Search Publications
Tight Correlations between Massive Galaxy Structural Properties and Dynamics: The Mass Fundamental Plane was in Place by z ~ 2
van Dokkum, Pieter G.; Franx, Marijn; Bezanson, Rachel +3 more
The fundamental plane (FP) is an empirical relation between the size, surface brightness, and velocity dispersion of early-type galaxies. This relation has been studied extensively for early-type galaxies in the local universe to constrain galaxy formation mechanisms. The evolution of the zero point of this plane has been extended to high redshift…
Detecting Nanoflare Heating Events in Subarcsecond Inter-moss Loops Using Hi-C
Golub, Leon; Winebarger, Amy R.; De Pontieu, Bart +10 more
The High-resolution Coronal Imager (Hi-C) flew aboard a NASA sounding rocket on 2012 July 11 and captured roughly 345 s of high-spatial and temporal resolution images of the solar corona in a narrowband 193 Å channel. In this paper, we analyze a set of rapidly evolving loops that appear in an inter-moss region. We select six loops that both appear…
A ~ 3.8 hr Periodicity from an Ultrasoft Active Galactic Nucleus Candidate
Lin, Dacheng; Godet, Olivier; Webb, Natalie A. +2 more
Very few galactic nuclei are found to show significant X-ray quasi-periodic oscillations (QPOs). After carefully modeling the noise continuum, we find that the ~3.8 hr QPO in the ultrasoft active galactic nucleus candidate 2XMM J123103.2+110648 was significantly detected (~5σ) in two XMM-Newton observations in 2005, but not in the one in 2003. The…
Unveiling a Population of Galaxies Harboring Low-mass Black Holes with X-Rays
Silverman, J. D.; Brandt, W. N.; Xue, Y. Q. +7 more
We report the discovery of three low-mass black hole (BH) candidates residing in the centers of low-mass galaxies at z < 0.3 in the Chandra Deep Field-South Survey. These BHs are initially identified as candidate active galactic nuclei based on their X-ray emission in deep Chandra observations. Multi-wavelength observations are used to strength…
The Mass-Metallicity Relation of a z ~ 2 Protocluster with MOSFIRE
Shapley, Alice E.; Steidel, Charles C.; Reddy, Naveen A. +7 more
We present Keck/MOSFIRE observations of the role of environment in the formation of galaxies at z ~ 2. Using K-band spectroscopy of Hα and [N II] emission lines, we have analyzed the metallicities of galaxies within and around a z = 2.3 protocluster discovered in the HS1700+643 field. Our main sample consists of 23 protocluster and 20 field galaxi…
Further Evidence for a Supermassive Black Hole Mass-Pitch Angle Relation
Bentz, Misty C.; Davis, Benjamin L.; Kennefick, Julia D. +7 more
We present new and stronger evidence for a previously reported relationship between galactic spiral arm pitch angle P (a measure of the tightness of spiral structure) and the mass M BH of a disk galaxy's nuclear supermassive black hole (SMBH). We use an improved method to accurately measure the spiral arm pitch angle in disk galaxies to…
SN 2009ip: Constraints on the Progenitor Mass-loss Rate
Lin, L.; Kouveliotou, C.; Kasliwal, M. M. +4 more
Some supernovae (SNe) show evidence for mass-loss events taking place prior to their explosions. Measuring their pre-outburst mass-loss rates provides essential information regarding the mechanisms that are responsible for these events. Here we present XMM-Newton and Swift X-ray observations taken after the latest, and presumably the final, outbur…
Metallicity Differences in Type Ia Supernova Progenitors Inferred from Ultraviolet Spectra
Foley, Ryan J.; Kirshner, Robert P.
Two "twin" Type Ia supernovae (SNe Ia), SNe 2011by and 2011fe, have extremely similar optical light-curve shapes, colors, and spectra, yet have different ultraviolet (UV) continua as measured in Hubble Space Telescope spectra and measurably different peak luminosities. We attribute the difference in the UV continua to significantly different proge…
SPT-CL J0205-5829: A z = 1.32 Evolved Massive Galaxy Cluster in the South Pole Telescope Sunyaev-Zel'dovich Effect Survey
Gladders, M. D.; Rest, A.; Foley, R. J. +80 more
The galaxy cluster SPT-CL J0205-5829 currently has the highest spectroscopically confirmed redshift, z = 1.322, in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. XMM-Newton observations measure a core-excluded temperature of TX = 8.7+1.0 -0.8 keV producing a mass estimate that is consistent with the S…
Innocent Bystanders: Carbon Stars from the Sloan Digital Sky Survey
Green, Paul
Among stars showing carbon molecular bands (C stars), the main-sequence dwarfs, likely in post-mass transfer binaries, are numerically dominant in the Galaxy. Via spectroscopic selection from the Sloan Digital Sky Survey, we retrieve 1220 high galactic latitude C stars, ~5 times more than previously known, including a wider variety than past techn…