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Anchoring the Distance Scale via X-Ray/Infrared Data for Cepheid Clusters: SU Cas
Bonatto, C.; Gallo, L.; Berdnikov, L. +5 more
New X-ray (XMM-Newton) and JHKs (Observatoire du Mont-Mégantic) observations for members of the star cluster Alessi 95, which Turner et al. discovered hosts the classical Cepheid SU Cas, were used in tandem with UCAC3 (proper motion) and Two Micron All Sky Survey observations to determine precise cluster parameters: E(J - H) = 0.08 ± 0.…
Newly identified star clusters in M33 - III. Structural parameters
Holtzman, J. A.; Sarajedini, A.; Garnett, D. R. +1 more
We present the morphological properties of 161 star clusters in M33 using the Advanced Camera for Surveys Wide Field Channel on-board the Hubble Space Telescope using observations with the F606W and F814W filters. We obtain, for the first time, ellipticities, position angles and surface brightness profiles for a significant number of clusters. On …
Lifetime test and heritage on orbit of coolers for space use
Nakagawa, Takao; Mitsuda, Kazuhisa; Murakami, Masahide +11 more
This report describes the results and operating status of ground lifetime testing and achievements on orbit of coolers for space use. Ground lifetime tests of coolers of three types were conducted to demonstrate their long life and reliability. Three single-stage Stirling coolers were tested for 89,016, 71,871 and 68,273 h from 1998, a two-stage S…
Ionized Reflection Spectra from Accretion Disks Illuminated by X-Ray Pulsars
Ballantyne, D. R.; Hickox, R. C.; Purvis, J. D. +1 more
X-ray reflection signatures are observed around multiple classes of accreting compact objects. Modeling these features yields important constraints on the physics of accretion disks, motivating the development of X-ray reflection models appropriate for a variety of systems and illumination conditions. Here, constant density ionized X-ray reflectio…
Cluster-cluster lensing and the case of Abell 383
Zitrin, Adi; Umetsu, Keiichi; Medezinski, Elinor +8 more
Extensive surveys of galaxy clusters motivate us to assess the likelihood of cluster-cluster lensing (CCL), namely, gravitational lensing of a background cluster by a foreground cluster. We briefly describe the characteristics of CCLs in optical, X-ray and Sunyaev-Zel'dovich effect measurements, and calculate their predicted numbers for Λ cold dar…
Investigating magnetospheric interaction effects on Titan's ionosphere with the Cassini orbiter Ion Neutral Mass Spectrometer, Langmuir Probe and magnetometer observations during targeted flybys
Luhmann, J. G.; Russell, C. T.; Dougherty, M. K. +13 more
In the ∼6 years since the Cassini spacecraft went into orbit around Saturn in 2004, roughly a dozen Titan flybys have occurred for which the Ion Neutral Mass Spectrometer (INMS) measured that moon's ionospheric density and composition. For these, and for the majority of the ∼60 close flybys probing to altitudes down to ∼950 km, Langmuir Probe elec…
Non-standard Energy Spectra of Shock-accelerated Solar Particles
Vainio, Rami; Valtonen, Eino; Kocharov, Leon +3 more
We consider a numerical model for the shock acceleration of energetic ions in the magnetic environment of the solar corona. The model is motivated by observations of the deka-to-hecto-MeV proton energy spectra, ion and electron timing, and abundances in the beginning of major solar energetic particle (SEP) events, prior to the event's main phase a…
Morphometry of Great Basin pluvial shore landforms: Implications for paleolake basins on Mars
Zimbelman, James R.; Irwin, Rossman P., III
Many basins with relict contributing valley networks and outlet valleys in the Martian highlands indicate past flowing and ponded water on the surface. These likely paleolakes motivate an investigation of pluvial shore landforms in the Great Basin region of the western United States, as confident identification of strandlines on Mars would facilit…
The Infrared Properties of Sources Matched in the WISE All-sky and Herschel ATLAS Surveys
Gardner, Jonathan P.; Tsai, Chao-Wei; Cava, Antonio +34 more
We describe the infrared properties of sources detected over ~36 deg2 of sky in the GAMA 15 hr equatorial field, using data from both the Herschel Astrophysical Terahertz Large-Area Survey (H-ATLAS) and Wide-field Infrared Survey (WISE). With 5σ point-source depths of 34 and 0.048 mJy at 250 µm and 3.4 µm, respectively, we a…
Charging of ice grains in Saturn's E ring: theory and observations
Misra, Shikha; Mishra, S. K.; Sodha, M. S.
We have developed a theoretical model for a physical understanding of the charging of ice grains in the plasma of Saturn's E ring. The evaluated results are compared with the available observations and measurements from the Cassini, Hubble Space Telescope, Voyager and Pioneer campaigns. In this formulation, we implement the uniform potential theor…