Search Publications
Primordial black hole origin for thermal gamma-ray bursts
Barco, Oscar
A binary black hole (BH) astrophysical scenario where a mass-constrained (2.5 × 10-13M⊙) primordial black hole (PBH) undergoes a radial fall on to its heavier component (such as a supermassive black hole, SMBH) is described as an intense gamma-ray emission event. As the relativistic PBH approaches the Schwarschild SMBH event …
The warm-up phase in massive star-forming cores around RCW 120
Wiebe, D. S.; Kirsanova, M. S.; Salii, S. V. +3 more
We study molecular emission in a massive condensation at the border of the H II region RCW 120, paying particular attention to the Core 1 and 2 objects, the most massive fragments of the condensation found previously by ALMA. The latter fragment was previously suggested to host a high-mass analogue of Class 0 young stellar object. We present spect…
Non-equilibrium in the solar neighbourhood using dynamical modelling with Gaia DR2
Kipper, Rain; Tenjes, Peeter; Tempel, Elmo +1 more
Matter distribution models of the Milky Way galaxy are usually stationary, although there are known to be wave-like perturbations in the disc at ~10 per cent level of the total density. Modelling of the overall acceleration field by allowing non-equilibrium is a complicated task. We must learn to distinguish whether density enhancements are persis…
Rapid CO gas dispersal from NO Lup's class III circumstellar disc
Testi, L.; Tazzari, M.; Williams, J. P. +9 more
We observed the K7 class III star NO Lup in an ALMA survey of the 1-3 Myr Lupus association and detected circumstellar dust and CO gas. Here we show that the J = 3-2 CO emission is both spectrally and spatially resolved, with a broad velocity width ~19 km s-1 for its resolved size ~1 arcsec (~130 au). We model the gas emission as a Kepl…
A survey for variable young stars with small telescopes - IV. Rotation periods of YSOs in IC 5070
Scholz, Aleks; Eislöffel, Jochen; Price, Mark C. +50 more
Studying rotational variability of young stars is enabling us to investigate a multitude of properties of young star-disc systems. We utilize high cadence, multiwavelength optical time series data from the Hunting Outbursting Young Stars citizen science project to identify periodic variables in the Pelican Nebula (IC 5070). A double blind study us…
Kinematic complexity around NGC 419: resolving the proper motion of the cluster, the Small Magellanic Cloud, and the Magellanic bridge
Bellini, Andrea; Libralato, Mattia; Massari, Davide +1 more
We present Hubble Space Telescope proper motions in the direction of the star cluster NGC 419 in the Small Magellanic Cloud. Because of the high precision of our measurements, for the first time it is possible to resolve the complex kinematics of the stellar populations located in the field, even along the tangential direction. In fact, the proper…
Estimating black hole masses in obscured AGN using X-rays
Gliozzi, Mario; Williams, James K.; Michel, Dina A.
Determining the black hole masses in active galactic nuclei (AGN) is of crucial importance to constrain the basic characteristics of their central engines and shed light on their growth and co-evolution with their host galaxies. While the black hole mass (MBH) can be robustly measured with dynamical methods in bright type 1 AGN, where t…
The initial properties of young star clusters in M83
Sills, Alison; Webb, Jeremy J.
The initial sizes and masses of massive star clusters provide information about the cluster formation process and also determine how cluster populations are modified and destroyed, which have implications for using clusters as tracers of galaxy assembly. Young massive cluster populations are often assumed to be unchanged since cluster formation; t…
Discovery of an M-type companion to the Herbig Ae Star V1787 Ori
Arun, R.; Mathew, Blesson; Manoj, P. +4 more
The intermediate-mass Herbig Ae star V1787 Ori is a member of the L1641 star-forming region in the Orion A molecular cloud. We report the detection of an M-type companion to V1787 Ori at a projected separation of 6.66 arcsec (corresponding to 2577 au), from the analysis of VLT/NACO adaptive optics Ks-band image. Using astrometric data f…
Dust in RCW 58: Clues to common envelope channel formation?
Marston, A. P.; Toalá, J. A.; Jiménez-Hernández, P. +1 more
We present a characterization of the dust in the Wolf-Rayet (WR) nebula RCW 58 around the WN8h star WR 40 using archival infrared (IR) observations from WISE and Herschel and radio observations from ATCA. We selected two clumps, free from contamination from material along the line of sight and located towards southern regions in RCW 58, as represe…