The Astrophysical Journal Letters最新文献

{"title":"Where Have All the Little Red Dots Gone? Supermassive Black Hole Binary Dynamics and Its Impact on Galaxy Properties","authors":"Fazeel Mahmood Khan, Benjamin L. Davis, Andrea Valerio Macciò and Kelly Holley-Bockelmann","doi":"10.3847/2041-8213/adda4c","DOIUrl":"https://doi.org/10.3847/2041-8213/adda4c","url":null,"abstract":"Recent James Webb Space Telescope observations have revealed a peculiar class of galaxies at redshifts z ≳ 6, characterized by extremely high central stellar densities and overmassive central supermassive black holes (SMBHs), “little red dots” (LRDs). A critical question remains: if LRDs were common at high redshifts, how would they evolve into local elliptical galaxies with significantly lower central densities? To address this, we performed direct N-body simulations of LRD mergers, focusing on the coevolution of host galaxies and central SMBHs. We track the complete evolution of SMBH binaries into the three-body hardening and gravitational-wave (GW) emission phase. Our results demonstrate that during galaxy mergers, the central SMBHs can eject a substantial amount of mass from the galactic core via the three-body slingshot effect, leading to a decrease in central stellar surface density by an order of magnitude. Additionally, GW recoil can further contribute in making the galaxy centers less dense and more in alignment with low-redshift quiescent galaxies. This transformation occurs on a relatively short timescale of a few ∼100 Myr, implying that LRDs can evolve into lower-redshift elliptical galaxies by z < 4. The timescales for our SMBH mergers vary between 100 and 800 Myr, depending on the initial orbital parameters of the merging galaxies and the mass ratio of the SMBHs. Our findings provide a plausible mechanism for the transformation of LRDs into elliptical galaxies while highlighting the efficiency of SMBH mergers in such high-density environments, which plays a crucial role in SMBH growth.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144202035","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":"A Massive Black Hole 0.8 kpc from the Host Nucleus Revealed by the Offset Tidal Disruption Event AT2024tvd","authors":"Yuhan Yao, Ryan Chornock, Charlotte Ward, Erica Hammerstein, Itai Sfaradi, Raffaella Margutti, Luke Zoltan Kelley, Wenbin Lu, Chang Liu, Jacob Wise, Jesper Sollerman, Kate D. Alexander, Eric C. Bellm, Andrew J. Drake, Christoffer Fremling, Marat Gilfanov, Matthew J. Graham, Steven L. Groom, K. R. Hinds, S. R. Kulkarni, Adam A. Miller, James C. A. Miller-Jones, Matt Nicholl, Daniel A. Perley, Josiah Purdum, Vikram Ravi, R. Michael Rich, Nabeel Rehemtulla, Reed Riddle, Roger Smith, Robert Stein, Rashid Sunyaev, Sjoert van Velzen and Avery Wold","doi":"10.3847/2041-8213/add7de","DOIUrl":"https://doi.org/10.3847/2041-8213/add7de","url":null,"abstract":"Tidal disruption events (TDEs) that are spatially offset from the nuclei of their host galaxies offer a new probe of massive black hole (MBH) wanderers, binaries, triples, and recoiling MBHs. Here we present AT2024tvd, the first off-nuclear TDE identified through optical sky surveys. High-resolution imaging with the Hubble Space Telescope shows that AT2024tvd is 0 914 ± 0 010 offset from the apparent center of its host galaxy, corresponding to a projected distance of 0.808 ± 0.009 kpc at z = 0.045. Chandra and Very Large Array observations support the same conclusion for the TDE’s X-ray and radio emission. AT2024tvd exhibits typical properties of nuclear TDEs, including a persistent hot UV/optical component that peaks at Lbb ∼ 6 × 1043 erg s−1, broad hydrogen lines in its optical spectra, and delayed brightening of luminous (LX,peak ∼ 3 × 1043 erg s−1), highly variable soft X-ray emission. The MBH mass of AT2024tvd is 106±1M⊙, at least 10 times lower than its host galaxy’s central black hole mass (≳108M⊙). The MBH in AT2024tvd has two possible origins: a wandering MBH from the lower-mass galaxy in a minor merger during the dynamical friction phase or a recoiling MBH ejected by triple interactions. Combining AT2024tvd with two previously known off-nuclear TDEs discovered in X-rays (3XMM J2150 and EP240222a), which likely involve intermediate-mass black holes in satellite galaxies, we find that the parent galaxies of all three events are very massive (∼1010.9M⊙). This result aligns with expectations from cosmological simulations that the number of offset MBHs scales linearly with the host halo mass.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"77 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144202037","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":"Model-independent H 0 within FLRW: Joint Constraints from GWTC-3 Standard Sirens and Strong Lensing Time Delays","authors":"Ji-Yu Song, Jing-Zhao Qi, Jing-Fei Zhang and Xin Zhang","doi":"10.3847/2041-8213/add999","DOIUrl":"https://doi.org/10.3847/2041-8213/add999","url":null,"abstract":"We use 47 gravitational-wave (GW) standard sirens from the third Gravitational-Wave Transient Catalog to calibrate distances in the strong gravitational lensing (SGL) system RXJ1131-1231 and constrain the Hubble constant (H0) via the distance sum rule, without assuming a specific cosmological model. For ΩK = 0, we obtain km s−1 Mpc−1 and km s−1 Mpc−1 by breaking the mass-sheet transform using lens galaxy’s mass model and stellar kinematics, respectively. Allowing ΩK to vary increases the central value of H0 and reduces its precision. We find that GW dark sirens have significant potential for calibrating SGL systems, due to their relatively higher redshifts. By combining 42 binary black holes and RXJ1131-1231, we obtain an H0 constraint with a precision approximately 40% better than the measurement from GW170817 using the Hubble law. This suggests that high-precision, model-independent H0 measurements can be achieved with this method as the redshift range of GW dark sirens expands, even without the need for GW bright sirens.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177011","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":"Gravitational-wave Parameter Estimation in Non-Gaussian Noise Using Score-based Likelihood Characterization","authors":"Ronan Legin, Maximiliano Isi, Kaze W. K. Wong, Yashar Hezaveh and Laurence Perreault-Levasseur","doi":"10.3847/2041-8213/add681","DOIUrl":"https://doi.org/10.3847/2041-8213/add681","url":null,"abstract":"Gravitational-wave (GW) parameter estimation typically assumes that instrumental noise is Gaussian and stationary. Obvious departures from this idealization are typically handled on a case-by-case basis, e.g., through bespoke procedures to “clean” non-Gaussian noise transients (glitches), as was famously the case for the GW170817 neutron-star binary. Although effective, this data manipulation can bias key astrophysical inferences, such as binary precession, and compound unpredictably when combining multiple observations. Alternative bias-free methods, like joint noise-signal inference, remain too computationally expensive for large-scale execution. Here we take a different approach: rather than explicitly modeling individual non-Gaussianities to then apply the traditional GW likelihood, we seek to learn the true distribution of instrumental noise without presuming Gaussianity and stationarity in the first place. Assuming only noise additivity, we employ score-based diffusion models to learn an empirical noise distribution directly from detector data and then combine it with a deterministic waveform model to provide an unbiased estimate of the likelihood function. We validate the method by performing inference on a subset of GW parameters from 400 mock observations, containing real LIGO noise from either the Livingston or Hanford detectors. We show that the proposed method can recover the true parameters even in the presence of loud glitches, and that the inference is unbiased over a population of signals without applying any cleaning to the data. This work provides a promising avenue for extracting unbiased source properties in future GW observations over the coming decade.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"90 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177010","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":"It’s Not Just a Phase: Oblique Pulsations in Magnetic Red Giants and Other Stochastic Oscillators","authors":"Nicholas Z. Rui, Jim Fuller and J. M. Joel Ong","doi":"10.3847/2041-8213/add5e2","DOIUrl":"https://doi.org/10.3847/2041-8213/add5e2","url":null,"abstract":"Magnetic fields play a significant role in stellar evolution. In the last few years, asteroseismology has enabled the measurement of strong magnetic fields 104–106 G in the cores of dozens of red giants and is the only known way to directly measure internal stellar magnetic fields. However, current data are still interpreted assuming that these fields are too weak or too axisymmetric to affect the orientation of the pulsations (i.e., make the pulsations “oblique”), rendering stronger field strengths beyond the reach of existing asteroseismic searches. We show that, even when an oblique pulsator is also stochastic (such as in a red giant with a strong nonaxisymmetric magnetic field), geometric effects will cause the signal to contain frequency components that remain in perfect relative phase with each other. This perfect phase relationship persists even over timescales in which stochasticity erases absolute phase information. This perfect relative coherence is a distinctive observational signature of oblique pulsation that does not require a model for mode frequencies to search for. However, due to its dependence on phase, this effect will not be evident in the power spectral density alone, and phase information should be retained in order to detect it. Coherence-based searches for oblique pulsations may pave the way to measurements of magnetic fields of currently inaccessible strengths in red giants, as well as some main-sequence and compact pulsators.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177009","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":"Retention of Surface Water on Tidally Locked Rocky Planets in the Venus Zone around M Dwarfs","authors":"Yueyun Ouyang, Feng Ding, 峰 丁, Jun Yang and 军 杨","doi":"10.3847/2041-8213/adda4b","DOIUrl":"https://doi.org/10.3847/2041-8213/adda4b","url":null,"abstract":"Terrestrial planets within the Venus zone surrounding M-dwarf stars can retain surface ice caps on the perpetual dark side if atmospheric heat transport is inefficient, as suggested by previous global climate simulations. This condition is proposed to play a role in the potential regional habitability of these planets. However, the amount of surface ice may be limited by considering the water condensed from the steam atmosphere in a runaway greenhouse state, and the physical mechanism for triggering the condensation process is not clear. Here, we use a two-column moist radiative–convective–subsiding model to investigate the water condensation process on tidally locked planets from the runaway greenhouse state. We find that the water condensation process is characterized by two distinct equilibrium states under the same incoming stellar flux. The initiation of condensation corresponds to a warm, unstable state exhibiting positive Planck feedback, whereas the termination phase corresponds to a cold, stable state exhibiting negative Planck feedback. We further show that the surface water mass in the collapsed state decreases with the incoming stellar flux, background surface pressure, and optical thickness of noncondensable greenhouse gases, with a global equivalent depth of less than ∼20 cm. Our two-column approach provides a straightforward way to understand the water evolution on Venus zone planets around M dwarfs.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","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":"144177012","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":"Formation of Chromospheric Fan-shaped Jets through Magnetic Reconnection","authors":"Annu Bura, Tanmoy Samanta, Avijeet Prasad, Ronald L. Moore, Alphonse C. Sterling, Vasyl Yurchyshyn and Arun Surya","doi":"10.3847/2041-8213/add340","DOIUrl":"https://doi.org/10.3847/2041-8213/add340","url":null,"abstract":"Recurrent chromospheric fan-shaped jets highlight the highly dynamic nature of the solar atmosphere. They have been named as “light walls” or “peacock jets” in high-resolution observations. In this study, we examined the underlying mechanisms responsible for the generation of recurrent chromospheric fan-shaped jets utilizing data from the Goode Solar Telescope at Big Bear Solar Observatory, along with data from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory. These jets appear as dark elongated structures in Hα wing images, persist for over an hour, and are located in the intergranular lanes between a pair of same-polarity sunspots. Our analysis reveals that magnetic flux cancellation at the jet base plays a crucial role in their formation. HMI line-of-sight magnetograms show a gradual decrease in opposite-polarity fluxes spanning the sequence of jets in Hα−0.8 Å images, suggesting that recurrent magnetic reconnection, likely driven by recurrent miniature flux-rope eruptions that are built up and triggered by flux cancellation, powers these jets. Additionally, magnetic field extrapolations reveal a 3D magnetic null-point topology at the jet formation site ∼1.25 Mm height. Furthermore, we observed strong brightening in the AIA 304 Å channel above the neutral line. Based on our observations and extrapolation results, we propose that these recurrent chromospheric fan-shaped jets align with the minifilament eruption model previously proposed for coronal jets. Though our study focuses on fan-shaped jets in between same-polarity sunspots, a similar mechanism might be responsible for light-bridge-associated fan-shaped jets.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177008","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":"Magnetic Reconnection–driven Energization of Protons up to ∼400 keV at the Near-Sun Heliospheric Current Sheet","authors":"M. I. Desai, J. F. Drake, T. Phan, Z. Yin, M. Swisdak, D. J. McComas, S. D. Bale, A. Rahmati, D. Larson, W. H. Matthaeus, M. A. Dayeh, M. J. Starkey, N. E. Raouafi, D. G. Mitchell, C. M. S. Cohen, J. R. Szalay, J. Giacalone, M. E. Hill, E. R. Christian, N. A. Schwadron, R. L. McNutt, O. Malandraki, P. Whittlesey, R. Livi and J. C. Kasper","doi":"10.3847/2041-8213/ada697","DOIUrl":"https://doi.org/10.3847/2041-8213/ada697","url":null,"abstract":"We report observations of direct evidence of energetic protons being accelerated above ∼400 keV within the reconnection exhaust of a heliospheric current sheet (HCS) crossing by NASA’s Parker Solar Probe (PSP) at a distance of ∼16.25 solar radii (Rs) from the Sun. Inside the exhaust, both the reconnection-generated plasma jet and the accelerated protons up to ∼400 keV propagated toward the Sun, unambiguously establishing their origin from HCS reconnection sites located antisunward of PSP. Within the core of the exhaust, PSP detected stably trapped energetic protons up to ∼400 keV, which is ≈1000 times greater than the available magnetic energy per particle. The differential energy spectrum of the accelerated protons behaved as a pure power law with spectral index of ∼−5. Supporting simulations using the kglobal model suggest that the trapping and acceleration of protons up to ∼400 keV in the reconnection exhaust are likely facilitated by merging magnetic islands with a guide field between ∼0.2 and 0.3 of the reconnecting magnetic field, consistent with the observations. These new results, enabled by PSP’s proximity to the Sun, demonstrate that magnetic reconnection in the HCS is a significant new source of energetic particles in the near-Sun solar wind. Our findings of in situ particle acceleration via magnetic reconnection at the HCS provide valuable insights into this fundamental process, which frequently converts the large magnetic field energy density in the near-Sun plasma environment and may be responsible for heating the Sun’s atmosphere, accelerating the solar wind, and energizing charged particles to extremely high energies in solar flares.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"25 1","pages":"L38"},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164913","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":"Exploring the Link between Fast Radio Burst and Binary Neutron Star Origins with Spaceborne Gravitational Wave Observations","authors":"Yu-xuan Yin, 宇轩 尹, En-kun Li, 恩坤 李, Bing Zhang, 冰 张, Yi-Ming Hu and 一鸣 胡","doi":"10.3847/2041-8213/add875","DOIUrl":"https://doi.org/10.3847/2041-8213/add875","url":null,"abstract":"The origin of repeating fast radio bursts (rFRBs) is an open question, with observations suggesting that at least some are associated with old stellar populations. It has been proposed that some rFRBs may be produced by interactions of the binary neutron star (BNS) magnetospheres decades to centuries before the coalescence. These systems would also emit centi-Hertz gravitational waves during this period, which can be detectable by spaceborne gravitational wave detectors. We explore the prospects of using current and future spaceborne gravitational wave detectors, such as TianQin, LISA, and DECIGO, to test this fast radio burst (FRB) formation hypothesis. Focusing on nearby galaxies like M81, which hosts an rFRB source in a globular cluster, we calculate the detection capabilities for BNS systems. Our analysis reveals that while missions like TianQin and LISA face limitations in horizon distance, changing the detector pointing direction could significantly enhance detection probabilities. Considering that the chance of a Milky Way–like galaxy coincidentally containing a BNS within 100 yr before merger is only 3 × 10−5–5 × 10−3, if a signal is detected originating from M81, we can establish the link between FRBs and BNSs with a significance level of at least 2.81σ. For TianQin and LISA, Bayes factors for rFRB–BNS associations range from 4 × 106 to 7 × 108 under ideal assumptions of uniform event distribution, dropping to 5 × 102–105 when accounting for the fact that the events are confined in galaxies. Next-generation detectors such as DECIGO offer enhanced capabilities compared to TianQin and LISA and should easily detect these systems in M81 and beyond. DECIGO can boost the Bayes factor by up to 4 orders of magnitude (1010–1012 ideally and 104–106 realistically). Our work highlights the critical role of spaceborne gravitational wave missions in unraveling FRB origins.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164921","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":"X-Ray Polarization of the Magnetar 1E 1841−045","authors":"Rachael Stewart, George A. Younes, Alice K. Harding, Zorawar Wadiasingh, Matthew G. Baring, Michela Negro, Tod E. Strohmayer, Wynn C. G. Ho, Mason Ng, Zaven Arzoumanian, Hoa Dinh Thi, Niccolò Di Lalla, Teruaki Enoto, Keith Gendreau, Chin-Ping Hu, Alex van Kooten, Chryssa Kouveliotou and Alexander McEwen","doi":"10.3847/2041-8213/adbffa","DOIUrl":"https://doi.org/10.3847/2041-8213/adbffa","url":null,"abstract":"We report on IXPE and NuSTAR observations beginning 40 days after the 2024 outburst onset of magnetar 1E 1841−045, marking the first IXPE observation of a magnetar in an enhanced state. Our spectropolarimetric analysis indicates that both a blackbody (BB) plus double power-law (PL) and a double blackbody plus power-law spectral model fit the phase-averaged intensity data well, with a hard PL tail (Γ = 1.19 and 1.35, respectively) dominating above ≈5 keV. For the former model, we find the soft PL (the dominant component at soft energies) exhibits a polarization degree (PD) of ≈30% while the hard PL displays a PD of ≈40%. Similarly, the cool BB of the 2BB+PL model possesses a PD of ≈15% and a hard PL PD of ≈57%. For both models, each component has a polarization angle (PA) compatible with celestial north. Model-independent polarization analysis supports these results, wherein the PD increases from ≈15% to ≈70% in the 2–3 keV and 6–8 keV ranges, respectively, while the PA remains nearly constant. We find marginal evidence for phase-dependent variability of the polarization properties, namely a higher PD at phases coinciding with the hard X-ray pulse peak. We compare the hard X-ray PL to the expectation from resonant inverse Compton scattering (RICS) and secondary pair cascade synchrotron radiation from primary high-energy RICS photons; both present reasonable spectropolarimetric agreement with the data, albeit the latter does so more naturally. We suggest that the soft PL X-ray component may originate from a Comptonized corona in the inner magnetosphere.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"152 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144153611","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}