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High-resolution Spectroscopic Reconnaissance of a Temperate Sub-Neptune Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-23 Samuel H. C. Cabot, Nikku Madhusudhan, Savvas Constantinou, Diana Valencia, Johanna M. Vos, Thomas Masseron and Connor J. Cheverall
The study of temperate sub-Neptunes is the new frontier in exoplanetary science. A major development in the past year has been the first detection of carbon-bearing molecules in the atmosphere of a temperate sub-Neptune, K2-18 b, a possible Hycean world, with the James Webb Space Telescope (JWST). The JWST is poised to characterize the atmospheres of several other such planets, with important implications
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Stellar Black Holes Can “Stretch” Supermassive Black Hole Accretion Disks Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-23 Shuying Zhou, Mouyuan Sun, Tong Liu, Jian-Min Wang, Jun-Xian Wang and Yongquan Xue
Stellar black holes (sBHs) are widely believed to exist in the accretion disks of active galactic nuclei (AGNs). Previous studies often focus on the transient emission produced by embedded sBHs. Here, we explore the possible observational consequences of an AGN accretion disk that contains a population of accreting sBHs. Embedded accreting sBHs change the effective temperature distribution of the AGN
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Generation of Low-inclination, Neptune-crossing Trans-Neptunian Objects by Planet Nine Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-23 Konstantin Batygin, Alessandro Morbidelli, Michael E. Brown and David Nesvorný
The solar system’s distant reaches exhibit a wealth of anomalous dynamical structure, hinting at the presence of a yet-undetected, massive trans-Neptunian body—Planet Nine (P9). Previous analyses have shown how orbital evolution induced by this object can explain the origins of a broad assortment of exotic orbits, ranging from those characterized by high perihelia to those with extreme inclinations
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Expansion of Accreting Main-sequence Stars during Rapid Mass Transfer Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-23 Mike Y. M. Lau, Ryosuke Hirai, Ilya Mandel and Christopher A. Tout
Accreting main-sequence stars expand significantly when the mass accretion timescale is much shorter than their thermal timescales. This occurs during mass transfer from an evolved giant star onto a main-sequence companion in a binary system and is an important phase in the formation of compact binaries including X-ray binaries, cataclysmic variables, and gravitational-wave sources. In this study,
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Electron Densities of Transition Region Loops Derived from IRIS O iv Spectral Data Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-23 Shiyu Liang, Ziyuan Wang, Zhenghua Huang, Hengyuan Wei, Hui Fu, Ming Xiong and Lidong Xia
Loops are fundamental structures in the magnetized atmosphere of the Sun. Their physical properties are crucial for understanding the nature of the solar atmosphere. Transition region loops are relatively dynamic and their physical properties have not yet been fully understood. With spectral data of the line pair of O iv 1399.8 Å and 1401.2 Å ( K) of 23 transition region loops obtained by IRIS, we
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Tidal Disruption of Planetesimals from an Eccentric Debris Disk Following a White Dwarf Natal Kick Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-22 Tatsuya Akiba, Selah McIntyre and Ann-Marie Madigan
The surfaces of many white dwarfs are polluted by metals, implying a recent accretion event. The tidal disruption of planetesimals is a viable source of white dwarf pollution and offers a unique window into the composition of exoplanet systems. The question of how planetary material enters the tidal disruption radius of the white dwarf is currently unresolved. Using a series of N-body simulations,
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The First Quenched Galaxies: When and How? Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-21 Lizhi Xie, 利智 谢, Gabriella De Lucia, Fabio Fontanot, Michaela Hirschmann, Yannick M. Bahé, Michael L. Balogh, Adam Muzzin, Benedetta Vulcani, Devontae C. Baxter, Ben Forrest, Gillian Wilson, Gregory H. Rudnick, M. C. Cooper and Umberto Rescigno
Many quiescent galaxies discovered in the early Universe by JWST raise fundamental questions on when and how these galaxies became and stayed quenched. Making use of the latest version of the semianalytic model GAEA that provides good agreement with the observed quenched fractions up to z ∼ 3, we make predictions for the expected fractions of quiescent galaxies up to z ∼ 7 and analyze the main quenching
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Evaporation of Close-in Sub-Neptunes by Cooling White Dwarfs Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-21 Elena Gallo, Andrea Caldiroli, Riccardo Spinelli, Federico Biassoni, Francesco Haardt, Mary Anne Limbach, Juliette Becker and Fred C. Adams
Motivated by the recent surge in interest concerning white dwarf (WD) planets, this work presents the first numerical exploration of WD-driven atmospheric escape, whereby the high-energy radiation from a hot/young WD can trigger the outflow of the hydrogen–helium envelope for close-in planets. As a pilot investigation, we focus on two specific cases: a gas giant and a sub-Neptune-sized planet, both
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The Influence of Thermonuclear Bursts on Polar Caps of the Accreting X-Ray Millisecond Pulsar MAXI J1816-195 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-21 Long Ji, Mingyu Ge, Yupeng Chen, Zhaosheng Li, Peng-Ju Wang, Shu Zhang and Shuang-Nan Zhang
We report accretion-powered pulsations for the first time during thermonuclear bursts in hard X-rays, which were observed with Insight-HXMT in 2022 during the outburst of the accreting X-ray millisecond pulsar MAXI J1816-195. By stacking 73 bursts, we detected pulse profiles in 8–30 and 30–100 keV during bursts, which are identical to those obtained from the persistent (nonburst) emission. On average
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Negative-energy Waves in the Vertical Threads of a Solar Prominence Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-18 Jincheng Wang, Dong Li, Chuan Li, Yijun Hou, Zhike Xue, Zhe Xu, Liheng Yang, Qiaoling Li
Solar prominences, intricate structures on the Sun’s limb, have been a subject of fascination owing to their threadlike features and dynamic behaviors. Utilizing data from the New Vacuum Solar Telescope, Chinese Hα Solar Explorer, and Solar Dynamics Observatory, this study investigates the transverse swaying motions observed in the vertical threads of a solar prominence during its eruption onset on
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Simulating X-Ray Reverberation in the Ultraviolet-emitting Regions of Active Galactic Nuclei Accretion Disks with Three-dimensional Multifrequency Radiation Magnetohydrodynamic Simulations Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-17 Amy Secunda, Yan-Fei Jiang, 燕飞 姜 and Jenny E. Greene
Active galactic nuclei (AGN) light curves observed with different wave bands show that the variability in longer wavelength bands lags the variability in shorter wavelength bands. Measuring these lags, or reverberation mapping, is used to measure the radial temperature profile and extent of AGN disks, typically with a reprocessing model that assumes X-rays are the main driver of the variability in
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A JWST Survey of the Supernova Remnant Cassiopeia A Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-16 Dan Milisavljevic, Tea Temim, Ilse De Looze, Danielle Dickinson, J. Martin Laming, Robert Fesen, John C. Raymond, Richard G. Arendt, Jacco Vink, Bettina Posselt, George G. Pavlov, Ori D. Fox, Ethan Pinarski, Bhagya Subrayan, Judy Schmidt, William P. Blair, Armin Rest, Daniel Patnaude, Bon-Chul Koo, Jeonghee Rho, Salvatore Orlando, Hans-Thomas Janka, Moira Andrews, Michael J. Barlow, Adam Burrows, Roger
We present initial results from a James Webb Space Telescope (JWST) survey of the youngest Galactic core-collapse supernova remnant, Cassiopeia A (Cas A), made up of NIRCam and MIRI imaging mosaics that map emission from the main shell, interior, and surrounding circumstellar/interstellar material (CSM/ISM). We also present four exploratory positions of MIRI Medium Resolution Spectrograph integral
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Discovery of Thionylimide, HNSO, in Space: The first N-, S-, and O-bearing Interstellar Molecule Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-16 Miguel Sanz-Novo, Víctor M. Rivilla, Holger S. P. Müller, Izaskun Jiménez-Serra, Jesús Martín-Pintado, Laura Colzi, Shaoshan Zeng, Andrés Megías, Álvaro López-Gallifa, Antonio Martínez-Henares, Belén Tercero, Pablo de Vicente, David San Andrés, Sergio Martín, Miguel A. Requena-Torres
We present the first detection in space of thionylimide (HNSO) toward the Galactic center molecular cloud G + 0.693-0.027, thanks to the superb sensitivity of an ultradeep molecular line survey carried out with the Yebes 40 m and IRAM 30 m telescopes. This molecule is the first species detected in the interstellar medium containing, simultaneously, N, S, and O. We have identified numerous K a = 0,
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Tidal Disruption Encores Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-16 Taeho Ryu, Rosalba Perna, Matteo Cantiello
Nuclear star clusters (NSCs), made up of a dense concentration of stars and the compact objects they leave behind, are ubiquitous in the central regions of galaxies surrounding the central supermassive black hole (SMBH). Close interactions between stars and stellar-mass black holes (sBHs) lead to tidal disruption events (TDEs). We uncover an interesting new phenomenon: for a subset of these, the unbound
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An X-Ray Census of Active Galactic Nuclei in the Virgo and Fornax Clusters of Galaxies with SRG/eROSITA Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-15 Meicun Hou, Zhensong Hu, Zhiyuan Li
We present a uniform and sensitive X-ray census of active galactic nuclei (AGNs) in the two nearest galaxy clusters, Virgo and Fornax, utilizing the newly released X-ray source catalogs from the first all-sky scan of Spectrum-Roentgen-Gamma/eROSITA. A total of 50 and 10 X-ray sources are found positionally coincident with the nuclei of member galaxies in Virgo and Fornax, respectively, down to a 0
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Rotational Spectrum and First Interstellar Detection of 2-methoxyethanol Using ALMA Observations of NGC 6334I Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-12 Zachary T. P. Fried, Samer J. El-Abd, Brian M. Hays, Gabi Wenzel, Alex N. Byrne, Laurent Margulès, Roman A. Motiyenko, Steven T. Shipman, Maria P. Horne, Jes K. Jørgensen, Crystal L. Brogan, Todd R. Hunter, Anthony J. Remijan, Andrew Lipnicky, Ryan A. Loomis, Brett A. McGuire
We use both chirped-pulse Fourier transform and frequency-modulated absorption spectroscopy to study the rotational spectrum of 2-methoxyethanol (CH3OCH2CH2OH) in several frequency regions ranging from 8.7 to 500 GHz. The resulting rotational parameters permitted a search for this molecule in Atacama Large Millimeter/submillimeter Array (ALMA) observations toward the massive protocluster NGC 6334I
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Axial Flux Evolution of Small-scale Magnetic Flux Ropes from 0.06 to 10 au Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-11 Hameedullah Farooki, Jeongwoo Lee, Francesco Pecora, Haimin Wang, Hyomin Kim
Small-scale magnetic flux ropes (SMFRs) fill much of the solar wind, but their origin and evolution are debated. We apply our recently developed, improved Grad–Shafranov algorithm for the detection and reconstruction of SMFRs to data from Parker Solar Probe, Solar Orbiter, Wind, and Voyager 1 and 2 to detect events from 0.06 to 10 au. We observe that the axial flux density is the same for SMFRs of
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A Candidate Supermassive Black Hole in a Gravitationally Lensed Galaxy at Z ≈ 10 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-11 Orsolya E. Kovács, Ákos Bogdán, Priyamvada Natarajan, Norbert Werner, Mojegan Azadi, Marta Volonteri, Grant R. Tremblay, Urmila Chadayammuri, William R. Forman, Christine Jones, Ralph P. Kraft
While supermassive black holes (SMBHs) are widely observed in the nearby and distant Universe, their origin remains debated with two viable formation scenarios with light and heavy seeds. In the light seeding model, the seed of the first SMBHs form from the collapse of massive stars with masses of 10–100 M ⊙, while the heavy seeding model posits the formation of 104–5 M ⊙ seeds from direct collapse
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NICER, NuSTAR, and Insight-HXMT Views to Black Hole X-Ray Binary SLX 1746–331 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-11 Jing-Qiang Peng, Shu Zhang, Qing-Cang Shui, Shuang-Nan Zhang, Yu-Peng Chen, Ling-Da Kong, Zhuo-Li Yu, Long Ji, Peng-Ju Wang, Ming-Yu Ge, Jin-Lu Qu, Lian Tao, Zhi Chang, Jian Li, Zhao-sheng Li, Zhe Yan
We study the spectral and temporal properties of the black hole (BH) X-ray transient binary SLX 1746–331 during the 2023 outburst with NICER, NuSTAR, and Insight-HXMT observations. Through the joint fitting of the spectra from NICER, NuSTAR, and Insight-HXMT, the spin and inclination angles are measured for the first time as 0.85 ± 0.03 and 53° ± 0.°5, respectively. Accordingly, the mass of the compact
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Ultradeep Cover: An Exotic and Jetted Tidal Disruption Event Candidate Disguised as a Gamma-Ray Burst Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-11 R. A. J. Eyles-Ferris, C. J. Nixon, E. R. Coughlin, P. T. O’Brien
Gamma-ray bursts (GRBs) are traditionally classified as either short GRBs with durations ≲2 s that are powered by compact object mergers or long GRBs with durations ≳2 s that are powered by the deaths of massive stars. Recent results, however, have challenged this dichotomy and suggest that there exists a population of merger-driven long bursts. One such example, GRB 191019A, has a t 90 ≈ 64 s, but
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Cold Dark Matter and Self-interacting Dark Matter Interpretations of the Strong Gravitational Lensing Object JWST-ER1 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-11 Demao Kong, Daneng Yang, Hai-Bo Yu
van Dokkum et al. reported the discovery of JWST-ER1, a strong lensing object at redshift z ≈ 2, using data from the James Webb Space Telescope. The lens mass within the Einstein ring is 5.9 times higher than the expected stellar mass from a Chabrier initial mass function, indicating a high dark matter density. In this work, we show that a cold dark matter halo, influenced by gas-driven adiabatic contraction
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Vortex Fiber Nulling for Exoplanet Observations: First Direct Detection of M Dwarf Companions around HIP 21543, HIP 94666, and HIP 50319 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-10 Daniel Echeverri, Jerry W. Xuan, John D. Monnier, Jacques-Robert Delorme, Jason J. Wang, Nemanja Jovanovic, Katelyn Horstman, Garreth Ruane, Bertrand Mennesson, Eugene Serabyn, Dimitri Mawet, J. Kent Wallace, Sofia Hillman, Ashley Baker, Randall Bartos, Benjamin Calvin, Sylvain Cetre, Greg Doppmann, Luke Finnerty, Michael P. Fitzgerald, Chih-Chun Hsu, Joshua Liberman, Ronald López, Maxwell Millar-Blanchaer
Vortex fiber nulling (VFN) is a technique for detecting and characterizing faint companions at small separations from their host star. A near-infrared (∼2.3 μm) VFN demonstrator mode was deployed on the Keck Planet Imager and Characterizer (KPIC) instrument at the Keck Observatory and presented earlier. In this Letter, we present the first VFN companion detections. Three targets, HIP 21543 Ab, HIP
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Discovery of the Longest-period Classical Cepheid in the Milky Way Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-10 I. Soszyński, D. M. Skowron, A. Udalski, P. Pietrukowicz, M. Gromadzki, M. K. Szymański, J. Skowron, P. Mróz, R. Poleski, S. Kozłowski, P. Iwanek, M. Wrona, K. Ulaczyk, K. Rybicki, M. Mróz
We report the discovery of the classical Cepheid OGLE-GD-CEP-1884 (= GDS_J1535467-555656) with the longest pulsation period known in our Galaxy. The period of 78.14 days is nearly 10 days longer than that of the previous record-holding Cepheid, S Vulpeculae, and thus, OGLE-GD-CEP-1884 can be categorized as the first ultra-long-period Cepheid in the Milky Way. This star is present in the ASAS-SN and
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Comprehensive Analysis of a Filament-embedding Solar Active Region at Different Stages of Evolution Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-10 Jie Zhao, Fu Yu, Sarah E. Gibson, Yuhong Fan, Yang Su, Ying Li, Jun Dai, Hui Li, Chuan Li, Pengfei Chen, Ming-De Ding, Cheng Fang
Active regions are the brightest structures seen in the solar corona, so their physical properties hold important clues to the physical mechanisms underlying coronal heating. In this work, we present a comprehensive study for a filament-embedding active region as determined from observations from multiple facilities including the Chinese Hα Solar Explorer. We find three types of dynamic features that
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tdescore: An Accurate Photometric Classifier for Tidal Disruption Events Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-10 Robert Stein, Ashish Mahabal, Simeon Reusch, Matthew Graham, Mansi M. Kasliwal, Marek Kowalski, Suvi Gezari, Erica Hammerstein, Szymon J. Nakoneczny, Matt Nicholl, Jesper Sollerman, Sjoert van Velzen, Yuhan Yao, Russ R. Laher, Ben Rusholme
Optical surveys have become increasingly adept at identifying candidate tidal disruption events (TDEs) in large numbers, but classifying these generally requires extensive spectroscopic resources. Here we present tdescore, a simple binary photometric classifier that is trained using a systematic census of ∼3000 nuclear transients from the Zwicky Transient Facility (ZTF). The sample is highly imbalanced
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Model-independent Way to Determine the Hubble Constant and the Curvature from the Phase Shift of Gravitational Waves with DECIGO Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-09 Tonghua Liu, Shuo Cao, Marek Biesiada, Yilong Zhang, Jieci Wang
In this Letter, we propose a model-independent method to determine the Hubble constant and curvature simultaneously by taking advantage of the possibilities of future spaceborne gravitational-wave detector DECIGO in combination with the radio quasars as standard rulers. Similarly to the redshift drift in the electromagnetic domain, accelerating expansion of the Universe causes a characteristic phase
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Drivers of Magnetic Field Amplification at Oblique Shocks: In Situ Observations Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-09 Hadi Madanian, Imogen Gingell, Li-Jen Chen, Eli Monyek
Collisionless shocks are ubiquitous structures throughout the Universe. Shock waves in space and astrophysical plasmas convert the energy of a fast-flowing plasma to other forms of energy, including thermal and magnetic energies. Plasma turbulence and high-amplitude electric and magnetic fluctuations are necessary for effective energy conversion and particle acceleration. We survey and characterize
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JWST MIRI MRS Images of Disk Winds, Water, and CO in an Edge-on Protoplanetary Disk Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-09 Nicole Arulanantham, M. K. McClure, Klaus Pontoppidan, Tracy L. Beck, J. A. Sturm, D. Harsono, A. C. A. Boogert, M. Cordiner, E. Dartois, M. N. Drozdovskaya, C. Espaillat, G. J. Melnick, J. A. Noble, M. E. Palumbo, Y. J. Pendleton, H. Terada, E. F. van Dishoeck
We present JWST MIRI MRS observations of the edge-on protoplanetary disk around the young subsolar-mass star Tau 042021, acquired as part of the Cycle 1 GO program “Mapping Inclined Disk Astrochemical Signatures.” These data resolve the mid-IR spatial distributions of H2, revealing X-shaped emission extending to ∼200 au above the disk midplane with a semiopening angle of 35° ± 5°. We do not velocity-resolve
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The Next Generation Deep Extragalactic Exploratory Public (NGDEEP) Survey Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-09 Micaela B. Bagley, Nor Pirzkal, Steven L. Finkelstein, Casey Papovich, Danielle A. Berg, Jennifer M. Lotz, Gene C. K. Leung, Henry C. Ferguson, Anton M. Koekemoer, Mark Dickinson, Jeyhan S. Kartaltepe, Dale D. Kocevski, Rachel S. Somerville, L. Y. Aaron Yung, Bren E. Backhaus, Caitlin M. Casey, Marco Castellano, Óscar A. Chávez Ortiz, Katherine Chworowsky, Isabella G. Cox, Romeel Davé, Kelcey Davis
We present the Next Generation Deep Extragalactic Exploratory Public (NGDEEP) Survey, a deep slitless spectroscopic and imaging Cycle 1 JWST treasury survey designed to constrain feedback mechanisms in low-mass galaxies across cosmic time. NGDEEP targets the Hubble Ultra Deep Field (HUDF) with NIRISS slitless spectroscopy ( flim,line,5σ≈1.2× 10−18 erg s−1 cm−2) to measure metallicities and star formation
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Discovery of Merging Twin Quasars at z = 6.05 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-05 Yoshiki Matsuoka, Takuma Izumi, Masafusa Onoue, Michael A. Strauss, Kazushi Iwasawa, Nobunari Kashikawa, Masayuki Akiyama, Kentaro Aoki, Junya Arita, Masatoshi Imanishi, Rikako Ishimoto, Toshihiro Kawaguchi, Kotaro Kohno, Chien-Hsiu Lee, Tohru Nagao, John D. Silverman, Yoshiki Toba
We report the discovery of two quasars at a redshift of z = 6.05 in the process of merging. They were serendipitously discovered from the deep multiband imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program survey. The quasars, HSC J121503.42−014858.7 (C1) and HSC J121503.55−014859.3 (C2), both have luminous (>1043 erg s−1) Lyα emission with a clear broad component (full width
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A Unifying Model of Mixed Inertial Modes in the Sun Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-05 Rekha Jain, Bradley W. Hindman, Catherine Blume
We present an analytical model that unifies many of the inertial waves that have been recently observed on the surface of the Sun, as well as many other modes that have been theoretically predicted—but have yet to be observed—into a single family of mixed inertial modes. By mixed, we mean that the prograde- and retrograde-propagating members of this family have different restoring forces and hence
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On the Chemical and Kinematic Signatures of the Resonances of the Galactic Bar as Revealed by the LAMOST-APOGEE Red Clump Stars Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-05 Weixiang Sun, Han Shen, Biwei Jiang, Xiaowei Liu
The Milky Way is widely considered to exhibit features of a rotational bar or quadrupole bar. In either case, the feature of the resonance of the Galactic bar should be present in the properties of the chemistry and kinematics, over a large area of the disk. With a sample of over 170,000 red clump stars from LAMOST-APOGEE data, we attempt to detect the chemical and kinematic signatures of the resonances
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Recovery of High-energy Low-frequency Quasiperiodic Oscillations from Black Hole X-Ray Binary MAXI J1535–571 with a Hilbert–Huang Transform Method Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-05 Qing C. Shui, S. Zhang, Shuang N. Zhang, Yu P. Chen, Ling D. Kong, Jing Q. Peng, L. Ji, Peng J. Wang, Z. Chang, Zhuo L. Yu, Hong X. Yin, Jin L. Qu, L. Tao, Ming Y. Ge, X. Ma, L. Zhang, W. Yu, J. Li
We propose a method based on the Hilbert–Huang transform (HHT) to recover the high-energy waveform of low-frequency quasiperiodic oscillations (QPOs). Based on the method, we successfully obtain the modulation of the phase-folded light curve above 170 keV using the QPO phase reconstructed at lower energies in MAXI J1535–571 with Insight-HXMT observations. A comprehensive simulation study is conducted
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Discovery of a Rare Eclipsing Be/X-Ray Binary System, Swift J010902.6-723710 = SXP 182 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-05 Thomas M. Gaudin, Jamie A. Kennea, M. J. Coe, I. M. Monageng, Andrzej Udalski, L. J. Townsend, David A. H. Buckley, Phil A. Evans
We report on the discovery of Swift J010902.6-723710, a rare eclipsing Be/X-ray Binary system by the Swift SMC Survey (S-CUBED). Swift J010902.6-723710 was discovered via weekly S-CUBED monitoring observations when it was observed to enter a state of X-ray outburst on 2023 October 10. X-ray emission was found to be modulated by a 182 s period. Optical spectroscopy is used to confirm the presence of
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New Light on Dark Extended Lenses with the Roman Space Telescope Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-04 William DeRocco, Nolan Smyth, Volodymyr Takhistov
The Roman Space Telescope’s Galactic Bulge Time Domain Survey will constitute the most sensitive microlensing survey of the Galactic bulge to date, opening up new opportunities to search for dark matter (DM). Many extensions of the Standard Model predict the formation of extended DM substructures, such as DM subhalos, boson/axion stars, and halo-dressed primordial black holes. We demonstrate that for
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3D Magnetic Free Energy and Flaring Activity Using 83 Major Solar Flares Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-04 Khojiakbar Karimov, Harim Lee, Hyun-Jin Jeong, Yong-Jae Moon, Jihye Kang, Jihyeon Son, Mingyu Jeon, Kanya Kusano
In this Letter, we examine the relationship between 3D magnetic free energy (MFE) and flaring activity using 83 major solar flares (M-class and X-class) in nine solar active regions (ARs). For this, we use 998 nonlinear force-free field extrapolations compiled by the “Institute for Space-Earth Environmental Research Database” at Nagoya University. These ARs produced at least three major flares with
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The Awakening of a Blazar at Redshift 2.7 Temporally Coincident with the Arrival of Cospatial Neutrino Event IceCube-201221A Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-04 Xiong Jiang, Neng-Hui Liao, Yi-Bo Wang, Rui Xue, Ning Jiang, Ting-Gui Wang
We report on multiwavelength studies of a blazar NVSS J171822+423948, which is identified as the low-energy counterpart of 4FGL J1718.5+4237, the unique γ-ray source known to be cospatial with the IceCube neutrino event IC-201221A. After a 12 yr long quiescent period undetected by Fermi-LAT, γ-ray activities with a tenfold flux increase emerge soon (a few tens of days) after the arrival of the neutrino
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Adjusting the Potential Field Source Surface Height Based on Magnetohydrodynamic Simulations Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-04-03 Zhenguang Huang, Gábor Tóth, Jia Huang, Nishtha Sachdeva, Bart van der Holst, Ward B. Manchester
A potential field solution is widely used to extrapolate the coronal magnetic field above the Sun’s surface to a certain height. This model applies the current-free approximation and assumes that the magnetic field is entirely radial beyond the source surface height, which is defined as the radial distance from the center of the Sun. Even though the source surface is commonly specified at 2.5 R s (solar
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Quiet-time Spectra of Suprathermal Heavy Ions near 1 au in Solar Cycles 23 and 24 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-28 B. L. Alterman, Mihir I. Desai, Maher A. Dayeh, Glenn M. Mason, George C. Ho
We report on the annual variation of quiet-time suprathermal heavy ion spectral indices for C through Fe in the energy range 0.3–1.28 MeV nuc−1 during Solar Cycle 23's rising phase through Solar Cycle 24's declining phase. These Advanced Composition Explorer/Ultra-Low Energy Isotope Spectrometer measurements cover 1998–2019. We show that the average quiet-time suprathermal spectral index across species
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JWST NIRCam Photometry: A Study of Globular Clusters Surrounding Bright Elliptical Galaxy VV 191a at z = 0.0513 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-28 Jessica M. Berkheimer, Timothy Carleton, Rogier A. Windhorst, William C. Keel, Benne W. Holwerda, Mario Nonino, Seth H. Cohen, Rolf A. Jansen, Dan Coe, Christopher J. Conselice, Simon P. Driver, Brenda L. Frye, Norman A. Grogin, Anton M. Koekemoer, Ray A. Lucas, Madeline A. Marshall, Nor Pirzkal, Clayton Robertson, Aaron Robotham, Russell E. Ryan, Brent M. Smith, Jake Summers, Scott Tompkins, Christopher
James Webb Space Telescope NIRCam images have revealed 154 reliable globular cluster (GC) candidates around the z = 0.0513 elliptical galaxy VV 191a after subtracting 34 likely interlopers from background galaxies inside our search area. NIRCam broadband observations are made at 0.9–4.5 μm using the F090W, F150W, F356W, and F444W filters. Using point-spread-function-matched photometry, the data are
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Insights into Galaxy Morphology and Star Formation: Unveiling Filamentary Structures around an Extreme Overdensity at z ∼ 1.5 Traced by [O ii] Emitters Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-28 Ronaldo Laishram, Tadayuki Kodama, Takahiro Morishita, Andreas Faisst, Yusei Koyama, Naoaki Yamamoto
We explore the morphological features and star formation activities of [O ii] emitters in the COSMOS UltraDeep field at z ∼ 1.5 using JWST NIRCam data from the COSMOS-Web survey and Subaru Hyper Suprime-Cam. We also report the discovery of large filamentary structures traced by [O ii] emitters surrounding an extremely overdense core with a galaxy number density ∼11× higher than the field average. These
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The Bright Rim Prominences according to 2.5D Radiative Transfer Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-28 Jack M. Jenkins, Christopher M. J. Osborne, Ye Qiu, Rony Keppens, Chuan Li
Solar prominences observed close to the limb commonly include a bright feature that, from the perspective of the observer, runs along the interface between itself and the underlying chromosphere. Despite several idealized models being proposed to explain the underlying physics, a more general approach remains outstanding. In this manuscript we demonstrate as a proof of concept the first steps in applying
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A Full Resolution of the 450 μm Extragalactic Background Light Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-28 Qi-Ning Hsu, L. L. Cowie, Chian-Chou Chen, A. J. Barger
The extragalactic background light (EBL) is the cumulative radiation outside the Milky Way. The determination of its corresponding primary emitting sources as well as its total energy level across the entire electromagnetic spectrum has profound implications for both cosmology and galaxy formation. However, the detailed origin of the EBL at far-infrared wavelengths, particularly those close to the
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Reevaluating the Origin of Detectable Cataclysmic Variables in Globular Clusters: Testing the Importance of Dynamics Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 Liliana Rivera Sandoval, Diogo Belloni, Miriam Ramos Arevalo
Based on the current detectable cataclysmic variable (CV) population in Galactic globular clusters (GCs), we show that there is not a clear relation between the number of sources per unit of mass and the stellar encounter rate, the cluster mass, or the cluster central density. If any, only in the case of core-collapsed GCs could there be an anticorrelation with the stellar encounter rate. Our findings
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Analytic Model and Magnetohydrodynamic Simulations of Three-dimensional Magnetic Switchbacks Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 Chen Shi, Marco Velli, Gabor Toth, Kun Zhang, Anna Tenerani, Zesen Huang, Nikos Sioulas, Bart van der Holst
Parker Solar Probe observations reveal that the near-Sun space is almost filled with magnetic switchbacks (“switchbacks” hereinafter), which may be a major contributor to the heating and acceleration of solar wind. Here, for the first time, we develop an analytic model of an axisymmetric switchback with uniform magnetic field strength. In this model, three parameters control the geometry of the switchback:
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First Sagittarius A* Event Horizon Telescope Results. VII. Polarization of the Ring Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 The Event Horizon Telescope Collaboration, Kazunori Akiyama, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Uwe Bach, Anne-Kathrin Baczko, David Ball, Mislav Balokovic, Bidisha Bandyopadhyay, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer
The Event Horizon Telescope observed the horizon-scale synchrotron emission region around the Galactic center supermassive black hole, Sagittarius A* (Sgr A*), in 2017. These observations revealed a bright, thick ring morphology with a diameter of 51.8 ± 2.3 μas and modest azimuthal brightness asymmetry, consistent with the expected appearance of a black hole with mass M ≈ 4 × 106 M ⊙. From these observations
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First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 The Event Horizon Telescope Collaboration, Kazunori Akiyama, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Uwe Bach, Anne-Kathrin Baczko, David Ball, Mislav Baloković, Bidisha Bandyopadhyay, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer
In a companion paper, we present the first spatially resolved polarized image of Sagittarius A* on event horizon scales, captured using the Event Horizon Telescope, a global very long baseline interferometric array operating at a wavelength of 1.3 mm. Here we interpret this image using both simple analytic models and numerical general relativistic magnetohydrodynamic (GRMHD) simulations. The large
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Electrostatic Wave Decay in the Randomly Inhomogeneous Solar Wind Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 C. Krafft, P. Savoini
Despite a few space observations where Langmuir and ion acoustic waves are expected to participate in the mechanism of electrostatic decay, this is to date believed to be the main and fastest nonlinear wave process in the solar wind. However, in such a plasma where random density fluctuations are ubiquitous, the question of whether nonlinear wave processes play a significant role in Langmuir wave turbulence
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A Bias-corrected Luminosity Function for Red Supergiant Supernova Progenitor Stars Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-27 Nora L. Strotjohann, Eran O. Ofek, Avishay Gal-Yam
The apparent tension between the luminosity functions of red supergiant (RSG) stars and of RSG progenitors of Type II supernovae (SNe) is often referred to as the RSG problem and it motivated some to suggest that many RSGs end their life without an SN explosion. However, the luminosity functions of RSG SN progenitors presented so far were biased to high luminosities, because the sensitivity of the
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AT 2023lli: A Tidal Disruption Event with Prominent Optical Early Bump and Delayed Episodic X-Ray Emission Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-26 Shifeng Huang, Ning Jiang, Jiazheng Zhu, Yibo Wang, Tinggui Wang, Shan-Qin Wang, Wen-Pei Gan, En-Wei Liang, Yu-Jing Qin, Zheyu Lin, Lin-Na Xu, Min-Xuan Cai, Ji-an Jiang, Xu Kong, Jiaxun Li, Long li, Jian-Guo Wang, Ze-Lin Xu, Yongquan Xue, Ye-Fei Yuan, Jingquan Cheng, Lulu Fan, Jie Gao, Lei Hu, Weida Hu, Bin Li, Feng Li, Ming Liang, Hao Liu, Wei Liu, Zheng Lou, Wentao Luo, Yuan Qian, Jinlong Tang, Zhen
High-cadence, multiwavelength observations have continuously revealed the diversity of tidal disruption events (TDEs), thus greatly advancing our knowledge and understanding of TDEs. In this work, we conducted an intensive optical-UV and X-ray follow-up campaign of TDE AT 2023lli and found a remarkable month-long bump in its UV/optical light curve nearly 2 months prior to maximum brightness. The bump
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Rest-frame UV Colors for Faint Galaxies at z ∼ 9–16 with the JWST NGDEEP Survey Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-26 Alexa M. Morales, Steven L. Finkelstein, Gene C. K. Leung, Micaela B. Bagley, Nikko J. Cleri, Romeel Dave, Mark Dickinson, Henry C. Ferguson, Nimish P. Hathi, Ewan Jones, Anton M. Koekemoer, Casey Papovich, Pablo G. Pérez-González, Nor Pirzkal, Britton Smith, Stephen M. Wilkins, L. Y. Aaron Yung
We present measurements of the rest-frame UV spectral slope, β, for a sample of 36 faint star-forming galaxies at z ∼ 9–16 discovered in one of the deepest JWST NIRCam surveys to date, the Next Generation Deep Extragalactic Exploratory Public Survey. We use robust photometric measurements for UV-faint galaxies (down to M UV ∼ −16), originally published in Leung et al., and measure values of the UV
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On the Maximum Black Hole Mass at Solar Metallicity Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-26 Amedeo Romagnolo, Alex C. Gormaz-Matamala, Krzysztof Belczynski
In high-metallicity environments the mass that black holes (BHs) can reach just after core collapse widely depends on how much mass their progenitor stars lose via winds. On one hand, new theoretical and observational insights suggest that early-stage winds should be weaker than what many canonical models prescribe. On the other hand, the proximity to the Eddington limit should affect the formation
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Electron and Proton Energization in 3D Reconnecting Current Sheets in Semirelativistic Plasma with Guide Magnetic Field Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-22 Gregory R. Werner, Dmitri A. Uzdensky
Using 3D particle-in-cell simulation, we characterize energy conversion, as a function of guide magnetic field, in a thin current sheet in semirelativistic plasma, with relativistic electrons and subrelativistic protons. There, magnetic reconnection, the drift-kink instability (DKI), and the flux-rope kink instability all compete and interact in their nonlinear stages to convert magnetic energy to
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Excited-state OH Masers in the Water Fountain Source IRAS 18460-0151 Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-20 Xu-Jia Ouyang, Yong Zhang, Juan Li, Jun-ichi Nakashima, Xi Chen, Hai-Hua Qiao
Water fountain objects are generally defined as evolved stars with low to intermediate initial mass accompanied by high-velocity molecular jets detectable in the 22.235 GHz H2O maser line. They are the key objects of understanding the morphological transitions of circumstellar envelopes during the post asymptotic giant branch phase. Masers are useful tools to trace the kinematic environments of the
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The Geochemical Potential for Metabolic Processes on the Sub-Neptune Exoplanet K2-18b Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-20 Christopher R. Glein
Quantifying disequilibria is important to understand whether an environment could be habitable. It has been proposed that the exoplanet K2-18b has a hydrogen-rich atmosphere and a water ocean, making it a “hycean world.” The James Webb Space Telescope recently made measurements of methane, CO2, and possibly dimethyl sulfide (DMS) in the atmosphere of this planet. The initial interpretation of these
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Physical Correlations and Predictions Emerging from Modern Core-collapse Supernova Theory Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-19 Adam Burrows, Tianshu Wang, David Vartanyan
In this paper, we derive correlations between core-collapse supernova observables and progenitor core structures that emerge from our suite of 20 state-of-the-art 3D core-collapse supernova simulations carried to late times. This is the largest such collection of 3D supernova models ever generated and allows one to witness and derive testable patterns that might otherwise be obscured when studying
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A Short Intense Dynamo at the Onset of Crystallization in White Dwarfs Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-19 J. R. Fuentes, Matias Castro-Tapia, Andrew Cumming
The origin of large magnetic fields (≳106 G) in isolated white dwarfs is not clear. One possible explanation is that crystallization of the star’s core drives compositional convection, which when combined with the star’s rotation, can drive a dynamo. However, whether convection is efficient enough to explain the large intensity of the observed magnetic fields is still under debate. Recent work has
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The Effect of Fast Solar Wind on Ion Distribution Downstream of Earth’s Bow Shock Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-18 Florian Koller, Savvas Raptis, Manuela Temmer, Tomas Karlsson
The solar wind gets thermalized and compressed when crossing a planetary bow shock, forming the magnetosheath. The angle between the upstream magnetic field and the shock normal vector separates the quasi-parallel from the quasi-perpendicular magnetosheath, significantly influencing the physical conditions in these regions. A reliable classification between both magnetosheath regions is of utmost importance
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The NANOGrav 15 yr Data Set: Search for Transverse Polarization Modes in the Gravitational-wave Background Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-18 Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Dallas DeGan
Recently we found compelling evidence for a gravitational-wave background with Hellings and Downs (HD) correlations in our 15 yr data set. These correlations describe gravitational waves as predicted by general relativity, which has two transverse polarization modes. However, more general metric theories of gravity can have additional polarization modes, which produce different interpulsar correlations
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Predicting the Dominant Formation Mechanism of Multiplanetary Systems Astrophys. J. Lett. (IF 7.9) Pub Date : 2024-03-15 Cheyanne Shariat, Yasuhiro Hasegawa, Bradley M. S. Hansen, Tze Yeung Mathew Yu, Renyu Hu
Most, if not all, Sun-like stars host one or more planets, making multiplanetary systems commonplace in our Galaxy. We utilize hundreds of multiplanet simulations to explore the origin of such systems, focusing on their orbital architecture. The first set of simulations assumes in situ assembly of planetary embryos, while the second explores planetary migration. After applying observational biases