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The thermal and non-thermal components within and between galaxy clusters Abell 399 and Abell 401
Sarazin, Craig L.; Hilton, Matt; Sifón, Cristóbal +28 more
We measure the local correlation between radio emission and Compton-y signal across two galaxy clusters, Abell 399 and Abell 401, using maps from the Low Frequency Array and the Atacama Cosmology Telescope + Planck. These data sets allow us to make the first measurement of this kind at ~arcmin resolution. We find that the radio brightness scales a…
The morphology of the ejecta of SN 1987A at 31 yr from 1150 to 10 000 Å
Larsson, J.; Sollerman, J.; Lundqvist, P. +7 more
We present spectroscopy of the ejecta of SN 1987A in 2017 and 2018 from the Hubble Space Telescope and the Very Large Telescope, covering the wavelength range between 1150 and $10\, 000$ Å. At 31 yr, this is the first epoch with coverage over the ultraviolet-to-near-infrared range since 1995. We create velocity maps of the ejecta in the H α, Mg II…
The Hot Neptune WASP-166 b with ESPRESSO - I. Refining the planetary architecture and stellar variability
Lafarga, M.; Lendl, M.; Lovis, C. +24 more
In this paper, we present high-resolution spectroscopic transit observations from ESPRESSO of the super-Neptune WASP-166 b. In addition to spectroscopic ESPRESSO data, we analyse photometric data from TESS of six WASP-166 b transits along with simultaneous NGTS observations of the ESPRESSO runs. These observations were used to fit for the planetar…
Inflow of low-metallicity cool gas in the halo of the Andromeda galaxy
Afruni, Andrea; Fraternali, Filippo; Pezzulli, Gabriele
As the closest L* galaxy to our own Milky Way, the Andromeda galaxy (M31) is an ideal laboratory for studies of galaxy evolution. The AMIGA project has recently provided observations of the cool (T ~ 104 K) phase of the circumgalactic medium (CGM) of M31, using HST/COS absorption spectra along ~40 background QSO sightlines, located up t…
Unprecedented change in the position of four radio sources
Frey, Sándor; Melnikov, Alexey; Titov, Oleg +8 more
Astrometric positions of radio-emitting active galactic nuclei (AGNs) can be determined with sub-milliarcsec accuracy using very long baseline interferometry (VLBI). The usually small apparent proper motion of distant extragalactic targets allow us to realize the fundamental celestial reference frame with VLBI observations. However, long-term astr…
Evidence for anisotropic quenching in massive galaxy clusters at z ≈ 0.5
Stott, John P.
A recent observational result finds that the quenching of satellites in groups at z = 0.08 has an angular dependence relative to the semimajor axis of the central galaxy. This observation is described as 'anisotropic quenching' or 'angular conformity'. In this paper, I study the variation in the colour of a mass-limited sample of satellite galaxie…
Dynamics of irregularly shaped cometary particles subjected to outflowing gas and solar radiative forces and torques
Bertini, Ivano; Fulle, Marco; Moreno, Fernando +6 more
The dynamics of irregularly shaped particles subjected to the combined effect of gas drag and radiative forces and torques in a cometary environment is investigated. The equations of motion are integrated over distances from the nucleus surface up to distances where the gas drag is negligible. The aerodynamic forces and torques are computed assumi…
Stellar masses of clumps in gas-rich, turbulent disc galaxies
Glazebrook, Karl; Lenkić, Laura; Fisher, Deanne B. +6 more
In this paper, we use Hubble Space Telescope/WFC3 observations of six galaxies from the DYnamics of Newly Assembled Massive Object (DYNAMO) survey, combined with stellar population modelling of the SED, to determine the stellar masses of DYNAMO clumps. The DYNAMO sample has been shown to have properties similar to z ≈ 1.5 turbulent, clumpy discs. …
Black hole spin measurements based on a thin disc model with finite thickness - I. An example study of MCG-06-30-15
Reynolds, Christopher S.; Abdikamalov, Askar B.; Bambi, Cosimo +1 more
We present a re-analysis of the XMM-Newton and NuSTAR observing campaigns for the well-studied, X-ray-bright AGN MCG-06-30-15. In particular, we consider a disc model with finite thickness. By fitting the disc reflection spectra in the data, we obtain a black hole spin of 0.87-0.99 (90 per cent confidence range) after taking the thickness of the d…
Multi-wavelength constraints on the outflow properties of the extremely bright millisecond radio bursts from the galactic magnetar SGR 1935 + 2154
Murase, Kohta; Kashiyama, Kazumi; Yamasaki, Shotaro
Extremely bright coherent radio bursts with millisecond duration, reminiscent of cosmological fast radio bursts, were codetected with anomalously-hard X-ray bursts from a Galactic magnetar SGR 1935 + 2154. We investigate the possibility that the event was triggered by the magnetic energy injection inside the magnetosphere, thereby producing magnet…