activity
20092026
most citedA Comprehensive Measurement of the Local Value of the Hubble Constant with 1 km/s/Mpc Uncertainty from the Hubble Space Telescope and the SH0ES Team

2.3k citations · 6.2k across the 182 of their papers we have counts for

collaborators
Showing astro-ph.GAShow all

14 papers · 1 filter

astro-ph.GA2026

CHASE Spectral Survey I: Measuring Contamination in the Color-selected J-region Asymptotic Giant Branch Distance Indicator

Siyang Li, Alexei V. Filippenko, Arief Ahmad +11

The J-region asymptotic giant branch (JAGB) method for distance measurements uses the near uniform luminosity of carbon-rich AGB stars as a standard candle. Its application rests o…

astro-ph.GA2026

In the Eye of the Storm: The Third Giant X-ray Outburst of the Extreme Changing-look AGN IC 3599

D. Grupe, S. Komossa, W. Zheng +10

We report the discovery and multiwavelength follow-up observations of a giant (factor >100) X-ray outburst of the exceptional changing-look active galactic nucleus (AGN) IC 3599. T…

astro-ph.GA2026

OQ~208: A New Fe~II Changing-look Active Galactic Nucleus and Implications for the Nature of the Changing-look Phenomenon

J. Wang, W. K. Zheng, D. W. Xu +5

In addition to the traditional hydrogen Balmer emission lines, here we extend the optical changing-look (CL) phenomenon occurring in some active galactic nuclei (AGNs) to the optic…

astro-ph.GA2026

Are "Changing-Look" Active Galactic Nuclei Special in the Coevolution of Supermassive Black Holes and their Hosts? II. The Case of Changing-Look Narrow-Line Seyfert 1 Galaxies

J. Wang, S. Jin, D. W. Xu +5

The evolutionary role of the so-called ``changing-look'' (CL) active galactic nucleus (AGN), which is characterized by spectral-type transitions within yr, has been sugges…

astro-ph.GA2025

Departures from Standard Disk Predictions in Intensive Ground-Based Monitoring of Three AGN

Diego Gonzalez-Buitrago, Aaron J. Barth, Rick Edelson +42

We present ground-based, multi-band light curves of the AGN Mrk~509, NGC\,4151, and NGC\,4593 obtained contemporaneously with \sw\, monitoring. We measure cross-correlation lags re…

astro-ph.GA2025

SN 2023ixf in the Pinwheel Galaxy M101: From Shock Breakout to the Nebular Phase

Weikang Zheng, Luc Dessart, Alexei V. Filippenko +39

We present photometric and spectroscopic observations of SN 2023ixf covering from day one to 442 days after explosion. SN 2023ixf reached a peak -band absolute magnitude of $-18…

astro-ph.GA2024★ 16 cited

The most distant HI galaxies discovered by the 500 m dish FAST

Hongwei Xi, Bo Peng, Lister Staveley-Smith +20

Neutral hydrogen (HI) is the primary component of the cool interstellar medium (ISM) and is the reservoir of fuel for star formation. Owing to the sensitivity of existing radio tel…

astro-ph.GA2023★ 13 cited

What Does the Virial Coefficient of the \Hb Broad-Line Region Depend On?

Lizvette Villafaña, Peter R. Williams, Tommaso Treu +37

We combine our dynamical modeling black hole mass measurements from the Lick AGN Monitoring Project 2016 sample with measured cross-correlation time lags and line widths to recover…

astro-ph.GA2023★ 17 cited

AGN STORM 2: II. Ultraviolet Observations of Mrk817 with the Cosmic Origins Spectrograph on the Hubble Space Telescope

Y. Homayouni, Gisella De Rosa, Rachel Plesha +62

We present reverberation mapping measurements for the prominent ultraviolet broad emission lines of the active galactic nucleus Mrk817 using 165 spectra obtained with the Cosmic Or…

astro-ph.GA2022★ 36 cited

The Lick AGN Monitoring Project 2016: Dynamical Modeling of Velocity-Resolved H\b{eta} Lags in Luminous Seyfert Galaxies

Lizvette Villafaña, Peter R. Williams, Tommaso Treu +62

We have modeled the velocity-resolved reverberation response of the H\b{eta} broad emission line in nine Seyfert 1 galaxies from the Lick Active Galactic Nucleus (AGN) Monitioring…

astro-ph.GA2022★ 21 cited

Absolute Calibration of Cepheid Period-Luminosity Relations in NGC 4258

Wenlong Yuan, Lucas M. Macri, Adam G. Riess +6

NGC 4258 is one of the most important anchors for calibrating the Cepheid period--luminosity relations (PLRs) owing to its accurate distance measured from water maser motions. We e…

astro-ph.GA2021

The Lick AGN Monitoring Project 2016: Velocity-Resolved Hβ Lags in Luminous Seyfert Galaxies

Vivian U, Aaron J. Barth, H. Alexander Vogler +61

We carried out spectroscopic monitoring of 21 low-redshift Seyfert 1 galaxies using the Kast double spectrograph on the 3-m Shane telescope at Lick Observatory from April 2016 to M…

astro-ph.GA2020★ 18 cited

Variability and the size-luminosity relation of the intermediate mass AGN in NGC 4395

Hojin Cho, Jong-Hak Woo, Edmund Hodges-Kluck +31

We present the variability study of the lowest-luminosity Seyfert 1 galaxy NGC 4395 based on the photometric monitoring campaigns in 2017 and 2018. Using 22 ground-based and space…

astro-ph.GA2019★ 193 cited

1ES 1927+654: An AGN Caught Changing Look on a Timescale of Months

Benny Trakhtenbrot, Iair Arcavi, Chelsea L. MacLeod +21

We study the sudden optical and ultraviolet (UV) brightening of 1ES 1927+654, which until now was known as a narrow-line active galactic nucleus (AGN). 1ES 1927+654 was part of the…