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Of "Cocktail Parties" and Exoplanets
DOI: 10.1088/0004-637X/747/1/12 Bibcode: 2012ApJ...747...12W

Waldmann, I. P.

The characterization of ever smaller and fainter extrasolar planets requires an intricate understanding of one's data and the analysis techniques used. Correcting the raw data at the 10-4 level of accuracy in flux is one of the central challenges. This can be difficult for instruments that do not feature a calibration plan for such high…

2012 The Astrophysical Journal
eHST 48
The Hubble Space Telescope Cluster Supernova Survey. III. Correlated Properties of Type Ia Supernovae and Their Hosts at 0.9 < Z < 1.46
DOI: 10.1088/0004-637X/750/1/1 Bibcode: 2012ApJ...750....1M

Gladders, M. D.; Lidman, C.; Rubin, D. +36 more

Using the sample of Type Ia supernovae (SNe Ia) discovered by the Hubble Space Telescope (HST) Cluster Supernova Survey and augmented with HST-observed SNe Ia in the Great Observatories Origins Deep Survey (GOODS) fields, we search for correlations between the properties of SNe and their host galaxies at high redshift. We use galaxy color and quan…

2012 The Astrophysical Journal
eHST 48
The Connection between Internetwork Magnetic Elements and Supergranular Flows
DOI: 10.1088/2041-8205/758/2/L38 Bibcode: 2012ApJ...758L..38O

Bellot Rubio, L. R.; Katsukawa, Y.; Orozco Suárez, D.

The advection of internetwork magnetic elements by supergranular convective flows is investigated using high spatial resolution, high cadence, and high signal-to-noise ratio Na I D1 magnetograms obtained with the Hinode satellite. The observations show that magnetic elements appear everywhere across the quiet Sun surface. We calculate the proper m…

2012 The Astrophysical Journal
Hinode 48
Narrow Dust Jets in a Diffuse Gas Coma: A Natural Product of Small Active Regions on Comets
DOI: 10.1088/0004-637X/749/1/29 Bibcode: 2012ApJ...749...29C

Combi, M. R.; Fougere, N.; Gombosi, T. I. +2 more

Comets often display narrow dust jets but more diffuse gas comae when their eccentric orbits bring them into the inner solar system and sunlight sublimates the ice on the nucleus. Comets are also understood to have one or more active areas covering only a fraction of the total surface active with sublimating volatile ices. Calculations of the gas …

2012 The Astrophysical Journal
Rosetta 48
X-Ray Observations of the New Unusual Magnetar Swift J1834.9-0846
DOI: 10.1088/0004-637X/748/1/26 Bibcode: 2012ApJ...748...26K

Pavlov, George G.; Kargaltsev, Oleg; Griffith, Roger L. +6 more

We present X-ray observations of the new transient magnetar Swift J1834.9-0846, discovered with the Swift Burst Alert Telescope on 2011 August 7. The data were obtained with Swift, Rossi X-ray Timing Explorer (RXTE), CXO, and XMM-Newton both before and after the outburst. Timing analysis reveals single peak pulsations with a period of 2.4823 s and…

2012 The Astrophysical Journal
XMM-Newton 48
Analysis of Quiet-Sun Internetwork Magnetic Fields Based on Linear Polarization Signals
DOI: 10.1088/0004-637X/751/1/2 Bibcode: 2012ApJ...751....2O

Bellot Rubio, L. R.; Orozco Suárez, D.

We present results from the analysis of Fe I 630 nm measurements of the quiet Sun taken with the spectropolarimeter of the Hinode satellite. Two data sets with noise levels of 1.2 × 10-3 and 3 × 10-4 are employed. We determine the distribution of field strengths and inclinations by inverting the two observations with a Milne-…

2012 The Astrophysical Journal
Hinode 47
Investigating the Reliability of Coronal Emission Measure Distribution Diagnostics using Three-dimensional Radiative Magnetohydrodynamic Simulations
DOI: 10.1088/0004-637X/758/1/54 Bibcode: 2012ApJ...758...54T

Testa, Paola; Martínez-Sykora, Juan; De Pontieu, Bart +2 more

Determining the temperature distribution of coronal plasmas can provide stringent constraints on coronal heating. Current observations with the Extreme ultraviolet Imaging Spectrograph (EIS) on board Hinode and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory provide diagnostics of the emission measure distribution (E…

2012 The Astrophysical Journal
Hinode 47
The First Maximum-light Ultraviolet through Near-infrared Spectrum of a Type Ia Supernova
DOI: 10.1088/2041-8205/753/1/L5 Bibcode: 2012ApJ...753L...5F

Filippenko, Alexei V.; Foley, Ryan J.; Kirshner, Robert P. +21 more

We present the first maximum-light ultraviolet (UV) through near-infrared (NIR) Type Ia supernova (SN Ia) spectrum. This spectrum of SN 2011iv was obtained nearly simultaneously by the Hubble Space Telescope at UV/optical wavelengths and the Magellan Baade telescope at NIR wavelengths. These data provide the opportunity to examine the entire maxim…

2012 The Astrophysical Journal
eHST 47
Precursor of Sunspot Penumbral Formation Discovered with Hinode Solar Optical Telescope Observations
DOI: 10.1088/2041-8205/747/2/L18 Bibcode: 2012ApJ...747L..18S

Shimizu, Toshifumi; Ichimoto, Kiyoshi; Suematsu, Yoshinori

We present observations of a precursory signature that would be helpful for understanding the formation process of sunspot penumbrae. The Hinode Solar Optical Telescope successfully captured the entire evolution of a sunspot from the pore to a large well-developed sunspot with penumbra in an emerging flux region appearing in NOAA Active Region 110…

2012 The Astrophysical Journal
Hinode 47
Measuring the Solar Radius from Space during the 2003 and 2006 Mercury Transits
DOI: 10.1088/0004-637X/750/2/135 Bibcode: 2012ApJ...750..135E

Kuhn, J. R.; Bush, R. I.; Emilio, M. +1 more

The Michelson Doppler Imager (MDI) aboard the Solar and Heliospheric Observatory observed the transits of Mercury on 2003 May 7 and 2006 November 8. Contact times between Mercury and the solar limb have been used since the seventeenth century to derive the Sun's size but this is the first time that high-quality imagery from space, above the Earth'…

2012 The Astrophysical Journal
SOHO 47