Search Publications
The Assembly of Milky-Way-like Galaxies Since z ~ 2.5
van Dokkum, Pieter G.; Franx, Marijn; Labbé, Ivo +16 more
Galaxies with the mass of the Milky Way dominate the stellar mass density of the universe but it is uncertain how and when they were assembled. Here we study progenitors of these galaxies out to z = 2.5, using data from the 3D-HST and CANDELS Treasury surveys. We find that galaxies with present-day stellar masses of log (M) ≈ 10.7 built ~90% of th…
Compositional Diversity in the Atmospheres of Hot Neptunes, with Application to GJ 436b
Fortney, J. J.; Moses, J. I.; Madhusudhan, N. +6 more
Neptune-sized extrasolar planets that orbit relatively close to their host stars—often called "hot Neptunes"—are common within the known population of exoplanets and planetary candidates. Similar to our own Uranus and Neptune, inefficient accretion of nebular gas is expected produce hot Neptunes whose masses are dominated by elements heavier than …
Dust Extinction from Balmer Decrements of Star-forming Galaxies at 0.75 <= z <= 1.5 with Hubble Space Telescope/Wide-Field-Camera 3 Spectroscopy from the WFC3 Infrared Spectroscopic Parallel Survey
Scarlata, C.; Malkan, M.; Hathi, N. P. +14 more
Spectroscopic observations of Hα and Hβ emission lines of 128 star-forming galaxies in the redshift range 0.75 <= z <= 1.5 are presented. These data were taken with slitless spectroscopy using the G102 and G141 grisms of the Wide-Field-Camera 3 (WFC3) on board the Hubble Space Telescope as part of the WFC3 Infrared Spectroscopic Parallel sur…
A CANDELS-3D-HST synergy: Resolved Star Formation Patterns at 0.7 < z < 1.5
Ferguson, Henry C.; Grogin, Norman A.; Kocevski, Dale D. +20 more
We analyze the resolved stellar populations of 473 massive star-forming galaxies at 0.7 < z < 1.5, with multi-wavelength broadband imaging from CANDELS and Hα surface brightness profiles at the same kiloparsec resolution from 3D-HST. Together, this unique data set sheds light on how the assembled stellar mass is distributed within galaxies, …
Energetic electron acceleration by unsteady magnetic reconnection
André, M.; Vaivads, A.; Khotyaintsev, Yu. V. +2 more
Magnetic reconnection in the Earth's magnetosphere accelerates electrons. And yet energetic electrons are not created during reconnection in the solar wind. Observations from the Cluster spacecraft now suggest that electron acceleration is caused by repeated bursts of plasma flow, which only occur in situations where the magnetic reconnection is u…
The PdBI Arcsecond Whirlpool Survey (PAWS). I. A Cloud-scale/Multi-wavelength View of the Interstellar Medium in a Grand-design Spiral Galaxy
Leroy, Adam K.; Meidt, Sharon E.; Hughes, Annie +10 more
The Plateau de Bure Interferometer Arcsecond Whirlpool Survey has mapped the molecular gas in the central ~9 kpc of M51 in its 12CO(1-0) line emission at a cloud-scale resolution of ~40 pc using both IRAM telescopes. We utilize this data set to quantitatively characterize the relation of molecular gas (or CO emission) to other tracers o…
Validation of the Equilibrium Model for Galaxy Evolution to z ~ 3 through Molecular Gas and Dust Observations of Lensed Star-forming Galaxies
Saintonge, Amélie; Berta, Stefano; Wuyts, Stijn +11 more
We combine IRAM Plateau de Bure Interferometer and Herschel PACS and SPIRE measurements to study the dust and gas contents of high-redshift star-forming galaxies. We present new observations for a sample of 17 lensed galaxies at z = 1.4-3.1, which allow us to directly probe the cold interstellar medium of normal star-forming galaxies with stellar …
Determining Inclinations of Active Galactic Nuclei via their Narrow-line Region Kinematics. I. Observational Results
Kraemer, S. B.; Crenshaw, D. M.; Schmitt, H. R. +1 more
Active galactic nuclei (AGNs) are axisymmetric systems to first order; their observed properties are likely strong functions of inclination with respect to our line of sight (LOS). However, except for a few special cases, the specific inclinations of individual AGNs are unknown. We have developed a promising technique for determining the inclinati…
TPZ: photometric redshift PDFs and ancillary information by using prediction trees and random forests
Brunner, Robert J.; Carrasco Kind, Matias
With the growth of large photometric surveys, accurately estimating photometric redshifts, preferably as a probability density function (PDF), and fully understanding the implicit systematic uncertainties in this process, has become increasingly important. In this paper, we present a new, publicly available, parallel, machine learning algorithm th…
Direct Imaging of a Cold Jovian Exoplanet in Orbit around the Sun-like Star GJ 504
Kuzuhara, M.; Tamura, M.; Ishii, M. +54 more
Several exoplanets have recently been imaged at wide separations of >10 AU from their parent stars. These span a limited range of ages (<50 Myr) and atmospheric properties, with temperatures of 800-1800 K and very red colors (J - H > 0.5 mag), implying thick cloud covers. Furthermore, substantial model uncertainties exist at these young a…