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Spectroscopic Analysis of an EIT Wave/dimming Observed by Hinode/EIS

Ding, M. D.; Chen, P. F.; Chen, F.

EUV Imaging Telescope (EIT) waves are a wavelike phenomenon propagating outward from the coronal mass ejection source region, with expanding dimmings following behind. We present a spectroscopic study of an EIT wave/dimming event observed by the Hinode/Extreme-ultraviolet Imaging Spectrometer. Although the identification of the wave front is somew…

TOPICAL REVIEW The solar UV-x-ray spectrum from 1.5 to 2000 Å

Doschek, G. A.; Feldman, U.

This review illustrates the potential of UV-x-ray spectroscopy for determining the physical conditions in the solar chromosphere, transition region and corona, and how spectroscopy can be used as a tool to understand the physical mechanisms governing the atmosphere. It also illustrates the potential for understanding transient events such as solar…

Spectrally distinct ejecta in Syrtis Major, Mars: Evidence for environmental change at the Hesperian-Amazonian boundary

Murchie, Scott L.; Ehlmann, Bethany L.; Mustard, John F. +2 more

Analysis of visible and near-infrared (VNIR) imaging spectrometer data of the Syrtis Major volcanic complex on Mars shows spectrally distinct ejecta (SDE) around a subset of the region's impact craters. We explore the nature of this spectral difference with the intention of constraining the physical cause of the distinction and the significance of…

Retreat of a giant cataract in a long-lived (3.7-2.6 Ga) martian outflow channel

Warner, N. H.; Gupta, S.; Muller, J. -P. +2 more

Fabry-Pérot Versus Slit Spectropolarimetry of Pores and Active Network: Analysis of IBIS and Hinode Data

Judge, Philip G.; Tritschler, Alexandra; Uitenbroek, Han +3 more

We discuss spectropolarimetric measurements of photospheric (Fe I 630.25 nm) and chromospheric (Ca II 854.21 nm) spectral lines in and around small magnetic flux concentrations, including a pore. Our long-term goal is to diagnose properties of the magnetic field near the base of the corona. We compare ground-based two-dimensional spectropolarimetr…

Confident thickness estimates for planetary surface deposits from concealed crater populations

Neukum, G.; Platz, T.; Michael, G. G.

An improved technique is presented to determine more accurately deposit thicknesses of any surface units using crater size-frequency distributions (CSFDs). This new approach enables thickness estimates of deposits that completely cover their underlying unit, i.e., where no flooded craters are observed. Here, the crater populations of the unit of i…

Tracing the Peculiar Dark Matter Structure in the Galaxy Cluster Cl 0024+17 with Intracluster Stars and Gas

Jee, M. J.

Intracluster light (ICL) is believed to originate from the stars stripped from cluster galaxies. They are no longer gravitationally bound to individual galaxies, but to the cluster, and their smooth distribution potentially makes them serve as much denser tracers of the cluster dark matter than the sparsely distributed cluster galaxies. We present…

Whistler Waves Driven by Anisotropic Strahl Velocity Distributions: Cluster Observations

Gurgiolo, C.; Goldstein, M. L.; Nieves-Chinchilla, T. +2 more

Observed properties of the strahl using high resolution 3D electron velocity distribution data obtained from the Cluster/PEACE experiment are used to investigate its linear stability. An automated method to isolate the strahl is used to allow its moments to be computed independent of the solar wind core+halo. Results show that the strahl can have …

Highly Ionized Plasma in the Halo of a Luminous Spiral Galaxy Near z = 0.225

Savage, Blair D.; Wakker, Bart P.; Narayanan, Anand

We present analyses of the physical conditions in the z(O VI) = 0.22496 and z(O VI) = 0.22638 multiphase absorption systems detected in the ultraviolet Hubble Space Telescope/STIS and FUSE spectra of the quasar H 1821+643 (m_V = 14.2, z_em = 0.297). Both absorbers are likely associated with the extended halo of a ~2L* _B

Hard X-ray identification of η Carinae and steadiness close to periastron

Walter, R.; Rauw, G.; Leyder, J. -C.

Context. The colliding-wind binary η Carinae exhibits soft X-ray thermal emission that varies strongly around the periastron passage. It has been found to have non-thermal emission, thanks to its detection in hard X-rays using INTEGRAL and Suzaku, and also in γ-rays with AGILE and Fermi.
Aims: This paper attempts to definitively identify η Ca…