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The mass-metallicity relation at z ≳ 3 down to M⋆≃ 104 M⊙ Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
M. Bellazzini, T. Muraveva, A. GarofaloThe mass-metallicity relation (MZR) is a fundamental scale law of galaxies. It is observed to evolve with redshift in unresolved galaxies up to z > 6. However, observational constraints limits our view at such early epochs to galaxies with M⋆ ≳ 107 M⊙. On the other hand, in the local Universe the MZR can be traced down to the faintest end of the galaxy luminosity function (M⋆ ≃ 102 M⊙) but we have
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Multiple stellar populations in MOCCA globular cluster models: Transient spatial overconcentration of pristine red giant stars driven by strong dynamical encounters Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
M. Giersz, A. Askar, A. Hypki, J. Hong, G. Wiktorowicz, L. HellströmRecent findings show that, in some Milky Way globular clusters (GCs), pristine red giant branch (RGB) stars are more centrally concentrated than enriched ones. This contradicts most multiple-population formation scenarios, which predict that the enriched population (2P) should initially be more concentrated than the pristine population (1P). We analyzed a MOCCA GC model that exhibits a higher spatial
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A neural network approach to determining photometric metallicities of M-type dwarf stars Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
C. Duque-Arribas, H. M. Tabernero, D. Montes, J. A. Caballero, E. GalceranContext. M dwarfs are the most abundant stars in the Galaxy and serve as key targets for stellar and exoplanetary studies. It is particularly challenging to determine their metallicities because their spectra are complex. For this reason, several authors have focused on photometric estimates of the M-dwarf metallicity. Although artificial neural networks have been used in the framework of modern astrophysics
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Supermassive black hole mass measurement in the spiral galaxy NGC 4736 using JWST/NIRSpec stellar kinematics Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
Dieu D. Nguyen, Hai N. Ngo, Tinh Q. T. Le, Alister W. Graham, Roberto Soria, Igor V. Chilingarian, Niranjan Thatte, N. T. Phuong, Thiem Hoang, Miguel Pereira-Santaella, Mark Durre, Diep N. Pham, Le Ngoc Tram, Nguyen B. Ngoc, Ngân LêWe present accurate mass measurements of the central supermassive black hole (SMBH) in NGC 4736 (M 94). We used the “gold-standard” stellar absorption features (CO band heads) at ∼2.3 μm, as opposed to gas emission lines, to trace the dynamics in the nuclear region, easily resolving the SMBH’s sphere of influence. The analysis uses observations made with the integral field unit of the Near-Infrared
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The role of stellar model input in correcting the asteroseismic scaling relations Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
G. Valle, M. Dell’Omodarme, P. G. Prada Moroni, S. Degl’InnocentiAims. This study investigates the variability of the theoretical correction factor, fΔν, used in red giant branch (RGB) scaling relations, arising from different assumptions in stellar model computations.Methods. Adopting a commonly used framework, we focused on a 1.0 M⊙ star and systematically varied seven input parameters: the reference solar mixture, the initial helium abundance, the inclusion of
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Polarimetric insights into a potential binary supermassive black hole system in Mrk 231 Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
J. Biedermann, F. Marin, T. BarnouinContext. Markarian 231 (Mrk 231) is one of the brightest ultraluminous infrared galaxies (ULIRGs) known to date. It displays a unique optical-ultraviolet (optical-UV) spectrum, characterized by a strong and perplexing attenuation in the near-UV, associated with a sudden polarization peak.Aims. The aim of this study is to clarify the puzzling nature of Mrk 231’s spectrum by examining the potential existence
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Multifrequency simultaneous VLBA view of the radio source 3C 111 Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
V. Bartolini, D. Dallacasa, J. L. Gómez, M. Giroletti, R. Lico, J. D. LivingstonContext. Relativistic jets originating at the center of active galactic nuclei are embedded in extreme environments with strong magnetic fields and high particle densities, which makes them a fundamental tool for studying the physics of magnetized plasmas.Aims. We aim to investigate the magnetic field structure and the parsec and sub-parsec properties of the relativistic jet in the radio galaxy 3C
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Quantifying the detectability of Milky Way satellites with image simulations: Case study with KiDS Astron. Astrophys. (IF 5.4) Pub Date : 2025-06-03
Shiyang Zhang, Hendrik Hildebrandt, Ziang Yan, Simon E. T. Smith, Massimiliano Gatto, Massimo Dall’Ora, Crescenzo Tortora, Shun-Sheng Li, Dominik ElsässerUltra-faint dwarf galaxies, which can be detected as resolved satellite systems of the Milky Way, are critical to our understanding of galaxy formation, evolution, and the nature of dark matter, as they are the oldest, smallest, most metal-poor, and most dark matter-dominated stellar systems known thus far. Quantifying the sensitivity of surveys is essential to investigating their capability and limitations
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Edge-on galaxies relative to the edge-on view of the Local Supercluster Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-29
P. Dolgosheeva, D. Makarov, N. LibeskindCosmological theories suggest that the angular momentum of galaxies is closely linked to the structure of the cosmic web. The Local Supercluster is the closest and most frequently studied structure in which the orientation of galaxy spins can be studied. As noted previously, the use of edge-on galaxies greatly simplifies this task by reducing the task to an analysis of the position angle distribution
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A post-common-envelope binary with double-peaked Balmer emission lines from TMTS Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-29
Qichun Liu, Xiaofeng Wang, Jie Lin, Chengyuan Wu, Chunqian Li, Alexei V. Filippenko, Thomas G. Brink, Yi Yang, Weikang Zheng, Cheng Liu, Cuiying Song, Mikhail Kovalev, Hongwei Ge, Fenghui Zhang, Xiaobin Zhang, Qiqi Xia, Haowei Peng, Gaobo Xi, Jun Mo, Shengyu Yan, Jianrong Shi, Jiangdan Li, Tuan YiContext. The dynamical method provides an efficient way to discover post-common-envelope binaries (PCEBs) with faint white dwarfs (WDs), thanks to the development of time-domain survey projects. As close binary systems undergo a common-envelope phase, they offer unique opportunities to study the astrophysical processes associated with binary evolution.Aims. We perform a comprehensive analysis of the
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Study of the 2024 major Vela glitch at the Argentine Institute of Radioastronomy Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Ezequiel Zubieta, Ryan Missel, Susana B. Araujo Furlan, Carlos O. Lousto, Federico García, Santiago del Palacio, Guillermo Gancio, Jorge A. Combi, Linwei WangContext. We report here on new results of the systematic monitoring of southern glitching pulsars at the Argentine Institute of Radioastronomy. In particular, we study in this work the new major glitch in the Vela pulsar (PSR J0835−4510) that occurred on 2024 April 29.Aims. We aim to thoroughly characterise the rotational behaviour of the Vela pulsar around its last major glitch and investigate the
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The Pristine Dwarf-Galaxy survey Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Nicolas Longeard, Pascale Jablonka, Giuseppina Battaglia, Khyati Malhan, Nicolas F. Martin, Julio F. Navarro, Federico SestitoAims. The Milky Way has a large population of dwarf galaxy satellites. Their properties are sensitive to both cosmology and the physical processes underlying galaxy formation, but these properties are still not properly characterised for the entire satellite population.Methods. We aim to provide the most accurate systemic dynamical and metallicity properties of the dwarf galaxy Boötes II (Boo II).Results
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Tidal interaction can stop galactic bars: On the LMC non-rotating bar Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Ó. Jiménez-Arranz, S. Roca-FàbregaContext. The bar pattern speed of the LMC has been computed based on data from Gaia DR3 using three different methods. One method suggested that the LMC might be hosting a bar that barely rotates, and is slightly counter-rotating with respect to the disc of the LMC, with a pattern speed of Ωp = −1.0 ± 0.5 km s−1 kpc−1.Aims. We aim to confirm that tidal interactions might prevent the bar hosted by the
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V4141 Sgr: Outflows and repeated outbursts Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Jaroslav Merc, Joanna Mikołajewska, Thomas Petit, Berto Monard, Stéphane Charbonnel, Olivier Garde, Pascal Le Dû, Lionel Mulato, Tadashi KojimaIn this work, we analyze the ongoing brightening of the poorly studied symbiotic star V4141 Sgr and examine its long-term variability. We present new low-resolution spectroscopic observations of the system in its bright state and combine them with multi-color photometric data from our observations, as well as ASAS-SN, ATLAS, and Gaia DR3. To investigate its long-term evolution, we also incorporated
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Driven two-fluid Alfvén waves in a solar magnetic flux tube with a realistic ionization rate Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
J. Kraśkiewicz, K. MurawskiContext. This study was performed in the context of the chromosphere and low corona heating.Aims. We considered the evolution of driven Alfvén waves in the solar atmosphere, whose initial state was modeled with a realistic ionization profile. We discuss their potential role in plasma heating.Methods. Two- and half-dimensional (2.5 D) numerical simulations of the solar atmosphere were performed with
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Line-of-sight velocity projection impact on Local Group mass determinations Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
David Benisty, David MotaThe mass of the Local Group (LG), which includes the Milky Way, Andromeda (M31), and their satellites, is crucial for validating galaxy formation and cosmological models. Traditional virial mass estimates, which rely on line-of-sight (LoS) velocities and simplified infall assumptions, are prone to systematic biases due to unobserved velocity components and anisotropic kinematics. Using the TNG cosmological
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Discovery of a bimodal luminosity distribution in the persistent Be/X-ray pulsar 2RXP J130159.6–635806 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Alexander Salganik, Sergey S. Tsygankov, Maria Chernyakova, Denys Malyshev, Juri PoutanenWe present a comprehensive analysis of 2RXP J130159.6−635806, a persistent low-luminosity Be/X-ray pulsar, focusing on its transition to a spin equilibrium state and the discovery of a bimodal luminosity distribution that possibly reveals a new accretion regime. Using data from the NuSTAR, Swift, XMM-Newton, and Chandra observatories, we investigated changes in the pulsar’s timing and spectral properties
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Multi-scale exploration of SMACS J0723.3–7327’s intracluster light and past dynamical history Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Amaël EllienWe present an analysis of the intracluster light (ICL) in the galaxy cluster SMACS J0723.3–7327 (hereafter, SMACS J0723) using JWST/NIRCam deep imaging in six filters (F090W to F444W). We processed images for low surface brightness (LSB) science, applying additional corrections for instrumental scattering in the short-wavelength channels. We analysed the images using wavelet-based decomposition and
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SN 2023xqm: A gradually fading Ia supernova exhibiting isolated high-velocity signatures Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Xiangyun Zeng, Yijing Luo, Xiaofeng Wang, Xin Li, Yi Yang, Sheng Zheng, Shuguang Zeng, Yao Huang, Sai Li, D. Andrew Howell, K. Azalee Bostroem, Curtis McCully, Ali Esamdin, Moira Andrews, Joseph R. Farah, Megan Newsome, Haonan Zhang, Peng Zhang, Lei HuWe conducted an exhaustive analysis combining optical photometry and spectroscopy of the type Ia supernova designated SN 2023xqm. Our observational period spanned from the two weeks preceding to 88 days after the B-band peak luminosity time. We determined the peak brightness in the B-band to be −18.90 ± 0.50 mag, and it is accompanied by a moderately slow decay rate of 0.90 ± 0.07 mag. The maximum
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The impact of ram pressure on cluster galaxies, insights from GAEA and TNG Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Lizhi Xie, Gabriella De Lucia, Matteo Fossati, Fabio Fontanot, Michaela HirschmannRam pressure stripping (RPS) has a non-negligible impact on the gas content of cluster galaxies. We used the semi-analytic model GAEA and the hydro-simulation TNG to investigate whether cluster galaxies suffer from strong RPS that is sufficient to remove a significant fraction of their gas during the first pericentric passage. We estimated that a ram pressure of 10−10.5, 10−12, 10−13.5g cm−1 s−2 can
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Quasi-periodic pulsations in extreme-ultraviolet brightenings Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Daye Lim, Tom Van Doorsselaere, David Berghmans, Laura A. Hayes, Cis Verbeeck, Nancy Narang, Marie Dominique, Andrew R. InglisContext. Extreme-ultraviolet (EUV) observations have revealed small-scale transient brightenings that may be caused by the same physical mechanisms as larger-scale solar flares. A notable feature of solar and stellar flares is the presence of quasi-periodic pulsations (QPPs), which are a potentially intrinsic characteristic.Aims. We investigated the properties of QPPs detected in EUV brightenings,
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Enhancing MHD model accuracy and CME forecasting by constraining coronal plasma properties with Faraday rotation Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
Salvatore MancusoAccurate forecasting and modeling of coronal mass ejections (CMEs) and their associated shocks are pivotal for understanding space weather and its impact on Earth. This requires a detailed understanding of CMEs’ 3D morphology and the properties of the pre-eruption coronal plasma, which are usually inferred from global 3D numerical magnetohydrodynamic (MHD) simulations. Refining MHD models is thus crucial
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Cyclic variability of the accretion disk in the eclipsing binary OGLE-LMC-DPV-065 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-28
R. E. Mennickent, G. DjuraševićContext. The long photometric cycle observed in Algol OGLE-LMC-DPV-065 (OGLE05200407-6936391), and other similar systems, still challenges explanation. It is currently thought that a variable mass transfer rate could modify the structure of the accretion disk surrounding the more massive star, producing modulations of the global system brightness.Aims. We revisited I-band Optical Gravitational Lensing
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Formation and nature of “Huntsman” binary pulsars Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-27
O. G. Benvenuto, M. A. De Vito, M. Echeveste, M. L. Novarino, N. D. Pires, L. M. de Sá, J. E. HorvathContext. “Spider” systems are a class of close binaries in which a neutron star first accretes from a normal companion, and later ablates it in some cases. New observations have expanded this category, with the addition of a “Huntsman” group, tentatively linked to a short donor phase along the red bump along the secondary evolutionary track.Aims. We present here explicit evolutionary tracks that support
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Gravitational instability and spatial regularity of the gas clouds and young stellar population in spiral arms of NGC 628 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-27
V. S. Kostiuk, A. S. Gusev, A. A. Marchuk, E. V. ShimanovskayaContext. There is a clear contradiction between the characteristic spacings in observed regular chains of star-forming regions in the spiral arms of galaxies (∼500 pc) and the estimates of the wavelength of gravitational instability in them (> 1 kpc).Aims. We aim to calculate the scales of regularity in the grand-design galaxy NGC 628 in terms of gravitational instability by using modern high-quality
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Feasibility of interferometric observations and characterization of planet-induced structures at sub au to au scales in protoplanetary disks Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-27
L. Hildebrandt, A. Krieger, H. Klahr, J. Kobus, A. Bensberg, S. WolfContext. Interferometric observations of protoplanetary disks by VLTI and ALMA have greatly improved our understanding of the detailed structure of these planetary birthplaces. These observations have revealed a variety of large-scale disk substructures, including rings, gaps, and spirals, spanning tens to hundreds of au, supporting the predictions of planet formation models. Recent instruments, such
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viper: High-precision radial velocities from the optical to the infrared Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-27
J. Köhler, M. Zechmeister, A. Hatzes, S. Chamarthi, E. Nagel, U. Seemann, P. Ballester, P. Bristow, P. Chaturvedi, R. J. Dorn, E. Guenther, V. D. Ivanov, Y. Jung, O. Kochukhov, T. Marquart, L. Nortmann, R. Palsa, N. Piskunov, A. Reiners, F. Rodler, J. V. SmokerContext. High-precision radial velocity (RV) measurements with slit spectrographs require the instrument profile (IP) and Earth’s atmospheric spectrum to be known and to be incorporated into the RV calculation.Aims. We developed an RV pipeline, called Velocity and IP EstimatoR (viper), to achieve high-precision RVs in the near-infrared (NIR). The code is able to process observations taken with a gas
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Exploring the halo-galaxy connection with probabilistic approaches Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-23
Natália V. N. Rodrigues, Natalí S. M. de Santi, Raul Abramo, Antonio D. Montero-DortaContext. The connection between galaxies and their host dark matter halos encompasses a range of intricate and interrelated processes, playing a pivotal role in our understanding of galaxy formation and evolution. Traditionally, this link has been established through physical or empirical models. On the other hand, machine learning techniques are adaptable tools capable of handling high-dimensional
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Rotation and dispersion measure evolution of repeating fast radio bursts propagating through a magnetar’s flare ejecta Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
Di XiaoRotation measure (RM) and dispersion measure (DM) are characteristic properties of fast radio bursts (FRBs) that contain important information of their source environment. The time evolution of the RM and DM is more inclined to be ascribed to local plasma in the host galaxy, rather than the intergalactic medium or free electrons in the Milky Way. A sudden, drastic RM change was recently reported for
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Zooming into the neutrino-associated blazar candidate J1718+4239 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
K. Perger, S. Frey, K. É. Gabányi, E. KunThe radio quasar NVSS J171822+423948 (J1718+4239) was proposed to be the counterpart of the IceCube neutrino event IC-201221A. To reveal the nature of the source, we conducted new very long baseline interferometry observations of this blazar candidate with the Very Long Baseline Array. The observations were carried out in dual-band mode between 4 and 7 GHz. Archival radio data from the literature were
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Unraveling the origin of giant exoplanets Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-23
H. Knierim, R. HelledThe connection between the atmospheric composition of giant planets and their origin remains elusive. In this study, we explore how convective mixing can link the primordial planetary state to its atmospheric composition. We simulate the long-term evolution of gas giants with masses between 0.3 and 3 MJ, considering various composition profiles and primordial entropies (assuming no entropy-mass dependence)
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Comprehensive UV and optical spectral analysis of Cygnus X-1 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
V. Ramachandran, A. A. C. Sander, L. M. Oskinova, E. C. Schösser, D. Pauli, W.-R. Hamann, L. Mahy, M. Bernini-Peron, M. Brigitte, B. KubátováContext. Cygnus X-1 contains the only dynamically confirmed black hole in a persistent high-mass X-ray binary in the Milky Way. Previous studies have suggested that the black hole in Cyg X-1 is one of the most massive stellar-mass black holes known in an X-ray binary, despite its high-metallicity environment. While the source has been actively investigated, a comprehensive UV and optical spectral analysis
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Ray-tracing GR-MHD-generated outflows from AGNs hosting thin accretion disks Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-23
Bidisha Bandyopadhyay, Christian Fendt, Dominik R. G. Schleicher, Neil M. Nagar, Felipe Agurto-Sepúlveda, Javier PedrerosContext. Active galactic nuclei (AGNs) exhibit a wide range of black hole masses and inflow/outflow properties. It is now possible to probe regions close to the event horizons of nearby supermassive black holes (SMBHs) using very long baseline interferometry (VLBI) with earth-sized baselines, as performed by the Event Horizon Telescope (EHT).Aims. This study explores the emission properties of accretion
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Radio study of the colliding-wind binary HD 93129A near periastron and its surroundings Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
P. Benaglia, S. del Palacio, J. Saponara, A. B. Blanco, M. De Becker, B. MarcoteContext. HD 93129A is an O+O stellar system whose colliding-wind region (CWR) has been mapped by high angular resolution observations at centimetre wavelengths. The synchrotron nature of the radio emission confirms its particle accelerator status. Astrometric measurements since 1996 indicate that the system has an orbital period of ~120 yr and recently went through its periastron passage.Aims. We attempted
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Combining summary statistics with simulation-based inference for the 21 cm signal from the Epoch of Reionisation Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
B. Semelin, R. Mériot, A. Mishra, D. CornuThe 21 cm signal from the Epoch of Reionisation will be observed with the upcoming Square Kilometer Array (SKA). We expect it to yield a full tomography of the signal, which opens up the possibility to explore its non-Gaussian properties. This raises the question of how can we extract the maximum information from tomography and derive the tightest constraint on the signal. In this work, instead of
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Revisiting the energy distribution and formation rate of CHIME fast radio bursts Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
K. J. Zhang, Z. B. Zhang, A. E. Rodin, V. A. Fedorova, Y. F. Huang, D. Li, X. F. Dong, P. Wang, Q. M. Li, C. Du, F. Xu, C. T. HaoBased on the first CHIME/FRB catalogue, three volume-limited samples of fast radio bursts (FRBs) are built, with samples 1, 2, and 3 corresponding to a fluence cut of 5, 3, and 1, respectively. The Lynden-Bell’s c− method was applied to study their energy function and event rate evolution with redshift (z). Using the non-parametric Kendall’s τ statistics, it is found that the FRB energy (E) strongly
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Dust-void evolution driven by turbulent dust flux can induce runaway migration of Earth-mass planets Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-26
R. O. Chametla, O. Chrenko, F. S. Masset, G. D’Angelo, D. NesvornýTorques from asymmetric dust structures (so-called dust-void and filamentary structures) formed around low-mass planets embedded in a nonturbulent dust-gas disk can exceed the torques produced by the gas disk component and then go on to dominate the planet’s orbital dynamics. Here, we investigate how these structures (hence the dust torque) change when the effect of turbulent dust diffusion and dust
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The quest for high-redshift radio galaxies Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-22
Alessandro Capetti, Barbara Balmaverde, Miguel Coloma Puga, Bruno Vizzone, Ana Jimenez-Gallardo, Abigail García-Pérez, Giacomo VenturiThe population of high-redshift radio galaxies (HzRGs) is still poorly studied because only a few of these objects are currently known. We here present the results of a pilot project of spectroscopic identification of HzRG candidates. The candidates are selected by combining low-frequency radio and optical surveys that cover a total of ∼2000 deg2 using the dropout technique, that is, the presence of
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The stellar corona-chromosphere connection Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-22
S. Freund, S. Czesla, B. Fuhrmeister, P. Predehl, J. Robrade, P. C. Schneider, J. H. M. M. SchmittStellar activity can be observed at different wavelengths in a variety of different activity indicators. We investigated the correlation between coronal and chromospheric emissions by combining X-ray data from stars detected in the eROSITA all-sky surveys (eRASS1 and eRASS:5) with Ca II infrared triplet (IRT) activity indices as published in the third Gaia data release (Gaia DR3). We specifically studied
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Anomalous cross-field motions of solar coronal loops Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-22
Sudip Mandal, Hardi Peter, James A. Klimchuk, Lakshmi Pradeep ChittaWe present several examples of unusual evolutionary patterns in solar coronal loops that resemble cross-field drift motions. These loops were simultaneously observed from two vantage points by two different spacecraft: the High-Resolution Imager of the Extreme Ultraviolet Imager aboard the Solar Orbiter and the Atmospheric Imaging Assembly aboard the Solar Dynamics Observatory. Across all these events
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Optical observations of the peculiar high-mass X-ray binary 4U 2206+54 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-22
K. A. Stoyanov, M. Moyseev, Y. M. Nikolov, R. K. Zamanov, G. Y. Latev, K. Iłkiewicz, V. HambaryanContext. We present results from the high-resolution optical spectroscopy and spectropolarimetry of the peculiar high-mass X-ray binary 4U 2206+54.Aims. We aim to estimate the size of the circumstellar disc and investigate the interaction between the compact object and the matter in the disc. We also study the interstellar polarisation towards 4U 2206+54.Methods. We performed a periodogram analysis
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The mass distribution of stars stripped in binaries: The effect of metallicity Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-22
B. Hovis-Afflerbach, Y. Götberg, A. Schootemeijer, J. Klencki, A. L. Strom, B. A. Ludwig, M. R. DroutStars stripped of their hydrogen-rich envelopes through binary interaction are thought to be responsible for both hydrogen-poor supernovae and the hard ionizing radiation observed in low-Z galaxies. A population of these stars was recently observed for the first time, but their prevalence remains unknown. In preparation for such measurements, we estimate the mass distribution of hot, stripped stars
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Discovery of resonating integration modes in triple-mode high-amplitude δ Scuti stars: A new evolutionary phase indicator Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-20
Jia-Shu Niu, Hui-Fang XueHigh-amplitude δ Scuti stars (HADS) that pulsate in their first three radial modes are rare in current samples. Here, we analyse five such triple-mode HADS observed by the Transiting Exoplanet Survey Satellite (TESS) and report that the previously considered second overtone mode (f2) is actually the non-radial component of a resonating integration mode (RI mode, resulting from resonance between a radial
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Propagation of coronal large-amplitude Alfvén-type waves to the solar photosphere Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-21
I. Živanović, V. V. Smirnova, Yu. T. Tsap, Y. ChenContext. We present a study of the propagation of magnetohydrodynamic (MHD) Alfvén-type waves from the solar corona to the photosphere, generated by the large-amplitude velocity pulse.Aims. We aim to estimate the energy flux and the propagation time of Alfvén-type waves, which can be responsible for the white-light flare emission caused by solar photospheric heating.Methods. The ideal MHD equations
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Size and shape of the trans-Neptunian object (470316) 2007 OC10: Comparison with thermal data Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-19
J. M. Gómez-Limón, R. Leiva, J. L. Ortiz, N. Morales, M. Kretlow, M. Vara-Lubiano, P. Santos-Sanz, A. Álvarez-Candal, J. L. Rizos, R. Duffard, E. Fernández-Valenzuela, Y. Kilic, S. Cikota, B. Sicardy, F. Bragas-Ribas, M. R. Alarcon, S. Aliş, Z. Benkhaldoun, A. Burdanov, J. de Wit, S. Calavia Belloc, J. Calvo Fernández, O. Canales Moreno, G. Catanzaro, S. Fişek, A. Frasca, R. Iglesias-Marzoa, R. Infante-SainzContext. The shapes of only 12 trans-Neptunian objects have been directly measured, offering crucial insights into their internal structure. These properties are strongly connected to the processes that shaped the early Solar System, and provide important clues about its evolution.Aims. The aim of the present work is to characterise the size, shape, geometric albedo, and beaming parameter of the TNO
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Non-halo structures and their effects on gravitationally lensed galaxies Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
Baptiste Jego, Giulia Despali, Tamara Richardson, Jens StückerWhile the lambda cold dark matter (ΛCDM) model is very successful on large scales, its validity on smaller scales remains uncertain. Recent works suggest that non-halo dark matter structures, such as filaments and walls, could significantly influence gravitational lensing and that the importance of these effects depends on the dark matter model. Specifically, in warm dark matter (WDM) scenarios, fewer
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High energy time lags of gamma-ray bursts Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
C. Maraventano, G. Ghirlanda, L. Nava, T. Di Salvo, W. Leone, R. Iaria, L. Burderi, A. TsvetkovaContext. Positive lags between the arrival time of different photon energies are commonly observed in the prompt phase of gamma-ray bursts (GRBs), where soft photons lag behind harder ones. However, a fraction of GRBs display the opposite behavior. In particular, Fermi Large Area Telescope (LAT) observations revealed that high-energy photons are often characterized by a delayed onset.Aims. We explore
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Detection of J-band photometric periodicity in the T8 dwarfs 2MASS J09393548-2448279 and EQ J1959-3338 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
P. A. Miles-Páez, S. Metchev, M. R. Zapatero Osorio, D. Martín-CarreroAims. We aim to study the near-infrared variability of the T8 dwarfs 2MASS J09393548-2448279 and EQ J1959-3338 by analyzing their J-band photometric signal, which can provide new insights into the atmospheric dynamics of cold brown dwarfs.Methods. We used FLAMINGOS-2 on the Gemini South telescope to perform J-band differential photometry continuously over 4 h for each target. The resulting light curves
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On the limitations of using metric radio bursts as diagnostic tools for interplanetary coronal mass ejections Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
J. Kandekar, A. KumariAims. Metric radio bursts are often said to be valuable diagnostic tools for studying the near-sun kinematics and energetics of the interplanetary coronal mass ejections (ICMEs). Radio observations also serve as indirect tools to estimate the coronal magnetic fields. However, how these estimated coronal magnetic fields are related to the magnetic field strength in the ICME at 1 AU has rarely been explored
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Binary evolution pathways to blue large-amplitude pulsators: Insights from HD 133729 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-19
Zhengyang Zhang, Chengyuan Wu, Xianfei Zhang, Zhanwen Han, Bo WangBlue large-amplitude pulsators (BLAPs) are a recently identified class of pulsating stars distinguished by their short pulsation periods (2–60 minutes) and asymmetric light curves. This study investigated the evolutionary channel of HD 133729, which is the first confirmed BLAP in a binary system. Using the binary evolution code MESA, we explored various mass ratios and initial orbital periods. Our
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Exploring the connection between atmosphere models and evolution models of very massive stars Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
J. Josiek, A. A. C. Sander, M. Bernini-Peron, S. Ekström, G. González-Torà, R. R. Lefever, N. Moens, V. Ramachandran, E. C. SchösserContext. Very massive stars (VMSs) are stars that are born with masses of more than 100 M⊙. Despite their rarity, their dominance in the integrated light of young stellar populations and their strong stellar feedback make them worthwhile objects of study. Their evolution is dominated by mass loss, rather than interior processes, which underlines the significance of an accurate understanding of their
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Abell548: A rich cluster of galaxies in the making⋆ Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
Hernán Quintana, Dominique Proust, Ivan Lacerna, Hans Böhringer, Gayoung ChonWe performed an in-depth study of the complex structure of the galaxy cluster A548, based on 108 spectroscopic galaxy velocities reported in this paper. This analysis includes 80 new redshifts, along with velocity data from the literature and a reanalysis of X-ray observations. We find that the cluster is in a merging phase of at least six components. These belong to two sheets, or clouds, of galaxies
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Simulation of the distribution of radio pulsar nulling fractions Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-19
R. YuenAims. In this work, we aim to simulate the observed distribution of the pulse nulling fractions (NFs) in radio pulsars and to investigate the associated properties of the emission region.Methods. We identified three conditions related to the occurrence of pulse nulling. From the traditional approach for correlation of the pulsed radio intensity and plasma density, a pulse cessation results from switching
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Search for γ-ray emission from supernova remnants in the Large Magellanic Cloud: A new cluster analysis at energies above 4 GeV Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-19
A. Tramacere, R. Campana, E. Massaro, F. Bocchino, M. Miceli, S. OrlandoContext. A search for γ-ray emission from supernova remnants (SNRs) in the Large Magellanic Cloud (LMC) based on the detection of concentrations in the arrival direction Fermi-LAT images of photons at energies higher than 10 GeV found significant evidence for nine sources. This analysis was based on data collected in the time window from August 4, 2008, to August 4, 2020 (12 years).Aims. In the present
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X-ray polarization observations of NGC 2110 with IXPE Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-16
I. Pal, S. Marchesi, N. Torres-Albà, I. Cox, M. Ajello, A. Banerjee, R. Silver, A. Pizzetti, K. ImamContext. X-ray polarimetric observations from the Imaging X-ray Polarimeter Explorer (IXPE) is an excellent tool for probing the geometry and dynamics of X-ray emitting corona in active galactic nuclei (AGNs).Aims. This work aims to investigate the geometry of the X-ray corona in the Seyfert 2 AGN, NGC 2110, using its first polarimetric observation with IXPE, conducted over a net exposure of 554 ks
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The tidal heating of the exoplanet 55 Cnc e Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-15
Sylvio Ferraz-Mello, Cristian BeaugéContext. Observations with warm Spitzer and JWST have revealed a high and variable brightness in the planet 55 Cnc e.Aims. Our aim is to make an inventory of the tidal effects on the rotational and orbital evolution of the planet 55 Cnc e enhanced by the nonzero orbital eccentricity.Methods. The creep-tide theory is used in simulations and dynamical analyses that explore the difficult trapping of the
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Fine-scale opposite-polarity magnetic fields in a solar plage revealed by integral field spectropolarimetry Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-14
G. Liu, I. Milić, J. S. Castellanos Durán, J. M. Borrero, M. van Noort, C. KuckeinContext. Plages are small concentrations of strong, nearly vertical magnetic fields in the solar photosphere that expand with height. A high spatial and spectral resolution that can resolve their fine structure is required to characterize them, and spectropolarimetric capabilities are needed to infer their magnetic fields.Aims. We constrain the 3D fine structure of the magnetic field in the photosphere
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Accuracy of the ‘tip of the red giant branch’ distance determination method Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-14
Vladas VansevičiusContext. To solve the so-called Hubble tension problem, highly accurate methods of determining extragalactic distances are needed. Therefore, the accuracy and applicability of the tip of the red giant branch (TRGB) method is of the utmost importance.Aims. In this work, we aim to study variations in the TRGB versus radial distance and location in the M 33 galaxy disc.Methods. We used colour-magnitude
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Double-peaked Ca II traces a relativistic broad-line region disk in NGC 4593 Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-14
M. W. Ochmann, P. M. Weilbacher, M. A. Probst, W. Kollatschny, D. Chelouche, R. Chini, D. Grupe, M. Haas, S. Kaspi, S. KomossaContext. Double-peaked emission lines are observed in a small percentage of active galactic nuclei (AGN). These lines allow the determination of fundamental properties of the line-emitting region, known as the broad-line region (BLR).Aims. We investigated the structure and kinematics of the BLR in the nearby Seyfert galaxy NGC 4593 through an analysis of the near-infrared (NIR) line blend of Ca IIλ8498
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Tuning into the spatial frequency space Astron. Astrophys. (IF 5.4) Pub Date : 2025-05-13
J. P. Carvajal, F. E. Bauer, I. Reyes-Jainaga, F. Förster, A. M. Muñoz Arancibia, M. Catelan, P. Sánchez-Sáez, C. Ricci, A. BayoContext. A significant challenge in the study of transient astrophysical phenomena is the identification of bogus events, among which human-made Earth-orbiting satellites and debris remain major contaminants. Existing pipelines can effectively identify satellite trails, but they often miss more complex signatures, such as collections of satellite glints. In the Rubin Observatory era, the scale of operations