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Broad-band X-ray observations of the 2018 outburst of the changing-look active galactic nucleus NGC 1566
Ricci, Claudio; Naik, Sachindra; Jana, Arghajit +5 more
We study the nature of the changing-look active galactic nucleus NGC 1566 during its 2018 June outburst. During the outburst, the X-ray intensity of the source rises up to ~25-30 times compared to its quiescent state intensity. We perform timing and spectral analysis of the source during pre-outburst, outburst, and post-outburst epochs using semis…
The KMOS galaxy evolution survey (KGES): the angular momentum of star-forming galaxies over the last ≈10 Gyr
Smail, I.; Swinbank, A. M.; Obreschkow, D. +8 more
We present the KMOS Galaxy Evolution Survey (KGES), a K-band Multi-Object Spectrograph (KMOS) study of the H α and [N II] emission from 288 K-band-selected galaxies at 1.2 ≲ z ≲ 1.8, with stellar masses in the range $\log _{10}(M_{*}/\rm {M}_{\odot })\approx 9$ - 11.5. In this paper, we describe the survey design, present the sample, and discuss t…
Giant Radio Quasars: Sample and Basic Properties
Jamrozy, Marek; Kuźmicz, Agnieszka
We present the largest sample of giant radio quasars (GRQs), which are defined as having a projected linear size greater than 0.7 Mpc. The sample consists of 272 GRQs, of which 174 are new objects discovered through cross-matching the NRAO Very Large Array Sky Survey and the Sloan Digital Sky Survey 14th Data Release Quasar Catalog (DR14Q) and con…
Emergence of Internetwork Magnetic Fields through the Solar Atmosphere
Gošić, M.; De Pontieu, B.; Bellot Rubio, L. R. +2 more
Internetwork (IN) magnetic fields are highly dynamic, short-lived magnetic structures that populate the interior of supergranular cells. Since they emerge all over the Sun, these small-scale fields bring a substantial amount of flux, and therefore energy, to the solar surface. Because of this, IN fields are crucial for understanding the quiet Sun …
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…