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Spectroscopic parameters for silacyclopropynylidene, SiC2, from extensive astronomical observations toward CW Leo (IRC +10216) with the Herschel satellite
Waters, L. B. F. M.; Cernicharo, José; Teyssier, D. +5 more
A molecular line survey has been carried out toward the carbon-rich asymptotic giant branch star CW Leo employing the HIFI instrument on board of the Herschel satellite. Numerous features from 480 GHz to beyond 1100 GHz could be assigned unambiguously to the fairly floppy SiC2 molecule. However, predictions from laboratory data exhibite…
Multipolar Planetary Nebulae: Not as Geometrically Diversified as Thought
Kwok, Sun; Tafoya, D.; Imai, H. +2 more
Planetary nebulae (PNe) have diverse morphological shapes, including point-symmetric and multipolar structures. Many PNe also have complicated internal structures such as tori, lobes, knots, and ansae. A complete accounting of all the morphological structures through physical models is difficult. A first step toward such an understanding is to der…
Swift/X-ray Telescope monitoring of the candidate supergiant fast X-ray transient IGR J16418-4532
Gehrels, N.; Esposito, P.; Ducci, L. +6 more
We report on the Swift monitoring of the candidate supergiant fast X-ray transient (SFXT) IGR J16418-4532, for which both orbital and spin periods are known (∼3.7 d and ∼1250 s, respectively). Our observations, for a total of ∼43 ks, span over three orbital periods and represent the most intense and complete sampling of the light curve of this sou…
Modeling the Accretion Structure of AU Mon
Peters, Geraldine J.; Miller, Brendan P.; Budaj, Ján +2 more
AU Mon is a long-period (11.113 days) Algol-type binary system with a persistent accretion disk that is apparent as double-peaked Hα emission. We present previously unpublished optical spectra of AU Mon which were obtained over 20 years from 1991-2011 with dense orbital phase coverage. We utilize these data, along with archival UV spectra, to mode…
Coronal Cells
Warren, H. P.; Sheeley, N. R., Jr.
We have recently noticed cellular features in Fe XII 193 Å images of the 1.2 MK corona. They occur in regions bounded by a coronal hole and a filament channel, and are centered on flux elements of the photospheric magnetic network. Like their neighboring coronal holes, these regions have minority-polarity flux that is ~0.1-0.3 times their flux of …
Predicting the number of giant arcs expected in the next-generation wide-field surveys from space
Meneghetti, Massimo; Giocoli, Carlo; Moscardini, Lauro +1 more
In this paper, we estimate the number of gravitational arcs detectable in a wide-field survey such as that which will be operated by the Euclid space mission, assuming a Λ cold dark matter cosmology. We use the publicly available code MOKA to obtain realistic deflection angle maps of mock gravitational lenses. The maps are processed by a ray-traci…
Hubble Space Telescope Observations of the Stellar Distribution near Sgr A*
Yusef-Zadeh, F.; Wardle, M.; Bushouse, H.
Sgr A* is embedded within the nuclear cluster, which consists of a mixture of evolved and young populations of stars dominating the light over a wide range of angular scales. Here we present Hubble Space Telescope/NICMOS data to study the surface brightness distribution of stellar light within the inner 10'' of Sgr A* at 1.45 µm, 1.7 µ…
The Resolved Stellar Population in 50 Regions of M83 from HST/WFC3 Early Release Science Observations
Mutchler, Max; McCarthy, Patrick J.; Calzetti, Daniela +22 more
We present a multi-wavelength photometric study of ~15,000 resolved stars in the nearby spiral galaxy M83 (NGC 5236, D = 4.61 Mpc) based on Hubble Space Telescope Wide Field Camera 3 observations using four filters: F336W, F438W, F555W, and F814W. We select 50 regions (an average size of 260 pc by 280 pc) in the spiral arm and inter-arm areas of M…
Power Spectra of Velocities and Magnetic Fields on the Solar Surface and their Dependence on the Unsigned Magnetic Flux Density
Katsukawa, Y.; Orozco Suárez, D.
We have performed power spectral analysis of surface temperatures, velocities, and magnetic fields, using spectropolarimetric data taken with the Hinode Solar Optical Telescope. When we make power spectra in a field of view covering the supergranular scale, kinetic and thermal power spectra have a prominent peak at the granular scale while the mag…
Small-scale variability in Saturn’s lower ionosphere
Matcheva, Katia I.; Barrow, Daniel J.
We perform and present a wavelet analysis on all 31 Cassini electron density profiles published to date (Nagy, A.F. et al. [2006]. J. Geophys. Res. 111 (A6), CiteID A06310; Kliore, A.J. et al. [2009]. J. Geophys. Res. 114 (A4), CiteID A04315). We detect several discrete scales of variability present in the observations. Small-scale variability (S …