Search Publications
On the gravitational lensing interpretation of three gravitational wave detections in the mass gap by LIGO and Virgo
Richard, Johan; Smith, Graham P.; Massey, Richard +7 more
We search for gravitational wave (GW) events from LIGO-Virgo's third run that may have been affected by gravitational lensing. Gravitational lensing delays the arrival of GWs, and alters their amplitude - thus biasing the inferred progenitor masses. This would provide a physically well-understood interpretation of GW detections in the 'mass gap' b…
Arecibo and FAST timing follow-up of 12 millisecond pulsars discovered in Commensal Radio Astronomy FAST Survey
Wang, P.; Kramer, M.; Zhang, L. +46 more
We report the phase-connected timing ephemeris, polarization pulse profiles, Faraday rotation measurements, and Rotating-Vector-Model (RVM) fitting results of 12 millisecond pulsars (MSPs) discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in the Commensal Radio Astronomy FAST survey (CRAFTS). The timing campaigns wer…
The Pristine dwarf galaxy survey-V. The edges of the dwarf galaxy Hercules
Sestito, Federico; Martin, Nicolas; Malhan, Khyati +6 more
We present a new spectroscopic study of 175 stars in the vicinity of the dwarf galaxy Hercules (d ~ 132 kpc) with data from the Anglo-Australian Telescope and its AAOmega spectrograph together with the Two Degree Field multi-object system to solve the conundrum that whether Hercules is tidally disrupting. We combine broad-band photometry, proper m…
Spectroscopy of QUBRICS quasar candidates: 1672 new redshifts and a golden sample for the Sandage test of the redshift drift
Grazian, Andrea; Boutsia, Konstantina; Cupani, Guido +10 more
The QUBRICS (QUasars as BRIght beacons for Cosmology in the Southern hemisphere) survey aims at constructing a sample of the brightest quasars with $z \lower.5ex\hbox{$\,\, \buildrel\gt \over \sim \,\,$}2.5$, observable with facilities in the Southern Hemisphere. QUBRICS makes use of the available optical and IR wide-field surveys in the South and…
JWST photometry of globular cluster populations in Abell 2744 at z = 0.3
Harris, William E.; Reina-Campos, Marta
JWST imaging of the rich galaxy cluster Abell 2744 at z = 0.308 has been used by the UNCOVER team to construct mosaic images in the NIRCam filters. The exceptionally deep images in the (F115W, F150W, and F200W) bands reveal a large population of unresolved point-like sources across the field, the vast majority of which are globular clusters (GCs) …
Planetesimals at DZ stars - I. Chondritic compositions and a massive accretion event
Dufour, Patrick; Desch, Steven J.; Melis, Carl +4 more
There is a wealth of evidence to suggest that planetary systems can survive beyond the main sequence. Most commonly, white dwarfs are found to be accreting material from tidally disrupted asteroids, whose bulk compositions are reflected by the metals polluting the stellar photospheres. While many examples are known, most lack the deep, high-resolu…
Identifying the SN 2022acko progenitor with JWST
Van Dyk, Schuyler D.; Filippenko, Alexei V.; Sand, David J. +17 more
We report on analysis using the JWST to identify a candidate progenitor star of the Type II-plateau (II-P) supernova SN 2022acko in the nearby, barred spiral galaxy NGC 1300. To our knowledge, our discovery represents the first time JWST has been used to localize a progenitor system in pre-explosion archival Hubble Space Telescope (HST) images. We…
Extreme broad He II emission at high and low redshifts: the dominant role of VMS in NGC 3125-A1 and CDFS131717
Hayes, Matthew; Smith, Linda J.; Charlot, Stephane +6 more
Super star cluster (SSC) A1 ($3.1\times 10^5\, \mathrm{M}_\odot$) in NGC 3125 has one of the strongest ($EW=4.6\pm 0.5\,$ Å) broad ($FWHM=1131\pm 40\,$ km s-1) He II λ1640 emission lines in the nearby universe and constitutes an important template for interpreting observations of extreme He II emitters out to redshifts of z ~ 2 - 3. We …
Multi-spacecraft observations of shocklets at an interplanetary shock
Vainio, R.; Horbury, T.; Dresing, N. +5 more
Interplanetary (IP) shocks are fundamental building blocks of the heliosphere, and the possibility to observe them in situ is crucial to address important aspects of energy conversion for a variety of astrophysical systems. Steepened waves known as shocklets are known to be important structures of planetary bow shocks, but they are very rarely obs…
Planet engulfment signatures in twin stars
Behmard, Aida; Fuller, Jim; Sevilla, Jason
Planet engulfment can be inferred from enhancement of refractory elements in the photosphere of the engulfing star following accretion of rocky planetary material. Such refractory enrichments are subject to stellar interior mixing processes, namely thermohaline mixing induced by an inverse mean-molecular-weight gradient between the convective enve…