Search Publications
What does CIVλ1549 tell us about the physical driver of the Eigenvector quasar sequence?
Marziani, P.; Stirpe, G. M.; Perea, J. +8 more
Broad emission lines in quasars enable us to "resolve" structure and kinematics of the broad-line emitting region (BLR) thought to involve an accretion disk feeding a supermassive black hole. Interpretation of broad line measures within the 4DE1 formalism simplifies the apparent confusion among such data by contrasting and unifying properties of s…
Discovery of a Kiloparsec Extended Hard X-Ray Continuum and Fe-Kα from the Compton Thick AGN ESO 428-G014
Elvis, M.; Fabbiano, G.; Raymond, J. +5 more
We report the discovery of kiloparsec-scale diffuse emission in both the hard continuum (3-6 keV) and in the Fe-Kα line in the Compton thick (CT) Seyfert galaxy ESO 428-G014. This extended hard component contains at least ∼24% of the observed 3-8 keV emission, and follows the direction of the extended optical line emission (ionization cone) and ra…
Predicting the Presence of Companions for Stripped-envelope Supernovae: The Case of the Broad-lined Type Ic SN 2002ap
Fox, O. D.; Smith, N.; Filippenko, A. V. +10 more
Many young, massive stars are found in close binaries. Using population synthesis simulations we predict the likelihood of a companion star being present when these massive stars end their lives as core-collapse supernovae (SNe). We focus on stripped-envelope SNe, whose progenitors have lost their outer hydrogen and possibly helium layers before e…
Constraints on primordial magnetic fields from Planck data combined with the South Pole Telescope CMB B -mode polarization measurements
Li, Yun; Pogosian, Levon; Zucca, Alex
A primordial magnetic field (PMF) present before recombination can leave specific signatures on the cosmic microwave background (CMB) fluctuations. Of particular importance is its contribution to the B-mode polarization power spectrum. Indeed, vortical modes sourced by the PMF can dominate the B-mode power spectrum on small scales, as they survive…
Electron and Ion Dynamics of the Solar Wind Interaction with a Weakly Outgassing Comet
Henri, Pierre; Divin, Andrey; Deca, Jan +4 more
Using a 3D fully kinetic approach, we disentangle and explain the ion and electron dynamics of the solar wind interaction with a weakly outgassing comet. We show that, to first order, the dynamical interaction is representative of a four-fluid coupled system. We self-consistently simulate and identify the origin of the warm and suprathermal electr…
Diagnosing collisionless energy transfer using field-particle correlations: gyrokinetic turbulence
Klein, Kristopher G.; Howes, Gregory G.; Tenbarge, Jason M.
Determining the physical mechanisms that extract energy from turbulent fluctuations in weakly collisional magnetized plasmas is necessary for a more complete characterization of the behaviour of a variety of space and astrophysical plasmas. Such a determination is complicated by the complex nature of the turbulence as well as observational constra…
Bose-Einstein-condensed scalar field dark matter and the gravitational wave background from inflation: New cosmological constraints and its detectability by LIGO
Shapiro, Paul R.; Li, Bohua; Rindler-Daller, Tanja
We consider an alternative to weakly interacting massive particle (WIMP) cold dark matter (CDM)—ultralight bosonic dark matter (m ≳10-22 eV /c2) described by a complex scalar field (SFDM) with a global U (1 ) symmetry—for which the comoving particle number density or charge density is conserved after particle production durin…
Whimper of a Bang: Documenting the Final Days of the Nearby Type Ia Supernova 2011fe
Garnavich, P. M.; Kochanek, C. S.; Stanek, K. Z. +1 more
Using the Hubble Space Telescope (HST) and the Large Binocular Telescope, we followed the evolution of the Type Ia supernova (SN Ia) 2011fe for an unprecedented 1840 days past B-band maximum light and over a factor of 7 million in flux. At 1840 days, the 4000-17000 Å quasi-bolometric luminosity is just (420+/- 20) {L}⊙ . By measuring th…
Estimation of a coronal mass ejection magnetic field strength using radio observations of gyrosynchrotron radiation
Carley, Eoin P.; Vilmer, Nicole; Simões, Paulo J. A. +1 more
Coronal mass ejections (CMEs) are large eruptions of plasma and magnetic field from the low solar corona into interplanetary space. These eruptions are often associated with the acceleration of energetic electrons which produce various sources of high intensity plasma emission. In relatively rare cases, the energetic electrons may also produce gyr…
A Comparison of Cosmological Parameters Determined from CMB Temperature Power Spectra from the South Pole Telescope and the Planck Satellite
Bleem, L. E.; Stark, A. A.; George, E. M. +42 more
The Planck cosmic microwave background temperature data are best fit with a ΛCDM model that mildly contradicts constraints from other cosmological probes. The South Pole Telescope (SPT) 2540 {\deg }2 SPT-SZ survey offers measurements on sub-degree angular scales (multipoles 650≤slant {\ell }≤slant 2500) with sufficient precision to use …