Search Publications

A Data-driven, Physics-based Transport Model of Solar Energetic Particles Accelerated by Coronal Mass Ejection Shocks Propagating through the Solar Coronal and Heliospheric Magnetic Fields
DOI: 10.3847/1538-4365/accb8e Bibcode: 2023ApJS..266...35Z

Riley, Pete; Zhang, Ming; Lario, David +5 more

In an effort to develop computational tools for predicting radiation hazards from solar energetic particles (SEPs), we have created a data-driven physics-based particle transport model to calculate the injection, acceleration, and propagation of SEPs from coronal mass ejection (CME) shocks traversing through the solar corona and interplanetary mag…

2023 The Astrophysical Journal Supplement Series
SOHO 9
The most luminous, merger-free AGNs show only marginal correlation with bar presence
DOI: 10.1093/mnras/stad966 Bibcode: 2023MNRAS.522..211G

Coil, Alison; Keel, William C.; Simmons, Brooke D. +13 more

The role of large-scale bars in the fuelling of active galactic nuclei (AGNs) is still debated, even as evidence mounts that black hole growth in the absence of galaxy mergers cumulatively dominates and may substantially influence disc (i.e. merger-free) galaxy evolution. We investigate whether large-scale galactic bars are a good candidate for me…

2023 Monthly Notices of the Royal Astronomical Society
eHST 9
Crossing the Rubicon of Reionization with z 5 QSOs
DOI: 10.3847/1538-4357/aceb60 Bibcode: 2023ApJ...955...60G

Grazian, Andrea; Boutsia, Konstantina; Fiore, Fabrizio +12 more

One of the key open questions in cosmology is the nature of sources that completed cosmological hydrogen reionization at z ~ 5.2. High-z primeval galaxies have been long considered the main drivers of reionization, with a minor role played by high-z active galactic nuclei (AGN). However, in order to confirm this scenario, it is fundamental to meas…

2023 The Astrophysical Journal
Gaia 9
Recurring outbursts of the supernova impostor AT 2016blu in NGC 4559
DOI: 10.1093/mnras/stad2702 Bibcode: 2023MNRAS.526..456A

Van Dyk, Schuyler D.; Filippenko, Alexei V.; Smith, Nathan +8 more

We present the first photometric analysis of the supernova (SN) impostor AT 2016blu in NGC 4559. This transient was discovered by the Lick Observatory Supernova Search in 2012 and has continued its outbursts since then. Optical and infrared photometry of AT 2016blu reveals at least 19 outbursts in 2012-2022. Similar photometry from 1999 to 2009 sh…

2023 Monthly Notices of the Royal Astronomical Society
eHST 9
Revisiting empirical solar energetic particle scaling relations. I. Solar flares
DOI: 10.1051/0004-6361/202243407 Bibcode: 2023A&A...671A..66P

Veronig, Astrid M.; Papaioannou, Athanasios; Herbst, Konstantin +3 more


Aims: The possible influence of solar superflares on the near-Earth space radiation environment are assessed through the investigation of scaling laws between the peak proton flux and fluence of solar energetic particle (SEP) events with the solar flare soft X-ray peak photon flux.
Methods: We compiled a catalog of 65 well-connected (W20…

2023 Astronomy and Astrophysics
SOHO 9
Characterization and dynamics of the peculiar stream Jhelum. A tentative role for the Sagittarius dwarf galaxy
DOI: 10.1051/0004-6361/202243266 Bibcode: 2023A&A...669A.102W

Helmi, Amina; Woudenberg, Hanneke C.; Balbinot, Eduardo +1 more

Context. Stellar streams are a promising tool to study the Milky Way's dark matter subhalo population, as interactions with subhalos are expected to leave visible imprints in the streams in the form of substructure. However, there may be other causes of substructure.
Aims: Here we studied the kinematics and the unusual morphology of the stell…

2023 Astronomy and Astrophysics
Gaia 9
Compact [C II] emitters around a C IV absorption complex at redshift 5.7
DOI: 10.1038/s41586-023-05901-3 Bibcode: 2023Natur.617..261K

Simcoe, Robert A.; Kashino, Daichi; Eilers, Anna-Christina +4 more

The physical conditions of the circumgalactic medium are investigated by means of intervening absorption-line systems in the spectrum of background quasi-stellar objects (QSOs) out to the epoch of cosmic reionization1-4. A correlation between the ionization state of the absorbing gas and the nature of the nearby galaxies has been sugges…

2023 Nature
eHST 9
Lack of Correlations between Cold Molecular Gas and AGN Properties in Type 1 AGNs at z ≲ 0.5
DOI: 10.3847/1538-4357/acc9b4 Bibcode: 2023ApJ...950...60M

Ho, Luis C.; Bauer, Franz E.; Treister, Ezequiel +3 more

We present new NOrthern Extended Millimeter Array (NOEMA) observations of the CO(2-1) emission in eight of the brightest Palomar-Green quasars at z ≲ 0.5 to investigate the role of active galactic nucleus (AGN) feedback in luminous quasars detected at low redshifts. We detect CO(2-1) emission in three objects, from which we derive CO luminosities,…

2023 The Astrophysical Journal
Herschel 9
Detection of TiO and VO in the Atmosphere of WASP-121b and Evidence For its Temporal Variation
DOI: 10.1088/1674-4527/accbb2 Bibcode: 2023RAA....23f5010O

Zhao, Gang; Wang, Wei; Zhao, Fei +6 more

We report the transit observations of the ultra-hot Jupiter WASP-121b using the Goodman High Throughput Spectrograph at the 4 m ground-based Southern Astrophysical Research Telescope, covering the wavelength range 502-900 nm. By dividing the target and reference star into 19 spectroscopic passbands and applying differential spectrophotometry, we d…

2023 Research in Astronomy and Astrophysics
eHST 9
The evolution of the internal structure of massive star-forming regions in the Milky Way as revealed by ALMA
DOI: 10.1093/mnras/stad1904 Bibcode: 2023MNRAS.524.1625D

Dib, Sami

We analyse the structure of 15 protocluster forming regions in the Milky Way using their 1.3 mm continuum emission maps from the ALMA-IMF large program. The analysis of the cloud structure is performed using the delta-variance spectrum technique. The calculated spectra display a self-similar regime on small scales as well as the presence of a prom…

2023 Monthly Notices of the Royal Astronomical Society
Herschel 9