Search Publications
Dust and power: Unravelling the merger-active galactic nucleus connection in the second half of cosmic history
Wang, L.; Davé, R.; Yang, G. +8 more
Aims. Galaxy mergers represent a fundamental physical process under hierarchical structure formation, but their role in triggering active galactic nuclei (AGNs) is still unclear. We aim to investigate the merger-AGN connection using state-of-the-art observations and novel methods for detecting mergers and AGNs. Methods. We selected stellar mass-li…
Radial phase spirals in the Solar neighbourhood
Price-Whelan, Adrian M.; Horta, Danny; Johnston, Kathryn V. +4 more
The second data release of ESA's Gaia mission revealed numerous signatures of disequilibrium in the Milky Way's disc. These signatures are seen in the planar kinematics of stars, which manifest as ridges and ripples in R-vϕ, and in vertical kinematics, where a prominent spiral is seen in the z-vz phase space. In this work, we…
JWST and ALMA Discern the Assembly of Structural and Obscured Components in a High-redshift Starburst Galaxy
Casey, Caitlin M.; Kartaltepe, Jeyhan S.; Koekemoer, Anton M. +27 more
We present observations and analysis of the starburst PACS-819 at z = 1.45 (M * = 1010.7 M ⊙), using high-resolution (0.″1; 0.8 kpc) Atacama Large Millimeter/submillimeter Array (ALMA) and multiwavelength JWST images from the COSMOS-Web program. Dissimilar to Hubble Space Telescope (HST) ACS images in the rest-fram…
Broadband X-ray/UV/optical time-resolved spectroscopy of NGC 5548: The origin of the UV/optical variability in active galactic nuclei
Papadakis, I. E.; Dovčiak, M.; Kammoun, E. +1 more
Context. Recently, nearby bright galaxies have been the subject of long monitoring surveys in the X-rays, UV, and optical. All of these campaigns revealed a strong correlation between the various UV and optical bands, with time lags that increase with wavelength. In a series of papers, we have demonstrated that a scenario in which an X-ray source …
Investigating episodic mass loss in evolved massive stars. I. Spectroscopy of dusty massive stars in ten southern galaxies
Zapartas, E.; de Wit, S.; Bonanos, A. Z. +7 more
Context. Episodic mass-loss events such as giant eruptions in luminous blue variables or pre-supernova eruptions in red supergiants drastically alter the evolutionary path of a massive star, resulting in a rich and complex circumstellar environment and IR excess. However, the incidence of these events, and hence their importance in massive star ev…
SMA 200–400 GHz Survey for Dust Properties in the Icy Class II Disks in the Taurus Molecular Cloud
Liu, Hauyu Baobab; Andrews, Sean M.; Long, Feng +4 more
We present a new Submillimeter Array survey of 47 Class II sources in the Taurus–Auriga region. Our observations made 12 independent samples of flux densities over the 200–400 GHz frequency range. We tightly constrained the spectral indices of most sources to a narrow range of 2.0 ± 0.2; only a handful of spatially resolved (e.g., diameter >250…
Discovery of a new blue large-amplitude pulsator in the SkyMapper DR2: SMSS J184506.82-300804.7
Wolf, Christian; Onken, Christopher A.; Bessell, Michael S. +1 more
We report the discovery of a new Blue Large-Amplitude Pulsator (BLAP), SMSS J184506-300804 (SMSS-BLAP-1) in Data Release 2 of the SkyMapper Southern Sky Survey. We conduct high-cadence photometric observations in the u band to confirm a periodic modulation of the light curve. SMSS-BLAP-1 has a ~19-min pulsation period with an amplitude of 0.2 mag …
Potential biases and prospects for the Hubble constant estimation via electromagnetic and gravitational-wave joint analyses
Gianfagna, Giulia; Piro, Luigi; Pannarale, Francesco +3 more
GW170817 is a binary neutron star merger that exhibited a gravitational wave (GW) and a gamma-ray burst, followed by an afterglow. In this work, we estimate the Hubble constant (H0) using broad-band afterglow emission and relativistic jet motion from the Very Long Baseline Interferometry and HST images of GW170817. Compared to previous …
A Pileup of Coronal Mass Ejections Produced the Largest Geomagnetic Storm in Two Decades
Wang, Rui; Liu, Ying D.; Hu, Huidong +2 more
The largest geomagnetic storm in two decades occurred in 2024 May with a minimum D st of ‑412 nT. We examine its solar and interplanetary origins by combining multipoint imaging and in situ observations. The source active region, NOAA AR 13664, exhibited extraordinary activity and produced successive halo eruptions, which were responsib…
High mass function ellipsoidal variables in the Gaia Focused Product Release: searching for black hole candidates in the binary zoo
Kochanek, Christopher S.; Thompson, Todd A.; Jayasinghe, Tharindu +2 more
The recent Gaia Focused Product Release contains radial velocity time-series for more than 9,000 Gaia long-period photometric variables. Here we search for binary systems with large radial velocity amplitudes to identify candidates with massive, unseen companions. Eight targets have binary mass function f(M)>1M⊙, three of which are eclipsing bi…