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We introduce the Serendipitous H-ATLAS-fields Observations of Radio Extragalactic Sources (SHORES) multiple pencil beam survey that observed at 2.1 GHz with the Australia Telescope Compact Array (ATCA) 29 fields in total intensity and polarization within the Herschel-ATLAS Southern Galactic Field. This paper presents the observations, calibration and analysis of the 27 shallow fields that cover an overall area of $\sim 26$ square degree with increasing sensitivity towards the phase centers of each pointing according to the ATCA 22 m dish response function, down to $\sigma\lesssim 33\, \mu$Jy. Two additional (deep) fields have been observed to even higher sensitivity. All the SHORES observations have been calibrated to account also for linear polarization. Polarization and deeper field analysis will be presented in future papers. The SHORES shallow-field sample considered in the present paper counts $2294$ sources detected with BLOBCAT to signal-to-noise ratio $SNR\gtrsim 4.5$. Simulations determined that our procedure and final catalog is 95% reliable above $497.5\, \mu$Jy and $95\%$ complete to the $SNR\gtrsim 4.5$ significance level. By exploiting ATCA E-W 6 km configuration we reached resolutions of $3.2\times 7.2$ arcsec, to which level $81\%$ of our sources are unresolved. We determined source counts down to the $150\, \mu$Jy level. For the sources with a counterpart in H-ATLAS, the FIR-radio correlation is calculated and discussed., Comment: 30 pages, 23 figures. Accepted on PASP. Project website at the URL: https://sites.google.com/inaf.it/shores

We consider projective Hyper-K\"ahler manifolds of dimension four that are deformation equivalent to Hilbert squares of K3 surfaces. In case such a manifold admits a divisorial contraction, the exceptional divisor is a conic bundle over a K3 surface. There are five types of such conic bundles. In case the manifold has Picard rank two and has two (birational) divisorial contractions we determine the types of these conic bundles. There are exactly seven cases. For the Fano varieties of cubic fourfolds there are only four cases and we provide examples of these., Comment: 19 pages

We provide comments on article "Fundamental nature of the self-field critical current in superconductors" by Talantsev and Tallon, arXiv:2409.16758 and https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4978589 related to the predictions of the key equation proposed in article "Universal self-field critical current for thin-film superconductors," by Talantsev and Tallon, Nat. Commun. 6 (2015) 7820. We respond to claims and assertions made in these articles and also show that the so-called "Universal self-field critical current" and the "fundamental limit" for self-field Jc suggested by Talantsev and Tallon, has been proven incorrect experimentally and this invalidates the key claims and findings stated in both these articles., Comment: 6 pages

We provide comments on article titled "Procedures for proper validation of record critical current density claims" by Chiara Tarantini and David C. Larbalestier, arXiv:2410.22195. We respond to claims and assertions that the expressions for calculation of $J_{c,mag}$ from magnetic moments proposed in Polichetti et al. 2024, arXiv:2410.09197, are incorrect. We show that the analysis presented in Tarantini and Larbalestier is wrong. We also re-emphasize the expression presented in Polichetti et al. for calculation of $J_{c,mag}$ from magnetic moments in which the pre-factor is dimensionless and has NO units. We make the case for establishment of national user facilities for measurement of transport $J_c(H,T,\theta)$ that are easily accessible in an equitable and rapid manner to enable much needed advances in the field., Comment: Reply to arXiv:2410.22195, which is a comment on arXiv:2410.09197

This study analyzes the calculation of the critical current density Jc,mag by means of Bean's critical state model, using the equation formulated by Gyorgy et al. and other similar equations derived from it reported in the literature. While estimations of Jc,mag using Bean's model are widely performed, improper use of different equations with different magnetic units and pre-factors leads to confusion and to significant errors in the reported values of Jc,mag. In this work, a SINGLE general equation is proposed for the calculation of Jc,mag for a rectangular parallelepiped sample in perpendicular field using Bean's critical state model, underlying how the simple conversion of magnetic units can lead to a Jc,mag in the desired units, without the need to introduce any other correction or use other specific equations depending on the units of Jc,mag. In this equation, the numerical pre-factor is dimensionless, independent of the unit system used. A comparison between the expression reported in the literature is done, showing how they can lead to different results depending on the used units, and that these results can be at least one order of magnitude different from the correct results obtained with the general equation proposed in this work. This resolves all ambiguities and aligns with the correct dimensional analysis, eliminates discrepancies in the calculated Jc,mag, and will avoid further propagation of errors in the literature., Comment: This replaced version has a new title, includes the first version of arXiv:2410.09197 ("Expression with self-consistent magnetic units for calculation of critical current density using the Bean's Model" submitted on 11 Oct 2024) and the following paper arXiv:2411.16685, is enriched with additional cases, and has been published on Materials 2025, 18, 269 - https://doi.org/10.3390/ma18020269

An element in the Brauer group of a general complex projective $K3$ surface $S$ defines a sublattice of the transcendental lattice of $S$. We consider those elements of prime order for which this sublattice is Hodge-isometric to the transcendental lattice of another K3 surface $X$. We recall that this defines a finite map between moduli spaces of polarized K3 surfaces and we compute its degree. We show how the Picard lattice of $X$ determines the Picard lattice of $S$ in the case that the Picard number of $X$ is two., Comment: 16 pages, submitted to Rendiconti Semin. Mat. Univ.Politecn. Torino, volume dedicated to the memory of Gianfranco Casnati

In this paper, we investigate the benefits of teaming up data from the radio to the far- 1 infrared (FIR) regime for the characterization of Dusty Star-Forming Galaxies (DSFGs). These galaxies 2 are thought to be the star-forming progenitors of local massive quiescent galaxies, and play a pivotal 3 role in the reconstruction of the cosmic star formation rate density up to high redshift. Due to their 4 dust-enshrouded nature, DSFGs are often invisible in the near-infrared/Optical/UV bands. Therefore, 5 they necessitate observations at longer wavelengths, primarily the FIR, where dust emission occurs, 6 and radio, which is not affected by dust absorption. Combining data from these two spectral windows 7 makes it possible to characterize even the dustiest objects, enabling the retrieval of information about 8 their age, dust temperature, and star-formation status, and facilitates the differentiation between 9 various galaxy populations that evolve throughout cosmic history. Despite the detection of faint radio 10 sources being a challenging task, this study demonstrates that an effective strategy to build statistically 11 relevant samples of DSFGs would be reaching deep sensitivities in the radio band, even restricted to 12 smaller areas, and then combining these radio observations with FIR/submm data. Additionally, 13 the paper quantifies the improvement in the Spectral Energy Distribution (SED) reconstruction of 14 DSFGs by incorporating ALMA band measurements, in particular, in its upgraded status thanks to 15 the anticipated Wideband Sensitivity Upgrade.

A specialization of a K3 surface with Picard rank one to a K3 with rank two defines a vanishing class of order two in the Brauer group of the general K3 surface. We give the B-field invariants of this class. We apply this to the K3 double plane defined by a cubic fourfold with a plane. The specialization of such a cubic fourfold whose group of codimension two cycles has rank two to one which has rank three induces such a specialization of the double planes. We determine the Picard lattice of the specialized double plane as well as the vanishing Brauer class and its relation to the natural "Clifford" Brauer class. This provides more insight in the specializations. It allows us to explicitly determine the K3 surfaces associated to infinitely many of the conjecturally rational cubic fourfolds obtained as such specializations., Comment: 18 pages. The proof of the main result is simplified

Let S be a site. We show that the 2-stack of strictly commutative Picard stacks over S is algebraic, i.e. it is 2-equivalent to the 2-stack of 2-algebras for an adequate algebraic 2-stack theory over S.

We report ALMA high-resolution observations of water emission lines $p-{\rm{H_2O}} (2_{02}-1_{11}$), $o-{\rm{H_2O}} (3_{21}-3_{12})$, $p-{\rm{H_2O}} (4_{22}-4_{13})$, in the strongly lensed galaxy HATLASJ113526.2-01460 at redshift z $\sim$ 3.1. From the lensing-reconstructed maps of water emission and line profiles, we infer the general physical properties of the ISM in the molecular clouds where the lines arise. We find that the water vapor lines $o-{\rm{H_2O}} (3_{21}-3_{12})$, $p-{\rm{H_2O}} (4_{22}-4_{13})$ are mainly excited by FIR pumping from dust radiation in a warm and dense environment, with dust temperatures ranging from 70 K to $\sim 100$ K, as suggested by the line ratios. The $p-{\rm{H_2O}} (2_{02}-1_{11})$ line instead, is excited by a complex interplay between FIR pumping and collisional excitation in the dense core of the star-forming region. This scenario is also supported by the detection of the medium-level excitation of CO resulting in the line emission CO (J=8-7). Thanks to the unprecedented high resolution offered by the combination of ALMA capabilities and gravitational lensing, we discern the different phases of the ISM and locate the hot molecular clouds into a physical scale of $\sim$ 500 pc. We discuss the possibility of J1135 hosting an AGN in its accretion phase. Finally, we determine the relation between the water emission lines and the total IR luminosity of J1135, as well as the SFR as a function of water emission intensities, comparing the outcomes to local and high-$z$ galactic samples from the literature., Comment: 22 pages, 10 figures, final version to be published in Astrophysical Journal

The \textit{Herschel} Astrophysical Terahertz Large Area Survey (H-ATLAS), that has covered about 642 sq. deg. in 5 bands from 100 to 500 $\mu\rm m$, allows a blind flux-limited selection of blazars at sub-mm wavelengths. However, blazars constitute a tiny fraction of H-ATLAS sources and therefore identifying them is not a trivial task. Using the data on known blazars detected by the H-ATLAS we have defined a locus for 500\,$\mu$m selected blazars and exploited it to select blazar candidates in the H-ATLAS fields. Candidates and known blazars in the H-ATLAS equatorial and South Galactic Pole fields were followed up with the Australia Telescope Compact Array (ATCA) or with the Karl G. Jansky Very Large Array (VLA), and matched with existing radio- and mm-catalogues to reconstruct the spectral behaviour over at least 6 orders of magnitude in frequency. We identified a selection approach that, combining the information in the sub-mm and radio domains, efficiently singles out genuine blazars. In this way, we identified a sample of 39 blazars brighter than $S_{500\mu\rm m} = 35\,$mJy in the H-ATLAS fields. Tests made cross-matching the H-ATLAS catalogues with large catalogues of blazar candidates indicate that the sample is complete. The derived counts are compared with model predictions finding good consistency with the C2Ex model and with estimates based on ALMA data., Comment: 16 pages, 7 figures, accepted by MNRAS

The link between the surface temperature of Mercury and the exosphere sodium content has been investigated. Observations show that, along the orbit of Mercury, two maxima of total Na content are present: one at aphelion and one at perihelion. Previous models, based on a simple thermal map, were not able to reproduce the aphelion peak. Here we introduce a new thermophysical model giving soil temperatures as an input for the IAPS exospheric model already used in the past with the input of a simple thermal map. By comparing the reference model output with the new one, we show that such improved surface temperature map is crucial to explain the temporal variability of Sodium along the orbit.

The Planck sub-mm surveys detected the brightest strongly gravitationally lensed dusty galaxies in the sky. The combination of their extreme gravitational flux boosting and image stretching offers the unique possibility of measuring in detail, via high-resolution imaging and spectroscopic follow-up, the galaxy structure and kinematics in early evolutionary phases, thus gaining otherwise unaccessible direct information on physical processes in action. The extraction of candidate strongly lensed galaxies (SLGs) from Planck catalogues is hindered by the fact that they are generally detected with poor S/N, except for the few brightest ones, their photometric properties are strongly blurred and they are difficult to single out. We devised a method to increase by a factor of 3 to 4 the number of identified Planck-detected SLGs, although with an unavoidably limited efficiency. Our approach uses the fact that SLGs have sub-mm colours colder than nearby dusty galaxies (the large majority of Planck extragalactic sources). The sub-mm colours of the 47 confirmed or very likely Planck-detected SLGs are used to estimate the colour range of these objects. Moreover, most nearby galaxies and radio sources can be picked up by cross-matching with IRAS and PCNT catalogues, respectively. We present samples of 177, 97, 104 lensed candidates at 545, 857, 353 GHz, respectively. The efficiency of our approach, tested on the SPT survey covering 2,500 sq. deg., is estimated to be of 30%-40%. We also discuss stricter selection criteria increasing efficiency to 50% but with a somewhat lower completeness. Our analysis of SPT data has identified a dozen of galaxies that can be reliably considered previously unrecognized Planck-detected SLGs. Extrapolating the number of Planck-detected confirmed or very likely SLGs found within the SPT and H-ATLAS areas, we expect from 150 to 190 such sources over the|b|>20deg sky., Comment: 18 pages, 6 figures, 5 tables, 1 Appendix. Accepted for publication on Astronomy & Astrophysics

The Additional Representative Images for Legacy (ARI-L) project is a European Development project for ALMA Upgrade approved by the Joint ALMA Observatory (JAO) and the European Southern Observatory (ESO), started in June 2019. It aims to increase the legacy value of the ALMA Science Archive (ASA) by bringing the reduction level of ALMA data from Cycles 2-4 close to that of data from more recent Cycles processed for imaging with the ALMA Pipeline. As of mid-2021 more than 150000 images have been returned to the ASA for public use. At its completion in 2022, the project will have provided enhanced products for at least 70% of the observational data from Cycles 2-4 processable with the ALMA Pipeline. In this paper we present the project rationale, its implementation, and the new opportunities offered to ASA users by the ARI-L products. The ARI-L cubes and images complement the much limited number of archival image products generated during the data quality assurance stages (QA2), which cover only a small fraction of the available data for those Cycles. ARI-L imaging products are highly relevant for many science cases and significantly enhance the possibilities for exploiting archival data. Indeed, ARI-L products facilitate archive access and data usage for science purposes even for non-expert data miners, provide a homogeneous view of all data for better dataset comparisons and download selections, make the archive more accessible to visualization and analysis tools, and enable the generation of preview images and plots similar to those possible for subsequent Cycles., Comment: 15 pages. Accepted for publication in PASP

The magnetic response of a K2Cr3As3 sample has been studied by means of dc magnetization measurements as a function of magnetic field (H) at different temperatures ranging from 5 K up to 300 K. Looking at the magnetic hysteresis loops m(H), a diamagnetic behavior of the sample has been inferred at temperatures higher than 60 K, whereas at lower temperatures the sample shows a hysteresis loop compatible with the presence of ferrimagnetism. Moreover, several spike-like magnetization jumps, both positive and negative, have been observed at certain fields in the range -1000 Oe < H < 1000 Oe, regardless of the temperature considered. The field position of the magnetization jumps has been studied at different temperatures, and their distribution can be described by a Lorentzian curve., Comment: 6 pages, 3 figures