in ApJS. 26 pages, 8 figures

Several planetary formation models have been proposed to explain the observed abundance and variety of compositions of super-Earths and mini-Neptunes. In this context, multitransiting systems orbiting low-mass stars whose planets are close to the radius valley are benchmark systems, which help to elucidate which formation model dominates. We report the discovery, validation, and initial characterization of one such system, TOI-2096, composed of a super-Earth and a mini-Neptune hosted by a mid-type M dwarf located 48 pc away. We first characterized the host star by combining different methods. Then, we derived the planetary properties by modeling the photometric data from TESS and ground-based facilities. We used archival data, high-resolution imaging, and statistical validation to support our planetary interpretation. We found that TOI-2096 corresponds to a dwarf star of spectral type M4. It harbors a super-Earth (R$\sim1.2 R_{\oplus}$) and a mini-Neptune (R$\sim1.90 R_{\oplus}$) in likely slightly eccentric orbits with orbital periods of 3.12 d and 6.39 d, respectively. These orbital periods are close to the first-order 2:1 mean-motion resonance (MMR), which may lead to measurable transit timing variations (TTVs). We computed the expected TTVs amplitude for each planet and found that they might be measurable with high-precision photometry delivering mid-transit times with accuracies of $\lesssim$2 min. Moreover, measuring the planetary masses via radial velocities (RVs) is also possible. Lastly, we found that these planets are among the best in their class to conduct atmospheric studies using the James Webb Space Telescope (JWST). The properties of this system make it a suitable candidate for further studies, particularly for mass determination using RVs and/or TTVs, decreasing the scarcity of systems that can be used to test planetary formation models around low-mass stars., Comment: 25 pages, 21 figures. Aceptted for publication in Astronomy & Astrophysics

The direct reaction theory widely used to study single-particle spectroscopic strength in nucleon transfer experiments is based on a Hamiltonian with two-nucleon interactions only. We point out that in reactions with a loosely-bound projectile, where clustering and breakup effects are important, an additional three-body force arises due to three-nucleon ($3N$) interaction between two nucleons belonging to different clusters in the projectile and a target nucleon. We study the effects of this force on nucleon transfer in $(d,p)$ and $(d,n)$ reactions on $^{56}$Ni, $^{48}$Ca, $^{26m}$Al and $^{24}$O targets at deuteron incident energies between 4 and 40 MeV/nucleon. Deuteron breakup is treated exactly within a continuum discretized coupled-channel approach. It was found that an additional three-body force can noticeably alter the angular distributions at forward angles, with consequences for spectroscopic factors' studies. Additional study of transfer to $2p$ continuum in the $^{25}$F$(p,2p)^{24}$O reaction, involving the same overlap function as in the $^{24}$O($d,n)^{25}$F case, revealed that $3N$ force affects the $(d,n)$ and $(p,2p)$ reactions in a similar way, increasing the cross sections and decreasing spectroscopic factors, although its influence at the main peak of $(p,2p)$ is weaker. The angle-integrated cross sections are found to be less sensitive to the 3N force contribution, they increase by less than 20$\%$. Including 3N interactions in nucleon removal reactions makes an essential step towards bringing together nuclear structure theory, where 3N force is routinely used, and nuclear direct reaction theory, based on two-nucleon interactions only., Comment: Accepted in Physics Letters B

The discrepancy between experimental data and theoretical calculations in one-nucleon removal reactions at intermediate energies (quantified by the so-called "quenching factors") and its dependence on the isospin asymmetry of the nuclei has been an open problem in nuclear physics for the last fifteen years. In this work, we propose an explanation for this long-standing problem, which relies on the inclusion of the process of core destruction due to its interaction with the removed nucleon. To include this effect, we extend the commonly used eikonal formalism via an effective nucleon density, and apply it to a series of nucleon knockout reactions. The effect of core destruction is found to depend strongly on the binding energy of the removed nucleon, leading to a significant reduction of the cross section for deeply bound nucleons, which reduces the isospin dependence of the "quenching factors", making them more consistent with the trends found in transfer and (p,pN) reactions., Comment: 7 pages, 4 figures, Submitted to Physical Review Letters

A ray-theoretic phase space description of linear waves in a two-fluid (charges and neutrals) magnetized plasma is used to calculate analytic decay rates and mode transmission and conversion coefficients between fast and slow waves in two dimensions due to finite ion-neutral collision frequencies at arbitrary ionization fraction. This is relevant to partially ionized astrophysical plasmas, in particular solar and stellar atmospheres. The most important parameter governing collisional effects is the ratio of the wave frequency to the neutral-charges collision frequency, $\epsilon=\omega/\nu_{nc}$, with secondary dependence on ionization fraction and wave attack angle. Comparison is made to the one-fluid magnetohydrodynamic (MHD) case, and it is found that acoustic-to-acoustic and magnetic-to-magnetic transmission through the Alfv\'en-acoustic equipartition layer is decreased by a term of $\mathcal{O}(\epsilon^2)$ relative to one-fluid (infinite collision frequency), and correspondingly acoustic-to-magnetic and magnetic-to-acoustic conversion is increased. The neutral acoustic mode is shown to dissipate rapidly as $\nu_{nc}\to\infty$. Away from the mode conversion region, dissipative decay along the remaining magneto-acoustic rays scales as $\mathcal{O}(\epsilon)$ and is found to be much more effective on magnetically dominated rays compared to acoustically dominated rays. This produces a steep jump in dissipation in mode conversion regions, where the rays change character, and can produce localized heating there and beyond. Applications to the solar chromosphere are discussed., Comment: 23 pages, 8 figures, accepted for publication in Astrophys. J. Typo in Eq (8) in previous version corrected

Front-Form Hamiltonian dynamics provides a framework in which QCD's vacuum is simple and states are boost invariant. However, canonical expressions are divergent and must be regulated in order to establish well-defined eigenvalue problems. The Renormalization Group Procedure for Effective Particles (RGPEP) provides a systematic way of finding counterterms and obtaining regulated Hamiltonians. Among its achievements is the description of asymptotic freedom, with a running coupling constant defined as the coefficient in front of the three gluon-vertex operators in the regulated Hamiltonian. However, the obtained results need a deeper understanding, since the coupling exhibits a finite dependence on the regularization functions, at least at the third-order term in the perturbative expansion. Here we present a similar derivation using a different regularization scheme based on massive gluons. The procedure can be extended to incorporate contributions from virtual fermions., Comment: 7 pages, 6 figures, proceedings of ConfXV