Search Publications
The Influence of Spatial resolution on Nonlinear Force-free Modeling
Sun, X.; Schrijver, C. J.; Canou, A. +11 more
The nonlinear force-free field (NLFFF) model is often used to describe the solar coronal magnetic field, however a series of earlier studies revealed difficulties in the numerical solution of the model in application to photospheric boundary data. We investigate the sensitivity of the modeling to the spatial resolution of the boundary data, by app…
Supernova 1987A: a Template to Link Supernovae to Their Remnants
Miceli, M.; Bocchino, F.; Orlando, S. +1 more
The emission of supernova remnants (SNRs) reflects the properties of both the progenitor supernovae (SNe) and the surrounding environment. The complex morphology of the remnants, however, hampers the disentanglement of the two contributions. Here, we aim at identifying the imprint of SN 1987A on the X-ray emission of its remnant and at constrainin…
IRIS Si IV Line Profiles: An Indication for the Plasmoid Instability during Small-scale Magnetic Reconnection on the Sun
Innes, D. E.; Huang, Y. -M.; Guo, L. -J. +1 more
Our understanding of the process of fast reconnection has undergone a dramatic change in the last 10 years driven, in part, by the availability of high-resolution numerical simulations that have consistently demonstrated the break-up of current sheets into magnetic islands, with reconnection rates that become independent of Lundquist number, chall…
A Multiwavelength Study of the Relativistic Tidal Disruption Candidate Swift J2058.4+0516 at Late Times
Fruchter, Andrew S.; Filippenko, Alexei V.; Cenko, S. Bradley +12 more
We report a multiwavelength (X-ray, ultraviolet/optical/infrared (UVOIR), radio) analysis of the relativistic tidal disruption event (TDE) candidate Sw J2058+05 from 3 months to 3 yr post-discovery in order to study its properties and compare its behavior with that of Sw J1644+57. Our main results are as follows: (1) The long-term X-ray light curv…
The Metagalactic Ionizing Background: A Crisis in UV Photon Production or Incorrect Galaxy Escape Fractions?
Shull, J. Michael; Danforth, Charles W.; Tilton, Evan M. +1 more
Recent suggestions of a “photon underproduction crisis” have generated concern over the intensity and spectrum of ionizing photons in the metagalactic ultraviolet background (UVB). The balance of hydrogen photoionization and recombination determines the opacity of the low-redshift intergalactic medium (IGM). We calibrate the hydrogen photoionizati…
Storm in a "Teacup": A Radio-quiet Quasar with ≈10 kpc Radio-emitting Bubbles and Extreme Gas Kinematics
Thomson, A. P.; Alexander, D. M.; Bauer, F. E. +5 more
We present multi-frequency (1-8 GHz) Very Large Array data, combined with VIsible MultiObject Spectrograph integral field unit data and Hubble Space Telescope imaging, of a z = 0.085 radio-quiet type 2 quasar (with L 1.4 GHz ≈ 5 × 1023 W Hz-1 and L AGN ≈ 2 × 1045 erg s-1). Due to th…
An Extreme Metallicity, Large-scale Outflow from a Star-forming Galaxy at z ~ 0.4
Charlton, Jane C.; Kacprzak, Glenn G.; Churchill, Christopher W. +4 more
We present a detailed analysis of a large-scale galactic outflow in the circumgalactic medium of a massive ({M}{{h}}∼ {10}12.5 {M}⊙ ), star-forming (∼ 6.9 {M}⊙ yr-1), sub-L* (∼ 0.5{L}B*) galaxy at z = 0.39853 that exhibits a wealth of metal-line absorption in …
Cross-correlation between the CMB Lensing Potential Measured by Planck and High-z Submillimeter Galaxies Detected by the Herschel-Atlas Survey
Baccigalupi, C.; Bielewicz, P.; Danese, L. +15 more
We present the first measurement of the correlation between the map of the cosmic microwave background (CMB) lensing potential derived from the Planck nominal mission data and z≳ 1.5 galaxies detected by the Herschel-ATLAS (H-ATLAS) survey covering about 600 {{deg }2}, i.e., about 1.4% of the sky. We reject the hypothesis that there is …
The Peculiar Behavior of Halo Coronal Mass Ejections in Solar Cycle 24
Gopalswamy, N.; Michalek, G.; Yashiro, S. +3 more
We report on the remarkable finding that the halo coronal mass ejections (CMEs) in cycle 24 are more abundant than in cycle 23, although the sunspot number in cycle 24 has dropped by ∼40%. We also find that the distribution of halo-CME source locations is different in cycle 24: the longitude distribution of halos is much flatter with the number of…
GHIGLS: H I Mapping at Intermediate Galactic Latitude Using the Green Bank Telescope
Miville-Deschênes, M. -A.; Martin, P. G.; Blagrave, K. P. M. +5 more
This paper introduces and describes the data cubes from GHIGLS, deep Green Bank Telescope (GBT) surveys of the 21 cm line emission of H i in 37 targeted fields at intermediate Galactic latitude. The GHIGLS fields together cover over 1000 deg2 at 9\buildrel{ \prime}\over{.} 55 spatial resolution. The H i spectra have an effective velocit…