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CO2 and NO2 formation on amorphous solid water Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-23 Meenu Upadhyay, Markus Meuwly
Context. The dynamics of molecule formation, relaxation, diffusion, and desorption on amorphous solid water (ASW) is studied in a quantitative fashion.Aims. The formation probability, stabilization, energy relaxation, and diffusion dynamics of CO2 and NO2 on cold ASW following atom+diatom recombination reactions are characterized quantitatively.Methods. Accurate machine-learned energy functions combined
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The SRG/eROSITA all-sky survey Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-23 V. Ghirardini, E. Bulbul, E. Artis, N. Clerc, C. Garrel, S. Grandis, M. Kluge, A. Liu, Y. E. Bahar, F. Balzer, I. Chiu, J. Comparat, D. Gruen, F. Kleinebreil, S. Krippendorf, A. Merloni, K. Nandra, N. Okabe, F. Pacaud, P. Predehl, M. E. Ramos-Ceja, T. H. Reiprich, J. S. Sanders, T. Schrabback, R. Seppi, S. Zelmer, X. Zhang, W. Bornemann, H. Brunner, V. Burwitz, D. Coutinho, K. Dennerl, M. Freyberg
The evolution of the cluster mass function traces the growth of linear density perturbations, providing valuable insights into the growth of structures, the nature of dark matter, and the cosmological parameters governing the Universe. The primary science goal of eROSITA, on board the Spectrum Roentgen Gamma (SRG) mission, is to constrain cosmology through the evolution of the cluster mass function
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Soft X-ray emission from the classical nova AT 2018bej Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-23 A. Tavleev, L. Ducci, V. F. Suleimanov, C. Maitra, K. Werner, A. Santangelo, V. Doroshenko
Context. Classical novae are known to demonstrate a supersoft X-ray source (SSS) state following outbursts. This state is associated with residual thermonuclear burning on the white dwarf (WD) surface. During its all-sky survey (eRASS1), the eROSITA telescope on board the Spectrum-Roentgen-Gamma observatory discovered a bright new SSS, whose position is consistent with the known classical nova AT 2018bej
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Euclid preparation Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-19 B. Aussel, S. Kruk, M. Walmsley, M. Huertas-Company, M. Castellano, C. J. Conselice, M. Delli Veneri, H. Domínguez Sánchez, P.-A. Duc, J. H. Knapen, U. Kuchner, A. La Marca, B. Margalef-Bentabol, F. R. Marleau, G. Stevens, Y. Toba, C. Tortora, L. Wang, N. Aghanim, B. Altieri, A. Amara, S. Andreon, N. Auricchio, M. Baldi, S. Bardelli, R. Bender, C. Bodendorf, D. Bonino, E. Branchini, M. Brescia, J.
The Euclid mission is expected to image millions of galaxies at high resolution, providing an extensive dataset with which to study galaxy evolution. Because galaxy morphology is both a fundamental parameter and one that is hard to determine for large samples, we investigate the application of deep learning in predicting the detailed morphologies of galaxies in Euclid using Zoobot, a convolutional
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Bright unintended electromagnetic radiation from second-generation Starlink satellites Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-18 C. G. Bassa, F. Di Vruno, B. Winkel, G. I. G. Józsa, M. A. Brentjens, X. Zhang
We report on the detection of unintended electromagnetic radiation (UEMR) from the second-generation of Starlink satellites. Observations with the LOFAR radio telescope between 10 to 88 MHz and 110 to 188 MHz show broadband emission covering the frequency ranges from 40 to 70 MHz and 110 to 188 MHz from the v2-Mini and v2-Mini Direct-to-Cell Starlink satellites. The spectral power flux density of this
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Detection prospects of very and ultra high-energy gamma rays from extended sources with ASTRI, CTA, and LHAASO Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-18 S. Celli, G. Peron
Context. The recent discovery of several ultra high-energy gamma-ray emitters in our Galaxy represents a significant advancement towards the characterisation of its most powerful accelerators. Nonetheless, in order to unambiguously locate the regions where the highest energy particles are produced and understand the responsible physical mechanisms, detailed spectral and morphological studies are required
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Magnetic helicity and energy budgets of jet events from an emerging solar active region Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-18 A. Nindos, S. Patsourakos, K. Moraitis, V. Archontis, E. Liokati, M. K. Georgoulis, A. A. Norton
Using photospheric vector magnetograms obtained by the Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory and a magnetic connectivity-based method, we computed the magnetic helicity and free magnetic energy budgets of a simple bipolar solar active region (AR) during its magnetic flux-emergence phase, which lasted ∼47 h. The AR did not produce any coronal mass ejections (CMEs) or
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A multi-wavelength study of Galactic H II regions with extended emission Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-17 Jyotirmoy Dey, Jagadheep D. Pandian, Dharam V. Lal, Michael R. Rugel, Andreas Brunthaler, Karl M. Menten, Friedrich Wyrowski, Nirupam Roy, Sergio A. Dzib, Sac-Nicté X. Medina, Sarwar Khan, Rohit Dokara
Context. H II regions are the signposts of massive (M ≥ 8 M⊙) star-forming sites in our Galaxy. It has been observed that the ionizing photon rate inferred from the radio continuum emission of H II regions is significantly lower (~90%) than that inferred from far-infrared fluxes measured by the Infrared Astronomical Satellite.Aims. This discrepancy in the ionizing photon rates may arise due to there
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Mapping the exo-Neptunian landscape Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-17 A. Castro-González, V. Bourrier, J. Lillo-Box, J.-B. Delisle, D. J. Armstrong, D. Barrado, A. C. M. Correia
Context. Atmospheric and dynamical processes are thought to play a major role in shaping the distribution of close-in exoplanets. A striking feature of such distribution is the Neptunian desert, a dearth of Neptunes on the shortest-period orbits.Aims. We aimed to define the boundaries of the Neptunian desert and study its transition into the savanna, a moderately populated region at larger orbital
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Sulfur monoxide (SO) as a shock tracer in protoplanetary disks: Case of AB Aurigae Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-17 A. Dutrey, E. Chapillon, S. Guilloteau, Y. W. Tang, A. Boccaletti, L. Bouscasse, T. Collin-Dufresne, E. Di Folco, A. Fuente, V. Piétu, P. Rivière-Marichalar, D. Semenov
Context. Sulfur monoxide (SO) is known to be a good shock tracer in molecular clouds and protostar environments, but its abundance is difficult to reproduce, even with state-of-the-art astrochemical models.Aims. We investigate the properties of the observed SO emission in the protoplanetary disk of AB Auriga, a Herbig Ae star of 2.4 M⊙ in mass, located at 156 pc. The AB Aur system is unique because
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Discs are born eccentric Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-17 Benoît Commerçon, Francesco Lovascio, Elliot Lynch, Enrico Ragusa
Context. Recent observations have begun probing the early phases of disc formation, but little data yet exists on disc structure and morphology of Class 0 objects. Using simulations, we are able to lay out predictions of disc morphologies expected in future surveys of young discs. Based on detailed simulations of ab initio star formation by core collapse, we predict that early discs must be eccentric
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K2-399 b is not a planet Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-17 J. Lillo-Box, D. W. Latham, K. A. Collins, D. J. Armstrong, D. Gandolfi, E. L. N. Jensen, A. Castro-González, O. Balsalobre-Ruza, B. Montesinos, S. G. Sousa, J. Aceituno, R. P. Schwarz, N. Narita, A. Fukui, J. Cabrera, A. Hadjigeorghiou, M. Kuzuhara, T. Hirano, M. Fridlund, A. P. Hatzes, O. Barragán, N. M. Batalha
Context. The transit technique has been very efficient over the past decades in detecting planet-candidate signals. The so-called statistical validation approach has become a popular way of verifying a candidate’s planetary nature. However, the incomplete consideration of false-positive scenarios and data quality can lead to misinterpretation of the results.Aims. In this work, we revise the planetary
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Plasma wave survey from Parker Solar Probe observations during Venus gravity assists Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-13 H. George, D. M. Malaspina, D. Lee-Bellows, L. C. Gasque, K. Goodrich, Y. Ma, S. Curry
Context. Parker Solar Probe (PSP) performs Venus gravity assists (VGAs) in order to lower its perihelion. PSP takes high-cadence electric and magnetic field observations during these VGAs, providing the opportunity to study plasma waves in Venus’s induced magnetosphere.Aims. We summarize the plasma environment during these VGAs, including the regions of near-Venus space that PSP traversed and the key
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The mass distribution of stellar mergers Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-13 N. Dvořáková, D. Korčáková, F. Dinnbier, P. Kroupa
Context. FS CMa stars belong to a diverse group of stars exhibiting the B[e] phenomenon, which manifests itself mainly by the presence of forbidden emission lines and a strong infrared (IR) excess in their spectra. Only a few tens of FS CMa stars are known and their nature is still unclear. Recently, a strong magnetic field has been discovered in the FS CMa star IRAS 17449+2320. Its strength combined
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Demographics of tidal disruption events with L-Galaxies Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-13 M. Polkas, S. Bonoli, E. Bortolas, D. Izquierdo-Villalba, A. Sesana, L. Broggi, N. Hoyer, D. Spinoso
Stars can be ripped apart by tidal forces in the vicinity of a massive black hole (MBH), causing luminous flares known as tidal disruption events (TDEs). These events could be contributing to the mass growth of intermediate-mass MBHs. New samples from transient surveys can provide useful information on this unexplored growth channel. This work aims to study the demographics of TDEs by modeling the
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The effect of the environment-dependent stellar initial mass function on the photometric properties of star-forming galaxies Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-13 Moritz Haslbauer, Zhiqiang Yan, Tereza Jerabkova, Eda Gjergo, Pavel Kroupa, Akram Hasani Zonoozi
Context. Observational estimates of galaxy properties, including mass and star formation rates (SFRs), rely on the inherent galaxy-wide initial mass function (gwIMF), which systematically varies with the global SFR and metallicity, as proposed by the integrated-galactic IMF (IGIMF) theory and supported by empirical evidence.Aims. We aim to evaluate the influence of the variable gwIMF on various galaxy
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Dynamical evolution of Milky Way globular clusters on the cosmological timescale Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-12 Maryna Ishchenko, Peter Berczik, Taras Panamarev, Dana Kuvatova, Mukhagali Kalambay, Anton Gluchshenko, Oleksandr Veles, Margaryta Sobolenko, Olexander Sobodar, Chingis Omarov
Context. Based on the Gaia DR3, we reconstructed the orbital evolution of the known Milky Way globular clusters and found that six objects, NGC 6681, NGC 6981, Palomar 6, NGC 6642, HP 1, and NGC 1904, very likely interact closely with the nuclear star cluster.Aims. We study the dynamical evolution of selected Milky Way globular clusters and their interactions with the Galactic centre over cosmological
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DIES: Parallel dust radiative transfer program with the immediate re-emission method Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-12 Mika Juvela
Context. Radiative transfer (RT) modelling is a necessary tool in the interpretation of observations of the thermal emission of interstellar dust. It is also often part of multi-physics modelling. In this context, the efficiency of radiative transfer calculations is important, even for one-dimensional models.Aims. We investigate the use of the so-called immediate re-emission (IRE) method for fast calculation
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Ultraviolet spectroscopy of the supernova Ia hypervelocity runaway white dwarf J0927−6335 Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-11 Klaus Werner, Kareem El-Badry, Boris T. Gänsicke, Ken J. Shen
The hot white dwarf (WD) J0927−6335 (Gaia DR3 5250394728194220800 with an effective temperature of Teff = 60 000 K and a surface gravity of logg = 7) was detected as the fastest known Galactic hypervelocity star with a space velocity of ≈2800 km s−1 and an atmosphere dominated by carbon and oxygen. It is thought to be the surviving WD donor predicted by the so-called dynamically driven double-degenerate
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Impact of stellar population synthesis choices on forward modelling-based redshift distribution estimates Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-10 Luca Tortorelli, Jamie McCullough, Daniel Gruen
Context. The forward modelling of galaxy surveys has recently gathered interest as one of the primary methods to achieve the required precision on the estimate of the redshift distributions for stage IV surveys, allowing them to perform cosmological tests with unprecedented accuracy. One of the key aspects of forward modelling a galaxy survey is the connection between the physical properties drawn
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The interplay between disk wind and magnetospheric accretion mechanisms in the innermost environment of RU Lup Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-06 J. A. Wojtczak, B. Tessore, L. Labadie, K. Perraut, J. Bouvier, C. Dougados, H. Nowacki, A. Soulain, E. Alécian, G. Pantolmos, J. Ferreira, C. Straubmeier, A. Eckart
Context. Hydrogen recombination lines such as Brγ are tracers of hot gas within the inner circumstellar disk of young stellar objects (YSOs). In the relatively cool innermost environment of T Tauri stars specifically, Brγ emission is closely associated with magnetically driven processes, such as magnetospheric accretion. Magnetospheric emission alone would arise from a relatively compact region that
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The properties and kinematics of HCN emission across the closest starburst galaxy NGC 253 observed with ALMA Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-06 I. Bešlić, A. T. Barnes, F. Bigiel, M. J. Jiménez-Donaire, A. Usero, J. D. Henshaw, C. Faesi, A. K. Leroy, E. Rosolowsky, J. S. den Brok, M. Chevance, C. Eibensteiner, K. Grasha, R. S. Klessen, J. M. D. Kruijssen, D. Liu, S. Meidt, J. Neumann, L. Neumann, H. Pan, J. Puschnig, M. Querejeta, E. Schinnerer, T. G. Williams
Context. Investigating molecular gas tracers, such as hydrogen cyanide (HCN), to probe higher densities than CO emission across nearby galaxies remains challenging. This is due to the large observing times required to detect HCN at a high sensitivity and spatial resolution. Although approximate kiloparsec scales of HCN maps are available for tens of galaxies, higher-resolution maps still need to be
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ESPRESSO reveals blueshifted neutral iron emission lines on the dayside of WASP-76 b★ Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-05 A. R. Costa Silva, O. D. S. Demangeon, N. C. Santos, D. Ehrenreich, C. Lovis, H. Chakraborty, M. Lendl, F. Pepe, S. Cristiani, R. Rebolo, M. R. Zapatero-Osorio, V. Adibekyan, Y. Alibert, R. Allart, C. Allende Prieto, T. Azevedo Silva, F. Borsa, V. Bourrier, E. Cristo, P. Di Marcantonio, E. Esparza-Borges, P. Figueira, J. I. González Hernández, E. Herrero-Cisneros, G. Lo Curto, C. J. A. P. Martins,
Context. Ultra hot Jupiters (gas giants with Teq > 2000 K) are intriguing exoplanets due to the extreme physics and chemistry present in their atmospheres. Their torrid daysides can be characterised using ground-based high-resolution emission spectroscopy.Aims. We search for signatures of neutral and singly ionised iron (Fe I and Fe II, respectively) in the dayside of the ultra hot Jupiter WASP-76
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Exocomet orbital distribution around β Pictoris Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-05 René Heller
The ~23 Myr young star β Pictoris (β Pic) is a laboratory for planet formation studies because of its observed debris disk, its directly imaged super-Jovian planets β Pic b and c, and the evidence of extrasolar comets that regularly transit in front of the star. The most recent evidence of exocometary transits around β Pic came from stellar photometric time series obtained with the TESS space mission
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The 𝒯ℛ𝒪𝒴 project Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-03 O. Balsalobre-Ruza, J. Lillo-Box, D. Barrado, A. C. M. Correia, J. P. Faria, P. Figueira, A. Leleu, P. Robutel, N. Santos, E. Herrero-Cisneros
Context. Co-orbital objects, also known as trojans, are frequently found in simulations of planetary system formation. In these configurations, a planet shares its orbit with other massive bodies. It is still unclear why there have not been any co-orbitals discovered thus far in exoplanetary systems (exotrojans) or even pairs of planets found in such a 1:1 mean motion resonance. Reconciling observations
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Into the depths: Unveiling ELAIS-N1 with LOFAR’s deepest sub-arcsecond wide-field images Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-03 J. M. G. H. J. de Jong, R. J. van Weeren, F. Sweijen, J. B. R. Oonk, T. W. Shimwell, A. R. Offringa, L. K. Morabito, H. J. A. Röttgering, R. Kondapally, E. L. Escott, P. N. Best, M. Bondi, H. Ye, J. W. Petley
We present the deepest wide-field 115–166 MHz image at sub-arcsecond resolution spanning an area of 2.5° × 2.5° centred at the ELAIS-N1 deep field. To achieve this, we improved the direction-independent (DI) and direction-dependent (DD) calibrations for the International LOw Frequency ARray (LOFAR) Telescope. This enhancement enabled us to efficiently process 32 h of data from four different 8-h observations
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Symbiotic stars in X-rays Astron. Astrophys. (IF 5.4) Pub Date : 2024-09-03 I. J. Lima, G. J. M. Luna, K. Mukai, A. S. Oliveira, J. L. Sokoloski, F. M. Walter, N. Palivanas, N. E. Nuñez, R. R. Souza, R. A. N. Araujo
White dwarf symbiotic binaries are detected in X-rays with luminosities in the range of 1030–1034 ergs s−1. Their X-ray emission arises either from the accretion disk boundary layer, from a region where the winds from both components collide, or from nuclear burning on the surface of the white dwarf (WD). In our continuous effort to identify X-ray-emitting symbiotic stars, we studied four systems using
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Impediments to the cosmic growth of galaxies: The outflow budget from Star Formation and Active Galactic Nuclei Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 Johannes Buchner
The gas reservoir of galaxies can be altered by outflows that are driven by star formation and luminous active galactic nuclei. Jets heating the surroundings of host galaxies can also prevent the gas from cooling and prevent inflows. Spectacular examples for these three mass-displacement channels have been observed, but their importance in transforming the galaxy population depends on the occurrence
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Weighing Milky Way and Andromeda in an expanding ΛCDM Universe Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 David Benisty
The dynamics of the Local Group (LG), especially the contribution of the Milky Way (MW) and Andromeda (M 31) galaxies, is sensitive to the presence of dark energy. This work analyzes the evolution of the LG by considering it as a two-body problem in a homogeneous and isotropic expanding spacetime in a full Λcold dark matter (ΛCDM) background. Using the timing argument (TA), which links LG dynamics
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PDRs4All Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 J. R. Goicoechea, J. Le Bourlot, J. H. Black, F. Alarcón, E. A. Bergin, O. Berné, E. Bron, A. Canin, E. Chapillon, R. Chown, E. Dartois, M. Gerin, E. Habart, T. J. Haworth, C. Joblin, O. Kannavou, F. Le Petit, T. Onaka, E. Peeters, J. Pety, E. Roueff, A. Sidhu, I. Schroetter, B. Tabone, A. G. G. M. Tielens, B. Trahin, D. Van De Putte, S. Vicente, M. Zannese
The gas-phase abundance of carbon, xC = [C/H]gas = xC+ + xC0 + xCO + … , and its depletion factors are essential parameters for understanding the gas and solid compositions that are ultimately incorporated into (exo)planets. The majority of protoplanetary disks are born in clusters and, as a result, are exposed to external far-ultraviolet (FUV) radiation. These FUV photons potentially affect the disk’s
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Gas-rich “ultra-diffuse” galaxies are consistent with the baryonic Tully–Fisher relation and with Milgromian dynamics Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 F. Lelli
Some gas-rich “ultra-diffuse” galaxies (UDGs), which are extreme examples of low surface brightness (LSB) dwarf galaxies, have been reported to lack dark matter and to be offset from the baryonic Tully–Fisher relation (BTFR). If confirmed, these UDGs would represent a serious challenge for both ΛCDM galaxy-formation models and Milgromian dynamics. Here I demonstrate that these conclusions are very
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FAUST Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 M. J. Maureira, J. E. Pineda, H. B. Liu, L. Testi, D. Segura-Cox, C. Chandler, D. Johnstone, P. Caselli, G. Sabatini, Y. Aikawa, E. Bianchi, C. Codella, N. Cuello, D. Fedele, R. Friesen, L. Loinard, L. Podio, C. Ceccarelli, N. Sakai, S. Yamamoto
Context. Planets form in the disks surrounding young stars. The time at which the planet formation process begins is still an open question. Annular substructures such as rings and gaps in disks are intertwined with planet formation, and thus their presence or absence is commonly used to investigate the onset of this process.Aims. Current observations show that a limited number of disks surrounding
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X-Shooting ULLYSES: Massive stars at low metallicity Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-30 A. A. C. Sander, J.-C. Bouret, M. Bernini-Peron, J. Puls, F. Backs, S. R. Berlanas, J. M. Bestenlehner, S. A. Brands, A. Herrero, F. Martins, O. Maryeva, D. Pauli, V. Ramachandran, P. A. Crowther, V. M. A. Gómez-González, A. C. Gormaz-Matamala, W.-R. Hamann, D. J. Hillier, R. Kuiper, C. J. K. Larkin, R. R. Lefever, A. Mehner, F. Najarro, L. M. Oskinova, E. C. Schösser, T. Shenar, H. Todt, A. ud-Doula
Context. The spectral analysis of hot, massive stars is a fundamental astrophysical method of determining their intrinsic properties and feedback. With their inherent, radiation-driven winds, the quantitative spectroscopy for hot, massive stars requires detailed numerical modeling of the atmosphere and an iterative treatment in order to obtain the best solution within a given framework.Aims. We present
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Search for rotating radio transients in three years of monitoring data Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-27 S. A. Tyul’bashev, M. A. Kitaeva, D. V. Pervoukhin, G. E. Tyul’basheva, E. A. Brylyakova, A. V. Chernosov, I. L. Ovchinnikov
The search for rotating radio transients (RRATs) was carried out at a frequency of 111 MHz, as daily observations carried out on the Large Phased Array (LPA) radio telescope at declinations of −9° < δ < +42°. Overall, 19 new RRATs were discovered for dispersion measures (DMs) from 2.5 to 72.6 pc cm−3. Estimates of the periods were obtained for three RRATs, with two of them (J0408+28; J0440+35) located
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Intrinsic line profiles for X-ray fluorescent lines in SKIRT Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-23 Bert Vander Meulen, Peter Camps, Masahiro Tsujimoto, Keiichi Wada
Context. X-ray microcalorimeter instruments are expected to spectrally resolve the intrinsic line shapes of the strongest fluorescent lines. X-ray models should therefore incorporate these intrinsic line profiles to obtain meaningful constraints from observational data.Aims. We included the intrinsic line profiles of the strongest fluorescent lines in the X-ray radiative transfer code SKIRT to model
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Climate change in hell: Long-term variation in transits of the evaporating planet K2-22b Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-23 E. Gaidos, H. Parviainen, E. Esparza-Borges, A. Fukui, K. Isogai, K. Kawauchi, J. de Leon, M. Mori, F. Murgas, N. Narita, E. Palle, N. Watanabe
Context. Rocky planets on ultra-short period orbits can have surface magma oceans and rock-vapour atmospheres in which dust can condense. Observations of that dust can inform us about the composition and surface conditions on these objects.Aims. We constrained the properties and long-term (decade) behaviour of the transiting dust cloud from the evaporating planet K2-22b.Methods.We observed K2-22b around
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Straight outta photosphere: Open solar flux without coronal modeling Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 Ismo Tähtinen, Timo Asikainen, Kalevi Mursula
Context. The open solar flux, that is, the total magnetic flux escaping the Sun, is one of the most important parameters connecting solar activity to the Earth. The open solar flux is commonly estimated from photospheric magnetic field measurements by making model assumptions about the solar corona. However, the question in which way the open solar flux is directly related to the distribution of the
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The giant outburst of EXO 2030+375 Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 R. Ballhausen, P. Thalhammer, P. Pradhan, E. Sokolova-Lapa, J. Stierhof, K. Pottschmidt, J. Wilms, J. B. Coley, P. Kretschmar, F. Fürst, P. Becker, B. West, C. Malacaria, M. T. Wolff, R. Rothschild, R. Staubert
In 2021, the high-mass X-ray binary EXO 2030+375 underwent a giant X-ray outburst, the first since 2006, that reached a peak flux of ∼600 mCrab (3–50 keV). The goal of this work is to study the spectral evolution over the course of the outburst, search for possible cyclotron resonance scattering features (CRSFs), and to associate spectral components with the emission pattern of the accretion column
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The giant outburst of EXO 2030+375 Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 P. Thalhammer, R. Ballhausen, E. Sokolova-Lapa, J. Stierhof, A. Zainab, R. Staubert, K. Pottschmidt, J. B. Coley, R. E. Rothschild, G. K. Jaisawal, B. West, P. A. Becker, P. Pradhan, P. Kretschmar, J. Wilms
The Be X-ray binary EXO 2030+375 went through its third recorded giant outburst from June 2021 to early 2022. We present the results of both spectral and timing analysis based on NICER monitoring, covering the 2−10 keV flux range from 20 to 310 mCrab. Dense monitoring with observations carried out about every second day and a total exposure time of ∼160 ks allowed us to closely track the source evolution
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The rich interstellar reservoir of dinitriles: Detection of malononitrile and maleonitrile in TMC-1⋆ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 M. Agúndez, C. Bermúdez, C. Cabezas, G. Molpeceres, Y. Endo, N. Marcelino, B. Tercero, J.-C. Guillemin, P. de Vicente, J. Cernicharo
While the nitrile group is by far the most prevalent one among interstellar molecules, the existence of interstellar dinitriles (molecules containing two −CN groups) has recently been proven. Here we report the discovery of two new dinitriles in the cold dense cloud TMC-1. These newly identified species are malononitrile, CH2(CN)2, and maleonitrile, the Z isomer of NC−CH=CH−CN, which can be seen as
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Rotational state-to-state transition rate coefficients for H2O + H2O collisions at nonequilibrium conditions Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 Bikramaditya Mandal, Michal Zoltowski, Martin Cordiner, Francois Lique, Dmitri Babikov
Aims. The goal is to develop a database of rate coefficients for rotational state-to-state transitions in H2O + H2O collisions that is suitable for the modeling of energy transfer in nonequilibrium conditions, in which the distribution of rotational states of H2O deviates from local thermodynamic equilibrium.Methods. A two-temperature model was employed that assumed that although there is no equilibrium
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The updated BOSZ synthetic stellar spectral library★ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-22 Szabolcs Mészáros, Ralph Bohlin, Carlos Allende Prieto, Borbála Cseh, József Kovács, Scott W. Fleming, Zoltán Dencs, Susana Deustua, Karl D. Gordon, Ivan Hubeny, György Mező, Márton Truszek
Context. The modeling of stellar spectra of flux standards observed by the Hubble and James Webb space telescopes requires a large synthetic spectral library that covers a wide atmospheric parameter range.Aims. The aim of this paper is to present and describe the calculation methods behind the updated version of the BOSZ synthetic spectral database, which was originally designed to fit the CALSPEC
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Assessing the residual biases in high-resolution transit absorption spectra correction Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-21 W. Dethier, B. Tessore
Context. In recent years it has become common practice to divide observed transit absorption spectra by synthetic absorption spectra computed for the transit of an atmosphere-less planet. This action supposedly corrects the observed absorption spectrum, leaving the sole atmospheric absorption signature free from the biases induced by stellar rotation and centre-to-limb variations.Aims. We aim to show
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Understanding the star formation efficiency in dense gas: Initial results from the CAFFEINE survey with ArTéMiS★ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-20 M. Mattern, Ph. André, A. Zavagno, D. Russeil, H. Roussel, N. Peretto, F. Schuller, Y. Shimajiri, J. Di Francesco, D. Arzoumanian, V. Revéret, C. De Breuck
Context. Despite recent progress, the question of what regulates the star formation efficiency (SFE) in galaxies remains one of the most debated problems in astrophysics. According to the dominant picture, star formation (SF) is regulated by turbulence and feedback, and the SFE is ~1–2% or less per local free-fall time on all scales from Galactic clouds to high-redshift galaxies. In an alternate scenario
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Tracking Advanced Planetary Systems (TAPAS) with HARPS-N Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-20 G. Maciejewski, A. Niedzielski, K. Goździewski, A. Wolszczan, E. Villaver, M. Fernández, M. Adamów, J. Sierzputowska
Aims. The star HD 118203, classified as a K0 subgiant, was known to harbour a transiting hot Jupiter planet on a 6.1-day eccentric orbit. Previous studies also revealed a linear trend in the radial velocity (RV) domain, indicative of a companion on a wide orbit. Such a hierarchical orbital architecture could be helpful in studies of the origins of hot Jupiters.Methods. We acquired precise RV measurements
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Peering above the clouds of the warm Neptune GJ 436 b with CRIRES+ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-20 Natalie Grasser, Ignas A. G. Snellen, Rico Landman, Darío González Picos, Siddharth Gandhi
Context. Exoplanets with masses between Earth and Neptune are amongst the most commonly observed, yet their properties are poorly constrained. Their transmission spectra are often featureless, which indicate either high-altitude clouds or a high atmospheric metallicity. The archetypical warm Neptune GJ 436 b is such a planet showing a flat transmission spectrum in observations with the Hubble Space
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Space and laboratory discovery of iminopentadienylidene, HNC5⋆ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-15 R. Fuentetaja, C. Cabezas, Y. Endo, M. Agúndez, B. Tercero, N. Marcelino, P. de Vicente, J. Cernicharo
We report the discovery of HNC5 in TMC-1. Six lines have been found in harmonic relation, with quantum numbers J = 12−11 up to J = 17−16. The lines can be reproduced with the standard frequency relation for linear molecules with B = 1361.75034 ± 0.00033 MHz and D = 32.2 ± 0.7 Hz. The assignment of the carrier to iminopentadienylidene was achieved through examining the possible candidates at a high
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Early emission lines in SN 2024ggi revealed by high-resolution spectroscopy Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-15 Thallis Pessi, Régis Cartier, Emilio Hueichapan, Danielle de Brito Silva, Jose L. Prieto, Ricardo R. Muñoz, Gustavo E. Medina, Paula Diaz, Ting S. Li
Context. We present an analysis of very early high-resolution spectroscopic observations of the Type II supernova (SN) 2024ggi, a nearby SN that occurred in the galaxy NGC 3621 at a distance of 7.24 Mpc (z ≈ 0.002435). These observations represent the earliest high-resolution spectra of a Type II SN ever made.Aims. We analyzed the very early-phase spectroscopic evolution of SN 2024ggi obtained in a
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Ultrasoft state of microquasar Cygnus X-3: X-ray polarimetry reveals the geometry of the astronomical puzzle Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-14 Alexandra Veledina, Juri Poutanen, Anastasiia Bocharova, Alessandro Di Marco, Sofia V. Forsblom, Fabio La Monaca, Jakub Podgorný, Sergey S. Tsygankov, Andrzej A. Zdziarski, Varpu Ahlberg, David A. Green, Fabio Muleri, Lauren Rhodes, Stefano Bianchi, Enrico Costa, Michal Dovčiak, Vladislav Loktev, Michael McCollough, Paolo Soffitta, Rashid Sunyaev
Cygnus X-3 is an enigmatic X-ray binary that is both an exceptional accreting system and a cornerstone for population synthesis studies. Prominent X-ray and radio properties follow a well-defined pattern, and yet the physical reasons for the state changes observed in this system are not known. Recently, the presence of an optically thick envelope around the central source in the hard state was revealed
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The rich galactic environment of a H2-absorption-selected quasar Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-14 F. Urbina, P. Noterdaeme, T. A. M. Berg, S. Balashev, S. López, F. Bian
We present the first Very Large Telescope (VLT) Multi Unit Spectroscopic Explorer (MUSE) observations of a quasar featuring a proximate molecular absorption system, SDSS J125917.31+030922.5. The proximate damped Lyα absorption acts as a natural coronagraph, removing the quasar emission over ∼40 Å in wavelength, and allows us to detect extended Lyα emission without the necessity of subtracting the quasar
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Damping wings in the Lyman-α forest: A model-independent measurement of the neutral fraction at 5.4 < z < 6.1 Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-14 Benedetta Spina, Sarah E. I. Bosman, Frederick B. Davies, Prakash Gaikwad, Yongda Zhu
Context. Recent observations have positioned the end point of the Epoch of Reionization (EoR) at a redshift of z ∼ 5.3. However, observations of the Lyman-α forest have not yet been able to discern whether reionization occurred slowly and late, with substantial neutral hydrogen persisting at a redshift of ∼6, or rapidly and earlier, with the apparent late end driven by the fluctuating ultraviolet background
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Rotational synchronisation of B-type binaries in 30 Doradus Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-13 D. J. Lennon, P. L. Dufton, J. I. Villaseñor, N. Langer, C. J. Evans, H. Sana, W. D. Taylor
The spin evolution of stars in close binary systems can be strongly affected by tides. We investigate the rotational synchronisation of the stellar components for 69 SB1 systems and 14 SB2 B-type systems in the 30 Doradus region of the Large Magellanic Cloud using observations from the VFTS and BBC surveys. Their orbital periods range from a few to a few hundred days, while estimated primary masses
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Multi-transition study of methanol towards NGC 1068 with ALMA Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-13 K.-Y. Huang, D. Abbink, S. Viti, S. García-Burillo
Context. The outflowing molecular gas in the circumnuclear disc (CND) of the nearby (D = 14 Mpc) AGN-starburst composite galaxy NGC 1068 is considered as a manifestation of ongoing AGN feedback. The large spread of velocities from the outflowing gas is likely driving various kinds of shock chemistry across the CND.Aims. We performed a multiline molecular study using CH3OH with the aim of characterizing
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X-Shooting ULLYSES: Massive stars at low metallicity Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-09 H. Sana, F. Tramper, M. Abdul-Masih, R. Blomme, K. Dsilva, G. Maravelias, L. Martins, A. Mehner, A. Wofford, G. Banyard, C. L. Barbosa, J. Bestenlehner, C. Hawcroft, D. John Hillier, H. Todt, C. J. K. Larkin, L. Mahy, F. Najarro, V. Ramachandran, M. C. Ramírez-Tannus, M. M. Rubio-Díez, A. A. C. Sander, T. Shenar, J. S. Vink, F. Backs, S. A. Brands, P. Crowther, L. Decin, A. de Koter, W.-R. Hamann,
Context. The XShootU project aims to obtain ground-based optical to near-infrared spectroscopy of all targets observed by the Hubble Space Telescope (HST) under the Director’s Discretionary program ULLYSES. Using the medium-resolution spectrograph X-shooter, spectra of 235 OB and Wolf-Rayet (WR) stars in subsolar metallicity environments have been secured. The bulk of the targets belong to the Large
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Confronting sparse Gaia DR3 photometry with TESS for a sample of around 60 000 OBAF-type pulsators★★★ Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-08 Daniel Hey, Conny Aerts
Context. The Gaia mission has delivered hundreds of thousands of variable star light curves in multiple wavelengths. Recent work demonstrates that these light curves can be used to identify (non-)radial pulsations in OBAF-type stars, despite their irregular cadence and low light curve precision, of the order of a few millimagnitudes. With the considerably more precise TESS photometry, we revisited
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A new understanding of the Gemini-Monoceros X-ray enhancement from discoveries with eROSITA Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-09 J. R. Knies, M. Sasaki, W. Becker, T. Liu, G. Ponti, P. P. Plucinsky
Aims. The Gemini-Monoceros X-ray enhancement is a rich field for studying diffuse X-ray emission and supernova remnants (SNRs). Most SNRs in this part of the sky are notoriously difficult to observe due to their large extent. With the launch of the extended ROentgen Survey with an Imaging Telescope Array (eROSITA) on board the Spektrum-Röntgen-Gamma platform in 2019, we are now able to fully study
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Non-thermal radio emission in Sakurai’s Object Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-09 M. Hajduk, P. A. M. van Hoof, A. A. Zijlstra, G. Van de Steene, S. Kimeswenger, D. Barría, D. Tafoya, J. A. Toalá
Context. The very late thermal pulse (VLTP) affects the evolution of ∼20% of 1–8 M⊙ stars, repeating the last red giant phases within a few years and leading to the formation of a new, but hydrogen-poor, nebula within the old planetary nebula. The strong dust formation in the latter obscures the optical and near-infrared radiation of the star.Aims. We aimed to determine the reheating timescale of the
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Self-similar cluster structures in massive star-forming regions: Isolated evolution from clumps to embedded clusters Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-12 Jian-wen Zhou, Pavel Kroupa, Sami Dib
We used the dendrogram algorithm to decompose the surface density distributions of stars into hierarchical structures. These structures were tied to the multiscale structures of star clusters. A similar power-law for the mass-size relation of star clusters measured at different scales suggests a self-similar structure of star clusters. We used the minimum spanning tree method to measure the separations
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Asteroid (4337) Arecibo: Two ice-rich bodies forming a binary Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-13 Ziyu Liu, Daniel Hestroffer, Josselin Desmars, Pedro David
Context. Binary asteroids are present in all populations of the Solar System, from near-Earth to trans-Neptunian regions. As is true for the small Solar System bodies (SSSBs), binary asteroids generally offer valuable insights into the formation of the Solar System, as well as its collisions and dynamic evolution. In particular, the binaries provide fundamental quantities and properties of these SSSBs
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Secular aberration drift in stellar proper motions Astron. Astrophys. (IF 5.4) Pub Date : 2024-08-12 N. Liu, Z. Zhu, J.-C. Liu
Context. The motion of the Solar System barycenter (SSB), the spatial origin of the International Celestial Reference System, causes a directional displacement known as secular aberration. The secular aberration drift caused by the galactocentric acceleration of the SSB has been modeled in the third generation of the International Celestial Reference Frame.Aims. We aim to address another secular aberration