Search Publications
HST/STIS Ultraviolet Spectroscopy of the Components of the Massive Triple Star δ Ori A
Corcoran, Michael F.; Gies, Douglas R.; Moffat, Anthony F. J. +4 more
The multiple star system of δ Orionis is one of the closest examples of a system containing a luminous O-type, bright giant star (component Aa1). It is often used as a spectral-type standard and has the highest observed X-ray flux of any hot-star binary. The main component Aa1 is orbited by two lower mass stars, faint Aa2 in a 5.7 day eclipsing bi…
Are the Bulk of z > 2 Herschel Galaxies Proto-Spheroids?
Pozzi, F.; Gruppioni, C.; Cresci, G. +6 more
We present a backward approach for the interpretation of the evolution of the near-IR and the far-IR luminosity functions (LFs) across the redshift range 0\lt z\lt 3. In our method, late-type galaxies are treated by means of a parametric phenomenological method based on PEP/HerMES data up to z ∼ 4, whereas spheroids are described by means of a phy…
Latitudinal and Energy Dependence of Energetic Neutral Atom Spectral Indices Measured by the Interstellar Boundary Explorer
McComas, D. J.; Fuselier, S. A.; Schwadron, N. A. +8 more
We investigate the latitudinal and energy dependence of the globally distributed 0.5-6 keV energetic neutral atom (ENA) spectra measured by the Interstellar Boundary Explorer (IBEX) during the first 3 yrs of the mission. Our results are: (1) the ENA spectral indices at the two lowest energies (0.89 and 1.47 keV) exhibit no clear trend with eclipti…
Energetic Particle Pressure at Interplanetary Shocks: STEREO-A Observations
Lario, D.; Roelof, E. C.; Decker, R. B. +1 more
We study periods of elevated energetic particle intensities observed by STEREO-A when the partial pressure exerted by energetic (≥83 keV) protons (PEP) is larger than the pressure exerted by the interplanetary magnetic field (PB). In the majority of cases, these periods are associated with the passage of interplanetary shocks…
Dust and Polycyclic Aromatic Hydrocarbon in the HD 34700 Debris Disk
Seok, Ji Yeon; Li, Aigen
The debris disk around the Vega-type star HD 34700 is detected in dust thermal emission from the near-infrared (IR) to millimeter (mm) and submm wavelength range. Also detected is a distinct set of emission features at 3.3, 6.2, 7.7, 8.6, 11.3, and 12.7 µ {{m}}, which are commonly attributed to polycyclic aromatic hydrocarbon (PAH) molecules…
Extinction and Nebular Line Properties of a Herschel-selected Lensed Dusty Starburst at z = 1.027
Ivison, R. J.; Baes, Maarten; Fu, Hai +17 more
We present Hubble Space Telescope Wide Field Camera 3 (WFC3) imaging and grism spectroscopy observations of the Herschel-selected gravitationally lensed starburst galaxy HATLASJ1429-0028. The lensing system consists of an edge-on foreground disk galaxy at z = 0.218 with a nearly complete Einstein ring of the infrared luminous galaxy at z = 1.027. …
Statistics of the Velocity Gradient Tensor in Space Plasma Turbulent Flows
Consolini, Giuseppe; Materassi, Massimo; Federica Marcucci, Maria +1 more
In the last decade, significant advances have been presented for the theoretical characterization and experimental techniques used to measure and model all of the components of the velocity gradient tensor in the framework of fluid turbulence. Here, we attempt the evaluation of the small-scale velocity gradient tensor for a case study of space pla…
2D MHD and 1D HD Models of a Solar Flare—a Comprehensive Comparison of the Results
Srivastava, A. K.; Murawski, K.; Falewicz, R. +1 more
Without any doubt, solar flaring loops possess a multithread internal structure that is poorly resolved, and there are no means to observe heating episodes and thermodynamic evolution of the individual threads. These limitations cause fundamental problems in numerical modeling of flaring loops, such as selection of a structure and a number of thre…
Suzaku Observation of the Fermi Cygnus Cocoon: The Search for a Signature of Young Cosmic-Ray Electrons
Mizuno, T.; Takahashi, H.; Tibaldo, L. +4 more
The origin of Galactic cosmic rays remains unconfirmed, but promising candidates for their sources are found in star-forming regions. We report a series of X-ray observations, with Suzaku, toward the nearby star-forming region of Cygnus X. They aim at comparing diffuse X-ray emissions on and off the γ-ray cocoon of hard cosmic rays revealed by the…
Chromospheric Rapid Blueshifted Excursions Observed with IBIS and their Association with Photospheric Magnetic Field Evolution
Liu, Chang; Jing, Ju; Denker, Carsten +9 more
Chromospheric rapid blueshifted excursions (RBEs) are suggested to be the disk counterparts of type II spicules at the limb and believed to contribute to the coronal heating process. Previous identification of RBEs was mainly based on feature detection using Dopplergrams. In this paper, we study RBEs on 2011 October 21 in a very quiet region at th…