Search Publications
Inferring Binary and Trinary Stellar Populations in Photometric and Astrometric Surveys
Leistedt, Boris; Hogg, David W.; Widmark, Axel
Multiple stellar systems are ubiquitous in the Milky Way but are often unresolved and seen as single objects in spectroscopic, photometric, and astrometric surveys. However, modeling them is essential for developing a full understanding of large surveys such as Gaia and connecting them to stellar and Galactic models. In this paper, we address this…
The Detached Auroras Induced by the Solar Wind Pressure Enhancement in Both Hemispheres From Imaging and In Situ Particle Observations
Zhou, Su; Luan, Xiaoli; Søraas, Finn +2 more
This paper presents simultaneous detached proton auroras that appeared in both hemispheres at 11:06 UT, 08 March 2012, just 2 min after a sudden solar wind pressure enhancement ( 11:04 UT) hit the Earth. They were observed under northward interplanetary magnetic field Bz condition and during the recovery phase of a moderate geomagnetic storm. In t…
The fast transient sky with Gaia
Jonker, Peter G.; van Leeuwen, Floor; Hodgkin, Simon T. +8 more
The ESA Gaia satellite scans the whole sky with a temporal sampling ranging from seconds and hours to months. Each time a source passes within the Gaia field of view, it moves over 10 charge coupled devices (CCDs) in 45 s and a light curve with 4.5 s sampling (the crossing time per CCD) is registered. Given that the 4.5 s sampling represents a vir…
Evolution of the Auroral Signatures of Jupiter's Magnetospheric Injections
Roussos, E.; Paranicas, C.; Bonfond, B. +3 more
Auroral emissions equatorward of the main emission at Jupiter are suggested to reflect the dynamics of the plasma in the middle magnetosphere. Here we examine the motion of the auroral signatures of magnetospheric injections appearing in Hubble Space Telescope (HST) images. Our results suggest that the injected plasma moves planetward and lags beh…
Reverse Current Model for Coronal Mass Ejection Cavity Formation
Li, Hui; Haw, Magnus A.; Wongwaitayakornkul, Pakorn +1 more
We report here a new model for explaining the three-part structure of coronal mass ejections (CMEs). The model proposes that the cavity in a CME forms because a rising electric current in the core prominence induces an oppositely directed electric current in the background plasma; this eddy current is required to satisfy the frozen-in magnetic flu…
Is Kasei Valles (Mars) the largest volcanic channel in the solar system?
Leverington, David W.
With a length of more than 2000 km and widths of up to several hundred kilometers, Kasei Valles is the largest outflow system on Mars. Superficially, the scabland-like character of Kasei Valles is evocative of terrestrial systems carved by catastrophic aqueous floods, and the system is widely interpreted as a product of outbursts from aquifers. Ho…
Coloring Jupiter's clouds: Radiolysis of ammonium hydrosulfide (NH4SH)
Hudson, Reggie L.; Loeffler, Mark J.
Here we present our recent studies on the color and spectral reflectance changes induced by ∼0.9 MeV proton irradiation of ammonium hydrosulfide, NH4SH, a compound predicted to be an important tropospheric cloud component of Jupiter and other giant planets. Ultraviolet-visible spectroscopy was used to observe and identify reaction produ…
Further constraints on neutron star crustal properties in the low-mass X-ray binary 1RXS J180408.9-342058
Degenaar, N.; Wijnands, R.; Parikh, A. S. +2 more
We report on two new quiescent XMM-Newton observations (in addition to the earlier Swift/XRT and XMM-Newton coverage) of the cooling neutron star crust in the low-mass X-ray binary 1RXS J180408.9-342058. Its crust was heated during the ∼4.5 month accretion outburst of the source. From our quiescent observations, fitting the spectra with a neutron …
Tidal Interactions and Mergers in Intermediate-redshift EDisCS Clusters
Moustakas, John; Aragón-Salamanca, Alfonso; Lotz, Jennifer M. +6 more
We study the fraction of tidal interactions and mergers (TIMs) with well-identified observability timescales (f TIM) in group, cluster, and accompanying field galaxies and its dependence on redshift (z), cluster velocity dispersion (σ), and environment analyzing Hubble Space Telescope/ACS images and catalogs from the ESO Distant Cluster…
Statistics of the polarized submillimetre emission maps from thermal dust in the turbulent, magnetized, diffuse ISM
Boulanger, F.; Falgarone, E.; Ghosh, T. +4 more
Context. The interstellar medium (ISM) is now widely acknowledged to display features ascribable to magnetized turbulence. With the public release of Planck data and the current balloon-borne and ground-based experiments, the growing amount of data tracing the polarized thermal emission from Galactic dust in the submillimetre provides choice diagn…