The Astrophysical Journal Letters最新文献

Sensitivity to Sub-Io-sized Exosatellite Transits in the MIRI LRS Light Curve of the Nearest Substellar Worlds 最近的次恒星世界的MIRI LRS光曲线对亚io大小的外卫星凌日的敏感性

The Astrophysical Journal Letters Pub Date : 2025-10-09 DOI: 10.3847/2041-8213/ae09ab

Andrew Householder, Mary Anne Limbach, Beth Biller, Brooke Kotten, Mikayla J. Wilson, Johanna M. Vos, Andrew Skemer, Andrew Vanderburg, Ben J. Sutlieff, Xueqing Chen, Ian J. M. Crossfield, Nicolas Crouzet, Trent Dupuy, Jacqueline Faherty, Pengyu Liu, Elena Manjavacas, Allison McCarthy, Caroline V. Morley, Philip S. Muirhead, Natalia Oliveros-Gomez, Genaro Suárez, Xianyu Tan and Yifan Zhou

{"title":"Sensitivity to Sub-Io-sized Exosatellite Transits in the MIRI LRS Light Curve of the Nearest Substellar Worlds","authors":"Andrew Householder, Mary Anne Limbach, Beth Biller, Brooke Kotten, Mikayla J. Wilson, Johanna M. Vos, Andrew Skemer, Andrew Vanderburg, Ben J. Sutlieff, Xueqing Chen, Ian J. M. Crossfield, Nicolas Crouzet, Trent Dupuy, Jacqueline Faherty, Pengyu Liu, Elena Manjavacas, Allison McCarthy, Caroline V. Morley, Philip S. Muirhead, Natalia Oliveros-Gomez, Genaro Suárez, Xianyu Tan and Yifan Zhou","doi":"10.3847/2041-8213/ae09ab","DOIUrl":"https://doi.org/10.3847/2041-8213/ae09ab","url":null,"abstract":"JWST’s unprecedented sensitivity enables precise spectrophotometric monitoring of substellar worlds, revealing atmospheric variability driven by mechanisms operating across different pressure levels. This same precision now permits exceptionally sensitive searches for transiting exosatellites—small terrestrial companions to these worlds. Using a novel simultaneous dual-band search method to address host variability, we present a search for transiting exosatellites in an 8 hr JWST/MIRI LRS light curve of the nearby (2.0 pc) substellar binary WISE J1049–5319 AB, composed of two ∼30 MJup brown dwarfs separated by 3.5 au and viewed nearly edge-on. Although we detect no statistically significant transits, our injection/recovery tests demonstrate sensitivity to satellites as small as 0.275 R⊕ (0.96 RIo or ∼1 lunar radius), corresponding to 300 ppm transit depths, and satellite-to-host mass ratios >10−6. This approach paves the way for detecting Galilean moon analogs around directly imaged brown dwarfs, free-floating planets, and wide-orbit exoplanets, dozens of which are already scheduled for JWST light-curve monitoring. In our solar system, each giant planet hosts on average 3.5 moons above this threshold, suggesting that JWST now probes a regime where such companions are expected to be abundant. The technique and sensitivities demonstrated here mark a critical step toward detecting exosatellites and ultimately enabling constraints on the occurrence rates of small terrestrial worlds orbiting 1–70 MJup hosts.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"87 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145255726","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}

引用次数: 0

Observational Evidence for Spin Alignment between Galaxy Groups and Their Central Galaxies 星系群及其中心星系自旋排列的观测证据

The Astrophysical Journal Letters Pub Date : 2025-10-09 DOI: 10.3847/2041-8213/ae0ca5

Peng Wang and 鹏王

{"title":"Observational Evidence for Spin Alignment between Galaxy Groups and Their Central Galaxies","authors":"Peng Wang and 鹏王","doi":"10.3847/2041-8213/ae0ca5","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0ca5","url":null,"abstract":"We present a systematic observational study of the spin alignment between galaxy groups and their central galaxies using a large spectroscopic sample from the Sloan Digital Sky Survey. Unlike previous studies based on morphology or major axis alignment, we use spin as a direct, dynamically motivated probe. To match the limitations of observational data, the group spin, central-galaxy spin, and alignment angle are defined and measured in projection on the sky plane. By applying two novel spin estimators for galaxy groups, we find strong statistical evidence for a preferential alignment, with a mean projected angle of 34 17 ± 0 29, significantly deviating from random expectation at 37.77σ. This alignment signal persists across a wide range of group and galaxy properties, but its strength is modulated by mass, morphology, and color. Specifically, we find that more massive groups and more massive central galaxies exhibit stronger alignment. Furthermore, elliptical central galaxies show stronger alignment than spirals, and bluer central galaxies are more strongly aligned than redder ones. Our results suggest a close dynamical link between the spin of central galaxies and their host groups, modulated by their physical properties and star formation history. These results provide new insights into the dynamical connection between central galaxies and their host dark matter halos.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"110 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145255606","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}

引用次数: 0

Population-dependent r-process Scatter in the Globular Cluster M15 球状星团M15中种群依赖的r-过程散射

The Astrophysical Journal Letters Pub Date : 2025-10-08 DOI: 10.3847/2041-8213/ae0a4a

Lauren E. Henderson, Roman Gerasimov and Evan N. Kirby

引用次数: 0

A Dense Molecular Ringlike Structure in Gaseous CO Depletion Region G34.74−0.12 气体CO枯竭区G34.74−0.12致密环状分子结构

The Astrophysical Journal Letters Pub Date : 2025-10-08 DOI: 10.3847/2041-8213/ae0579

Shuting Lin, Siyi Feng, Fengwei Xu, Ke Wang, Patricio Sanhueza, Junzhi Wang, Zhi-Yu Zhang, Yichen Zhang, Kaho Morii, Hauyu Baobab Liu, Sheng-Yuan Liu, Lile Wang, Giovanni Sabatini, Hui Li, Willem Baan, Zhi-Kai Zhu and Shanghuo Li

{"title":"A Dense Molecular Ringlike Structure in Gaseous CO Depletion Region G34.74−0.12","authors":"Shuting Lin, Siyi Feng, Fengwei Xu, Ke Wang, Patricio Sanhueza, Junzhi Wang, Zhi-Yu Zhang, Yichen Zhang, Kaho Morii, Hauyu Baobab Liu, Sheng-Yuan Liu, Lile Wang, Giovanni Sabatini, Hui Li, Willem Baan, Zhi-Kai Zhu and Shanghuo Li","doi":"10.3847/2041-8213/ae0579","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0579","url":null,"abstract":"We report the discovery of a dense molecular ringlike structure in a dense (105 cm−3), cold (parsec-scale CO depletion at a factor of 5), and young (104 yr) star-forming region G34.74−0.12, revealed by C18O (2−1), HNC (1−0), and N2H+ (1−0) observations with the Atacama Large Millimeter/submillimeter Array. The ringlike structure is redshifted with respect to the clump, spanning from Vsys,lsr + 0.9 to Vsys,lsr + 2.9 km s−1, with a total mass of 109 M⊙. It is spatially coincident with 1.3 and 3.0 mm dust continuum emission from the cores, and several protostellar outflows. However, no free–free emission or H ii region is detected in association with this structure. With a slow expansion speed indicated by the position–velocity diagram, this ring structure differs from rings previously identified in more evolved star-forming regions. Possible explanations for the ring-like structure include a relic windblown bubble produced by a deeply embedded young stellar object, a hollow cavity formed by cloud–cloud interactions, a gas ring resulting from a temperature gradient, or a line-of-sight superposition of multiple outflows or dense clouds. This discovery offers a rare observational glimpse into the earliest dynamical processes involved in massive star formation.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145246743","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}

引用次数: 0

A Disk-originated 329 Day Quasiperiodic Oscillation in the Seyfert 1 Galaxy J1626+5120 Seyfert 1星系J1626+5120中盘源的329天准周期振荡

The Astrophysical Journal Letters Pub Date : 2025-10-08 DOI: 10.3847/2041-8213/ae0b57

Litao Zhu, Zhongxiang Wang, Dong Zheng, Alok C. Gupta and Ju-Jia Zhang

{"title":"A Disk-originated 329 Day Quasiperiodic Oscillation in the Seyfert 1 Galaxy J1626+5120","authors":"Litao Zhu, Zhongxiang Wang, Dong Zheng, Alok C. Gupta and Ju-Jia Zhang","doi":"10.3847/2041-8213/ae0b57","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0b57","url":null,"abstract":"The Seyfert 1 galaxy J1626+5120 is estimated to host a 108M⊙ black hole (BH) accreting at Eddington ratio . Its long-term multiband light-curve data show flicker-like variations, but in a well-sampled g-band light curve, we are able to determine a ≃329 day quasiperiodic oscillation (QPO) at a ∼4.53σ significance. Six optical spectra were obtained for the source, three of which were taken by us. The spectra show that the variations were mainly because of flux changes blueward of 4000 Å. We also analyze X-ray and ultraviolet (UV) data obtained with the Neil Gehrels Swift Observatory (Swift), which targeted the source in the past 2 yr. X-ray and UV emissions of the source show variations correlated with optical. Time lags of four UV bands and four optical bands are determined with respect to the X-ray emission, which are consistent with a continuum reprocessing disk model. These properties point out a disk origin for the QPO, likely due to Lense–Thirring (LT) precession of the accretion flow at ∼20 gravitational radii of the BH. This QPO could be a key case linking subyear-long QPOs in jets, which have more cases reported, to LT precession.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145246772","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}

引用次数: 0

The Type II SN 2025pht in NGC 1637: A Red Supergiant with Carbon-rich Circumstellar Dust as the First JWST Detection of a Supernova Progenitor Star NGC 1637中的II型SN 2025pht：一颗富含碳的星周尘埃的红超巨星，是JWST首次探测到的超新星祖星

The Astrophysical Journal Letters Pub Date : 2025-10-07 DOI: 10.3847/2041-8213/ae04de

Charles D. Kilpatrick, Aswin Suresh, Kyle W. Davis, Maria R. Drout, Ryan J. Foley, Alexander Gagliano, Wynn V. Jacobson-Galán, Ravjit Kaur, Kirsty Taggart and Jason Vazquez

{"title":"The Type II SN 2025pht in NGC 1637: A Red Supergiant with Carbon-rich Circumstellar Dust as the First JWST Detection of a Supernova Progenitor Star","authors":"Charles D. Kilpatrick, Aswin Suresh, Kyle W. Davis, Maria R. Drout, Ryan J. Foley, Alexander Gagliano, Wynn V. Jacobson-Galán, Ravjit Kaur, Kirsty Taggart and Jason Vazquez","doi":"10.3847/2041-8213/ae04de","DOIUrl":"https://doi.org/10.3847/2041-8213/ae04de","url":null,"abstract":"We present follow-up imaging and spectroscopy and pre-explosion imaging of SN 2025pht located in NGC 1637 at 12 Mpc. Our spectroscopy shows that SN 2025pht is a Type II supernova (SN) with broad lines of hydrogen and with minimal line-of-sight extinction inferred from Na i D absorption. NGC 1637 was the target of several epochs of Hubble Space Telescope (HST) and James Webb Space Telescope (JWST) imaging covering the site of SN 2025pht from 31 to 0.7 yr prior to discovery. Using a follow-up HST image of SN 2025pht aligned to these data, we demonstrate that there is a credible progenitor candidate detected in multiple epochs of HST imaging and in JWST imaging from 1.3 to 8.7 μm, the first JWST counterpart to an SN and the longest-wavelength detection of an SN progenitor star. Fitting this source to red supergiant (RSG) spectral energy distributions (SEDs), we show that it is consistent with a RSG heavily reddened by circumstellar dust. The JWST photometry enables strong constraints on the nature of the circumstellar medium, and we find that the SED favors graphite-rich dust as opposed to silicate-rich dust and an optical circumstellar extinction of AV = 5.3 mag. We discuss the implications of a pre-SN RSG enshrouded in carbon-rich dust and this finding for the overall population of progenitor stars to Type II SNe, as well as the future of SN progenitor star discovery with JWST.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145241261","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}

引用次数: 0

Triples as Links between Binary Black Hole Mergers, Their Electromagnetic Counterparts, and Galactic Black Holes 三元组作为双黑洞合并、它们的电磁对应物和星系黑洞之间的联系

The Astrophysical Journal Letters Pub Date : 2025-10-07 DOI: 10.3847/2041-8213/ae0a20

Smadar Naoz, Zoltán Haiman, Eliot Quataert and Liz Holzknecht

{"title":"Triples as Links between Binary Black Hole Mergers, Their Electromagnetic Counterparts, and Galactic Black Holes","authors":"Smadar Naoz, Zoltán Haiman, Eliot Quataert and Liz Holzknecht","doi":"10.3847/2041-8213/ae0a20","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0a20","url":null,"abstract":"We propose a formation pathway linking black holes (BHs) observed in gravitational-wave (GW) mergers, wide BH–stellar systems uncovered by Gaia, and accreting low-mass X-ray binaries (LMXBs). In this scenario, a stellar-mass BH binary undergoes isolated binary evolution and merges while hosting a distant, dynamically unimportant tertiary stellar companion. The tertiary becomes relevant only after the merger, when the remnant BH receives a GW recoil kick. Depending on the kick velocity and system configuration, the outcome can be: (1) a bright electromagnetic (EM) counterpart to the GW merger; (2) an LMXB; (3) a wide BH–stellar companion system resembling the Gaia BH population; or (4) an unbound isolated BH. Modeling the three-body dynamics, we find that ∼0.02% of LIGO–Virgo–KAGRA (LVK) mergers may be followed by an EM counterpart within ∼10 days, produced by tidal disruption of the star by the BH. The flare is likely brightest in the optical–UV and lasts for days to weeks; in some cases, partial disruption causes recurring flares with a period of ∼2 months. We further estimate that this channel can produce ∼1%–10% of Gaia BH systems in the Milky Way. This scenario provides the first physically motivated link between GW sources, Gaia BHs, and some X-ray binaries, and predicts a rare but robust pathway for EM counterparts to binary BH mergers, potentially detectable in LVK’s O5 run.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145241262","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}

引用次数: 0

Observations of a Faint Nonthermal Onset before a GOES C-class Flare GOES c级耀斑前微弱非热爆发的观测

The Astrophysical Journal Letters Pub Date : 2025-10-06 DOI: 10.3847/2041-8213/ae0b58

Natália Bajnoková, Iain G. Hannah, Hannah Collier, Stephen M. White, Lindsay Glesener, Reed B. Masek, Marianne S. Peterson, Säm Krucker and Hugh S. Hudson

{"title":"Observations of a Faint Nonthermal Onset before a GOES C-class Flare","authors":"Natália Bajnoková, Iain G. Hannah, Hannah Collier, Stephen M. White, Lindsay Glesener, Reed B. Masek, Marianne S. Peterson, Säm Krucker and Hugh S. Hudson","doi":"10.3847/2041-8213/ae0b58","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0b58","url":null,"abstract":"We present an analysis of a GOES C1-class flare from 2022 September 6, which was jointly observed as occulted by Nuclear Spectroscopic Telescope ARray (NuSTAR) and on-disk by Spectrometer/Telescope for Imaging X-rays (STIX). NuSTAR observed faint coronal nonthermal emission as well as plasma heating >10 MK, starting 7 minutes prior to the flare. This onset emission implies that during this time, there is a continuous electron acceleration in the corona, which could also be responsible for the observed heating. The nonthermal model parameters remained consistent throughout the entire onset, indicating that the electron acceleration process persisted during this time. Furthermore, the onset coincided with a series of type III radio bursts observed by Long Wavelength Array-1, further supporting the presence of electron acceleration before the flare began. We also performed spectral analysis of the impulsive flare emission with STIX (thermal and footpoint emission). STIX footpoints and the onset coronal source were found to have similar electron distribution power-law indices, but with increased low-energy cut-off during the flare time. This could suggest that the nonthermal onset is an early signature of the acceleration mechanism that occurs during the main phase of the flare.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145241263","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}

引用次数: 0

The Impact of Alfvénic Shear Flow on Magnetic Reconnection and Turbulence alfv<s:1>剪切流对磁重联和湍流的影响

The Astrophysical Journal Letters Pub Date : 2025-10-06 DOI: 10.3847/2041-8213/ae0b56

Tamar Ervin, Alfred Mallet, Stefan Eriksson, M. Swisdak, James Juno, Orlando M. Romeo, Tai Phan, Trevor A. Bowen, Roberto Livi, Phyllis L. Whittlesey, Davin E. Larson and Stuart D. Bale

{"title":"The Impact of Alfvénic Shear Flow on Magnetic Reconnection and Turbulence","authors":"Tamar Ervin, Alfred Mallet, Stefan Eriksson, M. Swisdak, James Juno, Orlando M. Romeo, Tai Phan, Trevor A. Bowen, Roberto Livi, Phyllis L. Whittlesey, Davin E. Larson and Stuart D. Bale","doi":"10.3847/2041-8213/ae0b56","DOIUrl":"https://doi.org/10.3847/2041-8213/ae0b56","url":null,"abstract":"Magnetic reconnection is a fundamental and omnipresent energy conversion process in plasma physics. Novel observations of fields and particles from Parker Solar Probe (PSP) have shown the absence of reconnection in a large number of current sheets in the near-Sun solar wind. Using near-Sun observations from PSP encounters 4–11 (2020 January–2022 March), we investigate whether reconnection onset might be suppressed by velocity shear. We compare estimates of the tearing mode growth rate in the presence of shear flow for time periods identified as containing reconnecting current sheets versus nonreconnecting times, finding systematically larger growth rates for reconnection periods. Upon examination of the parameters associated with reconnection onset, we find that 85% of the reconnection events are embedded in slow, non-Alfvénic wind streams. We compare with fast, slow non-Alfvénic, and slow Alfvénic streams, finding that the growth rate is suppressed in highly Alfvénic fast and slow wind, and reconnection is not seen in these wind types, as would be expected from our theoretical expressions. These wind streams have strong Alfvénic flow shear, consistent with the idea of reconnection suppression by such flows. This could help explain the frequent absence of reconnection events in the highly Alfvénic, near-Sun solar wind observed by PSP. Finally, we find a steepening of both the trace and magnitude magnetic field spectra within reconnection periods in comparison to ambient wind. We tie this to the dynamics of relatively balanced turbulence within these reconnection periods and the potential generation of compressible fluctuations.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145235185","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}

引用次数: 0

Electromagnetic Energy Extraction from Kerr Black Holes: Ab Initio Calculations 克尔黑洞的电磁能量提取：从头算

The Astrophysical Journal Letters Pub Date : 2025-10-05 DOI: 10.3847/2041-8213/ae06a6

Claudio Meringolo, Filippo Camilloni and Luciano Rezzolla

引用次数: 0