A Comprehensive Study of 2 000 Narrow Line Seyfert 1 Galaxies from the Sloan Digital Sky Survey: I. The Sample

Abstract

This is the first paper in a series dedicated to the study of the emission-line and continuum properties of narrow line Seyfert 1 galaxies (NLS1s). We carried out a systematic search for NLS1s from objects assigned as ``QSOs'' or ``galaxies'' in the spectroscopic sample of the Sloan Digital Sky Survey Data Release 3 (SDSS DR3) by a careful modeling of their emission lines and continua. The result is a uniform sample comprising $\sim 2000$ NLS1. This sample dramatically increases the number of known NLS1 by a factor of $\sim 10$ over previous compilations. This paper presents the parameters of the prominent emission lines and continua, which were measured accurately with typical uncertainties $<10$. Taking advantage of such an unprecedented large and uniform sample with accurately measured spectral parameters, we carried out various statistical analysis, some of which were only possible for the first time (abbreviated).

30 figures available in "jpg" format, accepted for publication in the Astrophysical Journal Supplements

References in corpus (53)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Stellar population synthesis at the resolution of 2003
• The Sloan Digital Sky Survey: Technical Summary
• A Fundamental Relation Between Supermassive Black Holes and Their Host Galaxies
• The Demography of Massive Dark Objects in Galaxy Centres
• A Relationship Between Nuclear Black Hole Mass and Galaxy Velocity Dispersion
• Theoretical Modeling of Starburst Galaxies
• The slope of the black-hole mass versus velocity dispersion correlation
• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Main Galaxy Sample
• Composite Quasar Spectra From the Sloan Digital Sky Survey
• On the Black Hole Mass - Bulge Mass Relation
• Spectroscopic Target Selection for the Sloan Digital Sky Survey: The Luminous Red Galaxy Sample
• Spectroscopic Target Selection in the Sloan Digital Sky Survey: The Quasar Sample
• The Third Data Release of the Sloan Digital Sky Survey
• The Soft X-Ray Properties of a Complete Sample of Optically Selected Quasars II. Final Results
• A Search for "Dwarf" Seyfert Nuclei. IV. Nuclei with Broad H-alpha Emission
• Measuring the black hole masses of high redshift quasars
• Candidate Type II Quasars from the Sloan Digital Sky Survey: I. Selection and Optical Properties of a Sample at 0.3<Z<0.83
• A Comprehensive Spectral and Variability Study of Narrow-Line Seyfert 1 Galaxies Observed by ASCA: II. Spectral Analysis and Correlations
• Eigenvector 1: An Optimal Correlation Space for Active Galactic Nuclei
• Narrow Line Seyfert 1 Galaxies and the Evolution of Galaxies & Active Galaxies
• The unusual emission line spectrum of IZw1
• A Comparison of Stellar and Gaseous Kinematics in the Nuclei of Active Galaxies
• A spectrophotometric atlas of Narrow-Line Seyfert 1 galaxies
• M-BH - sigma relation for a Complete Sample of Soft X-ray Selected AGNs
• A Complete Sample of Soft X-ray Selected AGN: II. Statistical Analysis
• Searching for the Physical Drivers of the Eigenvector 1 Correlation Space
• Blueshifted [O III] Emission: Indications of a Dynamic NLR
• Black Holes and Hosts of Active and Quiescent Galaxies: I. The Black Hole-Bulge Relation revisited
• The Relationship Between Black Hole Mass and Velocity Dispersion in Seyfert 1 Galaxies
• Evolution of Active Galaxies: Black-hole Mass - Bulge relations for Narrow Line Objects
• Kinematic Linkage Between the Broad and Narrow Line Emitting Gas in AGN
• FeII/MgII Emission Line Ratio in High Redshift Quasars
• Black hole mass and velocity dispersion of narrow line region in active galactic nuclei and narrow line Seyfert 1 galaxies
• Polar Outflows in Six Broad Absorption Line Quasars
• Obscured Binary Quasar Cores in SDSS J104807.74+005543.5?
• Narrow-line Seyfert 1 Galaxies from the Sloan Digital Sky Survey Early Data Release
• Exploring NLS1 through the physical properties of their hosts
• Ensemble Learning Independent Component Analysis of Normal Galaxy Spectra
• A Statistical Study of Rest-frame Optical Emission Properties in Luminous Quasars at 2.0 < z < 2.5
• Partially obscured quasars in the Sloan Digital Sky Survey Early Data Release
• Black hole masses in narrow-line Seyfert 1 galaxies
• Spectroscopic Properties of QSOs Selected from Ultraluminous Infrared Galaxy Samples
• The Continuum Slopes of Optically Selected QSOs
• Radio Loud AGN in the Context of the Eigenvector 1 Parameter Space
• Implications of Quasar Black Hole Masses at High Redshifts
• Observational Similarities and Potential Connections Between Luminous Ultrasoft NLS1s and BALQSOs
• The Narrow Line Region of Narrow-Line Seyfert 1 Galaxies
• An AGN Sample with High X-ray-to-optical Flux Ratio from RASS II.Optical Emission Line Properties of Seyfert 1 Type AGN
• ROSAT Soft X-Ray Properties of the Large Bright Quasar Survey: Modeling of Stacked X-Ray Spectra
• Hybrid nature of 0846+51W1: a BL Lac object with a narrow line Seyfert 1 nucleus
• ASCA Observations of NLS1s

Cited by in corpus (239)

• Galaxy Zoo Green Peas: Discovery of A Class of Compact Extremely Star-Forming Galaxies
• Radio-Loud Narrow-Line Seyfert 1 as a New Class of Gamma-Ray AGN
• A Population of Radio-loud Narrow Line Seyfert 1 Galaxies with Blazar-like Properties?
• The Simultaneous Optical-to-X-ray Spectral Energy Distribution of Soft X-ray Selected AGN observed by Swift
• The effect of radiation pressure on virial black hole mass estimates and the case of Narrow Line Seyfert 1 galaxies
• The black hole mass - stellar velocity dispersion relation of narrow-line Seyfert 1 galaxies
• Science with e-ASTROGAM (A space mission for MeV-GeV gamma-ray astrophysics)
• The Fermi blazars divide
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$\beta$ Time Lags and Implications for Super-Eddington Accretion
• Fermi/LAT discovery of gamma-ray emission from a relativistic jet in the narrow-line quasar PMN J0948+0022
• Broad-line Balmer Decrements in Blue Active Galactic Nuclei
• On the nature of Seyfert galaxies with high [OIII]5007 blueshifts
• A Combined Optical and X-ray Study of Unobscured Type 1 AGN. I. Optical Spectra and SED Modeling
• Type 2 AGNs with Double-Peaked [O III] Lines: Narrow Line Region Kinematics or Merging Supermassive Black Hole Pairs?
• Black hole mass estimate for a sample of radio-loud narrow-line Seyfert 1 galaxies
• Properties of flat-spectrum radio-loud Narrow-Line Seyfert 1 Galaxies
• A combined Optical and X-ray Spectra Study for Type 1 AGN. III. Broadband SED Properties
• A Catalog of Narrow Line Seyfert 1 Galaxies from the Sloan Digital Sky Survey Data Release 12
• Enhanced Star Formation in Narrow Line Seyfert 1 AGN revealed by Spitzer
• Detailed Characterization of H_beta emission line profile in low z SDSS quasars
• A narrow line Seyfert 1--blazar composite nucleus in 2MASX J0324+3410
• Are the black hole masses in Narrow Line Seyfert 1 galaxies actually small?
• SBS 0846+513: a new gamma-ray emitting Narrow-Line Seyfert 1 galaxy
• Narrow-line Seyfert 1 Galaxies and the M_BH - sigma Relation
• Self-shadowing Effects of Slim Accretion Disks in Active Galactic Nuclei: Diverse Appearance of the Broad-line Region
• A Uniformly Selected Sample of Low-mass Black Holes in Seyfert 1 Galaxies
• The Role of Secular Evolution in the Black Hole Growth of Narrow-Line Seyfert 1 Galaxies
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. III. Detection of Fe II Reverberation in Nine Narrow-Line Seyfert 1 Galaxies
• Super-Eddington accreting massive black holes as long-lived cosmological standards
• A spectroscopic analysis of a sample of narrow-line Seyfert 1 galaxies selected from the Sloan Digital Sky Survey
• VLT/ISAAC Spectra of the Hbeta Region in Intermediate-Redshift Quasars III. Hbeta Broad Line Profile Analysis and Inferences about BLR Structure
• New Insights on the QSO Radio-Loud/Radio-Quiet Dichotomy: SDSS Spectra in the Context of the 4D Eigenvector1 Parameter Space
• Kiloparsec-scale Radio Structures in Narrow-line Seyfert 1 Galaxies
• Dependence of the optical/UV variability on the emission line properties and Eddington ratio in active galactic nuclei
• The Discovery and Nature of Optical Transient CSS100217:102913+404220
• Spitzer Mid-Infrared Spectroscopy of Infrared Luminous Galaxies at z~2 III: Far-IR to Radio Properties and Optical Spectral Diagnostics
• Correlation Analysis of a Large Sample of Narrow-Line Seyfert 1 Galaxies: Linking Central Engine and Host Properties
• A comprehensive and uniform sample of broad-line active galactic nuclei from the SDSS DR7
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. VIII. Structure of the Broad-Line Region and Mass of the Central Black Hole in Mrk 142
• Radio jet emission from GeV-emitting narrow-line Seyfert 1 galaxies
• NTT, Spitzer and Chandra spectroscopy of SDSSJ095209.56+214313.3: the most luminous coronal-line supernova ever observed, or a stellar tidal disruption event ?
• Is Mg II 2800 a Reliable Virial Broadening Estimator for Quasars?
• Broad Line Emission in Low-Metallicity Blue Compact Dwarf Galaxies: Evidence for Stellar Wind, Supernova and Possible AGN Activity
• The first gamma-ray outburst of a Narrow-Line Seyfert 1 Galaxy: the case of PMN J0948+0022 in July 2010
• The Peculiar Radio-Loud Narrow Line Seyfert 1 Galaxy 1H 0323+342
• What controls the Fe II strength in active galactic nuclei?
• Radio-loud Narrow Line Seyfert 1 under a different perspective: a revised black hole mass estimate from optical spectropolarimetry
• A Combined Optical and X-ray Study of Unobscured Type 1 AGN. II. Relation Between X-ray Emission and Optical Spectra
• A Family Tree of Optical Transients from Narrow-Line Seyfert 1 Galaxies
• The [OIII] emission line luminosity function of optically selected type-2 AGN from zCOSMOS
• Origin and Dynamical Support of Ionized Gas in Galaxy Bulges
• Elusive AGN in the XMM-Newton bright serendipitous survey
• Rapid Infrared Variability of Three Radio-loud Narrow-line Seyfert 1 Galaxies: A View from the Wide-field Infrared Survey Explorer
• Parent population of flat-spectrum radio-loud narrow-line Seyfert 1 galaxies
• The Radio Properties of Radio-Loud Narrow-Line Seyfert 1 Galaxies on Parsec Scales
• Low-z MgII Broad Absorption-Line Quasars from the Sloan Digital Sky Survey
• A Tidal Flare Candidate in Abell 1795
• Optical Variability of Narrow and Broad line Seyfert 1 galaxies
• The NuSTAR Serendipitous Survey: The 40 month Catalog and the Properties of the Distant High Energy X-ray Source Population
• Radio jets and gamma-ray emission in radio-silent narrow-line Seyfert 1 galaxies
• The host-galaxy of the gamma-ray Narrow-line Seyfert 1 galaxy 1H~0323+342
• Gamma-ray Emitting Narrow Line Seyfert 1 Galaxies in The Sloan Digital Sky Survey
• A new cosmological distance measure using AGN X-ray variability
• X-Ray Properties of Narrow-Line Seyfert 1 Galaxies with Very Small Broad-Line Widths
• Very Long Baseline Array Imaging of Parsec-scale Radio Emissions in Nearby Radio-quiet Narrow-line Seyfert 1 Galaxies
• Narrow Line Seyfert 1 galaxies at hard X-rays
• Identification of a New $\gamma$-ray-emitting narrow-line Seyfert 1 Galaxy, at Redshift $\sim 1$
• Compact steep-spectrum sources as the parent population of flat-spectrum radio-loud NLS1s
• Stellar Photometric Structures of the Host Galaxies of Nearby Type 1 Active Galactic Nuclei
• NLS1 galaxies and estimation of their central black hole masses from the X-ray excess variance method
• Multifrequency studies of the narrow-line Seyfert 1 galaxy SBS 0846+513
• Very Long Baseline Array Imaging of Parsec-scale Jet Structures in Radio-loud Narrow-line Seyfert 1 Galaxies
• SDSS J160531.84+174826.1: A Dwarf Disk Galaxy With An Intermediate-Mass Black Hole
• Constraints on the Broad Line Region Properties and Extinction in Local Seyferts
• Kiloparsec-scale jets in three radio-loud narrow-line Seyfert 1 galaxies
• AGN with strong forbidden high-ionisation lines selected from the Sloan Digital Sky Survey
• Low-Ionization Outflows in High Eddington Ratio Quasars
• Time delay measurement of Mg II line in CTS C30.10 with SALT
• High metal content of highly accreting quasars
• The M_bh-sigma diagram, and the offset nature of barred active galaxies
• A Tidal Disruption Event in a Nearby Galaxy Hosting an Intermediate Mass Black Hole
• Investigating kpc-scale radio emission properties of narrow-line Seyfert 1 galaxies
• Evidence for an intermediate line region in AGN's inner torus region and its evolution from narrow to broad line Seyfert I galaxies
• SDSSJ143244.91+301435.3: a link between radio-loud narrow-line Seyfert 1 galaxies and compact steep-spectrum radio sources?
• The compact radio structure of radio-loud narrow line Seyfert 1 galaxies
• Probing narrow-line Seyfert 1 galaxies in the southern hemisphere
• The narrow-line region of narrow-line and broad-line type 1 AGN I. A zone of avoidance in density
• Extinction curve template for intrinsically reddened quasars
• The Baldwin effect in the narrow emission lines of AGNs
• Investigation on Young radio AGNs based on SDSS spectroscopy
• Blazar nuclei in radio-loud narrow-line Seyfert 1?
• A Uniformly Selected Sample of Low-Mass Black Holes in Seyfert 1 Galaxies. II. The SDSS DR7 Sample
• SDSS1133: An Unusually Persistent Transient in a Nearby Dwarf Galaxy
• Jet Properties of GeV-Selected Radio-Loud Narrow-Line Seyfert 1 Galaxies and Possible Connection to Their Disk and Corona
• Large-scale environments of narrow-line Seyfert 1 galaxies
• GTC Spectra of z ~ 2.3 Quasars: Comparison with Local Luminosity Analogues
• The Gamma-Ray Emitting Radio-Loud Narrow-Line Seyfert 1 Galaxy PKS 2004-447 II. The Radio View
• A comparative study of optical/ultraviolet variability of narrow-line Seyfert 1 and broad-line Seyfert 1 active galactic nuclei
• The Nature of gamma-ray Loud Narrow Line Seyfert I Galaxies PKS 1502+036 and PKS 2004-447
• A comparison of hard X-ray photon indices and iron \ka emission lines in X-ray luminous narrow- and broad-line Seyfert 1 galaxies
• Statistical multifrequency study of narrow-line Seyfert 1 galaxies
• Broadband Observations of High Redshift Blazars
• A Tidal Disruption Event Candidate Discovered in the Active Galactic Nucleus SDSS J022700.77-042020.6
• Anomalously Steep Reddening Law in Quasars: An Exceptional Example Observed in IRAS14026+4341
• Short-Term Radio Variability and Parsec-Scale Structure in a Gamma-Ray Narrow-Line Seyfert 1 Galaxy 1H 0323+342
• SDSS J211852.96-073227.5: a new γ-ray flaring narrow-line Seyfert 1 galaxy
• Modelling narrow-line regions of active galaxies in the Sloan Digital Sky Survey - I.Sample selection and physical conditions
• Absence of the predicted 2022 October outburst of OJ 287 and implications for binary SMBH scenarios
• The rise and fall of the iron-strong nuclear transient PS16dtm
• Dust reddening in star-forming galaxies
• Two New "Turn-off" Changing-look Active Galactic nuclei and Implication on "Partially Obscured" AGNs
• A Fanaroff-Riley Type I Candidate in Narrow-Line Seyfert 1 Galaxy Mrk 1239
• VLT/X-shooter GRBs: Individual extinction curves of star-forming regions
• Asymmetric emission of the [OIII]$\lambda$5007 profile in narrow-line Seyfert 1 galaxies
• Reddening of the BLR and NLR in AGN From a Systematic Analysis of Balmer Decrement
• Intra-night optical variability characteristics of different classes of narrow line Seyfert 1 galaxies
• Multiwavelength observations of the gamma-ray emitting narrow-line Seyfert 1 PMN J0948+0022 in 2011
• The Gamma-Ray Emitting Radio-Loud Narrow-Line Seyfert 1 Galaxy PKS 2004-447 I. The X-Ray View
• Extreme Gaseous Outflows in Radio-Loud Narrow-Line Seyfert 1 Galaxies
• Superluminous transients at AGN centers from interaction between black-hole disk winds and broad-line region clouds
• Inner jet kinematics and the viewing angle towards the γ-ray narrow-line Seyfert 1 galaxy 1H 0323+342
• Chandra and MMT observations of low-mass black hole active galactic nuclei accreting at low rates in dwarf galaxies
• A Quasar Catalog with Simultaneous UV, Optical and X-ray Observations by Swift
• Detection of a Parsec-Scale Jet in a Radio-Quiet Narrow-Line Seyfert 1 Galaxy with Highly Accreting Supermassive Black Hole
• Modeling accretion disk emission with generalized temperature profile and its effect on AGN spectral energy distribution
• A new method to measure the virial factors in the reverberation mapping of AGNs
• Empirical Links between XRB and AGN accretion using the complete z<0.4 spectroscopic CSC/SDSS Catalog
• Exploring the Spectral Space of Low Redshift QSOs
• Fermi Monitoring of Radio-loud Narrow Line Seyfert 1 Galaxies
• X-ray/UV variability and the origin of soft X-ray excess emission from II Zw 177
• Panchromatic Properties of the Extreme FeII Emitter PHL 1092
• Difference in Narrow Emission Line Spectra of Seyfert 1 and 2 galaxies
• Rare finding of a 100 kpc large double-lobed radio galaxy hosted in the Narrow Line Seyfert 1 galaxy SDSS J103024.95+551622.7
• A Study of Outflows in Luminous Quasars at Redshift $\sim 0.4-0.8$
• Comparing Hbeta Line Profiles in the 4D Eigenvector 1 Context
• Possible ~0.4 hour X-ray quasi-periodicity from an ultrasoft active galactic nucleus
• The intrinsic Baldwin effect in broad Balmer lines of six long-term monitored AGNs
• Is IRAS 01072+4954 a True-Seyfert 2? Hints from Near Infrared Integral Field Spectroscopy
• The radio structure of 3C 316, a galaxy with double-peaked narrow optical emission lines
• A Radio Quasi-periodic Oscillation of 176 day in the Radio-loud Narrow-line Seyfert 1 Galaxy J0849+5108
• Intra-Night Optical monitoring of three γ-ray detected Narrow-line Seyfert 1 galaxies
• SDSS J094635.06+101706.1: a redshift one, very radio-loud, γ-ray emitting narrow-line Seyfert 1 galaxy
• Do the spectral energy distributions of type 1 AGN show diversity?
• Unshifted Metastable He I* Mini-Broad Absorption Line System in the Narrow Line Type 1 Quasar SDSS J080248.18$+$551328.9
• On the nature of the red, 2MASS selected AGN in the local Universe I: an optical spectroscopic study
• Broad reprocessed Balmer emission from warped accretion discs
• A comparison of X-ray photon indices among the narrow and broad-line Seyfert 1 galaxies
• Relativistic Fe K$\alpha$ Line Revealed in the Composite X-ray Spectrum of Narrow Line Seyfert 1 Galaxies --- do their black holes have averagely low or intermediate spins?
• Spectroscopic classification, variability and SED of the Fermi-detected CSS 3C 286: the radio-loudest NLS1 galaxy?
• Probing Spectroscopic Variability of Galaxies & Narrow-Line Active Galactic Nuclei in the Sloan Digital Sky Survey
• Gamma-ray Emitting Narrow-Line Seyfert 1 Galaxies: Past, Present, and Future
• Spectral nuclear properties of NLS1 galaxies
• The Extreme Super-Eddington NLS1 RX J0134.2-4258 -- II. A Weak-Line Seyfert Linking to the Weak-Line Quasar
• Are Narrow Line Seyfert 1 Galaxies powered by low mass black holes?
• Multiwavelength Study of an X-ray Tidal Disruption Event Candidate in NGC 5092
• A note on black hole masses estimated by the second moment in Narrow Line Seyfert 1 Galaxies
• The X-ray luminous galaxies optically classified as star forming are mostly narrow line Seyfert 1s
• Discovery of Dramatic Optical Variability in SDSS J1100+4421: A Peculiar Radio-Loud Narrow-Line Seyfert 1 Galaxy?
• Active Galactic Nuclei with Double-Peaked Balmer Lines: I. Black Hole Masses and the Eddington ratios
• Interpreting automatic AGN classifiers with saliency maps
• SDSS J163459.82+204936.0: A Ringed Infrared-Luminous Quasar with Outflows in both Absorption and Emission Lines
• A Radio Detection Survey of Narrow-Line Seyfert 1 Galaxies using Very-Long-Baseline Interferometry at 22 GHz
• The Close AGN Reference Survey (CARS): Tracing the circumnuclear star formation in the super-Eddington NLS1 Mrk 1044
• Comparative intra-night optical variability of X-ray and $\gamma$-ray detected narrow-line Seyfert 1 galaxies
• Independent Black Hole Mass Estimation for the γ-ray Detected Archetypal Narrow-Line Seyfert 1 Galaxy 1H 0323+342 from X-ray Variability
• FBQS J1644+2619: multiwavelength properties and its place in the class of gamma-ray emitting Narrow Line Seyfert 1s
• Early Science Result from the Japanese Virtual Observatory: AGN and Galaxy Clustering at z = 0.3 to 3.0
• TXS 1206+549: a new $\gamma$-ray detected narrow-line Seyfert 1 galaxy at redshift 1.34?
• Mrk 1239: a Type-2 Counterpart of Narrow-line Seyfert-1?
• Broad-band spectral energy distribution of 3000 Angstroem break quasars from the Sloan Digital Sky Survey
• Radio jet structures at ~100 parsec and larger scales of the $\gamma$-ray-emitting narrow-line Seyfert 1 galaxy PMN J0948+0022
• An Unobscured type II quasar candidate: SDSS J012032.19-005501.9
• Reddening and He I* $\lambda 10830$ Absorption Lines in Three Narrow-line Seyfert 1 Galaxies
• Properties of the narrow line Seyfert 1 galaxies revisited
• The radio structure of the peculiar narrow-line Seyfert 1 galaxy candidate J1100+4421
• Line shapes in narrow-line Seyfert 1 galaxies: a tracer of physical properties?
• The SOUX AGN Sample: SDSS-XMM-Newton Optical, Ultraviolet and X-ray selected active galactic nuclei spanning a wide range of parameter space -- Sample definition
• Observations of the gamma-ray emitting narrow-line Seyfert 1, SBS 0846+513, and its host galaxy
• The relativistic jet of the $\gamma$-ray emitting narrow-line Seyfert 1 galaxy PKS J1222$+$0413
• Quasars as standard candles VI: spectroscopic validation of the cosmological sample
• Optical polarisation variability of radio loud narrow line Seyfert 1 galaxies. Search for long rotations of the polarisation plane
• The radio-loud narrow-line Seyfert 1 galaxy 1H 0323+342 in a galaxy merger
• X-ray Absorption and Optical Extinction in the Partially Obscured Seyfert Nucleus in Mrk 1393
• High-redshift Narrow-line Seyfert 1 Galaxies: A Candidate Sample
• A Deeply Buried Narrow-Line Seyfert 1 Nucleus Uncovered in Scattered Light
• Radio spectra of narrow-line Seyfert 1 galaxies observed with ATCA and VLASS
• Insights Into AGN and Host Galaxy Co-evolution From Hard X-ray Emission
• Gamma-ray-emitting narrow-line Seyfert 1 galaxies: the Swift view
• B2 0954+25A: a typical Fermi blazar or a gamma-loud Narrow Line Seyfert 1
• Line and Continuum Variability in Active Galaxies
• Type 1 Active Galactic Nucleus Fraction in SDSS/FIRST Survey
• Dependence of the broad Fe K$\alpha$ line on the physical parameters of AGN
• Role of Feedback in AGN-HOST Coevolution: A Study from Partially Obscured Active Galactic Nuclei
• Searching for Kardashev Type III civilisations from High $q$-Value Sources in the LoTSS-DR1 Value-added Catalogue
• Accretion disc-corona and jet emission from the radio-loud narrow-line Seyfert 1 galaxy RX J1633.3+4719
• A Direct Linkage Between AGN Outflows in The Narrow-line Regions and The X-ray Emission From The Accretion disks
• A Study of Active Galactic Nuclei in Low Surface Brightness Galaxies with Sloan Digital Sky Survey Spectroscopy
• Eddington Ratios of Dust-obscured Quasars at $z\lesssim 1$: Evidence Supporting Dust-obscured Quasars as Young Quasars
• A low-luminosity type-1 QSO sample; III. Optical spectroscopic properties and activity classification
• Properties of radio-loud quasars in Sloan Digital Sky Survey
• The radio luminosity, black hole mass and Eddington ratio for quasars from the Sloan Digital Sky Survey
• Multiple giant eruptions and X-ray emission in the recoiling AGN/LBV candidate SDSS1133
• Compact radio emission from z~0.2 X-ray bright AGN
• Optical spectroscopic classification of 35 hard X-ray sources from the Swift-BAT 70-month catalogue
• Exploring the physics of the accretion and jet in nearby narrow-line Seyfert 1 galaxies
• Short time-scale variability of $\gamma$-ray-emitting narrow-line Seyfert 1 galaxies in optical and UV bands
• Narrow vs. Broad line Seyfert 1 galaxies: X-ray, optical and mid-infrared AGN characteristics
• The broad-band spectrum of the Narrow-line Seyfert 1 NGC 4748: from UV to hard X-ray
• Probing the Heart of Active Narrow-line Seyfert 1 Galaxies with VERA Wideband Polarimetry
• A comparative study of the physical properties for a representative sample of Narrow and Broad-line Seyfert galaxies
• The radio structure of the $\gamma$-ray narrow-line Seyfert 1 galaxy SDSS J211852.96$-$073227.5
• Compact and variable radio emission from an active galaxy with supersoft X-ray emission
• Spatially-resolved spectroscopy of narrow-line Seyfert 1 host galaxies
• Long-term Swift and Metsähovi monitoring of SDSS J164100.10+345452.7 reveals multi-wavelength correlated variability
• Powerful Radio Emission From Low-mass Supermassive Black Holes Favors Disk-like Bulges
• Three Spectacular HII-buried-AGN Galaxies from SDSS
• Brightness and colour variability in NLSy1s
• An optical perspective on early-stage AGN with extreme radio flares
• Characterization of the continuum and kinematical properties of nearby NLS1
• Low-mass and High-mass Supermassive Blackholes In Radio-Loud AGNs Are Spun-up in Different Evolution Paths
• Ultra-dense Broad-line Region Scale Outflow in Highly Reddened Quasar SDSS J145057.28+530007.6
• Optical identification of radio-loud active galactic nuclei in the ROSAT-Green-Bank sample with SDSS spectroscopy
• Relativistic jets in narrow-line Seyfert 1 galaxies. New discoveries and open questions
• The rare extended radio-loud narrow-line Seyfert 1 galaxy SDSS J1030+5516 at high resolution
• Estimate of SMBH Spin for Narrow-Line Seyfert 1 Galaxies
• The Parsec-scale Structure, Kinematics, and Polarization of Radio-Loud Narrow-Line Seyfert 1 Galaxies
• On the orientation of Narrow Line Seyfert I
• AGN orientation through the spectroscopic correlations and model of dusty cone shell
• Obscured Narrow-Line Seyfert 1 Galaxy Candidate Mrk 1388 with Nonthermal Jets
• The viewing angle in AGN SED models, a data-driven analysis
• Association of Optical, Ultraviolet and Soft X-ray excess Emissions in AGNs
• Radio and gamma-ray loud narrow-line Seyfert 1 galaxies in the spotlight
• Gamma-ray emitting narrow-line Seyfert 1 galaxies. New discoveries and open questions
• A comparative study of ultraluminous infrared galaxies in the IRAS and SDSS Surveys
• Discovery of an Intermediate Mass Black Hole at the center of the starburst/Seyfert composite galaxy IRAS 01072+4954
• A catalog of narrow-line Seyfert 1 galaxies in the southern hemisphere
• Where's Swimmy?: Mining unique color features buried in galaxies by deep anomaly detection using Subaru Hyper Suprime-Cam data
• Intra-night optical variability study of a non-jetted narrow-line Seyfert 1 galaxy: SDSS J163401.94+480940.1
• Evidence of jet induced optical microvariability in radio-loud Narrow Line Seyfert 1 Galaxies