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Impacts of Energetic Particles from T Tauri Flares on Inner Protoplanetary Discs Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 V Brunn, Ch Rab, A Marcowith, C Sauty, M Padovani, C Meskini
T Tauri stars are known to be magnetically active stars subject to strong flares observed in X-rays. These flares are likely due to intense magnetic reconnection events during which a part of the stored magnetic energy is converted into kinetic energy of supra-thermal particles. Since T Tauri stars are surrounded by an accretion disc, these particles may influence the disc dynamics and chemistry. This
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ExoMol line lists – LVIII. High-temperature molecular line list of carbonyl sulphide (OCS) Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Alec Owens, Sergei N Yurchenko, Jonathan Tennyson
A new molecular line list covering wavelengths λ > 1 μm (the 0 – 10 000 cm−1 range) for the main isotopologue of carbonyl sulphide 16O12C32S is presented. The OCS line list, named OYT8, contains almost 2.5 billion transitions between 2.4 million rotation-vibration energy levels with the total angular momentum up to J = 223. It is suitable for high-temperature environments up to T = 2000 K. Line list
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A JWST investigation into the bar fraction at redshifts 1 ≤ z ≤ 3 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Zoe A Le Conte, Dimitri A Gadotti, Leonardo Ferreira, Christopher J Conselice, Camila de Sá-Freitas, Taehyun Kim, Justus Neumann, Francesca Fragkoudi, E Athanassoula, Nathan J Adams
The presence of a stellar bar in a disc galaxy indicates that the galaxy hosts in its main part a dynamically settled disc and that bar-driven processes are taking place in shaping its evolution. Studying the cosmic evolution of the bar fraction in disc galaxies is therefore essential to understand galaxy evolution in general. Previous studies have found, using the Hubble Space Telescope (HST), that
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Electron-capture supernovae in NS+He star systems and the double neutron star systems Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Yun-Lang Guo, Bo Wang, Wen-Cong Chen, Xiang-Dong Li, Hong-Wei Ge, Long Jiang, Zhan-Wen Han
Electron-capture supernovae (EC-SNe) provide an alternative channel for producing neutron stars (NSs). They play an important role in the formation of double NS (DNS) systems and the chemical evolution of galaxies, and contribute to the NS mass distribution in observations. It is generally believed that EC-SNe originate from e-captures on $\rm ^{24}Mg$ and $\rm ^{20}Ne$ in the massive degenerate oxygen-neon
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Photometric Re-calibration of VPHAS+ u-band photometry with the stellar colour regression method and gaia DR3 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Bing-Qiu Chen, Hai-Bo Yuan, Bo-Wen Huang
The u band magnitude is vital for determining stellar parameters and investigating specific astronomical objects. However, flux calibration in the u band for stars in the Galactic disk presents significant challenges. In this study, we introduce a comprehensive re-calibration of u-band photometric magnitudes of the VPHAS+ Data Release 4 (DR4), employing the Stellar Colour Regression (SCR) technique
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Iterative removal of sources to model the turbulent electromotive force Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Abhijit B Bendre, Jennifer Schober, Prasun Dhang, Kandaswamy Subramanian
We describe a novel method to compute the components of dynamo tensors from direct magnetohydrodynamic (MHD) simulations. Our method relies upon an extension and generalisation of the standard Högbom CLEAN algorithm widely used in radio astronomy to systematically remove the impact of the strongest beams onto the corresponding image. This generalisation, called the Iterative Removal of Sources (IROS)
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ΛCDM not dead yet: Massive high-z Balmer break galaxies are less common than previously reported Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Guillaume Desprez, Nicholas S Martis, Yoshihisa Asada, Marcin Sawicki, Chris J Willott, Adam Muzzin, Roberto G Abraham, Maruša Bradač, Gabe Brammer, Vicente Estrada-Carpenter, Kartheik G Iyer, Jasleen Matharu, Lamiya Mowla, Gaël Noirot, Ghassan T E Sarrouh, Victoria Strait, Rachel Gledhill, Gregor Rihtaršič
Early JWST observations that targeted so-called double-break sources (attributed to Lyman and Balmer breaks at z > 7), reported a previously unknown population of very massive, evolved high-redshift galaxies. This surprising discovery led to a flurry of attempts to explain these objects’ unexpected existence including invoking alternatives to the standard ΛCDM cosmological paradigm. To test these early
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The effect of thermal torques on AGN disc migration traps and gravitational wave populations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Evgeni Grishin, Shmuel Gilbaum, Nicholas C Stone
Accretion discs in active galactic nuclei (AGNs) foster black hole (BH) formation, growth, and mergers. Stellar mass BHs migrate inwards under the influence of hydrodynamical torques unless they encounter a region where the torque flips sign. At these migration traps, BHs accumulate and merge via dynamical or gas-assisted interactions, producing high-frequency LIGO/Virgo/KAGRA (LVK) gravitational wave
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Comparing transit spectroscopy pipelines at the catalogue level: evidence for systematic differences Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Lorenzo V Mugnai, Mark R Swain, Raissa Estrela, Gael M Roudier
The challenge of inconsistent results from different data pipelines, even when starting from identical data, is a recognized concern in exoplanetary science. As we transition into the James Webb Space Telescope (JWST) era and prepare for the ARIEL space mission, addressing this issue becomes paramount because of its implications on our understanding of exoplanets. Although comparing pipeline results
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New evidence of binarity in young α–rich turn-off and subgiant stars: Fast rotation and strong magnetic activity Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-24 Jie Yu, Luca Casagrande, Ioana Ciucă, Yuan-Sen Ting, Simon J Murphy, Boquan Chen
Young α–rich (YAR) stars within the old Galactic thick disk exhibit a dual characteristic of relative youth determined with asteroseismology and abundance enhancement in α elements measured from high–resolution spectroscopy. The youth origin of YAR stars has been proposed to be binary evolution via mass transfer or stellar mergers. If that is the case, YAR stars should spin rapidly and thus be magnetically
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Breakdown of Hawking Evaporation opens new Mass Window for Primordial Black Holes as Dark Matter Candidate Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Valentin Thoss, Andreas Burkert, Kazunori Kohri
The energy injection through Hawking evaporation has been used to put strong constraints on primordial black holes as a dark matter candidate at masses below 1017 g. However, Hawking’s semiclassical approximation breaks down at latest after half-decay. Beyond this point, the evaporation could be significantly suppressed as was shown in recent work. In this study, we review existing cosmological and
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SMARTY: The mileS Moderate resolution neAr-infRared sTellar librarY Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Michele Bertoldo-Coêlho, Rogério Riffel, Marina Trevisan, Natacha Zanon Dametto, Luis Dahmer-Hahn, Paula Coelho, Lucimara Martins, Daniel Ruschel-Dutra, Alexandre Vazdekis, Alberto Rodríguez-Ardila, Ana L Chies-Santos, Rogemar A Riffel, Francesco La Barbera, Ignacio Martín Navarro, Jesus Falcon Barroso, Tatiana Moura
Most of the observed galaxies cannot be resolved into individual stars and are studied through their integrated spectrum using simple stellar populations (SSPs) models, with stellar libraries being a key ingredient in building them. Spectroscopic observations are increasingly being directed towards the near-infrared (NIR), where much is yet to be explored. SSPs in the NIR are still limited, and there
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Constraining the global composition of D/H and 18O/16O in Martian water using SOFIA/EXES Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 J Alday, S Aoki, C DeWitt, F Montmessin, J A Holmes, M R Patel, J P Mason, T Encrenaz, M J Richter, P G J Irwin, F Daerden, N Terada, H Nakagawa
Isotopic ratios in water vapour carry important information about the water reservoir on Mars. Localised variations in these ratios can inform us about the water cycle and surface-atmosphere exchanges. On the other hand, the global isotopic composition of the atmosphere carries the imprints of the long-term fractionation, providing crucial information about the early water reservoir and its evolution
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A large population of neutron star low-mass X-ray binaries with long outburst recurrence time? Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 E Meyer-Hofmeister, Huaqing Cheng, B F Liu
Low-mass X-ray binaries (LMXBs) with neutron stars show quite different features which depend on the rate of mass transfer from the donor star. With a high transfer rate the Z sources are in a persistent soft spectral state, with a moderate rate the transient Atoll sources have outburst cycles like the black hole X-ray binaries. The observations document very long outburst recurrence times for quite
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Improving and extending non-Poissonian distributions for satellite galaxies sampling in HOD: applications to eBOSS ELGs Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Bernhard Vos-Ginés, Santiago Avila, Violeta Gonzalez-Perez, Gustavo Yepes
Halo Occupation Distribution (HOD) models help us to connect observations and theory, by assigning galaxies to dark matter haloes. In this work we study one of the components of HOD models: the probability distribution function (PDF), which is used to assign a discrete number of galaxies to a halo, given a mean number of galaxies. For satellite galaxies, the most commonly used PDF is a Poisson Distribution
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A covariant formulation for cosmological radiative transfer of the 21-cm line Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Jennifer Y H Chan, Qin Han, Kinwah Wu, Jason D McEwen
The 21-cm hyperfine line of neutral hydrogen is a useful tool to probe the conditions of the Universe during the Dark Ages, Cosmic Dawn, and the Epoch of Reionisation. In most of the current calculations, the 21-cm line signals at given frequencies are computed, using an integrated line-of-sight line opacity, with the correction for cosmological expansion. These calculations have not fully captured
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On the properties and implications of collapse-driven MHD turbulence Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Enrique Vázquez-Semadeni, Yue Hu, Siyao Xu, Rubén Guerrero-Gamboa, Alex Lazarian
We investigate the driving of MHD turbulence by gravitational contraction using simulations of an initially spherical, isothermal, magnetically supercritical molecular cloud core with transonic and trans-Alfvénic turbulence. We perform a Helmholtz decomposition of the velocity field, and investigate the evolution of its solenoidal and compressible parts, as well as of the velocity component along the
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Characterising Tidal Features Around Galaxies in Cosmological Simulations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 A Khalid, S Brough, G Martin, L Kimmig, C D P Lagos, R-S Remus, C Martinez-Lombilla
Tidal features provide signatures of recent mergers and offer a unique insight into the assembly history of galaxies. The Vera C. Rubin Observatory’s Legacy Survey of Space and Time (LSST) will enable an unprecedentedly large survey of tidal features around millions of galaxies. To decipher the contributions of mergers to galaxy evolution it will be necessary to compare the observed tidal features
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The formation of transiting circumplanetary debris discs from the disruption of satellite systems during planet–planet scattering Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Alexander J Mustill, Melvyn B Davies, Matthew A Kenworthy
Several stars show deep transits consistent with discs of roughly 1 R⊙ seen at moderate inclinations, likely surrounding planets on eccentric orbits. We show that this configuration arises naturally as a result of planet–planet scattering when the planets possess satellite systems. Planet–planet scattering explains the orbital eccentricities of the discs’ host bodies, while the close encounters during
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Evidence for a nearly orthogonal rotator in GX 301–2 with phase-resolved cyclotron resonant scattering features Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Xiao Chen, Yuanze Ding, Wei Wang, Osamu Nishimura, Qi Liu, Shuang-Nan Zhang, Mingyu Ge, Fangjun Lu, Jinlu Qu, Liming Song, Shu Zhang
Cyclotron resonant scattering features (CRSFs) are the absorption features in the X-ray spectra of strongly magnetized accretion neutron stars (NSs), which are probably the most reliable probe to the surface magnetic fields of NSs. The high mass X-ray binary GX 301–2 exhibits a very wide, variable and complicated CRSF in the average spectra, which should be two absorption lines based on NuStar and
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Modelling stochastic and quasi-periodic behaviour in stellar time-series: Gaussian process regression versus power-spectrum fitting Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Niamh K O’Sullivan, Suzanne Aigrain
As the hunt for an Earth-like exoplanets has intensified in recent years, so has the effort to characterise and model the stellar signals that can hide or mimic small planetary signals. Stellar variability arises from a number of sources, including granulation, supergranulation, oscillations and activity, all of which result in quasi-periodic or stochastic behaviour in photometric and/or radial velocity
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Doppler tomography as a tool for characterising exoplanet atmospheres II: an analysis of HD 179949 b Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 S M Matthews, C A Watson, E J W de Mooij, T R Marsh, M Brogi, S R Merritt, K W Smith, D Steeghs
High-resolution Doppler spectroscopy provides an avenue to study the atmosphere of both transiting and non-transiting planets. This powerful method has also yielded some of the most robust atmospheric detections to date. Currently, high-resolution Doppler spectroscopy detects atmospheric signals by cross-correlating observed data with a model atmospheric spectrum. This technique has been successful
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The impact of cosmic rays on the interstellar medium and galactic outflows of Milky Way analogues Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Francisco Rodríguez Montero, Sergio Martin-Alvarez, Adrianne Slyz, Julien Devriendt, Yohan Dubois, Debora Sijacki
During the last decade, cosmological simulations have managed to reproduce realistic and morphologically diverse galaxies, spanning the Hubble sequence. Central to this success was a phenomenological calibration of the few included feedback processes, whilst glossing over higher complexity baryonic physics. This approach diminishes the predictive power of such simulations, preventing to further our
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Dust-dust collisions in cometary comas: applications to comet 67P/Churyumov-Gerasimenko Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 María Belen Planes, M Gabriela Parisi, Emmanuel N Millán, Eduardo M Bringa, Marcela Cañada-Assandri
Silica has emerged as a crucial component within inner comet comas. This work investigates silica dust aggregates and their interactions within cometary comas. We study the probability that aggregates in the size range 1-100 μm collide with each other in the coma and analyze the outcomes of such collisions by using the “Collision of Porous Aggregates” (CPA) Software, which incorporates mass, size,
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Dynamical Instabilities in Post-Disk Evolution: Hot Jupiters Left Isolated Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Ying He, Dong-Hong Wu, Sheng Jin
The predominant formation channel of hot Jupiters remain a puzzle in exoplanet science. One potential way to distinguish the different mechanisms is to study the characteristics of close-in companions to hot Jupiters. In this study, our main focus is to investigate the post-disk evolution of planetary systems initially composed of one Jupiter and several super-Earths through numerical N-body simulations
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Elucidating the impact of massive neutrinos on halo assembly bias Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Yunjia Song, Ying Zu
Massive neutrinos have non-negligible impact on the formation of large-scale structures. We investigate the impact of massive neutrinos on the halo assembly bias effect, measured by the relative halo bias $\hat{b}$ as a function of the curvature of the initial density peak $\hat{s}$, neutrino excess εν, or halo concentration $\hat{c}$, using a large suite of ΣMν = 0.0 eV and 0.4 eV simulations with
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The S-PLUS fornax project (S+FP): SExtractor detection and measurement of nearby galaxies in large photometric surveys Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 R F Haack, A V Smith Castelli, C Mendes de Oliveira, F Almeida-Fernandes, F R Faifer, A R Lopes, Y Jaffe, R Demarco, C Lima-Dias, L Lomelí-Nuñez, G P Montaguth, W Schoenell, T Ribeiro, A Kanaan
All-sky multi-band photometric surveys represent a unique opportunity of exploring rich nearby galaxy clusters up to several virial radii, reaching the filament regions where pre-processing is expected to occur. These projects aim to tackle a large number of astrophysical topics, encompassing both the galactic and extragalactic fields. In that sense, generating large catalogues with homogeneous photometry
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Hα reverberation mapping from broad-band photometry of dwarf seyfert 1 galaxy NGC 4395 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-23 Huapeng Gu, Xue-Bing Wu, Yuhan Wen, Qinchun Ma, Hengxiao Guo
NGC 4395 is a dwarf Seyfert 1 galaxy with a possible intermediate-mass black hole of several $\rm {10^4}$ solar masses in its center. As a well-studied object, its broad line region size has been measured via H$\rm {\alpha }$ time lag in numerous spectroscopic reverberation mapping (SRM) and narrow-band photometric reverberation mapping (PRM) campaigns. Here we present its H$\rm {\alpha }$ time lag
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Multi-scale accretion in dense cloud cores and the delayed formation of massive stars Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-22 Enrique Vázquez-Semadeni, Gilberto C Gómez, Alejandro González-Samaniego
The formation mechanism of massive stars remains one of the main open problems in astrophysics, in particular the relationship between the mass of the most massive stars, and that of the cores in which they form. Numerical simulations of the formation and evolution of molecular clouds, within which dense cores and stars form self-consistently, show that the core mass increases in time, and also that
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Mitigating bias in deep learning: Training unbiased models on biased data for the morphological classification of galaxies Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-22 Esteban Medina-Rosales, Guillermo Cabrera-Vives, Christopher J Miller
Galaxy morphologies and their relation with physical properties have been a relevant subject of study in the past. Most galaxy morphology catalogs have been labelled by human annotators or by machine learning models trained on human labelled data. Human generated labels have been shown to contain biases in terms of the observational properties of the data, such as image resolution. These biases are
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KAOSS: turbulent, but disc-like kinematics in dust-obscured star-forming galaxies at z ∼ 1.3–2.6 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-22 Jack E Birkin, A Puglisi, A M Swinbank, Ian Smail, Fang Xia An, S C Chapman, Chian-Chou Chen, C J Conselice, U Dudzevičiūtė, D Farrah, B Gullberg, Y Matsuda, E Schinnerer, D Scott, J L Wardlow, P van der Werf
We present spatially resolved kinematics of 27 ALMA-identified dust-obscured star-forming galaxies (DSFGs) at z ∼ 1.3–2.6, as traced by Hα emission using VLT/KMOS near-infrared integral field spectroscopy from the “KMOS-ALMA Observations of Submillimetre Sources” (KAOSS) Large Programme. We derive Hα rotation curves and velocity dispersion profiles for the DSFGs, and find that among the 27 sources
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IGM damping wing constraints on the tail end of reionisation from the enlarged XQR-30 sample Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-22 Bradley Greig, A Mesinger, E Bañados, G D Becker, S E I Bosman, H Chen, F B Davies, V D’Odorico, A-C Eilers, S Gallerani, M G Haehnelt, L Keating, S Lai, Y Qin, E Ryan-Weber, S Satyavolu, F Wang, J Yang, Y Zhu
The attenuation of Lyα photons by neutral hydrogen in the intergalactic medium (IGM) at z ≳ 5 continues to be a powerful probe for studying the epoch of reionisation. Given a framework to estimate the intrinsic (true) Lyα emission of high-z sources, one can infer the ionisation state of the IGM during reionisation. In this work, we use the enlarged XQR-30 sample of 42 high-resolution and high-SNR QSO
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The impact of a top-heavy IMF on the formation and evolution of dark star clusters Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-21 Ali Rostami Shirazi, Hosein Haghi, Akram Hasani Zonoozi, Ahmad Farhani Asl, Pavel Kroupa
The Spitzer instability leads to the formation of a black hole sub-system (BHSub) at the center of a star cluster providing energy to luminous stars (LSs) and increasing their rate of evaporation. When the self-depletion time of the BHSub exceeds the evaporation time of the LSs, a dark star cluster (DSC) will appear. Using the NBODY7 code, we performed a comprehensive set of direct N-body simulations
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Gas-phase hydrogenation of large, astronomically relevant PAH cations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-20 Lijun Hua, Xiaoyi Hu, Junfeng Zhen, Xuejuan Yang
To investigate the gas-phase hydrogenation processes of large, astronomically relevant cationic polycyclic aromatic hydrocarbon (PAH) molecules under the interstellar environments, the ion-molecule collision reaction between six PAH cations and H-atoms is studied. The experimental results show that the hydrogenated PAH cations are efficiently formed, and no even-odd hydrogenated mass patterns are observed
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Cosmological constraints on early dark energy from the full shape analysis of eBOSS DR16 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Rafaela Gsponer, Ruiyang Zhao, Jamie Donald-McCann, David Bacon, Kazuya Koyama, Robert Crittenden, Théo Simon, Eva-Maria Mueller
We evaluate the effectiveness of Early Dark Energy (EDE) in addressing the Hubble tension using the luminous red galaxies (LRGs), quasars (QSOs), and emission line galaxies (ELGs) samples from the completed eBOSS survey. We perform cosmological parameter measurements based on full shape analysis of the power spectrum employing the effective field theory of large-scale structure (EFTofLSS). EDE is known
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Disentangling the anisotropic radio sky: Fisher forecasts for 21cm arrays Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Zheng Zhang, Philip Bull, Katrine A Glasscock
The existence of a radio synchrotron background (RSB) excess is implied by a number of measurements, including excess emission seen by the ARCADE 2 and LWA experiments. Highly sensitive wideband radio arrays, of the kind used to measure the cosmic 21cm signal, provide a promising way to further constrain the RSB excess through its anisotropy, providing additional insight into its origin. We present
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Unravelling the collision scenario of the dissociative galaxy cluster Abell 56 through hydrodynamic simulations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Richards P Albuquerque, Rubens E G Machado, Rogério Monteiro-Oliveira
In galaxy cluster collisions, the gas can be separated from dark matter haloes. Abell 56 displays signatures of a dissociative bullet-like merger with a possible high-inclination angle between the plane of orbit and the sky. Our objective is to provide a comprehensive description of the features observed in the collision scenario of Abell 56. Additionally, we aim to apply a potential weak lensing mass
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Simulated host galaxy analogs of high-z quasars observed with JWST Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Sabrina Berger, Madeline A Marshall, J Stuart B Wyithe, Tiziana di Matteo, Yueying Ni, Stephen M Wilkins
The hosts of two low-luminosity high-z quasars, J2255+0251 and J2236+0032, were recently detected using JWST’s NIRCam instrument. These represent the first high-z quasar host galaxy stellar detections and open a new window into studying high-z quasars. We examine the implications of the measured properties of J2255+0251 and J2236+0032 within the context of the hydrodynamic simulation BlueTides at z
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Apparent correlation between extrinsic and intrinsic flux variations in the first gravitationally lensed quasar Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 L J Goicoechea, V N Shalyapin, A Oscoz
To better understand which sources contribute to optical passband fluxes of Q0957+561, we present and analyse light curves of the doubly imaged gravitationally lensed quasar from its discovery to 2023. After an early microlensing event, the difference light curves (describing delay-corrected flux ratios between the two quasar images) only show prominent microlensing gradients over the last 17 yr. In
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Beyond the Rings: Polar Ring Galaxy NGC 4262 and its Globular Cluster System Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Akhil Krishna R, Sreeja S Kartha, Blesson Mathew
In the context of the hierarchical model of galaxy evolution, polar ring galaxies (PRGs) are considered the intermediate phase between ongoing mergers and quiescent galaxies. This study explores the globular cluster system (GCS) and its properties in the nearest PRG, NGC4262, serving as a pilot investigation to study GCS in nearby PRGs. We utilize wide and deep field observations of the CFHT as part
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Observation of the L5 Kordylewski Dust Cloud with a Portable Imaging Polarimetric Telescope in the Namibian Khomas Highland Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Judit Slíz-Balogh, Attila Mádai, Pál Sári, András Barta, Gábor Horváth
The Kordylewski dust clouds (KDCs) around the L5 and L4 Lagrange points of the Earth-Moon system have been first observed by imaging polarimetry in 2017 and 2022 in a Hungarian astronomical observatory. Due to the non-ideal (almost always hazy, aerosol-polluted) astroclimate of Hungary and the extremely low intensity of dust-scattered sunlight, the polarimetric hunt after both KDCs lasted 2-7 years
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Cosmological parameters estimated from peculiar velocity – density comparisons: calibrating 2M++ Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Amber M Hollinger, Michael J Hudson
Cosmological parameters can be measured by comparing peculiar velocities with those predicted from a galaxy density field. Previous work has tested the accuracy of this approach with N-body simulations, but generally on idealised mock galaxy surveys. However, systematic biases may arise solely due to survey selection effects such as flux-limited samples, edge-effects and complications due to the obscuration
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Insights into the 21 cm field from the vanishing cross-power spectrum at the epoch of reionization Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-19 Kana Moriwaki, Angus Beane, Adam Lidz
The early stages of the Epoch of Reionization, probed by the 21 cm line, are sensitive to the detailed properties and formation histories of the first galaxies. We use 21cmFAST and a simple, self-consistent galaxy model to examine the redshift evolution of the large-scale cross-power spectrum between the 21 cm field and line-emitting galaxies. A key transition in redshift occurs when the 21 cm field
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Discovery of a new IW And-type dwarf nova with both tilted disk and tidal instability Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Yongkang Sun, Xin Li, Qige Ao, Wenyuan Cui, Bowen Zhang, Yang Huang, Jianrong Shi, Linlin Li, Jifeng Liu
IW And-type dwarf novae are anomalous Z Cam stars featured with outbursts happening during standstill states, which are not expected in the standard disk instability model. The physical mechanisms for these variations remain unclear. In this study, we report the discovery of a new candidate IW And-type dwarf nova J0652+2436, identified with its frequent outbursts from the slowly rising standstill states
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Stellar populations and merger rates of Brightest Cluster Galaxies a billion years ago: SDSS MaNGA IFU Spectroscopy Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Louise O V Edwards, Kevin A S J Hamel, Joseph C Shy, Jonathan Hernandez, Priscilla Holguin Luna, Denvir J Higgins, Theo Chawla, Adriana Gavidia, Samuel Cole
We investigate the spectroscopic properties of 85 brightest cluster galaxies (BCGs) and their companions observed with the SDSS MaNGA integral field unit. Galaxy redshifts are between 0.08 < z < 0.15, allowing for a field of view up to 80 kpc × 80 kpc. For the main galaxies: The average age of the BCG cores is 7.66 ± 1.36 Gyr with no significant gradient out to 2 Re; the average metallicity of the
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DanceCam: atmospheric turbulence mitigation in wide-field astronomical images with short-exposure video streams Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Spencer Bialek, Emmanuel Bertin, Sébastien Fabbro, Hervé Bouy, Jean-Pierre Rivet, Olivier Lai, Jean-Charles Cuillandre
We introduce a novel technique to mitigate the adverse effects of atmospheric turbulence on astronomical imaging. Utilizing a video-to-image neural network trained on simulated data, our method processes a sliding sequence of short-exposure (∼0.2s) stellar field images to reconstruct an image devoid of both turbulence and noise. We demonstrate the method with simulated and observed stellar fields,
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The XUV-driven escape of the planets around TOI-431 & ν2 Lupi Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 George W King, Lía R Corrales, Jorge Fernández Fernández, Peter J Wheatley, Isaac Malsky, Ares Osborn, David Armstrong
One of the leading mechanisms invoked to explain the existence of the radius valley is atmospheric mass loss driven by X-ray and extreme-ultraviolet irradiation, with this process stripping the primordial envelopes of young, small planets to produce the observed bimodal distribution. We present an investigation into the TOI-431 and ν2 Lupi planetary systems, both of which host planets either side of
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Missing Metals in DQ Stars; a Compelling Clue to their Origin Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 J Farihi, P Dufour, T G Wilson
White dwarf stars frequently experience external pollution by heavy elements, and yet the intrinsically carbon-enriched DQ spectral class members fail to exhibit this phenomenon, representing a decades-old conundrum. This study reports a high-resolution spectroscopic search for Ca ii in classical DQ white dwarfs, finding that these stars are stunted both in pollution frequency and heavy element mass
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Four changing-look active galactic nuclei found from optical variations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Li-Tao Zhu, Jie Li, Zhongxiang Wang, Ju-Jia Zhang
We report the finding of four changing-look (CL) active galactic nuclei (AGN). We selected these sources due to their potential as interesting targets when considering their relatively-large optical flux variations and related mid-infrared flux variations. To identify their CL feature, we use archival spectra from the Sloan Digital Sky Survey (SDSS) taken at least 8 years ago as well as spectra taken
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hayate: photometric redshift estimation by hybridizing machine learning with template fitting Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Shingo Tanigawa, K Glazebrook, C Jacobs, I Labbe, A K Qin
Machine learning photo-z methods, trained directly on spectroscopic redshifts, provide a viable alternative to traditional template-fitting methods but may not generalize well on new data that deviates from that in the training set. In this work, we present a Hybrid Algorithm for WI(Y)de-range photo-z estimation with Artificial neural networks and TEmplate fitting (hayate), a novel photo-z method that
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Transit spectroscopy of K2-33b with subaru/IRD: Spin-Orbit alignment and tentative atmospheric helium Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Teruyuki Hirano, Eric Gaidos, Hiroki Harakawa, Klaus W Hodapp, Takayuki Kotani, Tomoyuki Kudo, Takashi Kurokawa, Masayuki Kuzuhara, Andrew W Mann, Jun Nishikawa, Masashi Omiya, Takuma Serizawa, Motohide Tamura, Pa Chia Thao, Akitoshi Ueda, Sebastien Vievard
Exoplanets in their infancy are ideal targets to probe the formation and evolution history of planetary systems, including the planet migration and atmospheric evolution and dissipation. In this paper, we present spectroscopic observations and analyses of two planetary transits of K2-33b, which is known to be one of the youngest transiting planets (age ≈8 − 11 Myr) around a pre-main-sequence M-type
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Plasmoid identification and statistics in two-dimensional Harris sheet and GRMHD simulations Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 J T Vos, H Olivares, B Cerutti, M Mościbrodzka
Magnetic reconnection is a ubiquitous phenomenon for magnetized plasma and leads to the rapid reconfiguration of magnetic field lines. During reconnection events, plasma is heated and accelerated until the magnetic field lines enclose and capture the plasma within a circular configuration. These so-called plasmoids could therefore observationally manifest themselves as hot spots, which are associated
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The hierarchical structure of galactic haloes: Differentiating clusters from stochastic clumping with AstroLink Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 William H Oliver, Pascal J Elahi, Geraint F Lewis, Tobias Buck
We present AstroLink, an efficient and versatile clustering algorithm designed to hierarchically classify astrophysically-relevant structures from both synthetic and observational data sets. We build upon CluSTAR-ND, a hierarchical galaxy/(sub)halo finder, so that AstroLink now generates a two-dimensional representation of the implicit clustering structure as well as ensuring that clusters are statistically
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Hydrodynamical simulations of merging galaxy clusters: Giant dark matter particle colliders, powered by gravity Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Ellen L Sirks, David Harvey, Richard Massey, Kyle A Oman, Andrew Robertson, Carlos Frenk, Spencer Everett, Ajay S Gill, David Lagattuta, Jacqueline McCleary
Terrestrial particle accelerators collide charged particles, then watch the trajectory of outgoing debris – but they cannot manipulate dark matter. Fortunately, dark matter is the main component of galaxy clusters, which are continuously pulled together by gravity. We show that galaxy cluster mergers can be exploited as enormous, natural dark matter colliders. We analyse hydrodynamical simulations
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Mapping the Intracluster Medium in the Era of high-resolution X-ray spectroscopy Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 Congyao Zhang, Irina Zhuravleva, Maxim Markevitch, John ZuHone, François Mernier, Veronica Biffi, Ákos Bogdán, Priyanka Chakraborty, Eugene Churazov, Klaus Dolag, Stefano Ettori, William R Forman, Lars Hernquist, Christine Jones, Ildar Khabibullin, Caroline Kilbourne, Ralph Kraft, Erwin T Lau, Sheng-Chieh Lin, Daisuke Nagai, Dylan Nelson, Anna Ogorzałek, Elena Rasia, Arnab Sarkar, Aurora Simionescu
High-resolution spectroscopy in soft X-rays will open a new window to map multiphase gas in galaxy clusters and probe physics of the intracluster medium (ICM), including chemical enrichment histories, circulation of matter and energy during large-scale structure evolution, stellar and black hole feedback, halo virialization, and gas mixing processes. An eV-level spectral resolution, large field-of-view
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Maser flares driven by isothermal shock waves Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-18 M D Gray, S Etoka, B Pimpanuwat, A M S Richards
We use 3D computer modelling to investigate the timescales and radiative output from maser flares generated by the impact of shock-waves on astronomical unit-scale clouds in interstellar and star-forming regions, and in circumstellar regions in some circumstances. Physical conditions are derived from simple models of isothermal hydrodynamic (single-fluid) and C-type (ionic and neutral fluid) shock-waves
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Variabilities in the polar field and solar cycle due to irregular properties of Bipolar Magnetic Regions Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-17 Pawan Kumar, Bidya Binay Karak, Anu Sreedevi
Decay and dispersal of the tilted Bipolar Magnetic Regions (BMRs) on the solar surface are observed to produce the large-scale poloidal field, which acts as the seed for the toroidal field and, thus, the next sunspot cycle. However, various properties of BMR, namely, the tilt, time delay between successive emergences, location, and flux, all have irregular variations. Previous studies show that these
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The Effect of Pulsar Geometry on the Observed Gamma-ray Spectrum of Millisecond Pulsars Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-17 Sheridan J Lloyd, Paula M Chadwick, Anthony M Brown
We analyse 13 yrs of Fermi-LAT pass 8 events from 127 gamma-ray emitting millisecond pulsars (MSPs) in the energy range 0.1−100 GeV and significantly detect 118 MSPs. We fit the stacked emission with a log parabola (LP) spectral model which we show is preferred to two previously published models. We consider the influence of pulsar properties and observer geometric effects on spectral features by defining
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Quasars with flare/eclipse-like variability identified in ZTF Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-17 Zhiyuan Zheng, Yong Shi, Shuowen Jin, H Dannerbauer, Qiusheng Gu, Xin Li, Xiaoling Yu
Active galactic nuclei (AGNs) are known to exhibit optical/UV variability and most of them can be well modeled by the damped random walks. Physical processes that are not related to the accretion disk, such as tidal disruption events (TDE) or moving foreground dusty clouds, can cause flare-like and eclipse-like features in the optical light curve. Both long-term and high-cadence monitoring are needed
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Polarized radio emission of RRAT J1854+0306 Mon. Not. R. Astron. Soc. (IF 4.8) Pub Date : 2024-04-17 Qi Guo, Minzhi Kong, P F Wang, Y Yan, D J Zhou
Polarized radio emission of RRAT J1854+0306 is investigated with single pulses using FAST. Its emission is characterized by nulls, narrow and weak pulses and occasional wide and intense bursts with a nulling fraction of 53.2 per cent. Its burst emission is typically of one rotation, and occasionally of two or three or even 5 rotations at the most, but without significant periodicity. The integrated