Search Publications
Chemical enrichment in the cool core of the Centaurus cluster of galaxies
Matsushita, Kyoko; Fukushima, Kotaro; Kobayashi, Shogo B.
Here, we present results from over 500 ksChandra and XMM-Newton observations of the cool core of the Centaurus cluster. We investigate the spatial distributions of the O, Mg, Si, S, Ar, Ca, Cr, Mn, Fe, and Ni abundances in the intracluster medium with CCD detectors, and those of N, O, Ne, Mg, Fe, and Ni with the Reflection Grating Spectrometer (RG…
ESO 137-002: a large spiral undergoing edge-on ram-pressure stripping with little star formation in the tail
Donahue, Megan; Combes, Françoise; Sun, Ming +11 more
Ram pressure stripping (RPS) is an important mechanism for galaxy evolution. In this work, we present results from HST and APEX observations of one RPS galaxy, ESO 137-002 in the closest rich cluster Abell 3627. The galaxy is known to host prominent X-ray and H α tails. The HST data reveal significant features indicative of RPS in the galaxy, incl…
Testing a scaling relation between coherent radio emission and physical parameters of hot magnetic stars
Wade, Gregg A.; Chandra, Poonam; Das, Barnali +4 more
Coherent radio emission via electron cyclotron maser emission (ECME) from hot magnetic stars was discovered more than two decades ago, but the physical conditions that make the generation of ECME favourable remain uncertain. Only recently was an empirical relation, connecting ECME luminosity with the stellar magnetic field and temperature, propose…
TOI-2119: a transiting brown dwarf orbiting an active M-dwarf from NASA's TESS mission
Latham, David W.; Stassun, Keivan G.; Collins, Karen A. +27 more
We report the discovery of TOI-2119b, a transiting brown dwarf (BD) that orbits and is completely eclipsed by an active M-dwarf star. Using light-curve data from the Transiting Exoplanet Survey Satellite mission and follow-up high-resolution Doppler spectroscopic observations, we find the BD has a radius of Rb = 1.08 ± 0.03RJ…
Charting galactic accelerations - II. How to 'learn' accelerations in the solar neighbourhood
Evans, N. W.; Naik, A. P.; An, J. +1 more
Gravitational acceleration fields can be deduced from the collisionless Boltzmann equation, once the distribution function is known. This can be constructed via the method of normalizing flows from data sets of the positions and velocities of stars. Here, we consider application of this technique to the solar neighbourhood. We construct mock data …
Four bright eclipsing binaries with γ Doradus pulsating components: CM Lac, MZ Lac, RX Dra, and V2077 Cyg
Van Reeth, Timothy; Southworth, John
The study of pulsating stars in eclipsing binaries holds the promise of combining two different ways of measuring the physical properties of a star to obtain improved constraints on stellar theory. Gravity (g) mode pulsations such as those found in γ Doradus stars can be used to probe rotational profiles, mixing, and magnetic fields. Until recentl…
Probing vainsthein-screening gravity with galaxy clusters using internal kinematics and strong and weak lensing
Umetsu, Keiichi; Pizzuti, Lorenzo; Saltas, Ippocratis D. +1 more
We use high-precision combined strong/weak lensing and kinematics measurements of the total mass profiles of the observed galaxy clusters MACS J1206.2-0847 and Abell S1063, to constrain the relativistic sector of the general DHOST dark energy theories, which exhibit a partial breaking of the so called Vainsthein screening mechanism, on the linear …
Constraints on the Galactic Centre environment from Gaia hypervelocity stars II: The evolved population
Rossi, E. M.; Marchetti, T.; Evans, F. A.
A dynamical encounter between a stellar binary and Sgr A* in the Galactic Centre (GC) can tidally separate the binary and eject one member with a velocity beyond the escape speed of the Milky Way. These hypervelocity stars (HVSs) can offer insight into the stellar populations in the GC environment. In a previous work, our simulations showed that t…
Multiwavelength properties of 850-µm selected sources from the North Ecliptic Pole SCUBA-2 survey
Goto, Tomotsugu; Kim, Seong Jin; Conselice, Christopher J. +25 more
We present the multiwavelength counterparts of 850-$\mu$m selected submillimetre sources over a 2-deg2 field centred on the North Ecliptic Pole. In order to overcome the large beam size (15 arcsec) of the 850-$\mu$m images, deep optical to near-infrared (NIR) photometric data and arcsecond-resolution 20-cm images are used to identify co…
Synthetic solar cycle for active regions violating the Hale's polarity law
Abramenko, V.; Sokoloff, D.; Zhukova, A. +1 more
Long observational series for bipolar active regions (ARs) provide significant information about the mutual transformation of the poloidal and toroidal components of the global solar magnetic field. The direction of the toroidal field determines the polarity of leading sunspots in ARs in accordance with the Hale's polarity law. The vast majority o…