Search Publications
Missions
Journals
Publication Years
Discovery of Molecular Gas around HD 131835 in an APEX Molecular Line Survey of Bright Debris Disks
Pascucci, I.; Ábrahám, P.; Kóspál, Á. +11 more
Debris disks are considered to be gas-poor, but recent observations revealed molecular or atomic gas in several 10-40 Myr old systems. We used the APEX and IRAM 30 m radio telescopes to search for CO gas in 20 bright debris disks. In one case, around the 16 Myr old A-type star HD 131835, we discovered a new gas-bearing debris disk, where the CO 3-…
Red Supergiants as Cosmic Abundance Probes: The Sculptor Galaxy NGC 300
Bender, Ralf; Bonanos, Alceste Z.; Bresolin, Fabio +9 more
We present a quantitative spectroscopic study of 27 red supergiants (RSGs) in the Sculptor Galaxy NGC 300. J-band spectra were obtained using KMOS on the Very Large Telescope and studied with state of the art synthetic spectra including NLTE corrections for the strongest diagnostic lines. We report a central metallicity of [Z] = -0.03 ± 0.05 with …
Persistent aeolian activity at Endeavour crater, Meridiani Planum, Mars; new observations from orbit and the surface
Johnson, Jeffrey R.; Chojnacki, Matthew; Moersch, Jeffrey E. +3 more
Aeolian-driven bedform activity is now known to occur in many regions of Mars, based on surface and orbital observation of contemporary martian ripple and dune mobility events. Many of these sites have only been monitored with sufficient resolution data for the last few Mars years, when the High Resolution Imaging Science Experiment (HiRISE) began…
Data-driven modeling of the solar wind from 1 Rs to 1 AU
Feng, Xueshang; Xiang, Changqing; Ma, Xiaopeng
We present here a time-dependent three-dimensional magnetohydrodynamic (MHD) solar wind simulation from the solar surface to the Earth's orbit driven by time-varying line-of-sight solar magnetic field data. The simulation is based on the three-dimensional (3-D) solar-interplanetary (SIP) adaptive mesh refinement (AMR) space-time conservation eleme…
Observations of Binary Stars with the Differential Speckle Survey Instrument. VI. Measures during 2014 at the Discovery Channel Telescope
van Belle, Gerard T.; Everett, Mark E.; Bjorkman, Karen S. +3 more
We present the results of 938 speckle measures of double stars and suspected double stars drawn mainly from the Hipparcos Catalog, as well as 208 observations where no companion was noted. One hundred fourteen pairs have been resolved for the first time. The data were obtained during four observing runs in 2014 using the Differential Speckle Surve…
A computational and theoretical investigation of nonlinear wave-particle interactions in oblique whistlers
Omura, Yoshiharu; Nunn, David
Most previous work on nonlinear wave-particle interactions between energetic electrons and VLF waves in the Earth's magnetosphere has assumed parallel propagation, the underlying mechanism being nonlinear trapping of cyclotron resonant electrons in a parabolic magnetic field inhomogeneity. Here nonlinear wave-particle interaction in oblique whistl…
A Probable Milli-parsec Supermassive Binary Black Hole in the Nearest Quasar Mrk 231
Lu, Youjun; Yan, Chang-Shuo; Dai, Xinyu +1 more
Supermassive binary black holes (BBHs) are unavoidable products of galaxy mergers and are expected to exist in the cores of many quasars. Great effort has been made during the past several decades to search for BBHs among quasars; however, observational evidence for BBHs remains elusive and ambiguous, which is difficult to reconcile with theoretic…
Measurements of E-Mode Polarization and Temperature-E-Mode Correlation in the Cosmic Microwave Background from 100 Square Degrees of SPTpol Data
Ade, P. A. R.; Chiang, H. C.; Hanson, D. +63 more
We present measurements of E-mode polarization and temperature-E-mode correlation in the cosmic microwave background using data from the first season of observations with SPTpol, the polarization-sensitive receiver currently installed on the South Pole Telescope (SPT). The observations used in this work cover 100 {{deg }2} of sky with a…
An XMM-Newton view of FeKα in high-mass X-ray binaries
Eikmann, W.; Oskinova, L. M.; Torrejón, J. M. +4 more
We present a comprehensive analysis of the whole sample of available XMM-Newton observations of high-mass X-ray binaries (HMXBs) until August 2013, focusing on the FeKα emission line. This line is key to better understanding the physical properties of the material surrounding the X-ray source within a few stellar radii (the circumstellar medium). …
The Fast Filament Eruption Leading to the X-flare on 2014 March 29
Krucker, Säm; Young, Peter R.; Kleint, Lucia +3 more
We investigate the sequence of events leading to the solar X1 flare SOL2014-03-29T17:48. Because of the unprecedented joint observations of an X-flare with the ground-based Dunn Solar Telescope and the spacecraft IRIS, Hinode, RHESSI, STEREO, and the Solar Dynamics Observatory, we can sample many solar layers from the photosphere to the corona. A …