Search Publications
No Redshift Evolution of Galaxies' Dust Temperatures Seen from 0 < z < 2
Casey, Caitlin M.; Drew, Patrick M.
Some recent literature has claimed there to be an evolution in galaxies' dust temperatures toward warmer (or colder) spectral energy distributions (SEDs) between low and high redshift. These conclusions are driven by both theoretical models and empirical measurement. Such claims sometimes contradict one another and are prone to biases in samples o…
On the Role of Coronal Shocks for Accelerating Solar Energetic Electrons
Kouloumvakos, Athanasios; Dresing, Nina; Vainio, Rami +1 more
We study the role of coronal mass ejection (CME) driven shocks in the acceleration of solar energetic electrons. Using observations by the two STEREO spacecraft, we correlate electron peak intensities of solar energetic particle events measured in situ with various parameters of the associated coronal shocks. These shock parameters were derived by…
The Number Densities and Stellar Populations of Massive Galaxies at 3 < z < 6: A Diverse, Rapidly Forming Population in the Early Universe
Muzzin, Adam; Forrest, Ben; Marchesini, Danilo +9 more
We present the census of massive (log(M */M ⊙) > 11) galaxies at 3 < z < 6 identified over the COSMOS/UltraVISTA Ultra-Deep field stripes: consisting of ≈100 and ≈20 high-confidence candidates at 3 < z < 4 and 4 < z < 6, respectively. The 3 < z < 4 population is comprised of post-starburst, UV-star-…
Particle energization in space plasmas: towards a multi-point, multi-scale plasma observatory
Sorriso-Valvo, Luca; Retinò, Alessandro; McWilliams, Kathryn +27 more
This White Paper outlines the importance of addressing the fundamental science theme "How are charged particles energized in space plasmas" through a future ESA mission. The White Paper presents five compelling science questions related to particle energization by shocks, reconnection, waves and turbulence, jets and their combinations. Answering t…
A Radio, Optical, UV, and X-Ray View of the Enigmatic Changing-look Active Galactic Nucleus 1ES 1927+654 from Its Pre- to Postflare States
Cenko, S. Bradley; Meyer, Eileen; Lusso, Elisabeta +17 more
The nearby Type II active galactic nucleus (AGN) 1ES 1927+654 went through a violent changing-look (CL) event beginning 2017 December during which the optical and UV fluxes increased by four magnitudes over a few months, and broad emission lines newly appeared in the optical/UV. By 2018 July, the X-ray coronal emission had completely vanished, onl…
Accurate Machine-learning Atmospheric Retrieval via a Neural-network Surrogate Model for Radiative Transfer
Arney, Giada N.; Domagal-Goldman, Shawn D.; Harrington, Joseph +8 more
Atmospheric retrieval determines the properties of an atmosphere based on its measured spectrum. The low signal-to-noise ratios of exoplanet observations require a Bayesian approach to determine posterior probability distributions of each model parameter, given observed spectra. This inference is computationally expensive, as it requires many exec…
CHEX-MATE: Morphological analysis of the sample
Pointecouteau, E.; Pratt, G. W.; Rossetti, M. +17 more
A classification of the galaxy cluster's dynamical state is crucial when dealing with large samples. The identification of the most relaxed and most disturbed objects is necessary for both cosmological analysis, focused on spherical and virialised systems, and astrophysical studies, centred around all those micro-physical processes that take place…
HATS-74Ab, HATS-75b, HATS-76b, and HATS-77b: Four Transiting Giant Planets Around K and M Dwarfs
Hobson, M.; Jordán, Andrés; Palle, E. +35 more
The relative rarity of giant planets around low-mass stars compared with solar-type stars is a key prediction from the core-accretion planet formation theory. In this paper we report on the discovery of four gas giant planets that transit low-mass late K and early M dwarfs. The planets HATS-74Ab (TOI 737b), HATS-75b (TOI 552b), HATS-76b (TOI 555b)…
The Rate, Amplitude, and Duration of Outbursts from Class 0 Protostars in Orion
Manoj, P.; Narang, Mayank; Pokhrel, Riwaj +18 more
At least half of a protostar's mass is accreted in the Class 0 phase, when the central protostar is deeply embedded in a dense, infalling envelope. We present the first systematic search for outbursts from Class 0 protostars in the Orion clouds. Using photometry from Spitzer/IRAC spanning 2004 to 2017, we detect three outbursts from Class 0 protos…
COCONUT, a Novel Fast-converging MHD Model for Solar Corona Simulations: I. Benchmarking and Optimization of Polytropic Solutions
Poedts, Stefaan; Zhang, Fan; Perri, Barbara +5 more
We present a novel global 3D coronal MHD model called COCONUT, polytropic in its first stage and based on a time-implicit backward Euler scheme. Our model boosts run-time performance in comparison with contemporary MHD-solvers based on explicit schemes, which is particularly important when later employed in an operational setting for space-weather…