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Waves as the Source of Apparent Twisting Motions in Sunspot Penumbrae
Solanki, S. K.; Bharti, L.; Hirzberger, J. +2 more
The motion of dark striations across bright filaments in a sunspot penumbra has become an important new diagnostic of convective gas flows in penumbral filaments. The nature of these striations has, however, remained unclear. Here, we present an analysis of small-scale motions in penumbral filaments in both simulations and observations. The simula…
Observations of Outflowing Ultraviolet Absorbers in NGC 4051 with the Cosmic Origins Spectrograph
Turner, T. J.; Kraemer, S. B.; Crenshaw, D. M. +6 more
We present new Hubble Space Telescope (HST)/Cosmic Origins Spectrograph (COS) observations of the narrow-line Seyfert 1 galaxy NGC 4051. These data were obtained as part of a coordinated observing program including X-ray observations with the Chandra/High Energy Transmission Grating (HETG) spectrometer and Suzaku. We detected nine kinematic compon…
Magnetic Topology of a Naked Sunspot: Is It Really Naked?
Sainz Dalda, A.; Tarbell, T. D.; Vargas Domínguez, S.
The high spatial, temporal, and spectral resolution achieved by Hinode instruments gives much better understanding of the behavior of some elusive solar features, such as pores and naked sunspots. Their fast evolution and, in some cases, their small sizes have made their study difficult. The moving magnetic features (MMFs) have been studied during…
A Multi-wavelength Study of the Jet, Lobes, and Core of the Quasar PKS 2101-490
Birkinshaw, M.; Worrall, D. M.; Schwartz, D. A. +9 more
We present a detailed study of the x-ray, optical, and radio emission from the jet, lobes, and core of the quasar PKS 2101-490 as revealed by new Chandra, Hubble Space Telescope (HST), and ATCA images. We extract the radio to x-ray spectral energy distributions from seven regions of the 13'' jet, and model the jet x-ray emission in terms of Dopple…
Spitzer Observations of Shock-excited Hydrogen Deuteride in IC 443C, HH 7, and HH 54: Probing the Gas-phase Deuterium Abundance in the Dense Interstellar Medium
Watson, Dan M.; Yuan, Yuan; Neufeld, David A. +2 more
We present and analyze observations—carried out using the Infrared Spectrograph (IRS) on the Spitzer Space Telescope—of the R(3) and R(4) pure rotational lines of hydrogen deuteride (HD) detected from shock-heated material associated with the supernova remnant IC 443C and with the Herbig-Haro objects HH 7 and HH 54. Assuming a continuous temperatu…
Spectroscopic Follow-up of X-Ray Sources in the ChaMPlane Survey: Identification of a New Cataclysmic Variable
van den Berg, M.; Allen, B.; Servillat, M. +3 more
We present a multi-object optical spectroscopy follow-up study of X-ray sources in a field along the Galactic plane (l = 327fdg42, b = 2fdg26) which is part of the Chandra Multi-wavelength Plane survey (ChaMPlane). We obtained spectra for 46 stars, including 15 likely counterparts to X-ray sources, and sources showing an Hα color excess. This has …
The Properties of Two Low-redshift O VI Absorbers and Their Associated Galaxies toward 3c 263
Savage, B. D.; Narayanan, A.; Wakker, B. P. +4 more
Ultraviolet observations of the QSO 3C 263 (z em = 0.652) with Cosmic Origins Spectrograph and FUSE reveal O VI absorption systems at z = 0.06342 and 0.14072. WIYN multi-object spectrograph observations provide information about the galaxies associated with the absorbers. The multi-phase system at z = 0.06342 traces cool photoionized ga…
Systematic Motion of Fine-scale Jets and Successive Reconnection in Solar Chromospheric Anemone Jet Observed with the Solar Optical Telescope/Hinode
Shibata, K.; Isobe, H.; Singh, K. A. P. +1 more
The Solar Optical Telescope (SOT) on board Hinode allows observations with high spatiotemporal resolution and stable image quality. A λ-shaped chromospheric anemone jet was observed in high resolution with SOT/Hinode. We found that several fine-scale jets were launched from one end of the footpoint to the other. These fine-scale jets (~1.5-2.5 Mm)…
Observations from SDO, Hinode, and STEREO of a Twisting and Writhing Start to a Solar-filament-eruption Cascade
Hara, Hirohisa; Moore, Ronald L.; Sterling, Alphonse C.
We analyze data from SDO (AIA, HMI), Hinode (SOT, XRT, EIS), and STEREO (EUVI) of a solar eruption sequence of 2011 June 1 near 16:00 UT, with an emphasis on the early evolution toward eruption. Ultimately, the sequence consisted of three emission bursts and two filament ejections. SDO/AIA 304 Å images show absorbing-material strands initially in …
Hot Diffuse Emission in the Nuclear Starburst Region of NGC 2903
Soria, Roberto; Tennant, Allyn F.; Swartz, Douglas A. +2 more
We present a deep Chandra observation of the central regions of the late-type barred spiral galaxy NGC 2903. The Chandra data reveal soft (kTe ~ 0.2-0.5 keV) diffuse emission in the nuclear starburst region and extending ~2' (~5 kpc) to the north and west of the nucleus. Much of this soft hot gas is likely to be from local active star-f…