Search Publications
VLBA Trigonometric Parallax Measurement of the Semi-regular Variable RT Vir
Menten, Karl M.; Honma, Mareki; Reid, Mark J. +4 more
We report a trigonometric parallax measurement of 22 GHz H2O masers toward the semi-regular variable RT Vir from multi-epoch Very Long Baseline Array observations. The parallax of 4.417 ± 0.134 mas, corresponding to a distance of 226 ± 7 pc, is significantly different from the Hipparcos parallax, but is consistent with a distance derive…
Discovery of an H I-rich Gas Reservoir in the Outskirts of SZ-effect-selected Clusters
Nagai, Daisuke; Schaye, Joop; Muzahid, Sowgat +2 more
We report on the detection of three strong H I absorbers originating in the outskirts (I.e., impact parameter, {ρ }{cl} ≈ (1.6-4.7)r 500) of three massive ({M}500∼ 3× {10}14 M ⊙) clusters of galaxies at redshift {z}{cl}≈ 0.46, in the Hubble Space Telescope Cosmic Origins Spectrograp…
Observations of Lyα and O VI: Signatures of Cooling and Star Formation in a Massive Central Cluster Galaxy
Donahue, Megan; Voit, G. Mark; Connor, Thomas +1 more
We report new Hubble Space Telescope COS and Space Telescope Imaging Spectrograph spectroscopy of a star-forming region (∼ 100 {M}⊙ yr-1) in the center of the X-ray cluster RX J1532.9+3021 (z = 0.362), to follow-up the CLASH team discovery of luminous UV filaments and knots in the central massive galaxy. We detect broad (∼50…
Interchange Reconnection Associated with a Confined Filament Eruption: Implications for the Source of Transient Cold-dense Plasma in Solar Winds
Li, Gang; Chen, Yao; Zheng, Ruisheng +2 more
The cold-dense plasma is occasionally detected in the solar wind with in situ data, but the source of the cold-dense plasma remains illusive. Interchange reconnections (IRs) between closed fields and nearby open fields are known to contribute to the formation of solar winds. We present a confined filament eruption associated with a puff-like coron…
ALMA Discovery of Solar Umbral Brightness Enhancement at λ = 3 mm
Solanki, Sami K.; Shimojo, Masumi; White, Stephen M. +2 more
We report the discovery of a brightness enhancement in the center of a large sunspot umbra at a wavelength of 3 mm using the Atacama Large Millimeter/sub-millimeter Array (ALMA). Sunspots are among the most prominent features on the solar surface, but many of their aspects are surprisingly poorly understood. We analyzed a λ = 3 mm (100 GHz) mosaic…
Expanding and Contracting Coronal Loops as Evidence of Vortex Flows Induced by Solar Eruptions
Aulanier, G.; Schmieder, B.; Démoulin, P. +2 more
Eruptive solar flares were predicted to generate large-scale vortex flows at both sides of the erupting magnetic flux rope. This process is analogous to a well-known hydrodynamic process creating vortex rings. The vortices lead to advection of closed coronal loops located at the peripheries of the flaring active region. Outward flows are expected …
AGN Activity in Nucleated Galaxies as Measured by Chandra
Baldassare, Vivienne F.; Gültekin, Kayhan; Gnedin, Oleg Y. +4 more
Motivated by theoretical expectations that nuclear star clusters (NSCs) in galactic centers may provide a favorable environment for supermassive black holes to form and/or efficiently grow, we set out to measure the fraction of nearby nucleated galaxies that also host an active galactic nucleus. We targeted a distance-limited sample of 98 objects …
Dust in Clusters: Separating the Contribution of Galaxies and Intracluster Media
López-Corredoira, M.; Gutiérrez, C. M.
We have analyzed a sample of 327 clusters of galaxies, spanning the range of 0.06-0.70 in redshift. Strong constraints on their mean intracluster emission of dust have been obtained using maps and catalogs from the Herschel MerMES project; within a radius of 5 arcmin centered in each cluster, the 95% C.L. limits obtained are 86.6, 48.2, and 30.9 m…
A Heuristic Approach to Remove the Background Intensity on White-light Solar Images. I. STEREO/HI-1 Heliospheric Images
Stenborg, Guillermo; Howard, Russell A.
White-light coronal and heliospheric imagers observe scattering of photospheric light from both dust particles (the F-Corona) and free electrons in the corona (the K-corona). The separation of the two coronae is thus vitally important to reveal the faint K-coronal structures (e.g., streamers, co-rotating interaction regions, coronal mass ejections…
Constraining C III] Emission in a Sample of Five Luminous z = 5.7 Galaxies
Siana, Brian; Fan, Xiaohui; Jiang, Linhua +6 more
Recent observations have suggested that the C III]λ 1907/1909 emission lines could be alternative diagnostic lines for galaxies in the reionization epoch. We use the F128N narrowband filter on the Hubble Space Telescope’s (HST) Wide Field Camera 3 (WFC3) to search for C III] emission in a sample of five galaxies at z = 5.7 in the Subaru Deep Field…