Search Publications
Ultra-diffuse and Ultra-compact Galaxies in the Frontier Fields Cluster Abell 2744
van Dokkum, Pieter; Romanowsky, Aaron J.; Abraham, Roberto +3 more
We report the discovery of a large population of ultra-diffuse galaxies (UDGs) in the massive galaxy cluster Abell 2744 (z = 0.308) as observed by the Hubble Frontier Fields program. Since this cluster is ∼5 times more massive than Coma, our observations allow us to extend 0.7 dex beyond the high-mass end of the relationship between UDG abundance …
Globular Cluster Systems in Brightest Cluster Galaxies. III: Beyond Bimodality
Bailin, Jeremy; Rothberg, Barry; Harris, William E. +4 more
We present new deep photometry of the rich globular cluster (GC) systems around the Brightest Cluster Galaxies UGC 9799 (Abell 2052) and UGC 10143 (Abell 2147), obtained with the Hubble Space Telescope (HST) ACS and WFC3 cameras. For comparison, we also present new reductions of similar HST/ACS data for the Coma supergiants NGC 4874 and 4889. All …
The Grism Lens-amplified Survey from Space (GLASS). X. Sub-kiloparsec Resolution Gas-phase Metallicity Maps at Cosmic Noon behind the Hubble Frontier Fields Cluster MACS1149.6+2223
Fontana, Adriano; Schmidt, Kasper B.; Treu, Tommaso +17 more
We combine deep Hubble Space Telescope grism spectroscopy with a new Bayesian method to derive maps of gas-phase metallicity for 10 star-forming galaxies at high redshift (1.2≲ z≲ 2.3). Exploiting lensing magnification by the foreground cluster MACS1149.6+2223, we reach sub-kiloparsec spatial resolution and push the limit of stellar mass associate…
A Massive Shell of Supernova-formed Dust in SNR G54.1+0.3
Gelfand, Joseph D.; Temim, Tea; Reynolds, Stephen P. +5 more
While theoretical models of dust condensation predict that most refractory elements produced in core-collapse supernovae (SNe) efficiently condense into dust, a large quantity of dust has so far only been observed in SN 1987A. We present an analysis of observations from the Spitzer Space Telescope, Herschel Space Observatory, Stratospheric Observa…
Dust-trapping Vortices and a Potentially Planet-triggered Spiral Wake in the Pre-transitional Disk of V1247 Orionis
Monnier, John D.; Kraus, Stefan; Wisniewski, John +9 more
The radial drift problem constitutes one of the most fundamental problems in planet formation theory, as it predicts particles to drift into the star before they are able to grow to planetesimal size. Dust-trapping vortices have been proposed as a possible solution to this problem, as they might be able to trap particles over millions of years, al…
X-Rays from the Location of the Double-humped Transient ASASSN-15lh
Sbarufatti, B.; Berger, E.; Dall'Osso, S. +13 more
We present the detection of persistent soft X-ray radiation with {L}x∼ {10}41-1042 erg s-1 at the location of the extremely luminous, double-humped transient ASASSN-15lh as revealed by Chandra and Swift. We interpret this finding in the context of observations from our multiwavelength campaign, which rev…
CMB Polarization B-mode Delensing with SPTpol and Herschel
Bock, J. J.; Chiang, H. C.; Conley, A. +60 more
We present a demonstration of delensing the observed cosmic microwave background (CMB) B-mode polarization anisotropy. This process of reducing the gravitational-lensing-generated B-mode component will become increasingly important for improving searches for the B modes produced by primordial gravitational waves. In this work, we delens B-mode map…
iPTF 16asu: A Luminous, Rapidly Evolving, and High-velocity Supernova
Cenko, S. B.; Sollerman, J.; Hurley, K. +23 more
Wide-field surveys are discovering a growing number of rare transients whose physical origin is not yet well understood. Here we present optical and UV data and analysis of intermediate Palomar Transient Factory (iPTF) 16asu, a luminous, rapidly evolving, high-velocity, stripped-envelope supernova (SN). With a rest-frame rise time of just four day…
Observational Signatures of Transverse Magnetohydrodynamic Waves and Associated Dynamic Instabilities in Coronal Flux Tubes
Yokoyama, T.; Antolin, P.; De Moortel, I. +1 more
Magnetohydrodynamic (MHD) waves permeate the solar atmosphere and constitute potential coronal heating agents. Yet, the waves detected so far may be but a small subset of the true existing wave power. Detection is limited by instrumental constraints but also by wave processes that localize the wave power in undetectable spatial scales. In this stu…
How Do Stars Gain Their Mass? A JCMT/SCUBA-2 Transient Survey of Protostars in Nearby Star-forming Regions
Herczeg, Gregory J.; Kwon, Woojin; Soam, Archana +55 more
Most protostars have luminosities that are fainter than expected from steady accretion over the protostellar lifetime. The solution to this problem may lie in episodic mass accretion—prolonged periods of very low accretion punctuated by short bursts of rapid accretion. However, the timescale and amplitude for variability at the protostellar phase …