Search Publications
The Origin of the Late-time Luminosity of Supernova 2011dh
Maund, Justyn R.
Due to the small amount of hydrogen (≤0.1 M ⊙) remaining on the surface of their progenitors, SNe IIb are sensitive probes of the mass-loss processes of massive stars toward the ends of their lives, including the role of binarity. We report late-time Hubble Space Telescope observations of SN 2011dh in M51, and a brief period of rebright…
Spectroscopic membership for the populous 300 Myr-old open cluster NGC 3532
Strassmeier, K. G.; Barnes, S. A.; James, D. J. +3 more
Context. NGC 3532 is an extremely rich open cluster embedded in the Galactic disc, hitherto lacking a comprehensive, documented membership list.
Aims: We provide membership probabilities from new radial velocity observations of solar-type and low-mass stars in NGC 3532, in part as a prelude to a subsequent study of stellar rotation in the clu…
A Trio of Massive Black Holes Caught in the Act of Merging
Shen, Yue; Nyland, Kristina; Li, Zhiyuan +6 more
We report the discovery of SDSS J0849+1114 as the first known triple Type 2 Seyfert nucleus. It represents three active black holes that are identified from new spatially resolved optical slit spectroscopy using the Dual Imaging Spectrograph on the 3.5 m telescope at the Apache Point Observatory. We also present new complementary observations incl…
Direct detection of quasar feedback via the Sunyaev-Zeldovich effect
Nyland, Kristina; Lacy, Mark; Surace, Jason +6 more
The nature and energetics of feedback from thermal winds in quasars can be constrained via observations of the Sunyaev-Zeldovich Effect (SZE) induced by the bubble of thermal plasma blown into the intergalactic medium by the quasar wind. In this letter, we present evidence that we have made the first detection of such a bubble, associated with the…
RELICS: High-resolution Constraints on the Inner Mass Distribution of the z = 0.83 Merging Cluster RXJ0152.7-1357 from Strong Lensing
Ouchi, Masami; Mahler, Guillaume; Bradač, Maruša +37 more
Strong gravitational lensing (SL) is a powerful means of mapping the distribution of dark matter. In this work, we perform an SL analysis of the prominent X-ray cluster RXJ0152.7-1357 (z = 0.83, also known as CL0152.7-1357) in Hubble Space Telescope images, taken in the framework of the Reionization Lensing Cluster Survey (RELICS). On top of a pre…
An Inner Disk in the Large Gap of the Transition Disk SR 24S
Benisty, Myriam; Pinilla, Paola; Harsono, Daniel +3 more
We report new Atacama Large Millimeter/submillimeter Array (ALMA) Band 3 observations at 2.75 mm of the transition disk around SR 24S, with an angular resolution of ∼0.″11 × 0.″09 and a peak signal-to-noise ratio of ∼24. We detect an inner disk and a mostly symmetric ring-like structure that peaks at ∼0.″32, which is ∼37 au at a distance of ∼114.4…
Discovery of weak magnetic fields in four DZ white dwarfs in the local 20 pc volume. Implications for the frequency of magnetic fields with cooling age
Bagnulo, S.; Landstreet, J. D.
We report the discovery of weak magnetic fields in three white dwarfs within the local 20 pc volume (WD 0816-310, WD 1009-184, and WD 1532+129), and we confirm the magnetic nature of a fourth star (WD 2138-332) in which we had previously detected a field at a 3σ level. The spectra of all these white dwarfs are characterised by the presence of meta…
The Extremely High Dark Matter Halo Concentration of the Relic Compact Elliptical Galaxy Mrk 1216
Barth, Aaron J.; Buote, David A.
Spatially compact stellar profiles and old stellar populations have established compact elliptical galaxies (CEGs) as local analogs of the high-redshift “red nuggets” thought to represent the progenitors of today’s early-type galaxies (ETGs). To address whether the structure of the dark matter (DM) halo in a CEG also reflects the extremely quiesce…
The Structure of the Orion Nebula in the Direction of θ 1 Ori C
Abel, N. P.; O'Dell, C. R.; Ferland, G. J.
We have used existing optical emission and absorption lines, [C II] emission lines, and H I absorption lines to create a new model for a central column of material near the Trapezium region of the Orion Nebula. This was necessary because recent high spectral resolution spectra of optical emission lines and imaging spectra in the [C II] 158 µ…
A radio halo surrounding the Brightest Cluster Galaxy in RXCJ0232.2-4420: a mini-halo in transition?
Kale, Ruta; Parekh, Viral; Shende, Krishna M.
Diffuse radio sources associated with the intra-cluster medium are direct probes of the cosmic ray electrons and magnetic fields. We report the discovery of a diffuse radio source in the galaxy cluster RXCJ0232.2-4420 (SPT-CL J0232-4421, z = 0.2836) using 606 MHz observations with the Giant Metrewave Radio Telescope. The diffuse radio source surro…