Search Publications
Missions
Journals
Publication Years
Processing of Polycyclic Aromatic Hydrocarbons in Molecular-Loop Regions near the Galactic Center Revealed by AKARI
Oyabu, Shinki; Onaka, Takashi; Yamagishi, Mitsuyoshi +7 more
We present an AKARI mid-infrared diffuse map of an area of about 4° × 3° near the Galactic center in the 9 µm band. The band intensity is mostly attributed to aromatic hydrocarbon infrared emissions of carbonaceous grains at wavelengths of 6.2, 7,7, 8.6, and 11.3 µm. We detected 9 µm emission structures extending from the Galacti…
Flux transfer events: Motion and signatures
Omidi, N.; Sibeck, D. G.
We present results from a 2.5 dimensional hybrid code simulation for the evolution of flux transfer events (FTEs) during intervals of due southward interplanetary magnetic field (IMF) orientation. The structures invariably form between pairs of reconnection lines, often remaining nearly stationary on the subsolar magnetopause before their motion b…
Axial symmetry breaking of Saturn's thermosphere
Achilleos, N.; Smith, C. G. A.
The source of the various planetary-period signals in Saturn's magnetosphere is at present unknown. We investigate the possibility that the source of these signals is an axially asymmetric wind system in the thermosphere. We describe a feedback mechanism that has the potential to drive such axially asymmetric wind systems. The proposed mechanism r…
Hunting for Young Dispersing Star Clusters in IC 2574
Pellerin, Anne; Harris, Jason; Meyer, Martin M. +1 more
Dissolving stellar groups are very difficult to detect using traditional surface photometry techniques. We have developed a method to find and characterize non-compact stellar systems in galaxies where the young stellar population can be spatially resolved. By carrying out photometry on individual stars, we are able to separate the luminous blue s…
Velocity Characteristics of Rotating Sunspots
Alexander, D.; Zhu, C.; Tian, L.
A statistical study is carried out to investigate the detailed relationship between rotating sunspots and the emergence of magnetic flux tubes. This paper presents the velocity characteristics of 132 sunspots in 95 solar active regions. The rotational characteristics of the sunspots are calculated from successive SOHO/MDI magnetograms by applying …
Cassini VIMS Observations Show Ethane is Present in Titan's Rainfall
Nicholson, Philip D.; Sotin, Christophe; Barnes, Jason W. +6 more
Observations obtained over two years by the Cassini Imaging Science Subsystem suggest that rain showers fall on the surface. Using measurements obtained by the Visual Infrared Mapping Spectrometer, we identify the main component of the rain to be ethane, with methane as an additional component. We observe five or six probable rainfall events, at l…
The high-field polar RX J1007.5-2017
Burwitz, V.; Beuermann, K.; Schwope, A. D. +2 more
We report optical and X-ray observations of the high-field polar RX J1007.5-2017 performed between 1990 and 2012. It has an orbital period of 208.60 min determined from the ellipsoidal modulation of the secondary star in an extended low state. The spectral flux of the dM3 - secondary star yields a distance of 790 ± 105 pc. At low accretion levels,…
Ongoing Massive Star Formation in NGC 604
Groves, B.; Brandl, B.; Hunter, D. +1 more
NGC 604 is the second most massive H II region in the Local Group, thus an important laboratory for massive star formation. Using a combination of observational and analytical tools that include Spitzer spectroscopy, Herschel photometry, Chandra imaging, and Bayesian spectral energy distribution fitting, we investigate the physical conditions in N…
A Demonstration of Accurate Wide-field V-band Photometry Using a Consumer-grade DSLR Camera
Maravelias, G.; Eggenstein, H. -B.; Kloppenborg, B. K. +2 more
The authors examined the suitability of using a Digital Single Lens Reflex (DSLR) camera for stellar photometry and, in particular, investigated wide field exposures made with minimal equipment for analysis of bright variable stars. A magnitude-limited sample of stars was evaluated exhibiting a wide range of (B-V) colors taken from four fields bet…
Light echo of V838 Monocerotis: properties of the echoing medium
Tylenda, R.; Kamiński, T.
Context. The light echo phenomenon that accompanied the 2002 eruption of V838 Mon allows one to study the properties of the diffuse dusty matter in the vicinity of the object.
Aims: We are aiming at obtaining estimates of the optical thickness of the circumstellar matter in front of V838 Mon, as well as optical properties of dust grains in th…