Search Publications
Joint analysis of gravitational-wave and electromagnetic data of mergers: breaking an afterglow model degeneracy in GW170817 and in future events
Gianfagna, Giulia; Piro, Luigi; Pannarale, Francesco +4 more
On 2017 August 17, Advanced LIGO and Virgo observed GW170817, the first gravitational-wave (GW) signal from a binary neutron star merger. It was followed by a short-duration gamma-ray burst, GRB 170817A, and by a non-thermal afterglow emission. In this work, a combined simultaneous fit of the electromagnetic (EM, specifically, afterglow) and GW do…
Spectroscopy of CASSOWARY gravitationally lensed galaxies in SDSS: characterization of an extremely bright reionization-era analogue at z = 1.42
Stark, Daniel P.; Ellis, Richard S.; Rigby, Jane R. +3 more
We present new observations of 16 bright (r = 19-21) gravitationally lensed galaxies at z ≃ 1-3 selected from the CASSOWARY survey. Included in our sample is the z = 1.42 galaxy CSWA-141, one of the brightest known reionization-era analogues at high redshift (g = 20.5), with a large specific star formation rate (31.2 Gyr-1) and an [O II…
The formation pathways of compact elliptical galaxies
Forbes, Duncan A.; Drinkwater, Michael J.; Bekki, Kenji +3 more
Compact elliptical (cE) galaxies remain an elusively difficult galaxy class to study. Recent observations have suggested that isolated and host-associated cEs have different formation pathways, while simulation studies have also shown different pathways can lead to a cE galaxy. However, a solid link has not been established, and the relative contr…
The Pristine Inner Galaxy Survey (PIGS) VII: a discovery of the first inner Galaxy CEMP-r/s star
Sestito, F.; González Hernández, J. I.; Arentsen, A. +7 more
Well-studied very metal-poor (VMP, [Fe/H] <-2) stars in the inner Galaxy are few in number, and they are of special interest because they are expected to be among the oldest stars in the Milky Way. We present high-resolution spectroscopic follow-up of the carbon-enhanced metal-poor (CEMP) star Pristine_184237.56-260624.5 (hereafter Pr184237) id…
Main-sequence companions to white dwarfs - II. The age-activity-rotation relation from a sample of Gaia common proper motion pairs
Gänsicke, B. T.; Tremblay, P. -E.; Hollands, M. A. +8 more
Magnetic activity and rotation are related to the age of low-mass main-sequence stars. To further constrain these relations, we study a sample of 574 main-sequence stars members of common proper motion pairs with white dwarfs, identified thanks to Gaia astrometry. We use the white dwarfs as age indicators, while the activity indexes and rotational…
AT2018dyk revisited: a tidal disruption event candidate with prominent infrared echo and delayed X-ray emission in a LINER galaxy
Jiang, Ning; Huang, Shifeng; Wang, Tinggui +2 more
The multiwavelength data of nuclear transient AT2018dyk, initially discovered as a changing-look low-ionization nuclear emission-line region (LINER) galaxy, has been revisited by us and found being in agreement with a tidal disruption event (TDE) scenario. The optical light curve of AT2018dyk declines as a power-law form approximately with index -…
Radio variable and transient sources on minute time-scales in the ASKAP pilot surveys
Bannister, Keith W.; Kaplan, David L.; Lenc, Emil +12 more
We present results from a radio survey for variable and transient sources on 15-min time-scales, using the Australian SKA Pathfinder (ASKAP) pilot surveys. The pilot surveys consist of 505 h of observations conducted at around 1 GHz observing frequency, with a total sky coverage of 1476 deg2. Each observation was tracked for approximate…
DUVET survey: mapping outflows in the metal-poor starburst Mrk 1486
Cameron, Alex J.; Kacprzak, Glenn G.; Chisholm, John +11 more
We present a method to characterize star-formation driven outflows from edge-on galaxies and apply this method to the metal-poor starburst galaxy, Mrk 1486. Our method uses the distribution of emission line flux (from H β and [O III] 5007) to identify the location of the outflow and measure the extent above the disc, the opening angle, and the tra…
Hidden cooling flows in clusters of galaxies - III. Accretion on to the central black hole
Fabian, A. C.; Pinto, C.; Ferland, G. J. +3 more
Recently, we have uncovered hidden cooling flows (HCFs) in the X-ray spectra of the central brightest galaxies of 11 clusters, 1 group, and 2 elliptical galaxies. Here, we report such flows in a further 15 objects, consisting of 8 clusters, 3 groups, 3 ellipticals, and 1 Red Nugget. The mass cooling rates are about $1\hbox{$\hbox{$\rm \, {\rm M}_{…
The relationship between the incidence of X-ray selected AGN in nearby galaxies & star-formation rate
Birchall, Keir L.; Watson, M. G.; Aird, J. +1 more
We present the identification and analysis of an X-ray selected AGN sample that lie within the local (z < 0.35) galaxy population. From a parent sample of 22 079 MPA-JHU (based on SDSS DR8) galaxies, we identified 917 galaxies with central, excess X-ray emission (from 3XMM-DR7) likely originating from an AGN. We measured the host galaxies' star…