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AD Leonis : Radial velocity signal of stellar rotation or spin-orbit resonance?
(2018-04-16)
AD Leonis is a nearby magnetically active M dwarf. We find Doppler variability with a period of 2.23 days, as well as photometric signals: (1) a short-period signal, which is similar to the radial velocity signal, albeit ...
LOFAR-Boötes : Properties of high- and low-excitation radio galaxies at 0.5 < z < 2.0
(2018-04-11)
This paper presents a study of the redshift evolution of radio-loud active galactic nuclei (AGN) as a function of the properties of their galaxy hosts in the Boötes field. To achieve this we match low-frequency radio sources ...
The Initial mass function of the first stars inferred from extremely metal-poor stars
(2018-04-11)
We compare the elemental abundance patterns of ~200 extremely metal-poor (EMP; [Fe/H] < −3) stars to the supernova yields of metal-free stars, in order to obtain insights into the characteristic masses of the first (Population ...
The ALMA view of GMCs in NGC 300 : Physical Properties and Scaling Relations at 10 pc Resolution
(2018-04-09)
We have conducted a 12CO(2-1) survey of several molecular gas complexes in the vicinity of H ii regions within the spiral galaxy NGC 300 using the Atacama Large Millimeter Array (ALMA). Our observations attain a resolution ...
A formation timescale of the Galactic halo from Mg isotopes in dwarf stars
(2018-04-04)
We determine magnesium isotopic abundances of metal-poor dwarf stars from the galactic halo, to shed light on the onset of asymptotic giant branch (AGB) star nucleosynthesis in the galactic halo and constrain the timescale ...
MUSE observations of the counter-rotating nuclear ring in NGC 7742
(2018-04-01)
Aims. We present results from MUSE observations of the nearly face-on disk galaxy NGC 7742. This galaxy hosts a spectacular nuclear ring of enhanced star formation, which is unusual in that it is hosted by a non-barred ...
A 1.3 mm SMA Survey of 29 Variable Young Stellar Objects
(2018-04-01)
Context. Young stellar objects (YSOs) may undergo periods of active accretion (outbursts), during which the protostellar accretion rate is temporarily enhanced by a few orders of magnitude. Whether or not these accretion ...
A simulation-based analytic model of radio galaxies
(2018-04-01)
I derive and discuss a simple semi-analytical model of the evolution of powerful radio galaxies which is not based on assumptions of self-similar growth, but rather implements some insights about the dynamics and energetics ...
Gathering dust : A galaxy-wide study of dust emission from cloud complexes in NGC 300
(2018-04-01)
Aims. We use multi-band observations by the Herschel Space Observatory to study the dust emission properties of the nearby spiral galaxy NGC 300. We compile a first catalogue of the population of giant dust clouds (GDCs) ...
A and F stars as probes of outer Galactic disc kinematics
(2018-04-01)
Previous studies of the rotation law in the outer Galactic disc have mainly used gas tracers or clump giants. Here, we explore A and F stars as alternatives: these provide a much denser sampling in the outer disc than gas ...