220 citations · 1.5k across the 63 of their papers we have counts for
64 papers
A comparative analysis of the long-term optical variability characteristics of narrow and broad-line Seyfert 1 galaxies at z > 0.8
Aratrika Dey, Stalin C. S., Akshith S. +1
We present the results on a comparative analysis of the long-term optical variability characteristics of high-redshift narrow-line Seyfert 1 (NLSy1) galaxies and broad-line Seyfert…
The emergence of X-ray emission lines during relativistic radio-jet formation in the changing-look active galactic nucleus 1ES 1927+654
Dev R. Sadaula, Sibasish Laha, Eileen T. Meyer +27
We present results from a comprehensive multi-wavelength monitoring campaign of the changing-look active galactic nucleus 1ES 1927+654 during the onset and evolution of a relativis…
Narrow-Line Seyfert 1 Galaxies in the Dark Energy Spectroscopic Instrument Data Release 1
Vaidehi S. Paliya, Suvendu Rakshit, Alberto Dominguez +2
Narrow-line Seyfert 1 (NLSy1) galaxies are peculiar active galactic nuclei (AGN) known to exhibit a variety of intriguing observational features from low-frequency radio waves to h…
The Quasar Main Sequence of Super-Eddington NLSy1 Galaxies
Alberto Domínguez, Suvendu Rakshit, Vaidehi S. Paliya +2
The quasar main sequence, or Eigenvector 1 (EV1), describes the optical diversity of active galactic nuclei (AGN), with Narrow-Line Seyfert 1 (NLSy1) galaxies anchoring the high-ac…
Anomalous narrow line Seyfert I galaxies from SDSS DR17
Arihant Tiwari, Rachana, Vivek M +1
We present an analysis of 22,656 narrow-line Seyfert 1 galaxies (NLSy1s) from Sloan Digital Sky Survey (SDSS) DR17 (), identifying a sample of spectroscopically…
Spectroscopic Reverberation Mapping for SARM: The Case of Mrk 1048 and Mrk 618
Shivangi Pandey, Suvendu Rakshit, S. Muneer +14
Robust extragalactic distance measurements are crucial for resolving the persistent discrepancy in the value of the Hubble constant (H)). Active Galactic Nuclei (AGNs), through…
Probing dust torus radius--luminosity relation: An WISE view
Ashutosh Tomar, Suvendu Rakshit, Amit Kumar Mandal +1
We present measurements of the dusty torus sizes of 51 active galactic nuclei (AGNs) with a redshift of 0.8. Our analysis utilizes about 16 years of optical photometric data o…
Seoul National University AGN Monitoring Project. V. Velocity-resolved H-beta Reverberation Mapping and Evidence of Kinematics Evolution
Shu Wang, Jong-Hak Woo, Aaron J. Barth +13
We present velocity-resolved reverberation lags of H-beta for 20 active galactic nuclei (AGNs) from the Seoul National University AGN Monitoring Project. We detect unambiguous velo…
Study of mass outflows from magnetized accretion disks around rotating black holes with thermal conduction
Camelia Jana, Monu Singh, Suvendu Rakshit +1
We examine mass outflows from a low-angular momentum, viscous, advective, and magnetized accretion disk around a rotating black hole in presence of thermal conduction. We consider…
Multi-wavelength observations of a jet launch in real time from the post-changing-look Active Galaxy 1ES 1927+654
Sibasish Laha, Eileen T. Meyer, Dev R. Sadaula +34
We present results from a high cadence multi-wavelength observational campaign of the enigmatic changing look AGN 1ES 1927+654 from May 2022- April 2024, coincident with an unprece…
Spectrophotometric reverberation mapping of Intermediate-mass black hole NGC 4395
Shivangi Pandey, Suvendu Rakshit, Krishan Chand +8
Understanding the origins of massive black hole seeds and their co-evolution with their host galaxy requires studying intermediate-mass black holes (IMBHs) and estimating their mas…
Spectro-polarimetric view of the gamma-ray emitting NLS1 1H0323+342
Jincen Jose, Suvendu Rakshit, Swayamtrupta Panda +4
The gamma-ray emitting narrow-line Seyfert 1 galaxies are a unique class of objects that launch powerful jets from relatively lower-mass black hole systems compared to the Blazars.…
Testing particle acceleration in blazar jets with continuous high-cadence optical polarization observations
Ioannis Liodakis, Sebastian Kiehlmann, Alan P. Marscher +44
Variability can be the pathway to understanding the physical processes in astrophysical jets, however, the high-cadence observations required to test particle acceleration models a…
A comparative analysis of the active galactic nucleus and star formation characteristics of broad and narrow line Seyfert 1 galaxies
Kshama S. Kurian, C. S. Stalin, S. Rakshit +4
We report here our comparative analysis of active galactic nucleus (AGN) and star formation (SF) characteristics of a sample of narrow-line Seyfert 1 (NLS1) and broad-line Seyfert…
Revisiting the dust torus size-luminosity relation based on a uniform reverberation mapping analysis
Amit Kumar Mandal, Jong-Hak Woo, Shu Wang +4
We investigate the torus size -- luminosity relation of Type 1 AGNs based on the reverberation-mapping analysis using the light curves of the optical continuum and the IR continuum…
A Case for a Binary Black Hole System Revealed via Quasi-Periodic Outflows
Dheeraj R. Pasham, Francesco Tombesi, Petra Sukova +33
Binaries containing a compact object orbiting a supermassive black hole are thought to be precursors of gravitational wave events, but their identification has been extremely chall…
The Seoul National University AGN Monitoring Project III: H lag measurements of 32 luminous AGNs and the high-luminosity end of the size--luminosity relation
Jong-Hak Woo, Shu Wang, Suvendu Rakshit +28
We present the main results from a long-term reverberation mapping campaign carried out for the Seoul National University Active Galactic Nuclei (AGN) Monitoring Project. High-qual…
A re-emerging bright soft-X-ray state of the changing-look Active Galactic Nucleus 1ES~1927+654: a multi-wavelength view
Ritesh Ghosh, Sibasish Laha, Eileen Meyer +24
1ES1927+654 is a nearby active galactic nucleus that has shown an enigmatic outburst in optical/UV followed by X-rays, exhibiting strange variability patterns at timescales of mont…
The Seoul National University AGN Monitoring Project IV: H reverberation mapping of 6 AGNs and the H Size-Luminosity Relation
Hojin Cho, Jong-Hak Woo, Shu Wang +29
The broad line region (BLR) size-luminosity relation has paramount importance for estimating the mass of black holes in active galactic nuclei (AGNs). Traditionally, the size of th…
Investigating the Correlation of Outflow Kinematics with Radio Activity. Gas Outflows in AGNs. VII
Ashraf Ayubinia, Jong-Hak Woo, Suvendu Rakshit +1
We explore the relationship between the ionized gas outflows and radio activity using a sample of 6000 AGNs at z < 0.4 with the kinematical measurement based on the [O III]…
An empirical relation to estimate host galaxy stellar light from AGN spectra
Priyanka Jalan, Suvendu Rakshit, Jong-Hak Woo +2
Measurement of black hole mass for low- () Active Galactic Nuclei (AGNs) is difficult due to the strong contribution from host galaxy stellar light necessitating deta…
The first look at Narrow-Line Seyfert 1 Galaxies with eROSITA
G. Grünwald, Th. Boller, S. Rakshit +6
We present the first look at the spectral and timing analysis of Narrow-Line Seyfert 1 Galaxies (NLS1s) with the extended ROentgen Survey with an Imaging Telescope Array (eROSITA)…
Spectroscopic reverberation mapping of Quasar PKS 0736+017: Broad-Line Region and Black-hole Mass
Shivangi Pandey, Suvendu Rakshit, Jong-Hak Woo +1
To understand the mass distribution and co-evolution of supermassive black holes with their host galaxy, it is crucial to measure the black hole mass of AGN. Reverberation mapping…
On the origin of core radio emissions from black hole sources in the realm of relativistic shocked accretion flow
Santabrata Das, Anuj Nandi, C. S. Stalin +5
We study the relativistic, inviscid, advective accretion flow around the black holes and investigate a key feature of the accretion flow, namely the shock waves. We observe that th…