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An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy
Multiwavelength observations of a unique γ-ray–selected transient detected by the Swift satellite, accompanied by bright emission across the electromagnetic spectrum, and whose properties are unlike any previously observed source are presented. Expand
Motivated by a new wave of kinematical tracers in the outer regions of early-type galaxies (ellipticals and lenticulars), we re-examine the role of angular momentum in galaxies of all types. WeExpand
Spectroscopic Confirmation of the Existence of Large, Diffuse Galaxies in the Coma Cluster
We recently identified a population of low surface brightness objects in the field of the z=0.023 Coma cluster, using the Dragonfly Telephoto Array. Here we present Keck spectroscopy of one of theExpand
A Dearth of Dark Matter in Ordinary Elliptical Galaxies
The kinematics of the outer parts of three intermediate-luminosity elliptical galaxies were studied with the Planetary Nebula Spectrograph. The galaxies' velocity-dispersion profiles were found toExpand
A High Stellar Velocity Dispersion and ~100 Globular Clusters for the Ultra Diffuse Galaxy Dragonfly 44
Recently a population of large, very low surface brightness, spheroidal galaxies was identified in the Coma cluster. The apparent survival of these Ultra Diffuse Galaxies (UDGs) in a rich clusterExpand
The Stellar Initial Mass Function in Early-Type Galaxies from Absorption Line Spectroscopy. III. Radial Gradients
There is good evidence that the centers of massive early-type galaxies have a bottom-heavy stellar initial mass function (IMF) compared to the IMF of the Milky Way. Here we study the radial variationExpand
We present the most extensive combined photometric and spectroscopic study to date of the enormous globular cluster (GC) system around M87, the central giant elliptical galaxy in the nearby VirgoExpand
An overmassive Dark Halo around an Ultra-diffuse Galaxy in the Virgo Cluster
Ultra diffuse galaxies (UDGs) have the sizes of giant galaxies but the luminosities of dwarfs. A key to understanding their origins comes from their total masses, but their low surface brightnessesExpand
A deep kinematic survey of planetary nebulae in the Andromeda Galaxy
This thesis presents a survey of compact emission-line objects in the Andromeda Galaxy (M31), performed using a novel new instrument, the Planetary Nebula Spectrograph. The final catalogue containsExpand
Angular Momentum and Galaxy Formation Revisited: Effects of Variable Mass-to-light Ratios
We rederive the relation between the specific angular momentum}. and the mass M. of the stellar matter in galaxies of different morphological types. Thi s is a revision of the j.- M. di agramExpand