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Shaping the Glowing Eye Planetary Nebula, NGC 6751
López, J. A.; García-Díaz, Ma. T.; Richer, M. G. +2 more
NGC 6751 is a highly structured multiple-shell planetary nebula (PN) with a bipolar outflow. In this work, we present a comprehensive set of spatially resolved, high spectral resolution, long-slit spectra and deep imaging from San Pedro Mártir, Gemini, the Hα composite full sky survey and archive images from the Hubble Space Telescope and Spitzer.…
SMEI 3D Reconstruction of a Coronal Mass Ejection Interacting with a Corotating Solar Wind Density Enhancement: The 2008 April 26 CME
Webb, D. F.; Jackson, B. V.; Buffington, A. +3 more
The Solar Mass Ejection Imager (SMEI) has recorded the brightness responses of hundreds of interplanetary coronal mass ejections (CMEs) in the interplanetary medium. Using a three-dimensional (3D) reconstruction technique that derives its perspective views from outward-flowing solar wind, analysis of SMEI data has revealed the shapes, extents, and…
The Evolution of the Twist Shear and Dip Shear During X-class Flare of 2006 December 13: Hinode Observations
Gosain, Sanjay; Venkatakrishnan, P.
The non-potentiality of solar magnetic fields is traditionally measured in terms of a magnetic shear angle, i.e., the angle between the observed and potential field azimuths. Here, we introduce another measure of the shear that has not been previously studied in solar active regions, i.e., the one that is associated with the inclination angle of t…
Detection of Highly Ionized C IV Gas Within the Local Cavity
Welsh, Barry Y.; Lallement, Rosine; Wheatley, Jonathan +1 more
We present high resolution (R = 114,000) ultraviolet measurements of the interstellar absorption line profiles of the C IV (1550 Å) high ionization doublet recorded toward the nearby B2Ve star HD 158427 (d ~ 74 pc). These data, which were recorded with the recently re-furbished Space Telescope Imaging Spectrograph instrument on the Hubble Space Te…
Dust Obscuration in Lyman Break Galaxies at z ~ 4
Ho, I. -Ting; Wang, Wei-Hao; Morrison, Glenn E. +1 more
Measuring star formation rates (SFRs) in high-z galaxies with their rest-frame ultraviolet (UV) continuum can be uncertain because of dust obscuration. Prior studies had used the submillimeter emission at 850 µm to determine the intrinsic SFRs of rest-frame UV-selected galaxies, but the results suffered from the low sensitivity and poor reso…
Searching for Compact Objects in SNRs G27.8+0.6 and G28.8+1.5
Pavlov, George G.; Kargaltsev, Oleg; Misanovic, Zdenka
We analyzed XMM-Newton observations of two center-filled supernova remnants (SNRs), G27.8+0.6 and G28.8+1.5, to search for pulsars/pulsar wind nebulae (PWNe) and other types of neutron stars (NSs) associated with these remnants. We discovered a PWN candidate within the extent of the centrally peaked radio emission of G27.8+0.6. The X-ray morpholog…
Particle Acceleration in the Expanding Blast Wave of η Carina's Great Eruption of 1843
Hinton, J. A.; Domainko, W.; Ohm, S.
Non-thermal hard X-ray and high-energy (HE; 1 MeV <= E <= 100 GeV) γ-ray emission in the direction of η Carina has been recently detected using the INTEGRAL, AGILE, and Fermi satellites. So far this emission has been interpreted in the framework of particle acceleration in the colliding wind region between the two massive stars. However, the…
Magnetic Non-potentiality of Solar Active Regions and Peak X-ray Flux of the Associated Flares
Gosain, Sanjay; Tiwari, Sanjiv Kumar; Venkatakrishnan, P.
Predicting the severity of solar eruptive phenomena such as flares and coronal mass ejections remains a great challenge despite concerted efforts to do so over the past several decades. However, the advent of high-quality vector magnetograms obtained from Hinode (SOT/SP) has increased the possibility of meeting this challenge. In particular, the s…
Low-metallicity Star Formation in High-redshift Galaxies at z ~ 8
Taniguchi, Y.; Trump, J. R.; Shioya, Y.
Based on the recent very deep near-infrared imaging of the Hubble Ultra Deep Field with WFC3 on the Hubble Space Telescope, five groups published the most probable samples of galaxies at z ~ 8, selected by the so-called dropout method or photometric redshift; e.g., Y 105-dropouts (Y 105 - J 125 > 0.8). These stu…
A Search for Wide Companions to the Extrasolar Planetary System HR 8799
Close, Laird M.; Males, Jared R.
The extrasolar planetary system around HR 8799 is the first multiplanet system ever imaged. It is also, by a wide margin, the highest mass system with >27 Jupiters of planetary mass past 25 AU. This is a remarkable system with no analog in any other known planetary system. In the first part of this paper, we investigated the nature of two faint…