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In the centre of pre-stellar cores, deuterium fractionation is enhanced due to the low temperatures and high densities. Therefore, the chemistry of deuterated molecules can be used to study the earliest stages of star formation. We analyse the deuterium fractionation of simple molecules, comparing the level of deuteration in the envelopes of the pre-stellar core L1544 in Taurus and the protostellar core HH211 in Perseus. We used single-dish observations of CCH, HCN, HNC, HCO$^+$, and their $^{13}$C-, $^{18}$O- and D-bearing isotopologues, detected with the Onsala 20m telescope. We derived the column densities and the deuterium fractions of the molecules. Additionally, we used radiative transfer simulations and results from chemical modelling to reproduce the observed molecular lines. We used new collisional rate coefficients for HNC, HN$^{13}$C, DNC, and DCN that consider the hyperfine structure of these molecules. We find high levels of deuteration for CCH (10%) in both sources, consistent with other carbon chains, and moderate levels for HCN (5-7%) and HNC (8%). The deuterium fraction of HCO$^+$ is enhanced towards HH211, most likely caused by isotope-selective photodissociation of C$^{18}$O. Similar levels of deuteration show that the process is likely equally efficient towards both cores, suggesting that the protostellar envelope still retains the chemical composition of the original pre-stellar core. The fact that the two cores are embedded in different molecular clouds also suggests that environmental conditions do not have a significant effect on the deuteration within dense cores. Radiative transfer modelling shows that it is necessary to include the outer layers of the cores to consider the effects of extended structures. Besides HCO$^+$ observations, HCN observations towards L1544 also require the presence of an outer diffuse layer where the molecules are relatively abundant., Comment: 27 pages, 17 figures, accepted for publication in A&A

Context: In the centre of pre-stellar cores, the deuterium fractionation is enhanced due to the cold temperatures and high densities. Therefore, the chemistry of deuterated molecules can be used to probe the evolution and the kinematics in the earliest stages of star formation. Aims: We analyse emission maps of cyclopropenylidene, c-C$_3$H$_2$, to study the distribution of the deuteration throughout the prototypical pre-stellar core L1544. Methods: We use single-dish observations of c-C$_3$H$_2$, c-H$^{13}$CC$_2$H, c-C$_3$HD, and c-C$_3$D$_2$ towards the pre-stellar core L1544, performed at the IRAM 30m telescope. We derive the column density and deuterium fraction maps, and compare these observations with non-LTE radiative transfer simulations. Results: The highest deuterium fractions are found close to the dust peak at the centre of L1544, where the increased abundance of H$_2$D$^+$ ions drives the deuteration process. The peak values are N(c-C$_3$HD)/N(c-C$_3$H$_2)=0.17\pm0.01$, N(c-C$_3$D$_2$)/N(c-C$_3$H$_2)=0.025\pm0.003$ and N(c-C$_3$D$_2$)/N(c-C$_3$HD$)=0.16\pm0.03$, which is consistent with previous single point observations. The distributions of c-C$_3$HD and c-C$_3$D$_2$ indicate that the deuterated forms of c-C$_3$H$_2$ in fact trace the dust peak and not the c-C$_3$H$_2$ peak. Conclusions: The N(c-C$_3$D$_2$)/N(c-C$_3$HD) map confirms that the process of deuteration is more efficient towards the centre of the core and demonstrates that carbon-chain molecules are still present at high densities. This is likely caused by an increased abundance of He$^+$ ions destroying CO, which increases the amount of carbon atoms in the gas phase., 13 pages, 9 figures

High-mass star formation theories make distinct predictions on the properties of the prestellar seeds of high-mass stars. Observations of the early stages of high-mass star formation can provide crucial constraints, but they are challenging and scarce. We investigate the properties of the prestellar core population embedded in the high-mass clump AGAL014.492-00.139, and we study the kinematics at the clump and the clump-to-core scales. We have analysed an extensive dataset acquired with the ALMA interferometer. Applying a dendrogram analysis to the Band o-$\rm H_2D^+$ data, we identified 22 cores. We have fitted their average spectra in local-thermodinamic-equilibrium conditions, and we analysed their continuum emission at $0.8 \, \rm mm$. The cores have transonic to mildly supersonic turbulence levels and appear mostly low-mass, with $M_\mathrm{core}< 30 \, \rm M_\odot$. Furthermore, we have analysed Band 3 observations of the $\rm N_2H^+$ (1-0) transition, which traces the large scale gas kinematics. Using a friend-of-friend algorithm, we identify four main velocity coherent structures, all of which are associated with prestellar and protostellar cores. One of them presents a filament-like structure, and our observations could be consistent with mass accretion towards one of the protostars. In this case, we estimate a mass accretion rate of $ \dot{M}_\mathrm{acc}\approx 2 \times 10^{-4} \rm \, M_\odot \, yr^{-1}$. Our results support a clump-fed accretion scenario in the targeted source. The cores in prestellar stage are essentially low-mass, and they appear subvirial and gravitationally bound, unless further support is available for instance due to magnetic fields., Accepted for publication in ApJ

Ground-based and airborne instrumentation for astronomy IX (2022), Montreal, JUL 17-22, 2022.--Proceedings of SPIE - The International Society for Optical Engineering vol. 12184 Article number 1218424.-- Complete list of authors: Marconi, A.; Abreu, M.; Adibekyan, V.; Alberti, V.; Albrecht, S.; Alcaniz, J.; Aliverti, M.; Allende Prieto, C.; Gomez, J. D. Alvarado; Amado, P. J.; Amate, M.; Andersen, M. I.; Artigau, E.; Baker, C.; Baldini, V.; Balestra, A.; Barnes, S. A.; Baron, F.; Barros, S. C. C.; Bauer, S. M.; Beaulieu, M.; Bellido-Tirado, O.; Benneke, B.; Bensby, T.; Bergin, E. A.; Biazzo, K.; Bik, A.; Birkby, J. L.; Blind, N.; Boisse, I.; Bolmont, E.; Bonaglia, M.; Bonfils, X.; Borsa, F.; Brandeker, A.; Brandner, W.; Broeg, C. H.; Brogi, M.; Brousseau, D.; Brucalassi, A.; Brynnel, J.; Buchhave, L. A.; Buscher, D. F.; Cabral, A.; Calderone, G.; Calvo-Ortega, R.; Cantalloube, F.; Canto Martins, B. L.; Carbonaro, L.; Chauvin, G.; Chazelas, B.; Cheffot, A. -L.; Cheng, Y. S.; Chiavassa, A.; Christensen, L.; Cirami, R.; Cook, N. J.; Cooke, R. J.; Coretti, I.; Covino, S.; Cowan, N.; Cresci, G.; Cristiani, S.; Cunha Parro, V.; Cupani, G.; D'Odorico, V.; de Castro Leao, I.; De Cia, A.; De Medeiros, J. R.; Debras, F.; Debus, M.; Demangeon, O.; Dessauges-Zavadsky, M.; Di Marcantonio, P.; Dionies, F.; Doyon, R.; Dunn, J.; Ehrenreich, D.; Faria, J. P.; Feruglio, C.; Fisher, M.; Fontana, A.; Fumagalli, M.; Fusco, T.; Fynbo, J.; Gabella, O.; Gaessler, W.; Gallo, E.; Gao, X.; Genolet, L.; Genoni, M.; Giacobbe, P.; Giro, E.; Goncalves, R. S.; Gonzalez, O. A.; Gonzalez Hernandez, J. I.; Gracia Temich, F.; Haehnelt, M. G.; Haniff, C.; Hatzes, A.; Helled, R.; Hoeijmakers, H. J.; Huke, P.; Jaervinen, A. S.; Jaervinen, S. P.; Kaminski, A.; Korn, A. J.; Kouach, D.; Kowzan, G.; Kreidberg, L.; Landoni, M.; Lanotte, A.; Lavail, A.; Li, J.; Liske, J.; Lovis, C.; Lucatello, S.; Lunney, D.; MacIntosh, M. J.; Madhusudhan, N.; Magrini, L.; Maiolino, R.; Malo, L.; Man, A. W. S.; Marquart, T.; Marques, E. L.; Martins, C. J. A. P.; Martins, A. M.; Maslowski, P.; Mason, E.; Mason, C. A.; McCracken, R. A.; Mergo, P.; Micela, G.; Mitchell, T.; Molliere, P.; Monteiro, M. A.; Montgomery, D.; Mordasini, C.; Morin, J.; Mucciarelli, A.; Murphy, M. T.; N'Diaye, M.; Neichel, B.; Niedzielski, A. T.; Niemczura, E.; Nortmann, L.; Noterdaeme, P.; Nunes, N. J.; Oggioni, L.; Oliva, E.; Onel, H.; Origlia, L.; Ostlin, G.; Palle, E.; Papaderos, P.; Pariani, G.; Penate Castro, J.; Pepe, F.; Levasseur, L. Perreault; Petit, P.; Pino, L.; Piqueras, J.; Pollo, A.; Poppenhaeger, K.; Quirrenbach, A.; Rauscher, E.; Rebolo, R.; Redaelli, E. M. A.; Reffert, S.; Reid, D. T.; Reiners, A.; Richter, P.; Riva, M.; Rivoire, S.; Rodriguez-Lopez, C.; Roederer, I. U.; Romano, D.; Rousseau, S.; Rowe, J.; Salvadori, S.; Sanna, N.; Santos, N. C.; Diaz, P. Santos; Sanz-Forcada, J.; Sarajlic, M.; Sauvage, J. -F.; Schaefer, S.; Schiavon, R. P.; Schmidt, T. M.; Selmi, C.; Sivanandam, S.; Sordet, M.; Sordo, R.; Sortino, F.; Sosnowska, D.; Sousa, S. G.; Stempels, E.; Strassmeier, K. G.; Suarez Mascareno, A.; Sulich, A.; Sun, X.; Tanvir, N. R.; Tenegi-Sangines, F.; Thibault, S.; Thompson, S. J.; Tozzi, A.; Turbet, M.; Vallee, P.; Varas, R.; Venn, K. A.; Veran, J. -P.; Verma, A.; Viel, M.; Wade, G.; Waring, C.; Weber, M.; Weder, J.; Wehbe, B.; Weingrill, J.; Woche, M.; Xompero, M.; Zackrisson, E.; Zanutta, A.; Zapatero Osorio, M. R.; Zechmeister, M.; Zimara, J., The first generation of ELT instruments includes an optical-infrared high resolution spectrograph, indicated as ELT-HIRES and recently christened ANDES (ArmazoNes high Dispersion Echelle Spectrograph). ANDES consists of three fibre-fed spectrographs (UBV, RIZ, YJH) providing a spectral resolution of similar to 100,000 with a minimum simultaneous wavelength coverage of 0.4-1.8 mu m with the goal of extending it to 0.35-2.4 mu m with the addition of a K band spectrograph. It operates both in seeing- and diffraction-limited conditions and the fibre-feeding allows several, interchangeable observing modes including a single conjugated adaptive optics module and a small diffraction-limited integral field unit in the NIR. Its modularity will ensure that ANDES can be placed entirely on the ELT Nasmyth platform, if enough mass and volume is available, or partly in the Coude room. ANDES has a wide range of groundbreaking science cases spanning nearly all areas of research in astrophysics and even fundamental physics. Among the top science cases there are the detection of biosignatures from exoplanet atmospheres, finding the fingerprints of the first generation of stars, tests on the stability of Nature's fundamental couplings, and the direct detection of the cosmic acceleration. The ANDES project is carried forward by a large international consortium, composed of 35 Institutes from 13 countries, forming a team of more than 200 scientists and engineers which represent the majority of the scientific and technical expertise in the field among ESO member states., The Italian effort for ANDES is supported by the Italian National Institute for Astrophysics (INAF). The Portuguese participation is supported by FCT -Fundacao para a Ciencia e a Tecnologia through national funds and by FEDER through COMPETE2020 -Programa Operacional Competitividade e Internacionalizacao by these grants: UID/FIS/04434/2019, UIDB/04434/2020 & UIDP/04434/2020; POCI-01-0145-FEDER-032113 & PTDC/FIS-AST/32113/2017. Swedish participation in the ANDES project is made possible through the national Swedish ELT Instrumentation Consortium (SELTIC), suppored by the Swedish Research Council (VR). CJM acknowledges FCT and POCH/FSE (EC) support through Investigador FCT Contract 2021.01214.CEECIND/CP1658/CT0001. JLB acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under grant agreement No 805445. MTM acknowledges the support of the Australian Research Council through Future Fellowship grant FT180100194 SS acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program under grant agreement No 804240. TMS acknowledgment the support from the SNF synergia grant CRSII5-193689 (BLUVES), With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709

We aim to quantify the effect of chemistry on the infall velocity in the prestellar core L1544. Previous observational studies have found evidence for double-peaked line profiles for the rotational transitions of several molecules, which cannot be accounted for with the models presently available for the physical structure of the source, without ad hoc up-scaling of the infall velocity. We ran one-dimensional hydrodynamical simulations of the collapse of a core with L1544-like properties (in terms of mass and outer radius), using a state-of-the-art chemical model with a very large chemical network combined with an extensive description of molecular line cooling, determined via radiative transfer simulations, with the aim of determining whether these expansions of the simulation setup (as compared to previous models) can lead to a higher infall velocity. After running a series of simulations where the simulation was sequentially simplified, we found that the infall velocity is almost independent of the size of the chemical network or the approach to line cooling. We conclude that chemical evolution does not have a large impact on the infall velocity, and that the higher infall velocities that are implied by observations may be the result of the core being more dynamically evolved than what is now thought, or alternatively the average density in the simulated core is too low. However, chemistry does have a large influence on the lifetime of the core, which varies by about a factor of two across the simulations and grows longer when the chemical network is simplified. Therefore, although the model is subject to several sources of uncertainties, the present results clearly indicate that the use of a small chemical network leads to an incorrect estimate of the core lifetime, which is naturally a critical parameter for the development of chemical complexity in the precollapse phase., Comment: 12 pages incl. Appendix; 8 figures; accepted to A&A; replacement to reflect the change of the title of the paper post-acceptance

Context. Spectral line profiles of several molecules observed towards the pre-stellar core L1544 appear double-peaked. For abundant molecular species this line morphology has been linked to self-absorption. However, the physical process behind the double-peaked morphology for less abundant species is still under debate. Aims. In order to understand the cause behind the double-peaked spectra of optically thin transitions and their link to the physical structure of pre-stellar cores, we present high-sensitivity and high spectral resolution HC17O+ J =1−0 observations towards the dust peak in L1544. Methods. We observed the HC17O+(1−0) spectrum with the Institut de Radioastronomie Millimétrique (IRAM) 30 m telescope. By using state-of-the-art collisional rate coefficients, a physical model for the core and the fractional abundance profile of HC17O+, the hyperfine structure of this molecular ion is modelled for the first time with the radiative transfer code loc applied to the predicted chemical structure of a contracting pre-stellar core. We applied the same analysis to the chemically related C17O molecule. Results. The observed HC17O+(1−0) and C17O(1−0) lines were successfully reproduced with a non-local thermal equilibrium (LTE) radiative transfer model applied to chemical model predictions for a contracting pre-stellar core. An upscaled velocity profile (by 30%) is needed to reproduce the HC17O+(1−0) observations. Conclusions. The double peaks observed in the HC17O+(1−0) hyperfine components are due to the contraction motions at densities close to the critical density of the transition (~105 cm−3) and to the decreasing HCO+ fractional abundance towards the centre.

Based on guaranteed time observations collected at the European Southern Observatory under ESO programme 1102.C-0744 by the ESPRESSO Consortium. Aims. We report on ESPRESSO high-resolution transmission spectroscopic observations of two primary transits of the highly irradiated, ultra-hot Jupiter-sized planet, WASP-76b. We investigated the presence of several key atomic and molecular features of interest that may reveal the atmospheric properties of the planet. Methods. We extracted two transmission spectra of WASP-76b with R ≈ 140 000 using a procedure that allowed us to process the full ESPRESSO wavelength range (3800–7880 Å) simultaneously. We observed that at a high signal-to-noise ratio, the continuum of ESPRESSO spectra shows ‘wiggles’, which are likely caused by an interference pattern outside the spectrograph. To search for the planetary features, we visually analysed the extracted transmission spectra and cross-correlated the observations against theoretical spectra of different atomic and molecular species. Results. The following atomic features are detected: Li I, Na I, Mg I, Ca II, Mn I, K I, and Fe I. All are detected with a confidence level between 9.2 σ (Na I) and 2.8 σ (Mg I). We did not detect the following species: Ti I, Cr I, Ni I, TiO, VO, and ZrO. We impose the following 1 σ upper limits on their detectability: 60, 77, 122, 6, 8, and 8 ppm, respectively. Conclusions. We report the detection of Li I on WASP-76b for the first time. In addition, we confirm the presence of Na I and Fe I as previously reported in the literature. We show that the procedure employed in this work can detect features down to the level of ~0.1% in the transmission spectrum and ~10 ppm by means of a cross-correlation method. We discuss the presence of neutral and singly ionised features in the atmosphere of WASP-76b. This work was supported by FCT - FundacAo para a Ciencia e a Tecnologia through national funds and by FEDER through COMPETE2020 - Programa Operacional Competitividade e InternacionalizacAo by these grants: UID/FIS/04434/2019; UIDB/04434/2020; UIDP/04434/2020; PTDC/FIS-AST/ 32113/2017 & POCI-01-0145-FEDER-032113; PTDC/FIS-AST/28953/2017 & POCI-01-0145-FEDER-028953; PTDC/FIS-AST/28987/2017 & POCI-01- 0145-FEDER-028987. V.A., S.G.S., S.C.C.B. acknowledge support from FCT through Investigador FCT contracts ns degrees IF/00650/2015/CP1273/CT0001; IF/00028/2014/CP1215/CT0002; IF/01312/2014/CP1215/CT0004. S.G.S acknowledges the support from FCT through Investigador FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). J.P.F., O.D., and J.H.C.M. acknowledge support from FCT through national funds in the form of a work contract with the references DL 57/2016/CP1364/CT0005; DL 57/2016/CP1364/CT0004; DL 57/2016/CP1364/CT0007. H.M.T. and M.R.Z.O. acknowledge financial support from the Spanish Ministerio de Ciencia, Innovacion y Universidades (MICIU) through project AYA2016-79425-C3-2. A.S.M., R.R., J.I.G.H., C.A.P. acknowledge financial support from the Spanish MICIU project AYA2017-86389-P. J.I.G.H. acknowledges financial support from the Spanish MICIU under the 2013 Ramon y Cajal program RYC-2013-14875. This work has been carried out within the framework of the National Centre of Competence in Research PlanetS supported by the Swiss National Science Foundation. The authors acknowledge the financial support of the SNSF. The INAF authors acknowledge financial support of the Italian Ministry of Education, University, and Research with PRIN 201278X4FL and the Progetti Premiali funding scheme. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (projectFOUR ACES; grant agreement No 724427). N.J.N. acknowledges support from FCT through Investigador FCT contract and exploratory project IF/00852/2015, and project PTDC/FIS-OUT/29048/2017. J.V.S. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (project Four Aces; grant agreement No. 724427). Peerreview

Deuterium fractionation processes in the interstellar medium (ISM) have been shown to be highly efficient in the family of nitrogen hydrides. To date, observations were limited to ammonia (NH$_2$D, NHD$_2$, ND$_3$) and imidogen radical (ND) isotopologues. We want to explore the high frequency windows offered by the \emph{Herschel Space Observatory} to search for deuterated forms of amidogen radical NH$_2$ and to compare the observations against the predictions of our comprehensive gas-grain chemical model. Making use of the new molecular spectroscopy data recently obtained at high frequencies for NHD and ND$_2$, both isotopologues have been searched for in the spectral survey towards the class 0 IRAS 16293-2422, a source in which NH$_3$, NH and their deuterated variants have been previously detected. We used the observations carried out with HIFI (Heterodyne Instrument for the Far Infrared) in the framework of the key program "Chemical Herschel surveys of star forming regions" (CHESS). We report the first detection of interstellar NHD and ND$_2$. Both species are observed in absorption against the continuum of the protostar. From the analysis of their hyperfine structure, accurate excitation temperature and column density values have been determined. The latter were combined with the column density of the parent species NH$_2$ to derive the deuterium fractionation in amidogen. The amidogen D/H ratio measured in the low-mass protostar IRAS 16293-2422 is comparable to the one derived for the related species imidogen and much higher than that observed for ammonia. Additional observations of these species will give more insights into the mechanism of ammonia formation and deuteration in the ISM. We finally indicate the current possibilities to further explore these species at submillimeter wavelengths., 11 pages, 5 figures, 7 tables. Accepted for publication in A&A

The bright star $��$ Men was chosen as the first target for a radial velocity follow-up to test the performance of ESPRESSO, the new high-resolution spectrograph at the ESO's Very-Large Telescope (VLT). The star hosts a multi-planet system (a transiting 4 M$_\oplus$ planet at $\sim$0.07 au, and a sub-stellar companion on a $\sim$2100-day eccentric orbit) which is particularly appealing for a precise multi-technique characterization. With the new ESPRESSO observations, that cover a time span of 200 days, we aim to improve the precision and accuracy of the planet parameters and search for additional low-mass companions. We also take advantage of new photometric transits of $��$ Men c observed by TESS over a time span that overlaps with that of the ESPRESSO follow-up campaign. We analyse the enlarged spectroscopic and photometric datasets and compare the results to those in the literature. We further characterize the system by means of absolute astrometry with Hipparcos and Gaia. We used the spectra of ESPRESSO for an independent determination of the stellar fundamental parameters. We present a precise characterization of the planetary system around $��$ Men. The ESPRESSO radial velocities alone (with typical uncertainty of 10 cm/s) allow for a precise retrieval of the Doppler signal induced by $��$ Men c. The residuals show an RMS of 1.2 m/s, and we can exclude companions with a minimum mass less than $\sim$2 M$_\oplus$ within the orbit of $��$ Men c). We improve the ephemeris of $��$ Men c using 18 additional TESS transits, and in combination with the astrometric measurements, we determine the inclination of the orbital plane of $��$ Men b with high precision ($i_{b}=45.8^{+1.4}_{-1.1}$ deg). This leads to the precise measurement of its absolute mass $m_{b}=14.1^{+0.5}_{-0.4}$ M$_{Jup}$, and shows that the planetary orbital planes are highly misaligned., Accepted for publication on A&A

Context. Star formation takes place in cold dense cores in molecular clouds. Earlier observations have found that dense cores exhibit subsonic non-thermal velocity dispersions. In contrast, CO observations show that the ambient large-scale cloud is warmer and has supersonic velocity dispersions. Aims. We aim to study the ammonia (NH3) molecular line profiles with exquisite sensitivity towards the coherent cores in L1688 in order to study their kinematical properties in unprecedented detail. Methods. We used NH3 (1,1) and (2,2) data from the first data release (DR1) in the Green Bank Ammonia Survey (GAS). We first smoothed the data to a larger beam of 10 to obtain substantially more extended maps of velocity dispersion and kinetic temperature, compared to the DR1 maps. We then identified the coherent cores in the cloud and analysed the averaged line profiles towards the cores. Results. For the first time, we detected a faint (mean NH3(1,1) peak brightness 0.25K in TMB), supersonic component towards all the coherent cores in L1688. We fitted two components, one broad and one narrow, and derived the kinetic temperature and velocity dispersion of each component. The broad components towards all cores have supersonic linewidths (MS 1). This component biases the estimate of the narrow dense core component's velocity dispersion by 28% and the kinetic temperature by 10%, on average, as compared to the results from single-component fits. Conclusions. Neglecting this ubiquitous presence of a broad component towards all coherent cores causes the typical singlecomponent fit to overestimate the temperature and velocity dispersion. This aects the derived detailed physical structure and stability of the cores estimated from NH3 observations. © S. Choudhury et al. 2020. Acknowledgements. AP is supported by the Russian Ministry of Science and Higher Education via the State Assignment Project FEUZ-2020-0038. AP is a member of the Max Planck Partner Group at the Ural Federal University. SSRO acknowledges support from NSF CAREER grant. AC-T acknowledges support from MINECO project AYA2016-79006-P.

The Multi-Core Integral-Field Unit (MCIFU) is a new diffraction-limited near-infrared integral-field unit for exoplanet atmosphere characterization with extreme adaptive optics (xAO) instruments. It has been developed as an experimental pathfinder for spectroscopic upgrades for SPHERE+/VLT and other xAO systems. The wavelength range covers 1.0 um to 1.6um at a resolving power around 5000 for 73 points on-sky. The MCIFU uses novel astrophotonic components to make this very compact and robust spectrograph. We performed the first successful on-sky test with CANARY at the 4.2 meter William Herschel Telescope in July 2019, where observed standard stars and several stellar binaries. An improved version of the MCIFU will be used with MagAO-X, the new extreme adaptive optics system at the 6.5 meter Magellan Clay telescope in Chile. We will show and discuss the first-light performance and operations of the MCIFU at CANARY and discuss the integration of the MCIFU with MagAO-X.

Si sono effettuate simulazioni numeriche finalizzate alla determinazione della distribuzione del potenziale e della corrente in elementi in calcestruzzo armato parzialmente immersi in acqua di mare con lo scopo di prevedere il potere penetrante della prevenzione catodica applicata con anodi sacrifiziali. Si sono considerati modelli bidimensionali di colonne in calcestruzzo armato contenenti armature di acciaio a diverse altezze protette con anodi sacrifiziali posti nell’acqua in cui erano parzialmente immerse. Le condizioni al contorno per la descrizione del comportamento elettrochimico delle armature e i valori della resistività elettrica del calcestruzzo alle diverse altezze dal livello dell’acqua sono stati ricavati da prove sperimentali di laboratorio effettuate su provini in calcestruzzo armato. Nelle simulazioni si sono considerate diverse condizioni di comportamento elettrochimico delle armature, dimensioni dell’elemento e posizione degli anodi sacrifiziali. La nota riporta i risultati ottenuti dai modelli e confronta il potere penetrante che può essere raggiunto usando anodi sacrifiziali immersi in acqua di mare per proteggere le armature nella parte emersa di elementi in calcestruzzo

The bright star π Men was chosen as the first target for a radial velocity follow-up to test the performance of ESPRESSO, the new high-resolution spectrograph at the ESO's Very-Large Telescope (VLT). The star hosts a multi-planet system (a transiting 4 M⊕ planet at ∼0.07 au, and a sub-stellar companion on a ∼2100-day eccentric orbit) which is particularly appealing for a precise multi-technique characterization. With the new ESPRESSO observations, that cover a time span of 200 days, we aim to improve the precision and accuracy of the planet parameters and search for additional low-mass companions. We also take advantage of new photometric transits of π Men c observed by TESS over a time span that overlaps with that of the ESPRESSO follow-up campaign. We analyse the enlarged spectroscopic and photometric datasets and compare the results to those in the literature. We further characterize the system by means of absolute astrometry with Hipparcos and Gaia. We used the spectra of ESPRESSO for an independent determination of the stellar fundamental parameters. We present a precise characterization of the planetary system around π Men. The ESPRESSO radial velocities alone (with typical uncertainty of 10 cm/s) allow for a precise retrieval of the Doppler signal induced by π Men c. The residuals show an RMS of 1.2 m/s, and we can exclude companions with a minimum mass less than ∼2 M⊕ within the orbit of π Men c). We improve the ephemeris of π Men c using 18 additional TESS transits, and in combination with the astrometric measurements, we determine the inclination of the orbital plane of π Men b with high precision (ib=45.8+1.4−1.1 deg). This leads to the precise measurement of its absolute mass mb=14.1+0.5−0.4 MJup, and shows that the planetary orbital planes are highly misaligned.

We characterized the transiting planetary system orbiting the G2V star K2-38 using the new-generation echelle spectrograph ESPRESSO. We carried out a photometric analysis of the available K2 photometric light curve of this star to measure the radius of its two known planets. Using 43 ESPRESSO high-precision radial velocity measurements taken over the course of 8 months along with the 14 previously published HIRES RV measurements, we modeled the orbits of the two planets through a MCMC analysis, significantly improving their mass measurements. Using ESPRESSO spectra, we derived the stellar parameters, Teff=5731±66, logg=4.38±0.11~dex, and [Fe/H]=0.26±0.05~dex, and thus the mass and radius of K2-38, M⋆=1.03 +0.04−0.02~M⊕ and R⋆=1.06 +0.09−0.06~R⊕. We determine new values for the planetary properties of both planets. We characterize K2-38b as a super-Earth with RP=1.54±0.14~R⊕ and Mp=7.3+1.1−1.0~M⊕, and K2-38c as a sub-Neptune with RP=2.29±0.26~R⊕ and Mp=8.3+1.3−1.3~M⊕. We derived a mean density of ρp=11.0+4.1−2.8~g cm−3 for K2-38b and ρp=3.8+1.8−1.1~g~cm−3 for K2-38c, confirming K2-38b as one of the densest planets known to date. The best description for the composition of K2-38b comes from an iron-rich Mercury-like model, while K2-38c is better described by a rocky model with a H2 envelope. The maximum collision stripping boundary shows how giant impacts could be the cause for the high density of K2-38b. The irradiation received by each planet places them on opposite sides of the radius valley. We find evidence of a long-period signal in the radial velocity time-series whose origin could be linked to a 0.25-3~MJ planet or stellar activity.

The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of “green” concrete but that the sustainability of the building materials can only be achieved by implementing simultaneous multiple strategies aimed at reducing environmental impact and improving both durability and performances.

Context. The nitrogen isotopic ratio is considered an important diagnostic tool of the star formation process, and $N_2H^+$ is particularly important because it is directly linked to molecular nitrogen $N_2$. However, theoretical models still lack to provide an exhaustive explanation for the observed $^{14}N/^{15}N$ values. Aims. Recent theoretical works suggest that the $^{14}N/^{15}N$ behaviour is dominated by two competing reactions that destroy $ N_2H^+$: dissociative recombination and reaction with CO. When CO is depleted from the gas phase, if $N_2H^+$ recombination rate is lower with respect to the $N^{15}NH^+$ one, the rarer isotopologue is destroyed faster. This implies that the $N_2H^+$ isotopic ratio in protostars should be lower than the one in prestellar cores, and consistent with the elemental value of ~440. We aim to test this hypothesis, producing the first sample of $N_2H^+ / N^{15}NH^+$ measurements in low mass protostars. Methods. We observe the $N_2H^+$ and $N^{15}NH^+$ lowest rotational transition towards six young stellar objects in Perseus and Taurus molecular clouds. We model the spectra with a custom python code using a constant $T_{ex}$ approach to fit the observations. We discuss in appendix the validity of this hypothesis. The derived column densities are used to compute the nitrogen isotopic ratio. Results. Our analysis yields an average of $\rm ^{14}N/^{15}N|_{pro} = 420 \pm 15$ in the protostellar sample. This is consistent with the protosolar value of 440, and significantly lower than the average value previously obtained in a sample of prestellar objects. Conclusions. Our results are in agreement with the hypothesis that, when CO is depleted from the gas-phase, dissociative recombinations with free electrons destroy $N^{15}NH^+$ faster than $N_2H^+$, leading to high isotopic ratios in prestellar cores, where CO is frozen on dust grains., Accepted on A&A on 09 Oct 2020

Sodium channel myotonia is a form of muscle channelopathy due to mutations that affect the Nav1.4 channel. We describe seven families with a series of symptoms ranging from asymptomatic to clearly myotonic signs that have in common two novel mutations, p.Ile215Thr and p.Gly241Val, in the first domain of the Nav1.4 channel. The families described have been clinically and genetically evaluated. p.Ile215Thr and p.Gly241Val lie, respectively, on extracellular and intracellular loops of the first domain of the Nav1.4 channel. We assessed that the p.Ile215Thr mutation can be related to a founder effect in people from Southern Italy. Electrophysiological evaluation of the channel function showed that the voltage dependence of the activation for both the mutant channels was significantly shifted toward hyperpolarized potentials (Ile215Thr: −28.6 ± 1.5 mV and Gly241Val: −30.2 ± 1.3 mV vs. WT: −18.5 ± 1.3 mV). The slow inactivation was also significantly affected, whereas fast inactivation showed a different behavior in the two mutants. We characterized two novel mutations of the SCN4A gene expanding the knowledge about genetics of mild forms of myotonia, and we present, to our knowledge, the first homozygous patient with sodium channel myotonia.

Context. Phosphorus-bearing species are essential to the formation of life on Earth, however they have barely been detected in the interstellar medium. In particular, towards star-forming regions only PN and PO have been identified so far. Since only a small number of detections of P-bearing molecules are available, their chemical formation pathways are not easy to constrain and are thus highly debatable. An important factor still missing in the chemical models is the initial elemental abundance of phosphorus, that is, the depletion level of P at the start of chemical models of dense clouds. Aims. In order to overcome this problem, we study P-bearing species in diffuse and translucent clouds. In these objects phosphorus is expected to be mainly in the gas phase and therefore the elemental initial abundance needed in our chemical simulations corresponds to the cosmic one and is well constrained. Methods. For the study of P-bearing chemistry we used an advanced chemical model. We updated and significantly extended the P-chemistry network based on chemical databases and previous literature. We performed single-pointing observations with the IRAM 30 m telescope in the 3 mm range towards the line of sight to the strong continuum source B0355+508 aiming for the (2-1) transitions of PN, PO, HCP, and CP. This line of sight incorporates five diffuse and/or translucent clouds. Results. The (2-1) transitions of the PN, PO, HCP, and CP were not detected. We report high signal-to-noise-ratio detections of the (1-0) lines of 13CO, HNC, and CN along with a first detection of C34S towards this line of sight. We have attempted to reproduce the observations of HNC, CN, CS, and CO in every cloud with our model by applying typical physical conditions for diffuse or translucent clouds. We find that towards the densest clouds with vLSR = -10, - 17 km s-1 the best-fit model is given by the parameters (n(H), AV, Tgas) = (300 cm-3, 3 mag, 40 K). Conclusions. According to our best-fit model, the most abundant P-bearing species are HCP and CP (~10-10). The molecules PN, PO, and PH3 also show relatively high predicted abundances of ~10-11. We show that the abundances of these species are sensitive to visual extinction, cosmic-ray ionization rate, and the diffusion-to-desorption energy ratio on dust grains. The production of P-bearing species is favored towards translucent rather than diffuse clouds, where the environment provides a stronger shielding from the interstellar radiation. Based on our improved model, we show that the (1-0) transitions of HCP, CP, PN, and PO are expected to be detectable with estimated intensities of up to ~200 mK. © J. Chantzos et al. 2020. Horizon 2020 Framework Programme, H2020: 66493 lzp-2018/1-0170 We thank the anonymous referee for his/her comments that significantly improved the present manuscript. The authors also wish to thank the IRAM Granada staff for their help during the observations. V.M.R. has received funding from the European Unions Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant agreement No 66493. Work by A.V. is supported by the Latvian Science Council via the project lzp-2018/1-0170. J.C. acknowledges Dr. J. C. Laas for his support with the Python programming.

L1521E is a dense starless core in Taurus that was found to have relatively low molecular depletion by earlier studies, thus suggesting a recent formation. We aim to characterize the chemical structure of L1521E and compare it to the more evolved L1544 pre-stellar core. We have obtained $\sim$2.5$\times$2.5 arcminute maps toward L1521E using the IRAM-30m telescope in transitions of various species. We derived abundances for the species and compared them to those obtained toward L1544. We estimated CO depletion factors. Similarly to L1544, $c$-C$_3$H$_2$ and CH$_3$OH peak at different positions. Most species peak toward the $c$-C$_3$H$_2$ peak. The CO depletion factor derived toward the $Herschel$ dust peak is 4.3$\pm$1.6, which is about a factor of three lower than that toward L1544. The abundances of sulfur-bearing molecules are higher toward L1521E than toward L1544 by factors of $\sim$2-20. The abundance of methanol is similar toward the two cores. The higher abundances of sulfur-bearing species toward L1521E than toward L1544 suggest that significant sulfur depletion takes place during the dynamical evolution of dense cores, from the starless to pre-stellar stage. The CO depletion factor measured toward L1521E suggests that CO is more depleted than previously found. Similar CH$_3$OH abundances between L1521E and L1544 hint that methanol is forming at specific physical conditions in Taurus, characterized by densities of a few $\times$10$^4$ cm$^{-3}$ and $N$(H$_2$)$\gtrsim$10$^{22}$ cm$^{-2}$, when CO starts to catastrophically freeze-out, while water can still be significantly photodissociated, so that the surfaces of dust grains become rich in solid CO and CH$_3$OH, as already found toward L1544. Methanol can thus provide selective crucial information about the transition region between dense cores and the surrounding parent cloud., Comment: Accepted for publication in A&A, abstract abridged

We carried out a parameter-space exploration of the ammonia abundance in the pre-stellar core L1544, where it has been observed to increase toward the center of the core with no signs of freeze-out onto grain surfaces. We considered static and dynamical physical models coupled with elaborate chemical and radiative transfer calculations, and explored the effects of varying model parameters on the (ortho+para) ammonia abundance profile. None of our models are able to reproduce the inward-increasing tendency in the observed profile; ammonia depletion always occurs in the center of the core. In particular, our study shows that including the chemical desorption process, where exothermic association reactions on the grain surface can result in the immediate desorption of the product molecule, leads to ammonia abundances that are over an order of magnitude above the observed level in the innermost 15000 au of the core - at least when one employs a constant efficiency for the chemical desorption process irrespective of the ice composition. Our results seemingly constrain the chemical desorption efficiency of ammonia on water ice to below 1%. It is increasingly evident that time-dependent effects must be considered so that the results of chemical models can be reconciled with observations., Accepted to MNRAS