arXiv subjects

Wenwen Zuo

Publications and source records attributed to Wenwen Zuo.

At least 19 recordsLinked to original sources

arXiv2026

Empirical Near-Infrared Spectral Templates from SPHEREx: Disentangling AGN and Host-Galaxy Emission

SPHEREx conducts the first all-sky near-infrared spectral survey over 0.75-5.0 $\mu$m, spanning the transition from host-galaxy starlight to AGN-heated torus emission and enabling spectroscopic identification of active galactic nuclei (AGNs). We develop a data-driven framework combining weighted non-negative matrix factorization with forward modeling to learn empirical rest-frame templates from 2,777 normal galaxies and 1,064 AGNs in the North Ecliptic Pole (NEP) field. The resulting 14-component dictionary contains seven galaxy templates spanning stellar-population continua and nebular emission and seven AGN templates capturing emission lines and warm and hot torus continua, providing an additive, operational decomposition. Inferred near-infrared host fractions correlate with independent SDSS spectral and HSC imaging decompositions (at Pearson $r=0.68$ and $r=0.59$), comparable to the SDSS-HSC correlation ($r=0.66$) and supporting the reliability of the AGN-host separation. In the NEP deep field, the same templates recover redshifts with $|z_{\rm fit}-z_{\rm spec}| < 0.01$ for 93.0% of galaxies and 93.5% of AGNs and distinguish galaxies, narrow-line AGNs, and broad-line AGNs with 81.3% accuracy. At all-sky depth, classification retains 72.9% accuracy. The near-infrared coefficients also flag questionable DESI spectral classifications and redshifts, showing how SPHEREx complements optical spectroscopy. Learned directly from survey spectrophotometry and extending beyond the $K$ band, this empirical dictionary fills a long-standing gap in near-to-mid-infrared templates and provides a data-driven foundation for population-scale studies of AGN activity and its connection to host galaxies across the SPHEREx all-sky survey.

astro-ph.GA↗

arXiv2026

The Intermediate-Mass Black Hole Reverberation Mapping Project: Scientific Overview and Sample Characteristics

Recent discoveries with the James Webb Space Telescope of massive black holes at high redshift have highlighted fundamental questions about black hole seed formation and the coevolution of black holes with their host galaxies. Because the initial seed population cannot yet be observed directly, nearby intermediate-mass black holes provide a complementary fossil record of black hole formation and early growth. Motivated by this opportunity, we present the Intermediate-Mass Black Hole Reverberation Mapping (IMBH-RM) project and construct a homogeneous Sloan Digital Sky Survey sample of active broad-line IMBHs by uniformly reanalyzing literature candidates with consistent spectral decomposition and black hole mass estimation. Our sample contains 192 reliable IMBH candidates at $z\lesssim0.3$ with $\log(M_{\rm BH}/M_\odot)<6$, including four particularly compelling sources with $\log(M_{\rm BH}/M_\odot)<5$. The primary goal of IMBH-RM is to obtain reliable black hole masses from direct measurements and characteristic sizes of the broad-line region and accretion disk for a carefully selected subsample. These measurements will provide robust low-mass anchors for calibrating single-epoch black hole mass estimates and extending black hole--galaxy scaling relations into the IMBH regime. By building a statistically meaningful reverberation-mapped sample spanning $10^4-10^6\,M_\odot$, we aim to constrain the local IMBH mass distribution and place observational constraints on competing black hole seed formation scenarios. The future Multi-Channel Imager aboard the Chinese Space-station Survey Telescope provides a particularly promising platform for achieving these goals.

astro-ph.GA↗

arXiv2026

Constraints on the Intranight Optical Variability of Intermediate-Mass Black Hole Candidates

Intermediate-mass black holes (IMBHs) provide a unique regime for studying accretion variability at the low-mass end of the black hole population, yet their intranight optical variability (INOV) remains poorly constrained. We present a systematic investigation of INOV in an optically selected sample of IMBH candidates using high-cadence observations from the Zwicky Transient Facility (ZTF). From a parent sample of 1,447 broad H$\alpha$-selected candidates, we identify 64 IMBH candidates (median $f_{\mathrm{AGN}}\sim0.06$) with 163 intranight monitoring sessions. Apparent INOV signals identified by conventional ZTF PSF-fit photometry are largely associated with seeing-dependent changes in the relative contributions of compact nuclear and extended host components, which can mimic intrinsic short-timescale variability. In contrast, no robust INOV is detected with difference-image analysis. An ensemble structure function spanning $\Delta t\sim0.003$--$1600$ days reveals long-term variability in a small subsample of sources, whereas intrinsic variability remains unresolved at intranight timescales. Monte Carlo simulations further show that ZTF-like single-night monitoring has a low INOV recovery probability ($\sim1.2%$) for the variability amplitudes inferred from the long-term analysis. The recovery probability is primarily controlled by source brightness, AGN contribution, intrinsic variability amplitude, and photometric precision. These results demonstrate that the absence of detected INOV does not imply the absence of rapid accretion variability, but can reflect the limited detectability of low-amplitude signals under current observing capabilities. Our findings highlight the importance of robust photometric methodologies for future high-cadence variability studies of low-mass accreting black holes.

astro-ph.GA↗

arXiv2026

ASKAP discovery of a pair of large radio bubbles: on the origin of odd radio circles

We report the serendipitous discovery of a large, low-surface-brightness radio bubble in 944 MHz continuum data from the ASKAP Evolutionary Map of the Universe (EMU) survey. The structure, centred on the elliptical galaxy LEDA 217397 at a redshift of $z=0.040$, spans $\sim$8.4 arcmin, corresponding to a projected diameter of $\sim$399 kpc, and consists of two partly overlapping shells both with radii of $\sim$114 kpc. The integrated flux density of the bubble is $56.8\pm2.9$ mJy at 944 MHz, implying a rest-frame 1.4 GHz luminosity of $\sim$ $1.4\times10^{23}$ W Hz$^{-1}$. Combining the EMU measurement with MWA GLEAM-X data at 88--185 MHz, we derive a steep integrated spectral index of $\alpha=-1.04\pm0.04$, and a two-frequency spectral-index map suggesting a possible exterior flattening. Spectral Energy Distribution (SED) fitting indicates a massive ($\log M_{\ast}/M\odot = 10.97\pm0.09$), quiescent (SFR=$0.025\pm0.083\,M\odot$ yr$^{-1}$) early-type host with no mid-infrared AGN signature and no overdense environment. We compare the bubble with odd radio circles (ORCs) and large radio shells, and discuss three scenarios for its origin: a starburst-driven wind, a merger-driven shock, and AGN jet-inflated bubbles. The starburst wind is disfavoured on energetic grounds ($\gtrsim$$10^{59}$ erg required versus $\sim$$10^{8}$ yr electron lifetimes), and neither a halo-scale merger shock nor a spherical nuclear blast wave can explain the unusually regular, double-shell geometry; a bipolar nuclear outburst -- a relic AGN jet episode, possibly triggered by a supermassive-black-hole merger -- provides the most natural explanation, with later shocks possibly re-energising the plasma. Deeper broad-band radio, polarimetric, spectroscopic and X-ray observations are needed to confirm its nature.

astro-ph.GA↗

arXiv2026

Comprehensive Analysis of Optical brightness and Color Variability of Blazars in the ZTF Survey DR22

This study conducts a comprehensive analysis of brightness and color variability in blazars, utilizing over six years of quasi-simultaneous g-band and r-band data from 1149 sources in the ZTF Data Release 22 (DR22), including 589 BL Lacs and 560 FSRQs. We quantify the amplitude of variability and the fractional root mean square (rms) variability for each source and statistically assess the overall and short-term color behaviors across different subclasses; examine the distribution of brightness variability characteristics across different blazar types and investigate how the extent of variability correlates with color trends. We found BL Lacs tend to exhibit a BWB (bluer when brighter) trend, while FSRQs display a RWB (redder when brighter) trend; BL Lacs with negligible host-galaxy contamination exhibit a BWB trend fraction of 14.7% (68/462) compared to 2.3% (11/462) for RWB trend, while FSRQs show 8.8% (49/560) BWB trend versus 14.1% (79/560) RWB trend. By statistically investigating how color behavior depends on brightness state across different timescales, we find that brighter states in both BL Lacs and FSRQs are more likely to exhibit BWB trend. Our results also show that BL Lacs with a BWB trend exhibit higher variability than those with a RWB trend, whereas FSRQs with a RWB trend display significantly greater variability than those with a BWB trend. These results suggest that blazar color variability depends jointly on source type, brightness state, and variability amplitude, highlighting the complexity of color evolution in blazars.

astro-ph.CO↗

arXiv2026

The Intermediate-Mass Black Hole Reverberation Mapping Project: Stable Optical Continuum Lags of an IMBH in the Dwarf Galaxy NGC 4395 Over Years

NGC 4395 is a nearby dwarf spiral galaxy hosting an active galactic nucleus (AGN) powered by an intermediate-mass black hole (IMBH, $M_{\rm BH} \sim 10^{4}$--$10^{5}\,M_\odot$). Recent optical continuum reverberation mapping studies have suggested potential lag variations between different epochs, offering important clues to the physical mechanisms governing variability in the vicinity of the central black hole. We present continuous intranight multi-band photometric monitoring of NGC 4395 based on five nights of observations, including three nights from the Faulkes Telescope North (two of which are archival) and two new nights from Mephisto. This represents the first systematic investigation of optical continuum lag stability in a galaxy hosting a robustly confirmed IMBH. By applying difference-imaging techniques to both the new observations and the reprocessed archival data, we detect statistically significant optical inter-band lags of $\sim 5$--15 minutes, which increase monotonically with increasing wavelength. No obvious $u$-band lag excess is observed, implying a negligible fractional contribution from diffuse continuum (DC) emission to the optical continuum, in agreement with our spectral decomposition results. The inter-band lags remain stable over multi-year baselines. We suggest that this long-term lag stability may be related to the minor DC contribution, a relatively steady disk-corona structure, and the unusually high X-ray-to-optical luminosity ratio characteristic of low-luminosity AGNs, which likely allows X-ray reprocessing to dominate over other potential variability mechanisms. Future facilities like Gemini/SCORPIO, with its simultaneous optical-to-near-infrared coverage, will be ideally suited to play an important role in advancing this field.

astro-ph.GA↗

arXiv2026

Detection of optical quasi-periodic oscillation in the blazar 3C 454.3

We analyzed 19 years of $R$-band data of the blazar 3C 454.3 from the Whole Earth Blazar Telescope (WEBT) archive, along with new data from its members and from public archives such as those provided by the Small and Moderate Aperture Research Telescope System (SMARTS) and the Steward Observatory projects to search for quasi-periodic oscillations (QPOs). We detected a QPO of $\sim$ 433 days using Lomb-Scargle periodogram, which lasted from MJD 54980--58450 as detected by the weighted wavelet Z-transform technique, making it one of the most persistent QPOs ever detected in the optical regime. The phase dispersion minimization technique was also performed to further validate this QPO claim. We detected this signal at a global significance of $2.53σ$ across all methodologies. To explain the observed QPO, we have considered both models focused on the accretion disk around the super-massive black hole (SMBH), and those based purely on jet emissions. Plausible jet-based models involve a shock moving down the jet in a helical magnetic field, whereas the SMBH models could involve Lense-Thirring effect-induced jet precession or dual jets in a binary SMBH system. We introduce a novel approach to distinguish genuine QPOs from spurious signals arising from annual seasonal gaps, a common limitation of ground-based observations.

astro-ph.HE↗

arXiv2026

A systematic evaluation of vision-language models for observational astronomical reasoning tasks

Vision-language models (VLMs) are increasingly proposed as general-purpose tools for scientific data interpretation, yet their reliability on real astronomical observations across diverse modalities remains untested. We present AstroVLBench, a comprehensive benchmark comprising over 4,100 expert-verified instances across five tasks spanning optical imaging, radio interferometry, multi-wavelength photometry, time-domain light curves, and optical spectroscopy. Evaluating six frontier models, we find that performance is strongly modality-dependent: while one model (Gemini 3 Pro) emerges as the most consistently capable across tasks, task-specific strengths vary, and all models substantially underperform domain-specialized methods. Mechanistic ablations reveal that performance depends not only on directing attention to salient visual features but also on grounding those features in physical knowledge. Phenomenological prompts describing what to look for improve accuracy by sharpening model focus, but physical prompts explaining why those features matter perform better overall and yield more balanced classifications with reduced class-specific bias. Consistent with this picture, presenting the underlying one-dimensional measurements directly as numerical tables instead of rendered plots yields up to 13 percentage points improvement. Reasoning quality analysis further demonstrates that, without explicit physical grounding, models may reach correct predictions from phenomenologically plausible cues while providing physically imprecise justifications, establishing that accuracy alone is insufficient for trustworthy scientific deployment. These findings provide the first systematic, multi-modal baselines for VLMs in observational astronomy and identify the specific representation, grounding, and reasoning bottlenecks where current models fail.

cs.AI↗

arXiv2026

Evidence for a Delayed UV Counterpart to X-ray Quasi-periodic Eruptions in Ansky

X-ray quasi-periodic eruptions (QPEs) represent a novel population of extreme, repeating nuclear transients whose physical origins remain debated. A defining characteristic of QPEs has been their exclusive detection in the X-ray band, with a notable absence of correlated multi-wavelength counterparts. Here we report the first detection of a recurrent UV response temporally coupled to the X-ray QPE signal in the source Ansky/ZTF19acnskyy. The UV emission displays coherent periodic modulations over five consecutive cycles, systematically lagging the X-ray eruptions by $0.96^{+0.38}_{-0.39}$ days, with a cross-correlation coefficient of $r_{\rm max} \sim 0.6$. We suggest that the detectability of this corresponding signal may be enabled by Ansky's unusually long recurrence timescale, which could reduce the temporal smearing of the UV response seen in more rapid QPEs. The observed delay may correspond to a diffusion timescale associated with heated blobs. However, we cannot exclude the possibility that the lag corresponds to the light-crossing time associated with X-ray irradiation that originates near the central black hole and propagates to the outer UV-emitting region. While numerous QPE models have been proposed, any viable model for Ansky must be able to simultaneously explain the presence of a UV counterpart, its measured time lag, and the previously observed steadily increasing recurrence period.

astro-ph.HE↗

arXiv2026

Compton hump reverberation lag in the bright Seyfert 1 galaxy IC 4329A with NuSTAR

Recent reverberation delay measurements have moved beyond the 10 keV X-ray range, providing evidence for the Compton hump (a.k.a. reflection hump) in the lag spectra. We report the relativistic reverberation of the reflection hump in the bright Seyfert\,1 galaxy IC\,4329A based on a long {\it NuSTAR} observation. We find a delayed response of the 20--30 keV X-ray band, with a lag time of $\sim1825$ s at frequencies $0.5-1.5 \times 10^{-4}$ Hz. The lag amplitude drops to $\sim195$ s as the frequencies increase to $(1.5-10)\times10^{-4}$ Hz. Including IC\,4329A, so far five sources have been explored for reflection hump reverberation. We perform reverberation modelling of the 3--50 keV lag-energy spectra using the general relativistic transfer function code, which provides independent timing-based measurements of the black hole mass $M_{\rm BH}=1.37_{-0.36}^{+0.33}\times10^8~M_{\odot}$ and the coronal height $h=2.45_{-2.36}^{+1.92}~R_{\rm g}$ (with uncertainties at 90\% confidence). Within the uncertainties, the measured mass is found to be consistent with the previous finding. Furthermore, we undertake reflection spectroscopy to account for the hump feature and the associated relativistic effect using the time-averaged flux spectrum. Further sampling of the {\it NuSTAR} data (with a bin width of 0.2/0.4 keV below and above 10 keV) that reshapes the spectral resolution allows us to constrain the coronal temperature at $50.26_{-4.03}^{+5.58}$ keV -- consistent with the previous result from the combined {\it Suzaku} and {\it NuSTAR} data.

astro-ph.HE↗

arXiv2025

Antarctic TianMu Staring Observation Project I: Overview and Implementation of the Prototype Telescope

Wide-field rapid sky surveys serve as critical observational methods for time-domain astronomical research. The Antarctic region, with several months of continuous dark nights annually, is an ideal site for time-domain astronomical observations. The Antarctic TianMu Staring Observation Project aims to deploy a fleet of small telescopes, adopting an array observation model to conduct time-domain optical observations in Antarctica, featuring wide-sky coverage, high-cadence sampling, long-period staring, and simultaneous multi-band measurements. Considering the severe challenges optical telescopes face in Antarctica, including extremely low temperatures, unattended operation, and limited power supply and network transmission, we have designed and developed the Antarctic TianMu prototype telescope based on drift-scan charge-coupled device technology. In October 2022, our prototype (with an aperture of 18 cm), named AT-Proto was transported to Zhongshan Station in Antarctica aboard China's 39th Antarctic Research Expedition. It has since operated stably and reliably in the frigid environment for over two years, demonstrating the significant advantages of this technology in polar astronomical observations. The experimental observation results of AT-Proto provide a solid foundation for the subsequent construction of a time-domain astronomy observation array in Antarctica.

astro-ph.IM↗

arXiv2025

Observatory Science with eXTP

Scheduled for launch in 2030, the enhanced X-ray Timing and Polarization (eXTP) telescope is a Chinese space-based mission aimed at studying extreme conditions and phenomena in astrophysics. eXTP will feature three main payloads: Spectroscopy Focusing Arrays (SFAs), Polarimetry Focusing Arrays (PFAs), and a Wide-field Camera (W2C). This white paper outlines observatory science, incorporating key scientific advances and instrumental changes since the publication of the previous white paper [1]. We will discuss perspectives of eXTP on the research domains of flare stars, supernova remnants, pulsar wind nebulae, cataclysmic variables, X-ray binaries, ultraluminous X-ray sources, AGN, and pulsar-based positioning and timekeeping.

astro-ph.IM↗

arXiv2025

The Intermediate-Mass Black Hole Reverberation Mapping Project: First Detection of Mid-Infrared Lags in Prototypical IMBHs in NGC 4395 and POX 52

The search for robust evidence of intermediate-mass black holes (IMBHs) is crucial for understanding black hole seeding process and the formation of supermassive black holes in the early Universe. NGC 4395 and POX 52 are two prototypical IMBH hosts, both exhibiting multi-line evidence of low-mass black hole activity. Here, we report the first detection of mid-infrared (MIR) lags in response to optical variability, with measurements of $3.0^{+2.4}_{-1.9}$ days for NGC 4395 and $35.2^{+14.2}_{-11.7}$ days for POX~52 at $3.4$ $μ$m, respectively, using archival optical data and observations from the Wide-field Infrared Survey Explorer (WISE). This detection provides the first reverberation evidence of low-mass black hole activity in POX 52. The time lags of these two low-mass, low-luminosity active galactic nuclei (AGNs) generally follow the extent of the $R_{\rm dust}-L_{\rm 5100}$ relation found in higher-mass AGNs. Based on an empirical relation between the broad-line region and dusty torus size, we constrain the black hole mass of POX 52 to log($M_{\rm BH}$/$M_\odot$) = 5.5 $\pm$ 0.37 (systemic and statistical errors), confirming its IMBH nature. Furthermore, long-term optical continuum monitoring of POX 52 reveals a mild inter-band lag of $\lesssim$ 1 day. However, no significant intranight variability was detected during its one-night, high-cadence monitoring, which we attribute to the longer duty cycle of fast variability in POX 52 compared to that in NGC 4395.

astro-ph.GA↗

arXiv2025

First Detection of Radio Emission from the Intermediate Mass Black Hole in POX 52: Deep Multi-Band Observations with ATCA and VLA

We present the first multi-band centimeter detection of POX 52, a nearby dwarf galaxy believed to habor a robust intermediate mass black hole (IMBH). We conducted the deep observations using the Australia Telescope Compact Array (ATCA), spanning frequencies from 4.5 to 10 GHz, as well as the sensitive observations from the Karl G. Jansky Very Large Array (VLA) operating in its most extended A-configuration at S band (2--4 GHz) and C band (4--8 GHz). In the ATCA observations, the source shows a compact morphology, with only one direction marginally resolved. The higher resolution of the VLA allowed us to slightly resolve the source, fitting it well with a two-dimensional Gaussian model. The detected radio emission confirms the presence of Active Galactic Nucleus (AGN) activity, indicating either a low-power jet or AGN-driven winds/outflows. Our dual-epoch observations with ATCA and VLA, together with previous non-detection flux density upper limits, reveal radio emission variability spanning two decades. In addition, we find that POX 52 aligns well with the low-mass extension of the fundamental plane for high-accretion, radio-quiet massive AGNs.

astro-ph.GA↗

arXiv2024

Spectral Energy Distribution Variability of the Blazar OJ 287 during 2009-2021

Using nearly simultaneous radio, near-infrared, optical, and ultraviolet data collected since 2009, we constructed 106 spectral energy distributions (SEDs) of the blazar OJ 287. These SEDs were well-fitted by a log-parabolic model. By classifying the data into `flare' and `quiescent' segments, we found that the median flux at peak frequency of the SEDs during flare segments was 0.37$\pm$0.22 dex higher compared to quiescent segments, while no significant differences were observed in the median values of the curvature parameter $b$ or the peak frequency $\log ν_{\mathrm{p}}$. A significant bluer-when-brighter trend was confirmed through a relation between $V$ magnitude and $B-V$ color index, with this trend being stronger in the flare segments. Additionally, a significant anti-correlation was detected between $\log ν_{\mathrm{p}}$ and $b$, with a slope of 5.79 in the relation between $1/b$ and $\log ν_{\mathrm{p}}$, closer to the prediction from a statistical acceleration model other than a stochastic acceleration interpretation, though a notable discrepancy persists. This discrepancy indicates that additional factors, such as deviations from idealized conditions or radiative contributions-such as thermal emission from the accretion disk in the optical-UV range during quiescent states-may play a role in producing the observed steeper slope. Within the framework of statistical acceleration mechanism, lack of correlation between change in peak intensity and change in peak frequency suggests that change in electron energy distribution is unlikely to be responsible for the time-dependent SED changes. Instead, changes in Doppler boosting or magnetic fields may have a greater influence.

astro-ph.HE↗

arXiv2024

Multiband Optical Variability of the Blazar 3C 454.3 on Diverse Timescales

Due to its peculiar and highly variable nature, the blazar 3C 454.3 has been extensively monitored by the WEBT team. Here, we present for the first time these long-term optical flux and color variability results using data acquired in B, V, R, and I bands over a time span of $\sim$ 2 decades. We include data from WEBT collaborators and public archives such as SMARTS, Steward Observatory, and ZTF. The data are binned and segmented to study the source over this long term when more regular sampling was available. During our study, the long-term spectral variability reveals a redder when brighter (RWB) trend, which, however, stabilizes at a particular brightness cutoff $\sim$ 14.5 mag in the I-band, after which it saturates and evolves into a complex state. This trend indicates increasing jet emission dominance over accretion disk emission until jet emission completely dominates. Plots of the spectral index variation (following $F_ν \propto ν^{-α}$) reveal a bimodal distribution using a one-day binning. These correlate with two extreme phases of 3C 454.3, an outburst or high flux state and quiescent or low flux state, which are respectively jet and accretion disk dominated. We have also conducted intra-day variability studies of nine light curves and found that six of them are variable. Discrete Correlation Function (DCF) analysis between different optical waveband pairs peak at zero lags, indicating co-spatial emission in different optical bands.

astro-ph.HE↗

arXiv2024

Optical Continuum Reverberation Mapping of a Candidate IMBH in a Nearby Seyfert 1 Galaxy

To investigate the short-term variability and determine the size of the optical continuum emitting region of intermediate-mass black holes (IMBHs), we carried out high-cadence, multiband photometric monitoring of a Seyfert 1 galaxy J0249-0815 across two nights, together with a one-night single-band preliminary test. The presence of the broad Ha component in our target was confirmed by recent Paloma spectroscopic observations, 23 years after the Sloan Digital Sky Survey, ruling out the supernovae origin of the broad Ha line. The photometric experiment was primarily conducted utilizing four-channel imagers MuSCAT 3 and 4 mounted on 2 m telescopes within the Las Cumbres Observatory Global Telescope Network. Despite the expectation of variability, we observed no significant variation (<1.4%) on timescales of 6 to 10 hr. This nondetection is likely due to substantial host galaxy light diluting the subtle active galactic nucleus (AGN) variability. Additionally, we cannot rule out that the target was in a relatively quiescent state without intranight variability during our monitoring, owing to the stochastic nature of AGN variations. To enhance the possibility of detecting subtle variability signals and lag in future IMBH reverberation campaigns, it may be beneficial to select targets with a higher AGN-to-host flux ratio, and conduct dual-band preliminary tests and tailored simulations.

astro-ph.GA↗

arXiv2024

Do all the quasars and high-excitation radio galaxies (HERGs) in the 3CRR catalog contain a magnetically arrested disk (MAD)?

Based on the magnetization, an accretion disk with large-scale magnetic field can be separated into either standard and normal evolution (SANE) or magnetically arrested disk (MAD), which are difficult to identify from observations. It is still unclear whether all the radio-loud active galactic nuclei (RLAGNs) with a thin disk and strong radio emissions contain a MAD. We investigate this issue by utilizing the 3CRR catalog. We compile a sample of 35 quasars and 14 high-excitation radio galaxies powered by a thin accretion disk. In order to consistently compare with the MAD sample given by Li et al. (2022), the optical-UV emissions of our sample are all detected by the Hubble Space Telescope (HST). It is found that the average X-ray luminosity ($L_{\rm X}$) of our sample is about 5.0 times higher than that of radio-quiet AGNs (RQAGNs) with matching optical-UV luminosity ($L_{\rm UV}$), in general accord with the factor of 4.5 times in MAD sample within the uncertainty. The relationship between radio (5~GHz) and X-ray (2 keV) luminosities in the 3CRR sources is also found to be consistent with the MAD sample. Furthermore, the jet efficiencies of 3CRR sources are consistent with those from the GRMHD simulations of MAD. Therefore, we suggest that probably all the quasars and at least a fraction of high-excitation radio galaxies in the 3CRR catalog, and perhaps all the RLAGNs with strong radio emissions contain a MAD.

astro-ph.GA↗