Search Publications
GASTON: Galactic Star Formation with NIKA2 - evidence for the mass growth of star-forming clumps
Berta, S.; Aussel, H.; Adam, R. +44 more
Determining the mechanism by which high-mass stars are formed is essential for our understanding of the energy budget and chemical evolution of galaxies. By using the New IRAM KIDs Array 2 (NIKA2) camera on the Institut de Radio Astronomie Millimétrique (IRAM) 30-m telescope, we have conducted high-sensitivity and large-scale mapping of a fraction…
Fundamental differences in the radio properties of red and blue quasars: kiloparsec-scale structures revealed by e-MERLIN
Thomson, A. P.; Alexander, D. M.; Rosario, D. J. +5 more
Red quasi-stellar objects (QSOs) are a subset of the quasar population with colours consistent with reddening due to intervening dust. Recent work has demonstrated that red QSOs show special radio properties that fundamentally distinguish them from normal blue QSOs, specifically a higher incidence of low-power radio emission (1.4 GHz luminosities …
A2A: 21 000 bulge stars from the ARGOS survey with stellar parameters on the APOGEE scale
Freeman, K. C.; Bland-Hawthorn, J.; Ness, M. K. +3 more
Aims: Spectroscopic surveys have by now collectively observed tens of thousands of stars in the bulge of our Galaxy. However, each of these surveys had unique observing and data processing strategies that led to distinct stellar parameter and abundance scales. Because of this, stellar samples from different surveys cannot be directly combined…
What controls the UV-to-X-ray continuum shape in quasars?
Brandt, W. N.; Laor, Ari; Timlin, John D., III
We present an investigation of the interdependence of the optical-to-X-ray spectral slope (αox), the He II equivalent-width (EW), and the monochromatic luminosity at 2500 Å (L2500). The values of αox and He II EW are indicators of the strength/shape of the quasar ionizing continuum, from the ultraviolet (UV; 1500-2…
A Hubble Space Telescope Imaging Survey of Low-redshift Swift-BAT Active Galaxies
Ho, Luis C.; Barth, Aaron J.; Kim, Minjin +1 more
We present initial results from a Hubble Space Telescope snapshot imaging survey of the host galaxies of Swift-BAT active galactic nuclei (AGN) at z < 0.1. The hard X-ray selection makes this sample relatively unbiased in terms of obscuration, compared to optical AGN selection methods. The high-resolution images of 154 target AGN enable us to i…
Transient obscuration event captured in NGC 3227. I. Continuum model for the broadband spectral energy distribution
Kaastra, J. S.; Kriss, G. A.; Arav, N. +21 more
From Swift monitoring of a sample of active galactic nuclei (AGN) we found a transient X-ray obscuration event in Seyfert-1 galaxy NGC 3227, and thus triggered our joint XMM-Newton, NuSTAR, and Hubble Space Telescope (HST) observations to study this event. Here in the first paper of our series we present the broadband continuum modelling of the sp…
The Effects of Biconical Outflows on Lyα Escape from Green Peas
Scarlata, Claudia; Henry, Alaina; Carr, Cody +1 more
We analyze the spectra of 10 Green Pea galaxies, previously studied by Henry et al., using a semi-analytical line transfer model to interpret emission and absorption features observed in UV galactic spectra. We focus our analysis on various ionization states of silicon, associated with the cool (∼104 K) and warm (∼105 K) gas.…
Propagating brightenings in small loop-like structures in the quiet-Sun corona: Observations from Solar Orbiter/EUI
Teriaca, Luca; Solanki, Sami K.; Schühle, Udo +6 more
Brightenings observed in solar extreme-ultraviolet images are generally interpreted as signatures of micro- or nanoflares occurring in the transition region or at coronal temperatures. Recent observations with the Extreme Ultraviolet Imager (EUI) on board Solar Orbiter have revealed the smallest of such brightenings (called campfires) in the quiet…
Galaxy Properties at the Faint End of the H I Mass Function
McQuinn, Kristen B. W.; Cannon, John M.; Dolphin, Andrew E. +9 more
The Survey of H I in Extremely Low-mass Dwarfs (SHIELD) includes a volumetrically complete sample of 82 gas-rich dwarfs with ${M}_{{\rm{H}}\,{\rm\small{I}}}\lesssim {10}^{7.2}$ ${M}_{\odot }$ selected from the ALFALFA survey. We are obtaining extensive follow-up observations of the SHIELD galaxies to study their gas, stellar, and chemical content,…
Evaluating Stereo Digital Terrain Model Quality at Mars Rover Landing Sites with HRSC, CTX, and HiRISE Images
Kirk, Randolph L.; Fergason, Robin L.; Gwinner, Klaus +4 more