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Mid-IR FORCAST/SOFIA Observations of M82
Gull, G. E.; Schoenwald, J.; Morris, M. R. +9 more
We present 75'' × 75'' size maps of M82 at 6.4 µm, 6.6 µm, 7.7 µm, 31.5 µm, and 37.1 µm with a resolution of ~4'' that we have obtained with the mid-IR camera FORCAST on SOFIA. We find strong emission from the inner 60'' (~1 kpc) along the major axis, with the main peak 5'' west-southwest of the nucleus and a secondar…
Four Decades of IRC +10216: Evolution of a Carbon-rich Dust Shell Resolved at 10 µm with MMT Adaptive Optics and MIRAC4
Marengo, Massimo; Hoffmann, William F.; Close, Laird M. +3 more
The evolved carbon-rich asymptotic giant branch star IRC +10216 (CW Leo) is the brightest mid-infrared source outside the solar system, as well as one of the closest examples of an evolved star losing mass. It has a complex and variable circumstellar structure on small scales in the near-infrared, and mid-infrared interferometry has revealed a dyn…
Hubble Space Telescope Pixel Analysis of the Interacting S0 Galaxy NGC 5195 (M51B)
Lee, Jong Chul; Kim, Minjin; Lee, Joon Hyeop +4 more
We report the properties of the interacting S0 galaxy NGC 5195 (M51B), revealed in a pixel analysis using the Hubble Space Telescope/Advanced Camera for Surveys images in the F435W, F555W, and F814W (BVI) bands. We analyze the pixel color-magnitude diagram (pCMD) of NGC 5195, focusing on the properties of its red and blue pixel sequences and the d…
Detection of X-Ray Periodicity from a New Eclipsing Polar Candidate XGPS-I J183251-100106
Hui, C. Y.; Lin, L. C. C.; Seo, K. A. +2 more
We report the results from a detailed analysis of an archival XMM-Newton observation of the X-ray source XGPS-I J183251-100106, which has been suggested as a promising magnetic cataclysmic variable (CV) candidate based on its optical properties. A single periodic signal of ~1.5 hr is detected from all EPIC instruments on board XMM-Newton. The phas…
Cloud and Haze in the Winter Polar Region of Titan Observed with Visual and Infrared Mapping Spectrometer on Board Cassini
Le Mouélic, S.; Sotin, C.; Brown, R. H. +1 more
A large cloud in the north polar region of Titan was first observed by the Visual and Infrared Mapping Spectrometer (VIMS) in 2005 and then in 2006. This cloud, confined beyond the latitude 62°N, is surrounded by a mixture of aerosol and mist probably lying in the low stratosphere and troposphere. Subsequent images of this region of Titan show a g…
Constraining the Optical Emission from the Double Pulsar System J0737-3039
Dalessandro, E.; Camilo, F.; Pellizzoni, A. +10 more
We present the first optical observations of the unique system J0737-3039 (composed of two pulsars, hereafter PSR-A and PSR-B). Ultra-deep optical observations, performed with the High Resolution Camera of the Advanced Camera for Surveys on board the Hubble Space Telescope, could not detect any optical emission from the system down to m F435W…
Frequency of Maunder Minimum Events in Solar-type Stars Inferred from Activity and Metallicity Observations
Tytler, David; Lubin, Dan; Kirkman, David
We consider the common proposition that the fraction of chromospherically very inactive stars in a solar-type sample is analogous to the fraction of the Sun's main-sequence lifetime spent in a grand minimum state. In a new approach to this proposition, we examine chromospheric activity log R'HK in a stellar sample having Hipparcos paral…
Solar Cycle Variation of Sound Speed inside the Sun
Mullan, D. J.; Rabello-Soares, M. C.; MacDonald, J.
Empirical radial profiles of the changes in sound speed inside the Sun between solar minimum and solar maximum have been extracted from Michelson Doppler Imager data by Baldner & Basu and Rabello-Soares. Here, we compare these results with the theoretical radial profiles predicted by a model of magnetic inhibition of convective onset: In the m…
Cosmic Origins Spectrograph Observations of NGC 2024: An Indirect View into the Heart of the Flame
France, Kevin; Snow, Theodore P.; Burgh, Eric B.
As part of a program to study translucent interstellar clouds, NGC 2024 IRS 1 was observed by the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope. IRS 1 is a heavily reddened B0.5 V star (E(B - V) = 1.69, RV = 4.5, and AV = 7.61) lying outside the core of the NGC 2024 cluster and not considered to be the…
Probable Identification of the On-disk Counterpart of Spicules in Hinode Ca II H Observations
de Wijn, A. G.
I present a study of high-resolution time series of Ca II H images and Fe I 630.15 nm spectra taken with the Solar Optical Telescope on the Hinode spacecraft. There is excellent correspondence between the Ca II H and the Fe I line core intensity, except tenuous emission around the network field concentrations in the former that is absent in the la…