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Giant Chromospheric Anemone Jet Observed with Hinode and Comparison with Magnetohydrodynamic Simulations: Evidence of Propagating Alfvén Waves and Magnetic Reconnection
DOI: 10.1086/591445 Bibcode: 2008ApJ...683L..83N

Shibata, K.; Katsukawa, Y.; Okamoto, T. J. +4 more

Hinode discovered a beautiful giant jet with both cool and hot components at the solar limb on 2007 February 9. Simultaneous observations by the Hinode SOT, XRT, and TRACE 195 Å satellites revealed that hot (~5 × 106 K) and cool (~104 K) jets were located side by side and that the hot jet preceded the associated cool jet (~1-…

2008 The Astrophysical Journal
Hinode 174
The Sloan Lens ACS Survey. VI. Discovery and Analysis of a Double Einstein Ring
DOI: 10.1086/529541 Bibcode: 2008ApJ...677.1046G

Treu, Tommaso; Gavazzi, Raphaël; Marshall, Philip J. +4 more

We report the discovery of two concentric Einstein rings around the gravitational lens SDSS J0946+1006. The main lens is at redshift zl = 0.222, while the inner ring (1) is at redshift zs1 = 0.609 (REin 1 = 1.43'' +/- 0.01''). The wider image separation (REin 2 = 2.07''+/- 0.02'') of the outer ring (2) i…

2008 The Astrophysical Journal
eHST 174
Solar Surface Emerging Flux Regions: A Comparative Study of Radiative MHD Modeling and Hinode SOT Observations
DOI: 10.1086/591245 Bibcode: 2008ApJ...687.1373C

Cheung, M. C. M.; Tarbell, T. D.; Title, A. M. +1 more

We present results from numerical modeling of emerging flux regions on the solar surface. The modeling was carried out by means of three-dimensional (3D) radiative MHD simulations of the rise of buoyant magnetic flux tubes through the convection zone and into the photosphere. Due to the strong stratification of the convection zone, the rise result…

2008 The Astrophysical Journal
Hinode 172
Multiple Stellar Populations in Three Rich Large Magellanic Cloud Star Clusters
DOI: 10.1086/590343 Bibcode: 2008ApJ...681L..17M

Mackey, A. D.; Ferguson, A. M. N.; Broby Nielsen, P. +1 more

We present deep color-magnitude diagrams for three rich intermediate-age star clusters in the LMC, constructed from archival ACS F435W and F814W imaging. All three clusters exhibit clear evidence for peculiar main-sequence turnoffs. NGC 1846 and 1806 each possess two distinct turnoff branches, while the turnoff for NGC 1783 shows a much larger spr…

2008 The Astrophysical Journal
eHST 171
The Current Sheet Associated with the 2003 November 4 Coronal Mass Ejection: Density, Temperature, Thickness, and Line Width
DOI: 10.1086/590655 Bibcode: 2008ApJ...686.1372C

Raymond, J. C.; Ciaravella, A.

In the wake of the 2003 November 4 coronal mass ejection associated with the largest solar flare of the last sunspot cycle, a current sheet (CS) was observed by the Ultraviolet Coronagraph Spectrometer (UVCS) as a narrow bright feature in the [Fe XVIII] (106.8 K) line. This is the first UV observation in which the CS evolution is follow…

2008 The Astrophysical Journal
SOHO 167
An Explanation for the Observed Weak Size Evolution of Disk Galaxies
DOI: 10.1086/523661 Bibcode: 2008ApJ...672..776S

Bell, Eric F.; Somerville, Rachel S.; Wisotzki, Lutz +14 more

Surveys of distant galaxies with the Hubble Space Telescope and from the ground have shown that there is only mild evolution in the relationship between radial size and stellar mass for galactic disks from z ~ 1 to the present day. Using a sample of nearby disk-dominated galaxies from the Sloan Digital Sky Survey (SDSS) and high-redshift data from…

2008 The Astrophysical Journal
eHST 164
Coronal Plasma Motions near Footpoints of Active Region Loops Revealed from Spectroscopic Observations with Hinode EIS
DOI: 10.1086/588252 Bibcode: 2008ApJ...678L..67H

Harra, Louise K.; Doschek, George A.; Hara, Hirohisa +4 more

The solar active region 10938 has been observed from the disk center to the west limb with the Hinode EUV Imaging Spectrometer. In the disk-center observation, subsonic upflow motions of tens of km s-1 and enhanced nonthermal velocities have been found near the footpoints of the active region loops assuming a single Gaussian approximati…

2008 The Astrophysical Journal
Hinode 161
Emergence of a Helical Flux Rope under an Active Region Prominence
DOI: 10.1086/528792 Bibcode: 2008ApJ...673L.215O

Shibata, Kazunari; Tsuneta, Saku; Shimizu, Toshifumi +12 more

Continuous observations were obtained of NOAA AR 10953 with the Solar Optical Telescope (SOT) on board the Hinode satellite from 2007 April 28 to May 9. A prominence was located over the polarity inversion line (PIL) to the southeast of the main sunspot. These observations provided us with a time series of vector magnetic fields on the photosphere…

2008 The Astrophysical Journal
Hinode 160
Cosmic Evolution of Black Holes and Spheroids. III. The MBH* Relation in the Last Six Billion Years
DOI: 10.1086/588804 Bibcode: 2008ApJ...681..925W

Treu, Tommaso; Malkan, Matthew A.; Blandford, Roger D. +1 more

We measure the evolution of the correlation between black hole mass and host spheroid velocity dispersion (MBH*) over the last 6 billion years, by studying three carefully selected samples of active galaxies at z = 0.57, z = 0.36 and z < 0.1. For all three samples, virial black hole masses are consistently estimated usin…

2008 The Astrophysical Journal
eHST 159
The Evolution of AGN Host Galaxies: From Blue to Red and the Influence of Large-Scale Structures
DOI: 10.1086/527283 Bibcode: 2008ApJ...675.1025S

Popesso, P.; Lehmer, B. D.; Alexander, D. M. +14 more

We present an analysis of 109 moderate-luminosity (41.9 <= log L0.5-8.0 keV <= 43.7) AGNs in the Extended Chandra Deep Field-South survey, which is drawn from 5549 galaxies from the COMBO-17 and GEMS surveys having 0.4 <= z<= 1.1. These obscured or optically weak AGNs facilitate the study of their host galaxies since the AGN…

2008 The Astrophysical Journal
eHST 159