The Astrophysical Journal最新文献

{"title":"Height-dependent Slow Magnetoacoustic Wave Amplitude and Energy Flux in Sunspot Atmospheres","authors":"Y. Sanjay, S. Krishna Prasad and P. S. Rawat","doi":"10.3847/1538-4357/add336","DOIUrl":"https://doi.org/10.3847/1538-4357/add336","url":null,"abstract":"Slow magnetoacoustic waves (SMAWs) have been considered a possible candidate for chromospheric heating in the past. This study analyzed 20 active regions observed between 2012 and 2016 to examine the amplitude and energy flux variation of SMAWs in the umbral atmosphere. Six different wavelength channels from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, covering regions from the photosphere to the low corona, were utilized for this purpose. The wave amplitude estimations show a gradual increase in 3 minute oscillation amplitude, peaking between 700 and 900 km, followed by a steady decrease; further, at altitudes greater than 1800 km, it appears to increase and decrease again. The corresponding energy flux, on the other hand, displays a steady and monotonous decrease with a significant reduction in value from approximately 3.32 ± 0.50 kW m−2 near the photosphere to about 6.47 ± 3.16 ×10−4 W m−2 at an altitude of 2585 km. This decay may be attributed to radiative damping and shock dissipation in the lower altitudes and thermal conduction and viscosity in the higher altitudes. The missing flux is a factor of 3–15 lower than that required to counterbalance the chromospheric radiative losses.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Density Profiles of TNG 300 Voids across Cosmic Time","authors":"Olivia Curtis, Bryanne McDonough and Tereasa G. Brainerd","doi":"10.3847/1538-4357/adcebf","DOIUrl":"https://doi.org/10.3847/1538-4357/adcebf","url":null,"abstract":"We present radial density profiles, as traced by luminous galaxies and dark matter particles, for voids in 11 snapshots of the TNG 300 simulation. The snapshots span 11.65 Gyr of cosmic time, corresponding to the redshift range 0 ≤ z ≤ 3. Using the comoving galaxy fields, voids were identified via a well-tested, watershed transformation-based algorithm. Voids were defined to be underdense regions that are unlikely to have arisen from Poisson noise, resulting in the selection of ∼100–200 of the largest underdense regions in each snapshot. At all redshifts, the radial density profiles as traced by both the galaxies and the dark matter resemble inverse top-hat functions. However, details of the functions (particularly the underdensities of the innermost regions and the overdensities of the ridges) evolve considerably more for the dark matter density profiles than for the galaxy density profiles. At all redshifts, a linear relationship between the galaxy and dark matter density profiles exists, and the slope of the relationship is similar to the bias estimates for TNG 300 snapshots. Lastly, we identify distinct environments in which voids can exist, defining “void-in-void” and “void-in-cloud” populations (i.e., voids that reside in larger underdense or overdense regions, respectively), and we investigate ways in which the relative densities of dark matter and galaxies in the interiors and ridges of these structures vary as a function of void environment.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional Orbit and Dynamical Masses of GJ 105 AC","authors":"Cayla M. Dedrick, Jason T. Wright, Jason D. Eastman, Cullen H. Blake, Samson A. Johnson, Peter Plavchan, John Asher Johnson, David H. Sliski, Maurice L. Wilson, Robert A. Wittenmyer, Thomas Barclay, Jonathan Horner, Stephen R. Kane and Sharon X. Wang","doi":"10.3847/1538-4357/adc564","DOIUrl":"https://doi.org/10.3847/1538-4357/adc564","url":null,"abstract":"The precision of stellar models is higher than the precision at which we are able to measure the masses of most stars, with the notable exception of binaries where we can determine dynamical masses of the component stars. In addition to well-measured stellar properties, the ideal benchmark star is far enough from its companion that its properties are indistinguishable from an otherwise identical single star. Currently, there are a handful of stars with precise (±3%), model-independent mass measurements that are “effectively single” and for which we can obtain clean spectra (i.e., spectra that are not blended with a close companion). In this paper, we introduce GJ 105 AC as the newest members of this exclusive population. We present an updated orbital analysis for the long-period K3+M7 binary GJ 105 AC. We jointly analyze radial velocity (RV) and relative astrometry data, including new RVs from the Miniature Exoplanet Radial Velocity Array that capture the full periapsis passage and the RV minimum of the 76.0 ± 1.3 yr orbit for the first time. We derive precise dynamical masses of M1 = 0.78 ± 0.02 M⊙ and M2 = 0.098 ± 0.002 M⊙. We find that of all stars with similarly precise masses (∼2%), GJ 105 AC stands out as having the widest on-sky separation after α Centauri AB, making it one of the most easily accessible to spectroscopy, as well as the the second-widest true separation, ensuring that its members are truly “effectively single” in terms of their evolution.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"134 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"JWST/MIRI Observations of Newly Formed Dust in the Cold, Dense Shell of the Type IIn SN 2005ip","authors":"Melissa Shahbandeh, Ori D. Fox, Tea Temim, Eli Dwek, Arkaprabha Sarangi, Nathan Smith, Luc Dessart, Bryony Nickson, Michael Engesser, Alexei V. Filippenko, Thomas G. Brink, WeiKang Zheng, Tamás Szalai, Joel Johansson, Armin Rest, Schuyler D. Van Dyk, Jennifer Andrews, Chris Ashall, Geoffrey C. Clayton, Ilse De Looze, James M. DerKacy, Michael Dulude, Ryan J. Foley, Suvi Gezari, Sebastian Gomez, Shireen Gonzaga, Siva Indukuri, Jacob Jencson, Mansi Kasliwal, Zachary G. Lane, Ryan Lau, David Law, Anthony Marston, Dan Milisavljevic, Richard O’Steen, Justin Pierel, Matthew Siebert, Michael Skrutskie, Lou Strolger, Samaporn Tinyanont, Qinan Wang, Brian Williams, Lin Xiao, Yi Yang and Szanna Zsíros","doi":"10.3847/1538-4357/adce77","DOIUrl":"https://doi.org/10.3847/1538-4357/adce77","url":null,"abstract":"Dust from core-collapse supernovae (CCSNe), specifically Type IIP supernovae (SNe IIP), has been suggested to be a significant source of the dust observed in high-redshift galaxies. CCSNe eject large amounts of newly formed heavy elements, which can condense into dust grains in the cooling ejecta. However, infrared (IR) observations of typical CCSNe generally measure dust masses that are too small to account for the dust production needed at high redshifts. Type IIn SNe (SNe IIn), classified by their dense circumstellar medium, are also known to exhibit strong IR emission from warm dust, but the dust origin and heating mechanism have generally remained unconstrained because of limited observational capabilities in the mid-IR (MIR). Here, we present a JWST/MIRI Medium Resolution Spectrograph spectrum of the SN IIn SN 2005ip nearly 17 yr post-explosion. The SN IIn SN 2005ip is one of the longest-lasting and most well-studied SNe observed to date. Combined with a Spitzer MIR spectrum of SN 2005ip obtained in 2008, this data set provides a rare 15 yr baseline, allowing for a unique investigation of the evolution of dust. The JWST spectrum shows the emergence of an optically thin silicate dust component (≳0.08 M⊙) that is either not present or more compact/optically thick in the earlier Spitzer spectrum. Our analysis shows that this dust is likely newly formed in the cold, dense shell (CDS), between the forward and reverse shocks, and was not preexisting at the time of the explosion. There is also a smaller mass of carbonaceous dust (≳0.005 M⊙) in the ejecta. These observations provide new insights into the role of SN dust production, particularly within the CDS, and its potential contribution to the rapid dust enrichment of the early Universe.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"98 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Searching for Compact Obscured Nuclei in Compton-thick Active Galactic Nuclei","authors":"Makoto A. Johnstone, George C. Privon, Loreto Barcos-Muñoz, A.S. Evans, S. Aalto, Lee Armus, Franz E. Bauer, L. Blecha, J. S. Gallagher, S. König, Claudio Ricci, Ezequiel Treister, Cosima Eibensteiner, Kimberly L. Emig, Kara N. Green, Devaky Kunneriath, Jaya Nagarajan-Swenson, Alejandro Saravia and Ilsang Yoon","doi":"10.3847/1538-4357/adcecb","DOIUrl":"https://doi.org/10.3847/1538-4357/adcecb","url":null,"abstract":"Compact obscured nuclei (CONs) are heavily obscured infrared cores that have been found in local (ultra-)luminous infrared galaxies. They show bright emission from vibrationally excited rotational transitions of HCN, known as HCN-vib, and are thought to harbor Compton-thick (CT, NH ≥ 1024 cm−2) active galactic nuclei (AGNs) or extreme compact starbursts. We explore the potential evolutionary link between CONs and CT-AGNs by searching for CONs in hard-X-ray-confirmed CT-AGNs from the Great Observatories All-sky LIRG Survey (GOALS). Here, we present new Atacama Large Millimeter/submillimeter Array Band 6 observations that targeted HCN-vib emission in four hard-X-ray-confirmed CT-AGNs. We analyze these objects together with literature HCN-vib measurements of five additional hard-X-ray-confirmed CT-AGNs from the GOALS sample. We do not detect any CONs in this combined sample of nine CT-AGNs. We then explore a proposed evolutionary sequence in which CONs evolve into X-ray-detectable CT-AGNs once outflows and feedback reduce the column densities of the enshrouding gas. We find, however, no evidence of well-developed dense molecular outflows in the observed CT-AGNs. While this could suggest that CT-AGNs are not universally linked to CONs, it could also be explained by a short duty cycle for molecular outflows.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Fast X-Ray Variability around an Accreting Black Hole","authors":"Yejing Zhan, Bei You, Adam Ingram, Wenkang Jiang and Fayin Wang","doi":"10.3847/1538-4357/adcf1d","DOIUrl":"https://doi.org/10.3847/1538-4357/adcf1d","url":null,"abstract":"X-ray interband time lags are observed during the outbursts of black hole X-ray binaries. Timing analysis of fast variability in low Fourier frequency bands shows that high-energy photons lag behind low-energy photons, a phenomenon referred to as hard lag. Conversely, in high Fourier frequency bands, low-energy photons lag behind high-energy photons, known as soft lag. This frequency-dependent lag spectrum suggests that the lags arise from different physical processes. Notably, a trend has been observed wherein the lags shift toward shorter timescales during the rising hard state, indicating an evolution in the inner accretion flow. In this study, we simulate these interband lags by conducting Monte Carlo simulations of the rapid variability within the geometry of a jet base corona. We consider both inward propagating accretion rate fluctuations and reverberation (light-crossing) delays in our simulations. We successfully reproduce both low-frequency hard lags and high-frequency soft lags in a self-consistent manner. We replicate the observed evolution of the frequency-dependent lag spectra by varying the geometrical scale of the corona and the viscous frequency of the disk. Finally, we discuss the potential of a spherical corona and emphasize that polarization observations from the Imaging X-ray Polarimetry Explorer and the enhanced X-ray Timing and Polarimetry mission will be crucial for distinguishing the corona’s geometry in future studies.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evidence of Minijet Emission in a Large Emission Zone from a Magnetically Dominated Gamma-Ray Burst Jet","authors":"S.-X. Yi, C.-W. Wang, X. Shao, R. Moradi, H. Gao, B. Zhang, S.-L. Xiong, S.-N. Zhang, W.-J. Tan, J.-C. Liu, W.-C. Xue, Y.-Q. Zhang, C. Zheng, Y. Wang, P. Zhang, Z.-H. An, C. Cai, P.-Y. Feng, K. Gong, D.-Y. Guo, Y. Huang, B. Li, X.-B. Li, X.-Q. Li, X.-J. Liu, Y.-Q. Liu, X. Ma, W.-X. Peng, R. Qiao, L.-M. Song, J. Wang, P. Wang, Y. Wang, X.-Y. Wen, S. Xiao, Y.-B. Xu, S. Yang, Q.-B. Yi, D.-L. Zhang, F. Zhang, H.-M. Zhang, J.-P. Zhang, Z. Zhang, X.-Y. Zhao, Y. Zhao and S.-J. Zheng","doi":"10.3847/1538-4357/adcf98","DOIUrl":"https://doi.org/10.3847/1538-4357/adcf98","url":null,"abstract":"The second brightest gamma-ray burst (GRB) in history, GRB 230307A, provides an ideal laboratory to study the mechanism of GRB prompt emission thanks to its extraordinarily high photon statistics and its single-episode activity. Here we demonstrate that the rapidly variable components of its prompt emission compose an overall broad single pulse-like profile. Although these individual rapid components are aligned in time across all energy bands, this overall profile conspires to show a well-defined energy-dependent behavior that is typically seen in single GRB pulses. Such a feature demonstrates that the prompt emission of this burst is from many individual emitting units that are casually linked in a emission site at a large distance from the central engine. Such a scenario is in natural consistency with the internal-collision-induced magnetic reconnection and turbulence framework, which invokes many minijets due to local magnetic reconnection that constantly appear and disappear in a global magnetically dominated jet.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"172 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Stability of Interstellar Neutral Hydrogen Clouds at Large Z-heights","authors":"G. L. Verschuur","doi":"10.3847/1538-4357/add335","DOIUrl":"https://doi.org/10.3847/1538-4357/add335","url":null,"abstract":"Galactic neutral hydrogen (H i) data drawn from several large-scale surveys have been used to study 32 small clouds found between Galactic longitudes 70° and 140° and latitudes −20° and −45°. This places them below the Perseus spiral arm in the second quadrant of Galactic longitude. The velocities of the sample range from −30 to −57 km s−1, and their z-heights are between −1.5 and −3.7 kpc. The mapped clouds are localized brightness enhancements along the length of interstellar H i filaments. This H i may have been propelled into the Galactic halo by the action of many supernovae and stellar winds originating in the abundant star-forming regions in this longitude region of the Perseus spiral arm. Adopting this model allows the distance to each cloud to be derived. Their emission profiles are characterized by narrow lines ≈5 km s−1 wide. Application of the virial theorem for the ensemble of features indicates that an average magnetic field of 1.0 ± 0.4 μG can balance internal pressure.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eccentric Features in the Gravitational-wave Phase of Dynamically Formed Black Hole Binaries","authors":"Kai Hendriks, Lorenz Zwick and Johan Samsing","doi":"10.3847/1538-4357/adcb35","DOIUrl":"https://doi.org/10.3847/1538-4357/adcb35","url":null,"abstract":"We study the gravitational-wave (GW) phase shift arising from center-of-mass accelerations of binary black hole (BBH) mergers formed dynamically in three-body systems, where both the inner orbit of the merging binary and the outer orbit are eccentric. We provide a semi-analytical model and several analytical approximations that allow for fast evaluation of both the temporal evolution and the maximum value of the phase shift. The highest phase shifts occur when the binary merges close to the pericenter of the outer orbit, and can in this case be orders of magnitude larger compared to the circular limit. At high outer-orbit eccentricities, the orbital curvature leaves distinct imprints on the phase shift if the binary passes the outer pericenter during its inspiral. By comparing with phase shifts measured in numerical chaotic three-body scatterings, we show that our model accurately describes the observed phase of dynamically assembled binary systems in realistic astrophysical scenarios, providing a way to directly determine their formation channel via single GW observations. Phase shifts produced in such environments may receive additional amplifications due to the tidal pull from the perturber on the BBH.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"148 1","pages":"252"},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing the Accretion Flow in M87*: Insights from Faraday Rotation","authors":"Constanza Echiburú-Trujillo and Jason Dexter","doi":"10.3847/1538-4357/adcec1","DOIUrl":"https://doi.org/10.3847/1538-4357/adcec1","url":null,"abstract":"The Faraday rotation measure (RM) is a commonly used tool to trace electron number density and magnetic fields in hot accretion flows, particularly in low-luminosity accreting supermassive black holes. We focus on the nuclear region of M87, which was observed at 230 GHz (1.3 mm) by the Event Horizon Telescope in 2019. It remains unclear whether this emission originates from the accretion flow, the jet base, or both. To probe the presence of an accretion flow, we explore the scenario where the linearly polarized emission from the counter jet, visible at 43 GHz (7 mm), is Faraday-rotated by the accretion flow. We calculate theoretical predictions for counter-jet polarization using analytical and numerical models. In all cases, we find a Faraday-thick flow at 43 GHz (7 mm), with RM ∼ 106 rad m−2, and a polarization angle that follows a linear relationship with wavelength squared, consistent with external Faraday rotation. The more realistic model, which includes turbulence and magnetic field fluctuations, predicts that the polarization pattern should be time-dependent, and that the counter-jet emission is depolarized due to Faraday depth fluctuations across the accretion flow. Despite the Faraday thick regime and strong depolarization, the linear relationship persists, enabling us to constrain the flow’s physical properties. Comparing the counter-jet and forward-jet linear polarization states should enable detection of M87’s accretion flow and provide lower limits on electron density, magnetic field strength, and mass accretion rate.","PeriodicalId":501813,"journal":{"name":"The Astrophysical Journal","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144165494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}