Search Publications
Slow wind belt in the quiet solar corona
Romoli, M.; Andretta, V.; Uslenghi, M. +16 more
The slow solar wind belt in the quiet corona, observed with the Metis coronagraph on board Solar Orbiter on May 15, 2020, during the activity minimum of the cycle 24, in a field of view extending from 3.8 R ⊙ to 7.0 R ⊙, is formed by a slow and dense wind stream running along the coronal current sheet, accelerating in the radial direction and reac…
The dusty circumstellar environment of Betelgeuse during the Great Dimming as seen by VLTI/MATISSE
Danchi, W.; Matter, A.; Lopez, B. +23 more
Context. The `Great Dimming' of the prototypical red supergiant Betelgeuse, which occurred between December 2019 and April 2020, gives us unprecedented insight into the processes occurring on the stellar surface and in the inner wind of this type of star. In particular it may bring further understanding of their dust nucleation and mass-loss proce…
Detection of Strongly Lensed Arcs in Galaxy Clusters with Transformers
Li, Nan; Luo, Rui; Jia, Peng +4 more
Strong lensing in galaxy clusters probes properties of dense cores of dark matter halos in mass, studies the distant universe at flux levels and spatial resolutions otherwise unavailable, and constrains cosmological models independently. The next-generation large-scale sky imaging surveys are expected to discover thousands of cluster-scale strong …
An Energetic Eruption With Associated SO 1.707 Micron Emissions at Io's Kanehekili Fluctus and a Brightening Event at Loki Patera Observed by JWST
de Pater, Imke; Wong, Michael H.; Hedman, Matthew M. +24 more
We observed Io with the James Webb Space Telescope (JWST) while the satellite was in eclipse, and detected thermal emission from several volcanoes. The data were taken as part of our JWST-ERS program #1373 on 15 November 2022. Kanehekili Fluctus was exceptionally bright, and Loki Patera had most likely entered a new brightening phase. Spectra were…
Outflow densities and ionization mechanisms in the NLRs of the prototypical Seyfert galaxies NGC 1068 and NGC 4151
Holden, Luke R.; Tadhunter, Clive N.
Despite being thought to play an important role in galaxy evolution, the true impact of outflows driven by active galactic nuclei (AGNs) on their host galaxies is unclear. In part, this may be because electron densities of outflowing gas are often underestimated: recent studies that use alternative diagnostics have measured much higher densities t…
GOALS-JWST: NIRCam and MIRI Imaging of the Circumnuclear Starburst Ring in NGC 7469
Inami, Hanae; Böker, Torsten; Kemper, Francisca +30 more
We present James Webb Space Telescope (JWST) imaging of NGC 7469 with the Near-Infrared Camera and the Mid-InfraRed Instrument. NGC 7469 is a nearby, z = 0.01627, luminous infrared galaxy that hosts both a Seyfert Type-1.5 nucleus and a circumnuclear starburst ring with a radius of ~0.5 kpc. The new near-infrared (NIR) JWST imaging reveals 66 star…
NICER/NuSTAR Characterization of 4U 1957+11: A Near Maximally Spinning Black Hole Potentially in the Mass Gap
Steiner, James F.; Remillard, Ronald A.; Grinberg, Victoria +5 more
4U 1957+11 is a black hole candidate system that has been in a soft X-ray spectral state since its discovery. We present analyses of recent joint NICER and NuSTAR spectra, which are extremely well described by a highly inclined disk accreting into a near maximally spinning black hole. Owing to the broad X-ray coverage of NuSTAR, the fitted spin an…
Exploring the correlation between Hα-to-UV ratio and burstiness for typical star-forming galaxies at z 2
Siana, Brian; Shapley, Alice E.; Reddy, Naveen A. +12 more
The $\rm {H}\alpha$-to-UV luminosity ratio ($L(\text{H}\alpha)/L(\rm UV)$) is often used to probe bursty star formation histories (SFHs) of star-forming galaxies and it is important to validate it against other proxies for burstiness. To address this issue, we present a statistical analysis of the resolved distribution of star formation rate surfa…
Optical polarization from colliding stellar stream shocks in a tidal disruption event
Blinov, D.; Liodakis, I.; Berton, M. +9 more
A tidal disruption event (TDE) occurs when a supermassive black hole rips apart a passing star. Part of the stellar material falls toward the black hole, forming an accretion disk that in some cases launches a relativistic jet. We performed optical polarimetry observations of a TDE, AT 2020mot. We find a peak linear polarization degree of 25 ± 4%,…
Hidden deep in the halo: selection of a reduced proper motion halo catalogue and mining retrograde streams in the velocity space
Helmi, Amina; Starkenburg, Else; Viswanathan, Akshara +3 more
The Milky Way halo is one of the few galactic haloes that provides a unique insight into galaxy formation by resolved stellar populations. Here, we present a catalogue of ~47 million halo stars selected independent of parallax and line-of-sight velocities, using a combination of Gaia DR3 proper motion and photometry by means of their reduced prope…