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Ultra-faint dwarf galaxies (UFDs) are commonly found in close proximity to the Milky Way and other massive spiral galaxies. As such, their projected stellar ellipticity and extended light distributions are often thought to owe to tidal forces. In this paper, we study the projected stellar ellipticities and faint stellar outskirts of tidally isolated ultra-faints drawn from the 'Engineering Dwarfs at Galaxy Formation's Edge' (EDGE) cosmological simulation suite. Despite their tidal isolation, our simulated dwarfs exhibit a wide range of projected ellipticities (0.03 < ε < 0.85), with many possessing anisotropic extended stellar haloes that mimic tidal tails, but owe instead to late-time accretion of lower mass companions. Furthermore, we find a strong causal relationship between ellipticity and formation time of a UFD, which is robust to a wide variation in the feedback model. We show that the distribution of projected ellipticities in our suite of simulated EDGE dwarfs matches well with a sample of 19 Local Group dwarf galaxies and a sample of 11 isolated dwarf galaxies. Given ellipticity in EDGE arises from an ex-situ accretion origin, the agreement in shape indicates the ellipticities of some observed dwarfs may also originate from a non-tidal scenario. The orbital parameters of these observed dwarfs further support that they are not currently tidally disrupting. If the baryonic content in these galaxies is still tidally intact, then the same may be true for their dark matter content, making these galaxies in our Local Group pristine laboratories for testing dark matter and galaxy formation models. [ABSTRACT FROM AUTHOR]

The estimation of galaxy stellar masses depends on the assumed prior of the star-formation history (SFH) and spatial scale of the analysis (spatially resolved versus integrated scales). In this paper, we connect the prescription of the SFH in the spectral energy distribution (SED) fitting to spatially resolved scales (∼kpc) to shed light on the systematics involved when estimating stellar masses. Specifically, we fit the integrated photometry of ∼970 massive (log (M⋆/M⊙) = 9.8–11.5), intermediate redshift (z  = 0.5–2.0) galaxies with PROSPECTOR , assuming both exponentially declining tau model and flexible SFHs. We complement these fits with the results of spatially resolved SFH estimates obtained by pixel-by-pixel SED fitting, which assume tau models for individual pixels. These spatially resolved SFHs show a large diversity in shapes, which can largely be accounted for by the flexible SFHs with PROSPECTOR. The differences in the stellar masses from those two approaches are overall in good agreement (average difference of ∼0.07 dex). Contrarily, the simpler tau model SFHs typically miss the oldest episode of star formation, leading to an underestimation of the stellar mass by ∼0.3 dex. We further compare the derived global specific star-formation rate (sSFR), the mass-weighted stellar age (t50), and the star-formation time-scale (τSF) obtained from the different SFH approaches. We conclude that the spatially resolved scales within galaxies motivate a flexible SFH on global scales to account for the diversity of SFHs and counteract the effects of outshining of older stellar populations by younger ones. [ABSTRACT FROM AUTHOR]

Gravitational waves from isolated sources have eluded detection so far. The upper limit of long-lasting continuous gravitational wave emission can now probe physically motivated models with the most optimistic being strongly constrained. Naturally, one might want to relax the assumption of the gravitational wave being quasi-infinite in duration, leading to the idea of transient continuous gravitational waves. In this paper, we outline how to get transient continuous waves from magnetars (or strongly magnetized neutron stars) that exhibit glitches and/or antiglitches and apply the model to magnetar SGR 1935+2154. The toy model hypothesizes that at a glitch or antiglitch, mass is ejected from the magnetar but becomes trapped on its outward journey through the magnetosphere. Depending on the height of the trapped ejecta and the magnetic inclination angle, we are able to reproduce both glitches and antiglitches from simple angular momentum arguments. The trapped ejecta causes the magnetar to precess leading to gravitational wave emission at once and twice the magnetar's spin frequency, for a duration equal to however long the ejecta is trapped for. We find that the gravitational waves are more detectable when the magnetar is: closer, rotating faster, or has larger glitches/antiglitches. The detectability also improves when the ejecta height and magnetic inclination angle have values near their critical values, though this requires more mass to be ejected to remain consistent with the observed glitch/antiglitch. We find it unlikely that gravitational waves will be detected from SGR 1935+2154 when using the trapped ejecta model. [ABSTRACT FROM AUTHOR]

Even over relatively recent epochs, galaxies have evolved significantly in their location in the mass–metallicity plane, which must be telling us something about the latter stages of galaxy evolution. In this paper, we analyse data from the LEGA-C survey using semi-analytic spectral and photometric fitting to determine these galaxies' evolution up to their observed epoch at z ∼ 0.7. We confirm that, at z ∼ 0.7, many objects already lie on the present-day mass–metallicity relation, but with a significant tail of high-mass low-metallicity galaxies that is not seen in the nearby Universe. Similar modelling of the evolution of galaxies in the nearby MaNGA survey allows us to reconstruct their properties at z ∼ 0.7. Once selection criteria similar to those of LEGA-C are applied, we reassuringly find that the MaNGA galaxies populate the mass–metallicity plane in the same way at z ∼ 0.7. Matching the LEGA-C sample to their mass–metallicity 'twins' in MaNGA at this redshift, we can explore the likely subsequent evolution of individual LEGA-C galaxies. Galaxies already on the present-day mass–metallicity relation form few more stars and their discs fade, so they become smaller and more bulge-like. By contrast, the high-mass low-metallicity galaxies grow their discs through late star formation, and evolve rapidly to higher metallicities due to a cut-off in their wind-driven mass-loss. There are significant indications that this late cut-off is associated with the belated end of strong active galactic nucleus activity in these objects. [ABSTRACT FROM AUTHOR]

Recently discovered regular X-ray bursts known as quasi-periodic eruptions have a proposed model that suggests a tidal stripping white dwarf inspiralling into the galaxy's central black hole on an eccentric orbit. According to this model, the interaction of the stripping white dwarf with the central black hole would also emit gravitational wave signals, their detection can help explore the formation mechanism of quasi-periodic eruptions and facilitate multimessenger observations. In this paper, we investigated the horizon distance of TianQin on this type of gravitation wave signal and found it can be set to 200 Mpc. We also find that those stripping white dwarf model sources with central black hole mass within |$10^4 \!-\! 10^{5.5}\, \mathrm{M}_\odot$| are more likely to be detected by TianQin. We assessed the parameter estimation precision of TianQin on those stripping white dwarf model sources. Our result shows that, even in the worst case, TianQin can determine the central black hole mass, the white dwarf mass, the central black hole spin, and the orbital initial eccentricity with a precision of 10−2. In the optimistic case, TianQin can determine the central black hole mass and the white dwarf mass with a precision of 10−7, determine the central black hole spin with a precision of 10−5, and determine the orbital initial eccentricity with a precision of 10−8. Moreover, TianQin can determine the luminosity distance with a precision of 10−1 and determine the sky localization with a precision of 10−2–10  |$\rm deg^2$|⁠. [ABSTRACT FROM AUTHOR]

We present a new method to simultaneously and self-consistently model the mass distribution of galaxy clusters that combines constraints from strong lensing features, X-ray emission, and galaxy kinematics measurements. We are able to successfully decompose clusters into their collisionless and collisional mass components thanks to the X-ray surface brightness, as well as use the dynamics of cluster members, to obtain more accurate masses exploiting the fundamental plane of elliptical galaxies. Knowledge from all observables is included through a consistent Bayesian approach in the likelihood or in physically motivated priors. We apply this method to the galaxy cluster Abell S1063 and produce a mass model that we publicly release with this paper. The resulting mass distribution presents different ellipticities for the intra-cluster gas and the other large-scale mass components as well as deviation from elliptical symmetry in the main halo. We assess the ability of our method to recover the masses of the different elements of the cluster using a mock cluster based on a simplified version of our Abell S1063 model. Thanks to the wealth of mutliwavelength information provided by the mass model and the detected X-ray emission, we also found evidence for an ongoing merger event with gas sloshing from a smaller infalling structure into the main cluster. In agreement with previous findings, the total mass, gas profile, and gas mass fraction are all consistent with small deviations from the hydrostatic equilibrium. This new mass model for Abell S1063 is publicly available, as the lenstool extension used to construct it. [ABSTRACT FROM AUTHOR]

In this paper, we combine the Early Science radio continuum data from the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) Survey, with optical and near-infrared data and release the cross-matched catalogues. The radio data used in this work covers 0.86 deg2 of the COSMOS field, reaches a thermal noise of 1.7  μ Jy beam−1 and contains 6102 radio components. We visually inspect and cross-match the radio sample with optical and near-infrared data from the Hyper Suprime-Cam (HSC) and UltraVISTA surveys. This allows the properties of active galactic nuclei and star-forming populations of galaxies to be probed out to z ≈ 5. Additionally, we use the likelihood ratio method to automatically cross-match the radio and optical catalogues and compare this to the visually cross-matched catalogue. We find that 94 per cent of our radio source catalogue can be matched with this method, with a reliability of 95 per cent. We proceed to show that visual classification will still remain an essential process for the cross-matching of complex and extended radio sources. In the near future, the MIGHTEE survey will be expanded in area to cover a total of ∼20 deg2; thus the combination of automated and visual identification will be critical. We compare the redshift distribution of SFG and AGN to the SKADS and T-RECS simulations and find more AGN than predicted at z ∼ 1. [ABSTRACT FROM AUTHOR]

Protostellar jets and outflows are signposts of active star formation. In H  ii regions, molecular tracers like CO only reveal embedded portions of the outflow. Outside the natal cloud, outflows are dissociated, ionized, and eventually completely ablated, leaving behind only the high-density jet core. Before this process is complete, there should be a phase where the outflow is partially molecular and partially ionized. In this paper, we capture the HH 900 outflow while this process is in action. New observations from the Enhanced Resolution Imager and Spectrograph/SPIFFIER near-infrared (IR) integral field unit spectrograph using the K-middle filter (λ = 2.06–2.34 μ m) reveal H2 emission from the dissociating outflow and Br-γ tracing its ionized skin. Both lines trace the wide-angle outflow morphology but H2 only extends ∼5000 au into the H  ii region while Br-γ extends the full length of the outflow (∼12 650 au), indicating rapid dissociation of the molecules. H2 has higher velocities further from the driving source, consistent with a jet-driven outflow. Diagnostic line ratios indicate that photoexcitation, not just shocks, contributes to the excitation in the outflow. We argue that HH 900 is the first clear example of an evaporating molecular outflow and predict that a large column of neutral material that may be detectable with Atacama Large Millimeter Array accompanies the dissociating molecules. Results from this study will help guide the interpretation of near-IR images of externally irradiated jets and outflows such as those obtained with the JWST in high-mass star-forming regions where these conditions may be common. [ABSTRACT FROM AUTHOR]

This paper presents rate coefficients for transitions between rotational levels of the A-type and E-type nuclear spin modifications of methanol induced by collisions with molecular hydrogen. These rate coefficients are required for an accurate determination of methanol abundance in the interstellar medium, where local thermodynamic equilibrium conditions generally do not apply. Time-independent close-coupling quantum scattering calculations have been employed to calculate cross-sections and rate coefficients for the (de-)excitation of methanol in collisions with para - and ortho -H2. These calculations utilized a potential energy surface (PES) for the interaction of methanol with H2 recently computed by the explicitly correlated CCSD(T)-F12a coupled-cluster method that employed a correlation-consistent aug-cc-pVTZ basis. Rate coefficients for temperatures ranging from 3 to 250 K were calculated for all transitions among the first 76 rotational levels of both A-type and E-type methanol, whose energies are less than or equal to 170 K. These rate coefficients are compared with those by Rabli and Flower who carried out coupled-state calculations using a PES computed by second-order many-body perturbation theory. Simple radiative transfer calculations using the present set of rate coefficients are also reported and compared with such calculations using the rate coefficients previously computed by Rabli and Flower. [ABSTRACT FROM AUTHOR]

This is the fourth paper of our new release of the BaSTI (a Bag of Stellar Tracks and Isochrones) stellar model and isochrone library. Following the updated solar-scaled, α-enhanced, and white dwarf model libraries, we present here α-depleted ([α/Fe] = −0.2) evolutionary tracks and isochrones, suitable to study the α-depleted stars discovered in Local Group dwarf galaxies and in the Milky Way. These calculations include all improvements and updates of the solar-scaled and α-enhanced models, and span a mass range between 0.1 and 15 M⊙, and 21 metallicities between [Fe/H] = −3.20 and +0.45 with a helium-to-metal enrichment ratio Δ Y /Δ Z  = 1.31, homogeneous with the solar-scaled and α-enhanced models. The isochrones – available in several photometric filters – cover an age range between ∼20 Myr and 14.5 Gyr, including the pre-main-sequence phase. We have compared our isochrones with independent calculations of α-depleted stellar models, available for the same α-element depletion adopted in the present investigation. We have also discussed the effect of an α-depleted heavy element distribution on the bolometric corrections in different wavelength regimes. Our α-depleted evolutionary tracks and isochrones are publicly available at our BaSTI website. [ABSTRACT FROM AUTHOR]

Sodium-bearing species such as NaCl in the gas phase have been observed in an assortment of carbon-rich and oxygen-rich stellar atmospheres and interstellar environments such as the high-mass protostellar disc surrounding Orion Src1 and the proto-binary system, IRAS 16547−4247. Their detection in relatively low-temperature regions is yet to be made. In this paper, we consider the synthesis of sodium-bearing species with an emphasis on NaCl, via both gas-phase and grain-surface chemistry under assorted interstellar conditions. We also consider the chemistry leading to the gas-phase species NaH and NaOH. Two classes of numerical simulations were run: models under isothermal conditions at temperatures from 10 to 800 K with varied intervals, and three-phase warm-up models that consist of an initial isothermal collapse at 10 K, followed by a warm-up phase in which temperature rises linearly to 200 K, and finally a hot core phase. We have included reactive desorption for both models to produce gaseous NaCl, NaH, and NaOH. We found that for isothermal models over a broad parameter space, the fractional abundances of gaseous NaCl and NaOH can reach above 2 × 10−10 and approx. 1 × 10−10, respectively, are in the detection range of observational facilities such as Atacama Large Millimeter/Submillimeter Array and JWST. For warm-up models, we found that if we consider molecules to be co-desorbed with water, gaseous NaCl can have a sufficiently large abundance for detection. We then conclude that both gaseous NaCl and NaOH can be detected; however, more experiments and quantum mechanical calculations are needed to constrain the relevant reaction rates better. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence profile plays an important role in designing and operating adaptive optics (AO) systems with multiple laser guide stars. To obtain representative free atmospheric profiles and resolved ground layer profiles for future AO systems at the Subaru telescope, we are conducting the Shack–Hartmann Atmospheric tuRbulence Profiling Experiment at the Subaru Telescope project. In this project, we develop a turbulence profiler comprising two Shack–Hartmann (SH) sensors to observe a pair of bright stars through the Subaru telescope with high spatial sampling by 2 cm subapertures. We perform two analyses on the SH spot data: variance analysis on the spot scintillation for free atmospheric profiles, and on the spot slope for ground layer profiles. This paper introduces the initial results of free atmospheric profiles as well as total seeing values and wind profiles obtained by the first two engineering runs. The free atmospheric profiles reconstructed by the two independent SH sensors show good agreement. The results are also consistent with simultaneous measurements by another profiler except for turbulence strength at ∼1 km, which is explained by an overestimation problem of scintillation-based profilers. Measured total seeing values are also smaller than the simultaneous measurements, possibly due to the difference in ground layer turbulence between the two sites. The wind profiles show good consistency with the direct measurements by a rawinsonde. Through this study, we establish a method to constrain the free atmospheric profile, the total seeing, and the wind profile by analysing data from a single SH sensor with fine subapertures. [ABSTRACT FROM AUTHOR]

The statistical properties of double main sequence (MS) binaries are very important for binary evolution and binary population synthesis. To obtain these properties, we need to identify these MS binaries. In this paper, we have developed a method to differentiate single MS stars from double MS binaries from the Chinese Space Station Telescope (CSST) Survey with machine learning. This method is reliable and efficient to identify binaries with mass ratios between 0.20 and 0.80, which is independent of the mass ratio distribution. But the number of binaries identified with this method is not a good approximation to the number of binaries in the original sample due to the low detection efficiency of binaries with mass ratios smaller than 0.20 or larger than 0.80. Therefore, we have improved this point by using the detection efficiencies of our method and an empirical mass ratio distribution and then can infer the binary fraction in the sample. Once the CSST data are available, we can identify MS binaries with our trained multi-layer perceptron model and derive the binary fraction of the sample. [ABSTRACT FROM AUTHOR]

The magneto-rotational instability (MRI), which is due to an interplay between a sheared background and the magnetic field, is commonly considered a key ingredient for developing and sustaining turbulence in the outer envelope of binary neutron star merger remnants. To assess whether (or not) the instability is active and resolved, criteria originally derived in the accretion disc literature, thus exploiting the symmetries of such systems, are often used. In this paper, we discuss the magneto-shear instability as a truly local phenomenon, relaxing common symmetry assumptions on the background on top of which the instability grows. This makes the discussion well suited for highly dynamical environments such as binary mergers. We find that, although this is somewhat hidden in the usual derivation of the MRI dispersion relation, the instability crucially depends on the assumed symmetries. Relaxing the symmetry assumptions in the background, we find that the role of the magnetic field is significantly diminished, as it affects the modes' growth but does not drive it. We conclude by making contact with a suitable filtering operation, as this is key to separating background and fluctuations in highly dynamical systems. [ABSTRACT FROM AUTHOR]

Measurements of the dependence of stellar specific angular momentum (j *) on stellar mass (M *) are presented for large samples of galaxies from the Arecibo Legacy Fast ALFA (ALFALFA) survey, spanning the stellar mass range ∼108–1011 M⊙. Accurate estimates of j * are generated using measurements of I -band effective radius and velocity width of the H  i line profile. While the full sample (N = 3607) of galaxies yields a j *– M * relation with power-law index α = 0.404 ± 0.03, it is shown that various subsamples have indices that are very similar to the best literature results, yet with comparatively lower intrinsic scatters. A galaxy's mean I -band surface brightness within its effective radius (<μeff>) is shown to significantly correlate with j *– M * scatter. A 3D plane fit to all N = 3607 galaxies in log10 j *–log10 M *–<μeff> space yields j * ∝ M 0.589 ± 0.002 <μeff>0.193 ± 0.002 with scatter σ = 0.089 dex. <μeff>-selected subsamples of size up to N = 1450 yield power-law j *– M * relations mostly consistent with α = 0.55 ± 0.02 from the literature and with intrinsic scatter ranging from 0.083 to 0.129 dex. Thus, this paper presents new, highly accurate measurements of the j *– M * relation that can be used to better understand the important roles played by angular momentum in the formation and evolution of galaxies. [ABSTRACT FROM AUTHOR]

Fast radio bursts (FRBs) are millisecond radio signals from cosmological distances. As they propagate, FRBs can interact with ambient photons and initiate a quantum cascade that can limit the electric field strength. This paper examines whether some observed bright and brief FRBs may challenge this limit if the source is not relativistic. The size of a static FRB source is estimated as R ∼ ct , where t is the time-scale of the FRB and c denotes the speed of light. But for a relativistic source moving at the Lorentz factor Γ, the size is R ∼ 2Γ2 ct. Using an FRB catalogue, we plot the luminosity–duration distribution. Most FRBs fall below the limit for a static source, but two events have higher luminosity and shorter duration. This suggests these bursts may originate from relativistic sources, although more data are needed to confirm this. [ABSTRACT FROM AUTHOR]

The paper presents the analysis of optically selected GAMA groups and clusters in the SRG/eROSITA X-ray map of eROSITA Final Equatorial Depth Survey, in the halo mass range 1013−5 × 1014 M⊙ and at z < 0.2. All X-ray detections have a clear GAMA counterpart, but most of the GAMA groups in the halo mass range 1013−1014 M⊙ remain undetected. We compare the X-ray surface brightness profiles of the eROSITA detected groups with the mean stacked profile of the undetected low-mass haloes at fixed halo mass. Overall, we find that the undetected groups exhibit less concentrated X-ray surface brightness, dark matter, and galaxy distributions with respect to the X-ray-detected haloes. The mean gas mass fraction profiles are consistent in the two samples within 1.5σ, indicating that the gas follows the dark matter profile. The low-mass concentration and the magnitude gap indicate that these systems are young. They reside with a higher probability in filaments while X-ray-detected groups favour the nodes of the Cosmic Web. Because of the lower central emission, the undetected systems tend to be X-ray underluminous at fixed halo mass and to lie below the LX − M halo relation. Interestingly, the X-ray-detected systems inhabiting the nodes scatter the less around the relation, while those in filaments tend to lie below it. We do not observe any strong relationship between the system X-ray appearance and the active galactic nucleus (AGN) activity. We cannot exclude the role of the past AGN feedback in affecting the gas distribution over the halo lifetime. However, the data suggests that the observed differences might be related to the halo assembly bias. [ABSTRACT FROM AUTHOR]

In this paper, we perform a dynamical study of the population of objects in the unstable quasi-Hilda region. The aim of this work is to make an update of the population of quasi-Hilda comets (QHCs) that have recently arrived from the Centaurs region. To achieve our goal, we have applied a dynamical criteria to constrain the unstable quasi-Hilda region that allowed us to select 828 potential candidates. The orbital data of the potential candidates were taken from the ASTORB data base and we apply backward integration to search by those that have recently arrived from the outer regions of the Solar system. Then we studied the dynamical evolution of the candidates from a statistical point of view by calculating the time-averaged distribution of a number of clones of each candidate as a function of aphelion and perihelion distances. We found that 47 objects could have been recently injected into the inner Solar system from the Centaur or transneptunian regions. These objects may have preserved volatile material and are candidates to exhibit cometary activity. [ABSTRACT FROM AUTHOR]

Measurements of the peculiar velocities of large samples of galaxies enable new tests of the standard cosmological model, including determination of the growth rate of cosmic structure that encodes gravitational physics. With the size of such samples now approaching hundreds of thousands of galaxies, complex statistical analysis techniques and models are required to extract cosmological information. In this paper, we summarize how correlation functions between galaxy velocities, and with the surrounding large-scale structure, may be utilized to test cosmological models. We present new determinations of the analytical covariance between such correlation functions, which may be useful for cosmological likelihood analyses. The statistical model we use to determine these covariances includes the sample selection functions, observational noise, curved-sky effects, and redshift-space distortions. By comparing these covariance determinations with corresponding estimates from large suites of cosmological simulations, we demonstrate that these analytical models recover the key features of the covariance between different statistics and separations, and produce similar measurements of the growth rate of structure. [ABSTRACT FROM AUTHOR]

The theory of nested figures of equilibrium, expanded in Papers I and II, is investigated in the limit where the number of layers of the rotating body is infinite, enabling to reach full heterogeneity. In the asymptotic process, the discrete set of equations becomes a differential equation for the rotation rate. In the special case of rigid rotation (from centre to surface), we are led to an integro-differential equation (IDE) linking the ellipticity of isopycnic surfaces to the equatorial mass-density profile. In contrast with most studies, these equations are not restricted to small flattenings, but are valid for fast rotators as well. We use numerical solutions obtained from the self-consistent-field method to validate this approach. At small ellipticities (slow rotation), we fully recover Clairaut's equation. Comparisons with Chandrasekhar's perturbative approach and with Roberts' work based on virial equations are successful. We derive a criterion to characterize the transition from slow to fast rotators. The treatment of heterogeneous structures containing mass-density jumps is proposed through a modified IDE. [ABSTRACT FROM AUTHOR]

We present the measurement of total and stellar/dark matter decomposed mass density profile around a sample of galaxy groups and clusters with dynamical masses derived from integral-field stellar kinematics from the MaNGA survey in Paper I and weak lensing derived from the DECaLS imaging survey. Combining the two data sets enables accurate measurement of the radial density distribution from several kpc to Mpc scales. Intriguingly, we find that the excess surface density derived from stellar kinematics in the inner region cannot be explained by simply adding an NFW dark matter halo extrapolated from lensing measurement at a larger scale to a stellar mass component derived from the NASA-Sloan Atlas (NSA) catalogue. We find that a good fit to both data sets requires a stellar mass normalization about three times higher than that derived from the NSA catalogue, which would require an unrealistically too-heavy initial mass function for stellar mass estimation. If we keep the stellar mass normalization to that of the NSA catalogue but allow a varying inner dark matter density profile, we obtain an asymptotic slope of γgnfw =  |$1.82_{-0.25}^{+0.15}$| and γgnfw =  |$1.48_{-0.41}^{+0.20}$| for the group bin and the cluster bin, respectively, significantly steeper than the NFW case. We also compare the total mass inner density slopes with those from TNG300 and find that the values from the simulation are lower than the observation by about 2σ level. [ABSTRACT FROM AUTHOR]

The recent discovery of multiple planets in the circumbinary system TOI-1338/BEBOP-1 raises questions about how such a system formed. The formation of the system was briefly explored in the discovery paper, but only to answer the question do current pebble accretion models have the potential to explain the origin of the system? We use a global model of circumbinary planet formation that utilizes N -body simulations, including prescriptions for planet migration, gas and pebble accretion, and interactions with a circumbinary disc, to explore the disc parameters that could have led to the formation of the TOI-1338/BEBOP-1 system. With the disc lifetime being the main factor in determining how planets form, we limit our parameter space to those that determine the disc lifetime. These are: the strength of turbulence in the disc, the initial disc mass, and the strength of the external radiation field that launches photoevaporative winds. When comparing the simulated systems to TOI-1338/BEBOP-1, we find that only discs with low levels of turbulence are able to produce similar systems. The radiation environment has a large effect on the types of planetary systems that form, whilst the initial disc mass only has limited impact since the majority of planetary growth occurs early in the disc lifetime. With the most TOI-1338/BEBOP-1 like systems all occupying similar regions of parameter space, our study shows that observed circumbinary planetary systems can potentially constrain the properties of planet forming discs. [ABSTRACT FROM AUTHOR]

Analysis of f-mode frequencies has provided a measure of the radius of the Sun which is lower, by a few hundredths per cent, than the photospheric radius determined by direct optical measurement. Part of this difference can be understood by recognizing that it is primarily the variation of density well beneath the photosphere of the star that determines the structure of these essentially adiabatic oscillation modes, not some aspect of radiative intensity. In this paper we attempt to shed further light on the matter, by considering a differently defined, and dynamically more robust, seismic radius, namely one determined from p-mode frequencies. This radius is calibrated by the distance from the centre of the Sun to the position in the subphotospheric layers where the first derivative of the density scale height changes essentially discontinuously. We find that radius is more-or-less consistent with what is suggested by the f modes. In addition, the interpretation of the radius inferred from p modes leads us to understand more deeply the role of the total mass constraint in the structure inversions. This enables us to reinterpret the sound-speed inversion, suggesting that the positions of the photosphere and the adiabatically stratified layers in the convective envelope differ non-homologously from those of the standard solar model. [ABSTRACT FROM AUTHOR]

Interstellar aromatic molecules such as polycyclic aromatic hydrocarbons and polycyclic nitrogen and oxygen bearing molecules are thought to be abundant in the interstellar medium (ISM). In this class of molecules, benzonitrile (c-C6H5CN) plays an important role as a proxy for benzene. It has been detected through rotational emission in several astrophysical sources and is one of the simplest N-bearing polar aromatic molecules. Even in the cold ISM, the population of the rotational levels of benzonitrile might not be at equilibrium. Consequently, modelling its detected emission lines requires a prior computation of its quenching rate coefficients by the most abundant species in the ISM (He or H2). In this paper, we focus on the excitation of c-C6H5CN by collision with He. We compute the first potential energy surface (PES) using the explicitly correlated coupled cluster method in conjunction with large basis sets. The PES obtained is characterized by a potential well depth of −97.2 cm−1 and an important anisotropy. Scattering computations of the rotational (de-)excitation of c-C6H5CN by He atoms are performed by means of the coupled states approximation that allow to obtain collisional rates for rotational states up to j  = 9 and temperatures up to 40 K. These rate coefficients are then used to examine the effect of C6H5CN excitation induced by collisions with para-H2 in molecular clouds by carrying out simple radiative transfer calculations of the excitation temperatures and show that non-equilibrium effects can be expected for H2 densities up to 105–106 cm−3. [ABSTRACT FROM AUTHOR]

Arkenstone is a new model for multiphase, stellar feedback-driven galactic winds designed for inclusion in coarse resolution cosmological simulations. In this first paper of a series, we describe the features that allow Arkenstone to properly treat high specific energy wind components and demonstrate them using idealized non-cosmological simulations of a galaxy with a realistic circumgalactic medium (CGM), using the arepo code. Hot, fast gas phases with low mass loadings are predicted to dominate the energy content of multiphase outflows. In order to treat the huge dynamic range of spatial scales involved in cosmological galaxy formation at feasible computational expense, cosmological volume simulations typically employ a Lagrangian code or else use adaptive mesh refinement with a quasi-Lagrangian refinement strategy. However, it is difficult to inject a high specific energy wind in a Lagrangian scheme without incurring artificial burstiness. Additionally, the low densities inherent to this type of flow result in poor spatial resolution. Arkenstone addresses these issues with a novel scheme for coupling energy into the transition region between the interstellar medium (ISM) and the CGM, while also providing refinement at the base of the wind. Without our improvements, we show that poor spatial resolution near the sonic point of a hot, fast outflow leads to an underestimation of gas acceleration as the wind propagates. We explore the different mechanisms by which low and high specific energy winds can regulate the star formation rate of galaxies. In future work, we will demonstrate other aspects of the Arkenstone model. [ABSTRACT FROM AUTHOR]

Direct imaging is an active research topic in astronomy for the detection and the characterization of young substellar objects. The very high contrast between the host star and its companions makes the observations particularly challenging. In this context, post-processing methods combining several images recorded with the pupil tracking mode of telescope are needed. In previous works, we have presented a data-driven algorithm, PACO , capturing locally the spatial correlations of the data with a multivariate Gaussian model. PACO delivers better detection sensitivity and confidence than the standard post-processing methods of the field. However, there is room for improvement due to the approximate fidelity of the PACO statistical model to the time evolving observations. In this paper, we propose to combine the statistical model of PACO with supervised deep learning. The data are first pre-processed with the PACO framework to improve the stationarity and the contrast. A convolutional neural network (CNN) is then trained in a supervised fashion to detect the residual signature of synthetic sources. Finally, the trained network delivers a detection map. The photometry of detected sources is estimated by a second CNN. We apply the proposed approach to several data sets from the VLT/SPHERE instrument. Our results show that its detection stage performs significantly better than baseline methods (cADI and PCA), and leads to a contrast improvement up to half a magnitude compared to PACO. The characterization stage of the proposed method performs on average on par with or better than the comparative algorithms (PCA and PACO) for angular separation above 0.5 arcsec. [ABSTRACT FROM AUTHOR]

The theory of line-driven winds can explain many observed spectral features in early-type stars, though our understanding the winds of B supergiants remains incomplete. The hydrodynamic equations for slowly rotating stellar winds predict two regimes based on the line-force parameter δ: the fast and the δ- slow solution. In this paper, we aim to explore the capability of the latter to explain the observed properties of B supergiant winds. We calculate Hα line profiles, the most sensitive wind diagnostics in the optical, for both fast and δ- slow wind models. We fit them to observed data from a well-studied sample of B supergiants, by adapting the line-force parameters (k , α, and δ) of the hydrodynamic model. Unexpectedly, the observed Hα spectra can be reproduced by both hydrodynamic wind regimes with similar precision. We argue that this similarity results from the similar shape of the normalized velocity law produced by both regimes in the lower, Hα-forming wind region. Our findings raise a dichotomy, because mass-loss rates and terminal velocities (v ∞) for each solution are quite different. The δ- slow solution predicts maximum values for v ∞ that are systematically lower than those measured in the ultraviolet, whereas the v ∞ values of the fast solution are closer, and probably more appropriate. However, our results also indicate that the δ- slow solution might better describe the dense winds of B hypergiants. Multiwavelength analyses and a larger sample of stars are needed to reach a definitive conclusion. [ABSTRACT FROM AUTHOR]

Currently, astrometric microlensing is the only tool that can directly measure the mass of a single star; it can also help us to detect compact objects such as isolated neutron stars and black holes. The number of microlensing events that are being predicted and reported is increasing. In this paper, potential lens stars are selected from three types of stars: high-proper-motion stars, nearby stars, and high-mass stars. For each potential lens star, we select a larger search scope to find possible matching sources and to avoid missing events as much as possible. Using data from Gaia Data Release 3, we predict 4500 astrometric microlensing events with δθ+ > 0.1 mas, which occur between J2010.0 and J2070.0, where 1664 events are different from those found previously. There are 293 lens stars that can cause two or more events, where five lens stars can cause more than 50 events. We find that 116 events have the distance of background stars from the proper motion path of lens stars more than 8 arcsec in the reference epoch, where the maximum distance is 16 |${_{.}^{\prime\prime}}$| 6. Thus, the cone search method of expanding the search range of sources for each potential lens star can reduce the possibility of missing events. [ABSTRACT FROM AUTHOR]

The point-spread function (PSF) is a fundamental property of any astronomical instrument. In interferometers, differing array configurations combined with their uv coverage, and various weighting schemes can produce an irregular but deterministic PSF. As a result, the PSF is often deconvolved using CLEAN-style algorithms to improve image fidelity. In this paper, we revisit a significant effect that causes the flux densities measured with any interferometer to be systematically offset from the true values. Using a suite of carefully controlled simulations, we show that the systematic offset originates from a mismatch in the units of the image produced by these CLEAN-style algorithms. We illustrate that this systematic error can be significant, ranging from a few to tens of per cent. Accounting for this effect is important for current and future interferometric arrays, such as MeerKAT, LOFAR, and the SKA, whose core-dominated configuration naturally causes an irregular PSF. We show that this offset is independent of other systematics, and can worsen due to some factors such as the goodness of the fit to the PSF, the deconvolution depth, and the signal-to-noise ratio of the source. Finally, we present several methods that can reduce this effect to just a few per cent. [ABSTRACT FROM AUTHOR]

Atmospheric characterization of exoplanets from the ground is an actively growing field of research. In this context, we have created the ATMOSPHERIX consortium: a research project aimed at characterizing exoplanets atmospheres using ground-based high-resolution spectroscopy. This paper presents the publicly available data analysis pipeline and demonstrates the robustness of the recovered planetary parameters from synthetic data. Simulating planetary transits using synthetic transmission spectra of a hot Jupiter that were injected into real SPIRou observations of the non-transiting system Gl 15 A, we show that our pipeline is successful at recovering the planetary signal and input atmospheric parameters. We also introduce a deep learning algorithm to optimize data reduction which proves to be a reliable, alternative tool to the commonly used principal component analysis. We estimate the level of uncertainties and possible biases when retrieving parameters such as temperature and composition and hence the level of confidence in the case of retrieval from real data. Finally, we apply our pipeline onto two real transits of HD 189733 b observed with SPIRou and obtain similar results than in the literature. In summary, we have developed a publicly available and robust pipeline for the forthcoming studies of the targets to be observed in the framework of the ATMOSPHERIX consortium, which can easily be adapted to other high resolution instruments than SPIRou (e.g. VLT-CRIRES, MAROON-X, ELT-ANDES). [ABSTRACT FROM AUTHOR]

This document is a correction to a previous article titled "3D simulations of photochemical hazes in the atmosphere of hot Jupiter HD 189733b." The correction addresses two errors in equation (7) of the original paper, specifically the sign of a term and the prefactor in front of the curly brackets. These errors occurred during the transfer of equations from handwritten notes to the manuscript. The correction clarifies that the python code used for the analysis in section 4 of the paper used the correct version of the equations, and none of the other results in the paper are affected by these errors. The correction is authored by Maria E Steinrueck, Adam P Showman, Panayotis Lavvas, Tommi Koskinen, Xianyu Tan, and Xi Zhang. [Extracted from the article]

This document is a correction to a previously published paper titled "Why the observed spin evolution of older-than-solar-like stars might not require a dynamo mode change." The correction addresses minor typographical errors that do not impact the results of the paper but could cause confusion in reproducing the calculations. Specifically, the correction involves changing the notation for stellar mass and radius in subsection 2.3. The corrected notation uses m⊙* and r⊙* to represent normalized values to solar mass and solar radius. The authors of the paper are Ketevan Kotorashvili, Eric G Blackman, and James E Owen. [Extracted from the article]

This article is a correction to a previous paper on the collisional rate coefficients for H3O+ - H2 interactions in warm interstellar clouds. The authors discovered errors in the supplementary material of their previous paper, which were caused by a software bug in the calculations of high energy cross sections. The corrections made to the data have a minor impact on the rate coefficients at lower temperatures, but some specific transitions are significantly affected at higher temperatures. However, these corrections do not change the overall conclusions of the original paper. The corrected data is available in the supplementary material and through various databases. [Extracted from the article]

This is a correction to: E M Broadbent, R A Phillipson, Correlated spectral and recurrence variations of Cygnus X-1, Monthly Notices of the Royal Astronomical Society, Volume 527, Issue 3, January 2024, Pages 7794–7809, https://doi.org/10.1093/mnras/stad3671.In the originally published version of this paper the corresponding author and email information was incorrect. R. A. Phillipson is the corresponding author and rebecca.phillipson@villanova.edu the correct email address.This error has been corrected in the original paper. [Extracted from the article]

This document is a correction to a previously published paper titled "GMRT observations of the radio trail from CXOU J163802.6 − 471358." The correction addresses errors in the resolutions of the GMRT images provided in the caption of Figure 1 and in Section 2 of the paper. The correct resolutions at 1387.5 MHz are 6.0 × 3.1 arcsec2 at a position angle of 24○, and at 322.8 MHz they are 16.5 × 8.0 arcsec2 at a position angle of 8○. The correction does not impact the conclusions of the paper. [Extracted from the article]

This document is a correction to a previous paper published in the Monthly Notices of the Royal Astronomical Society. The original paper contained incorrect values in table 1, which could lead to incorrect results if used to correct Gaia DR2 data for extinction. The correct values, based on a grid of Kurucz model spectra, the extinction law of Fitzpatrick et al., and the revised Gaia DR2 photometric passbands, have been made available. The authors confirm that the conclusions of the original paper remain unchanged. [Extracted from the article]

The article titled "Correction to: Redshift drift and strong gravitational lensing" acknowledges a mistake made in a recent paper by the author. The mistake relates to the measurement of the Hubble constant using the difference in redshift between images of a gravitational-lens system. The author clarifies that the redshift difference can still be used to measure other cosmological parameters without knowledge of the Hubble constant. The rest of the paper remains unaffected, discussing various aspects of standard cosmology and gravitational lensing. No new data is associated with the article. [Extracted from the article]

This document is a correction to a paper titled "The formation of early-type galaxies through monolithic collapse of gas clouds in Milgromian gravity." The correction addresses an error in equation (8) on page 1083 of the paper. The error does not affect the results or conclusions of the study, but it is important to use the correct equation in future studies to avoid mistakes. The correct equation is provided in the document. The authors of the paper are Robin Eappen, Pavel Kroupa, Nils Wittenburg, Moritz Haslbauer, and Benoit Famaey. [Extracted from the article]

This document is a correction to a paper titled "Fundamental scales in the kinematic phase of the turbulent dynamo" published in the Monthly Notices of the Royal Astronomical Society. The correction addresses a typo in section 2.1 of the paper, specifically in the description of the traceless rate of strain tensor. The correct tensor is provided, and it is stated that the error only affected the reporting in the paper, not the results or conclusions of the study. [Extracted from the article]

This document is a correction to a paper titled "X-ray surface brightness and gas density profiles of galaxy clusters up to 3 × R500c with SRG/eROSITA." The correction addresses several typos in the description of equation (C1) in the appendix, which could be misleading. The correction provides the correct lines for the equation and includes the best-fitting values of the parameters. The authors acknowledge Andrew Sullivan for bringing this issue to their attention. [Extracted from the article]

This is a correction to: Pawan Kumar, Bidya Binay Karak, Anu Sreedevi, Variabilities in the polar field and solar cycle due to irregular properties of bipolar magnetic regions, Monthly Notices of the Royal Astronomical Society, Volume 530, Issue 3, May 2024, Pages 2895–2905, https://doi.org/10.1093/mnras/stae1052.In the originally published version of the manuscript, there was a typographical error in the last word of the paper's title. This now reads: '[...] regions' instead of: '[...] suregions'. [Extracted from the article]

This document is a correction to a previous publication titled "Hyperbolic conduction: A fast, physical conduction model implemented in Smoothed Particle Hydrodynamics." The original publication contained errors in equations (8) and (10), which have now been corrected. Additionally, a typographical error in the fourth paragraph of section 3.1 has been fixed. These corrections do not affect the conclusions of the paper. The authors are N. A. Owens and J. Wadsley. [Extracted from the article]

This is a correction to: Ruiqi Sun, Yushan Li, Quentin Parker, Jiaxin Li, Xu Li, Liang Cao, Peng Jia, Artificial Intelligence Techniques for Uncovering Resolved Planetary Nebula Candidates from Wide-field VPHAS+ Survey Data, Monthly Notices of the Royal Astronomical Society, Volume 528, Issue 3, March 2024, Pages 4733–4745, https://doi.org/10.1093/mnras/stad3954.Since the originally published version of this paper, the authors Quentin Parker and Peng Jia have been added as co-corresponding authors alongside Yushan Li. [Extracted from the article]

This document is a correction to a paper titled "Wave modes and instabilities in gravitating magnetized polytropic quantum plasmas including viscosity tensor and FLR corrections." The original publication contained typographical errors in several equations, where the divergence operator was mistakenly replaced by the curl operator. This correction provides the correct forms of the equations. The corrected equations are provided in the document. [Extracted from the article]

This document is a correction to a paper titled "Precision Ephemerides for Gravitational-wave Searches – IV. Corrected and refined ephemeris for Scorpius X-1" published in the Monthly Notices of the Royal Astronomical Society. The correction addresses a typographical error in table 2, where the uncertainty on the orbital period was incorrectly stated. The corrected version of the table has been updated online. The correction does not affect the published chains, which remain the authoritative source of parameters. The document also includes a table presenting posterior distribution summary statistics for the ephemeris. [Extracted from the article]