Search Publications

Detection of Supergranulation Alignment in Polar Regions of the Sun by Helioseismology
DOI: 10.1088/2041-8205/726/2/L17 Bibcode: 2011ApJ...726L..17N

Zhao, Junwei; Kosovichev, Alexander G.; Sekii, Takashi +1 more

We report on a new phenomenon of "alignment" of supergranulation cells in the polar regions of the Sun. Recent high-resolution data sets obtained by the Solar Optical Telescope on board the Hinode satellite enabled us to investigate supergranular structures in high-latitude regions of the Sun. We have carried out a local helioseismology time-dista…

2011 The Astrophysical Journal
Hinode 43
Water Production by Comet 103P/Hartley 2 Observed with the SWAN Instrument on the SOHO Spacecraft
DOI: 10.1088/2041-8205/734/1/L6 Bibcode: 2011ApJ...734L...6C

Bertaux, J. -L.; Combi, M. R.; Quémerais, E. +2 more

Global water production rates were determined from the Lyα emission of hydrogen around comet 103P/Hartley 2, observed with the SWAN (Solar Wind Anisotropies) all-sky camera on the SOHO spacecraft from 2010 September 14 through December 12. This time period included the November 4 flyby by the EPOXI spacecraft. Water production was three times lowe…

2011 The Astrophysical Journal
SOHO 43
HST/COS Observations of Galactic High-velocity Clouds: Four Active Galactic Nucleus Sight Lines through Complex C
DOI: 10.1088/0004-637X/739/2/105 Bibcode: 2011ApJ...739..105S

Shull, J. Michael; Lockman, Felix J.; Penton, Steven V. +3 more

We report ultraviolet spectra of Galactic high-velocity clouds (HVCs) in Complex C, taken by the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST), together with new 21 cm spectra from the Green Bank Telescope. The wide spectral coverage and higher signal-to-noise ratio, compared to previous HST spectra, provide better velocity…

2011 The Astrophysical Journal
eHST 43
Spectroscopic Observations of Continuous Outflows and Propagating Waves from NOAA 10942 with Extreme Ultraviolet Imaging Spectrometer/Hinode
DOI: 10.1088/2041-8205/737/2/L43 Bibcode: 2011ApJ...737L..43N

Hara, H.; Nishizuka, N.

We focused on "sit-and-stare" observations of an outflow region at the edge of active region NOAA 10942 on 2007 February 20 obtained by the Extreme ultraviolet Imaging Spectrometer on board Hinode. We analyzed the data above the base of the outflow and found both continuous outflows and waves, which propagate from the base of the outflow. The spec…

2011 The Astrophysical Journal
Hinode 43
Infrared Spectra and Spectral Energy Distributions for Dusty Starbursts and Active Galactic Nuclei
DOI: 10.1088/0004-637X/730/1/19 Bibcode: 2011ApJ...730...19S

Lebouteiller, Vianney; Weedman, Daniel; Sargsyan, Lusine +4 more

We present spectroscopic results for all galaxies observed with the Spitzer Infrared Spectrograph (IRS) that also have total infrared fluxes f IR measured with the Infrared Astronomical Satellite (IRAS), also using AKARI photometry when available. Infrared luminosities and spectral energy distributions (SEDs) from 8 µm to 160 &mic…

2011 The Astrophysical Journal
AKARI 43
Spectroscopic Observations of a Coronal Moreton Wave
DOI: 10.1088/2041-8205/737/1/L4 Bibcode: 2011ApJ...737L...4H

Veronig, Astrid; Harra, Louise K.; Sterling, Alphonse C. +1 more

We observed a coronal wave (EIT wave) on 2011 February 16, using EUV imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and EUV spectral data from the Hinode/EUV Imaging Spectrometer (EIS). The wave accompanied an M1.6 flare that produced a surge and a coronal mass ejection (CME). EIS data of the wave show a promin…

2011 The Astrophysical Journal
Hinode 42
Hubble Space Telescope Imaging of Post-starburst Quasars
DOI: 10.1088/0004-637X/741/2/106 Bibcode: 2011ApJ...741..106C

Canalizo, G.; Shang, Zhaohui; Brotherton, M. S. +7 more

We present images of 29 post-starburst quasars (PSQs) from a Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Wide Field Channel Snapshot program. These broadlined active galactic nuclei (AGNs) possess the spectral signatures of massive (M burst ~ 1010 M sun), moderate-aged stellar populations (hundre…

2011 The Astrophysical Journal
eHST 42
COS Observations of Metal Line and Broad Lyman-α Absorption in the Multi-phase O VI and Ne VIII System at z = 0.20701 toward HE 0226-4110
DOI: 10.1088/0004-637X/743/2/180 Bibcode: 2011ApJ...743..180S

Savage, B. D.; Narayanan, A.; Lehner, N.

Observations of the QSO HE 0226-4110 (z em = 0.495) with the Cosmic Origins Spectrograph (COS) from 1134 to 1796 Å with a resolution of ~17 km s-1 and signal-to-noise ratio (S/N) per resolution element of 20-40 are used to study the multi-phase absorption system at z = 0.20701 containing O VI and Ne VIII. The system was previ…

2011 The Astrophysical Journal
eHST 41
Early-type Galaxies at z ~ 1.3. III. On the Dependence of Formation Epochs and Star Formation Histories on Stellar Mass and Environment
DOI: 10.1088/0004-637X/732/2/94 Bibcode: 2011ApJ...732...94R

Ford, H. C.; Demarco, R.; Treu, T. +20 more

We study the environmental dependence of stellar population properties at z ~ 1.3. We derive galaxy properties (stellar masses, ages, and star formation histories) for samples of massive, red, passive early-type galaxies (ETGs) in two high-redshift clusters, RXJ0849+4452 and RXJ0848+4453 (with redshifts of z = 1.26 and 1.27, respectively), and com…

2011 The Astrophysical Journal
eHST 41
The Mass-Lx Relation for Moderate Luminosity X-ray Clusters
DOI: 10.1088/0004-637X/726/1/48 Bibcode: 2011ApJ...726...48H

McNamara, Brian R.; Donahue, Megan; Voit, G. Mark +2 more

We present measurements of the masses of a sample of 25 moderate X-ray luminosity clusters of galaxies from the 160 square degree ROSAT survey. The masses were obtained from a weak-lensing analysis of deep F814W images obtained using the Advanced Camera for Surveys. We present an accurate empirical correction for the effect of charge transfer (in)…

2011 The Astrophysical Journal
eHST 41