Search Publications
Updating the (supermassive black hole mass)-(spiral arm pitch angle) relation: a strong correlation for galaxies with pseudobulges
Graham, Alister W.; Davis, Benjamin L.; Seigar, Marc S.
We have conducted an image analysis of the (current) full sample of 44 spiral galaxies with directly measured supermassive black hole (SMBH) masses, MBH, to determine each galaxy's logarithmic spiral arm pitch angle, ϕ. For predicting black hole masses, we have derived the relation: log (MBH/M⊙) = (7.01 ± 0.07) - (…
Fractal dust constrains the collisional history of comets
Blum, J.; Fulle, M.
The fractal dust particles observed by Rosetta cannot form in the physical conditions observed today in comet 67P/Churyumov-Gerasimenko (67P hereinafter), being instead consistent with models of the pristine dust aggregates coagulated in the solar nebula. Since bouncing collisions in the protoplanetary disc restructure fractals into compact aggreg…
Molecular gas on large circumgalactic scales at z = 3.47
Maiolino, R.; Marconi, A.; Ginolfi, M. +9 more
We report the ALMA observations of the most massive (star-forming) galaxy in the redshift range 3 < z < 4 within the whole Great Observatories Origins Deep Survey South field (GOODS-S) field. We detect a large elongated structure of molecular gas around the massive primeval galaxy, traced by the CO(4-3) emission, and extended over 40 kpc. We…
Cross-correlating Planck tSZ with RCSLenS weak lensing: implications for cosmology and AGN feedback
Heymans, Catherine; Hinshaw, Gary; Harnois-Déraps, Joachim +11 more
We present measurements of the spatial mapping between (hot) baryons and the total matter in the Universe, via the cross-correlation between the thermal Sunyaev-Zeldovich (tSZ) map from Planck and the weak gravitational lensing maps from the Red Cluster Sequence Lensing Survey (RCSLenS). The cross-correlations are performed on the map level where …
On significance of VLBI/Gaia position offsets
Petrov, L.; Kovalev, Y. Y.
We have cross matched the Gaia Data Release 1 secondary data set that contains positions of 1.14 billion objects against the most complete to date catalogue of very long baseline interferometry (VLBI) positions of 11.4 thousand sources, almost exclusively active galactic nuclei. We found 6064 matches, I.e. 53 per cent radio objects. The median unc…
SHARP - IV. An apparent flux-ratio anomaly resolved by the edge-on disc in B0712+472
Vegetti, S.; McKean, J. P.; Auger, M. W. +6 more
Flux-ratio anomalies in quasar lenses can be attributed to dark matter substructure surrounding the lensing galaxy and thus used to constrain the substructure mass fraction. Previous applications of this approach infer a substructure abundance that is potentially in tension with the predictions of Λ cold dark matter cosmology. However, the assumpt…
Dominant dark matter and a counter-rotating disc: MUSE view of the low-luminosity S0 galaxy NGC 5102
Cappellari, Michele; Walcher, C. Jakob; Mitzkus, Martin
The kinematics and stellar populations of the low-mass nearby S0 galaxy NGC 5102 are studied from integral field spectra taken with the Multi-Unit Spectroscopic Explorer. The kinematic maps reveal for the first time that NGC 5102 has the characteristic 2σ peaks indicative of galaxies with counter-rotating discs. This interpretation is quantitative…
Evolution of the ion environment of comet 67P during the Rosetta mission as seen by RPC-ICA
Henri, Pierre; Alho, Markku; Simon Wedlund, Cyril +10 more
Rosetta has followed comet 67P from low activity at more than 3.6 au heliocentric distance to high activity at perihelion (1.24 au) and then out again. We provide a general overview of the evolution of the dynamic ion environment using data from the RPC-ICA ion spectrometer. We discuss where Rosetta was located within the evolving comet magnetosph…
Lessons from the Auriga discs: the hunt for the Milky Way's ex situ disc is not yet over
Monachesi, Antonela; Springel, Volker; Grand, Robert J. J. +7 more
We characterize the contribution from accreted material to the galactic discs of the Auriga Project, a set of high-resolution magnetohydrodynamic cosmological simulations of late-type galaxies performed with the moving-mesh code AREPO. Our goal is to explore whether a significant accreted (or ex situ) stellar component in the Milky Way disc could …
VLT/FORS2 comparative transmission spectroscopy II: Confirmation of a cloud deck and Rayleigh scattering in WASP-31b, but no potassium?
Nikolov, Nikolay; Gibson, Neale P.; Sing, David K. +4 more
We present transmission spectroscopy of the hot-Jupiter WASP-31b using the FOcal Reducer and low dispersion Spectrograph 2 (FORS2) on the Very Large Telescope during two primary transits. The observations cover a wavelength range of ≈400-840 nm. The light curves are corrupted by significant systematics, but these were to first-order invariant with…