A5091094415- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Adaptive optics and wavefront sensing
- Cosmology and Gravitation Theories
- Astronomical Observations and Instrumentation
- Geophysics and Gravity Measurements
- Academic Publishing and Open Access
- Black Holes and Theoretical Physics
- Gaussian Processes and Bayesian Inference
- Relativity and Gravitational Theory
- GNSS positioning and interference
Institute of High Energy Physics
2017-2024
Chinese Academy of Sciences
2017-2024
University of Chinese Academy of Sciences
2017-2024
China Spallation Neutron Source
2023-2024
Abstract In this work, we present the first results of long-term high-cadence spectroscopic monitoring 15 PG quasars with relatively strong Fe ii emission, as a part broader reverberation mapping campaign performed using Calar Alto Observatory’s 2.2 m telescope. The V -band, 5100 Å continuum, and H β broad emission line light curves are measured for set periods ranging from dozens to more than hundred epochs between 2017 May 2020 July. Accurate time lags variations broad-line fluxes optical...
In this third paper of the series reporting on reverberation mapping (RM) campaign active galactic nuclei with asymmetric H$\beta$ emission-line profiles, we present results for 15 Palomar-Green (PG) quasars using spectra obtained between end 2016 to May 2021. This combines long time spans relatively high cadence. For 8 objects, both lags from entire light curves and measurements individual observing seasons are provided. Reverberation 9 our targets has been attempted first time, while 6...
ABSTRACT We conduct a systematic search for quasars with periodic variations from the archival photometric data of Zwicky Transient Facility by cross-matching quasar catalogues Sloan Digital Sky Survey and Véron-Cetty Véron. first select out 184 primitive candidates using generalized Lomb–Scargle periodogram autocorrelation function then estimate their statistical significance periodicity based on two red-noise models, i.e. damped random walk (DRW) single power-law (SPL) models. As such, we...
Abstract We report first-time reverberation-mapping results for 14 active galactic nuclei (AGNs) from the ongoing Monitoring AGNs with H β Asymmetry campaign (MAHA). These utilize optical spectra obtained Long Slit Spectrograph on Wyoming Infrared 2.3 m Telescope between 2017 November and 2023 May. MAHA combines long-duration monitoring high cadence. multiple observing seasons nine of objects. include time lags, supermassive black hole masses, velocity-resolved lags. The lags allow us to...
We report the results of a multi-year spectroscopic and photometric monitoring campaign two luminous quasars, PG~0923+201 PG~1001+291, both located at high-luminosity end broad-line region (BLR) size-luminosity relation with optical luminosities above $10^{45}~{\rm erg~s^{-1}}$. is for first time monitored, PG~1001+291 was previously monitored but our has much longer temporal baseline. detect lags variations broad H$\beta$, H$\gamma$, Fe {\sc ii} lines respect to those 5100~{\AA} continuum....
Abstract The growing “Hubble tension” has prompted the need for precise measurements of cosmological distances. This paper demonstrates a purely geometric approach determining distances to extragalactic binaries through joint analysis spectroastrometry (SA), radial velocity (RV), and light-curve (LC) observations. A parameterized model binary system is outlined, simulated SA, RV, LC data are computed infer probability distribution parameters based on mock data. impacts quality distance...
We report on the results of a new spectroscopic monitoring campaign quasar PG 0026+129 at Calar Alto Observatory 2.2m telescope from July 2017 to February 2020. Significant variations in fluxes continuum and broad-emission lines, including H$\beta$ He II, were observed first third years, clear time lags between them are measured. The broad line profile consists two Gaussian components: an intermediate-width H$\beta_{\rm IC}$ with full width half-maximum (FWHM) 1964$\pm$18 $\rm km~s^{-1}$...
ABSTRACT We compile optical and mid-infrared light curves from the time-domain surveys (i.e. CRTS, PTF, ZTF, ASAS-SN) Wide-field Infrared Survey Explorer (WISE) archive for a selected sample of active galactic nuclei (AGNs) with Hβ reverberation mapping (RM) measurements. measure time lags (and thus torus sizes) W1 (∼3.4 $\mu$ m) W2 (∼4.6 band relative to one using MICA method. Through RM, has well-measured AGN properties, therefore allowing us reliably constrain relations between sizes...
Abstract Strong iron lines are a common feature of the optical spectra active galactic nuclei (AGNs) and quasars from z ∼ 6−7 to local universe, [Fe/Mg] ratios do not show cosmic evolution. During episodes, accretion disks surrounding supermassive black holes (SMBHs) inevitably form stars in self-gravitating part, these accrete with high rates. In this paper, we investigate population evolution accretion-modified (AMSs) produce magnesium AGNs. The AMSs, as new type star, allowed have any...
Abstract We conduct a reverberation mapping (RM) campaign to spectroscopically monitor sample of selected bright active galactic nuclei with large anticipated broad-line region (BLR) sizes adequate for spectroastrometric (SA) observations by the GRAVITY instrument on Very Large Telescope Interferometer. report first results five objects, IC 4329A, Mrk 335, 509, 1239, and PDS 456, among which 1239 456 are time monitored. obtain multiyear monitoring data perform multicomponent spectral...
Abstract Over the past three decades, multiple reverberation mapping (RM) campaigns conducted for quasar PG 2130+099 have exhibited inconsistent findings with time delays ranging from ∼10 to ∼200 days. To achieve a comprehensive understanding of geometry and dynamics broad-line region (BLR) in 2130+099, we continued an ongoing high-cadence RM monitoring campaign using Calar Alto Observatory 2.2 m optical telescope extra four years 2019 2022. We measured lags several broad emission lines...
Abstract This is the eighth in a series of papers reporting on large reverberation mapping (RM) campaign to measure black hole (BH) mass active galactic nuclei with high accretion rates. We employ recently developed dynamical modeling approach for broad-line regions (BLRs) based method Pancoast et al. analyze RM data set Mrk 142 observed first monitoring season. In this approach, continuum variations are reconstructed using damped random walk process, and BLR structure delineated flexible...
Abstract The quasar 3C 273 has been observed with infrared spectroastrometry (SA) of the broad Pa α line and optical reverberation mapping (RM) H β line. SA delivers information about angular size structure broad-line region (BLR), while RM physical BLR. Based on fact that two BLRs share mass supermassive black hole (SMBH) viewing inclination, a combination velocity-resolved (SARM) thereby allows us to simultaneously determine SMBH geometric distance through dynamically modeling BLRs. We...
Most large galaxies harbor supermassive black holes (SMBHs) in their centers, and merge. Consequently, binary SMBHs should be common galactic nuclei. However, close binaries of SMBH (CB-SMBHs) with sub-parsec separation cannot imaged directly using current facilities. Some indirect signatures, such as periodic signals light curves double peaks emission-line profile, have been used to find CB-SMBH candidates, but ambiguities still exist no definitive conclusions can made. We recently proposed...
As a major feature in spectra of active galactic nuclei, broad emission lines deliver information kinematics and spatial distributions ionized gas surrounding the central supermassive black holes (SMBHs), that is so-called broad-line regions (BLRs). There growing evidence for appearance spiral arms BLRs. It has been shown by reverberation mapping (RM) campaigns characterized radius BLRs overlaps with self-gravitating accretion disks. In framework WKB approximation, we show robust properties...
Abstract Pairs of supermassive black holes (SMBHs) at different stages are the natural results galaxy mergers in hierarchical framework formation and evolution. However, identification close binaries SMBHs (CB-SMBHs) with sub-parsec separations observations still elusive. Recently, unprecedented spatial resolutions achieved by GRAVITY/GRAVITY+ on board Very Large Telescope Interferometer through spectroastrometry (SA) provide new opportunities to resolve CB-SMBHs. Differential phase curves...
Close binaries of supermassive black holes (CB-SMBHs) with separations $\lesssim 0.1$pc as the final stage galaxy mergers are sources low frequency gravitational waves (GW), however, they still elusive observationally because not spatially resolved. Fortunately, reverberation echoes broad emission lines to ionizing continuum conveys invaluable information dynamics broad-line regions (BLRs) governed by in central active galactic nuclei (AGNs). In this paper, we demonstrate how composite...
It arises a puzzle in \NGC\, how to secularly maintain the counter-rotating disc from $0.2$ $7\,$pc unambiguously detected by recent ALMA observations of molecular gas. Upon further analysis dynamics, we find that Kelvin-Helmholtz (KH) instability (KHI) results an unavoidable catastrophe developed at interface between reversely rotating parts, and demonstrate close binary supermassive black holes provides tidal torques as unique external sources prevent KH catastrophe. We are led inescapable...
Measuring broad emission-line widths in active galactic nuclei (AGN) is not straightforward owing to the complex nature of flux variability these systems. Line-width measurements become especially challenging when signal-to-noise low, profiles are narrower, or spectral resolution low. We conducted an extensive correlation analysis between from optical spectra Markarian 142 (Mrk 142; a narrow-line Seyfert galaxy) taken with Gemini North Telescope (Gemini) at 185.6+\-10.2 km/s and Lijiang...
Black hole (BH) mass of Type I active galactic nuclei (AGN) can be measured or estimated through either reverberation mapping (RM) empirical $R-L$ relation, however, both them suffer from uncertainties the virial factor ($f_{\rm BLR}$), thus limiting measurement accuracy. In this letter, we make an effort to investigate $f_{\rm BLR}$ polarised spectra broad-line regions (BLR) arisen electrons in equatorial plane. Given BLR composed discrete clouds with Keplerian velocity around central BH,...
Abstract A few months ago, GRAVITY at the Very Large Telescope Interferometry revealed structure and kinematics of broad-line region (BLR) 3C 273. works with an unprecedented high spatial resolution through spectroastrometry where centers photons different wavelengths ( λ -photoncenters) active galactic nuclei are measured by differential phase curves (DPCs) in wavelength range broad Paschen α line. Since Doppler effects govern shifts sensitively depending on degree ordered rotation <?CDATA...
In the present paper, we explore opportunities of applying GRAVITY at Very Large Telescope Interferometry (VLTI) with unprecedented spatial resolution to identify close binaries supermassive black holes (CB-SMBHs) in active galactic nuclei (AGNs). Each SMBH is assumed be separately surrounded by their own broad-line regions (BLRs) composed clouds virialized motion. Composition binary orbital motion and virial each BLR determines projected velocity fields hence differential phase curves,...
We conduct a reverberation mapping (RM) campaign to spectroscopically monitor sample of selected bright active galactic nuclei with large anticipated broad-line region (BLR) sizes adequate for spectroastrometric observations by the GRAVITY instrument on Very Large Telescope Interferometer. report first results five objects, IC 4329A, Mrk 335, 509, 1239, and PDS 456, among which 1239 456 are time monitored. obtain multi-year monitoring data perform multi-component spectral decomposition...