Search Publications
Comparing the solar minima of cycles 22/23 and 23/24: The view from LASCO white light coronal images
Llebaria, A.; Lamy, P.; Floyd, O. +1 more
The Large Angle and Spectrometric Coronagraph LASCO-C2 aboard SOHO has now completed 17 years (1996-2012) of quasi-continuous white-light imaging of the corona from 2.2 to 6.5 solar radii, thus allowing an unprecedented view of its evolution over a solar cycle and a half including the minima of solar cycles 22/23 and 23/24. The corrected and calib…
The Properties of Lyα Nebulae: Gas Kinematics from Nonresonant Lines
Davé, Romeel; Yang, Yujin; Zabludoff, Ann +1 more
With the Very Large Telescope/X-shooter, we obtain optical and near-infrared spectra of six Lyα blobs at z ~ 2.3. For a total sample of eight Lyα blobs (including two that we have previously studied), the majority (6/8) have broadened Lyα profiles with shapes ranging from a single peak to symmetric or asymmetric double-peaked. The remaining two sy…
Conversion from mutual helicity to self-helicity observed with IRIS
Peter, H.; Zhang, J.; Li, L. P. +1 more
Context. In the upper atmosphere of the Sun observations show convincing evidence for crossing and twisted structures, which are interpreted as mutual helicity and self-helicity.
Aims: We use observations with the new Interface Region Imaging Spectrograph (IRIS) to show the conversion of mutual helicity into self-helicity in coronal structure…
Spectral and Timing Nature of the Symbiotic X-Ray Binary 4U 1954+319: The Slowest Rotating Neutron Star in an X-Ray Binary System
Enoto, Teruaki; Makishima, Kazuo; Pottschmidt, Katja +7 more
The symbiotic X-ray binary (SyXB) 4U 1954+319 is a rare system hosting a peculiar neutron star (NS) and an M-type optical companion. Its ~5.4 hr NS spin period is the longest among all known accretion-powered pulsars and exhibited large (~7%) fluctuations over 8 yr. A spin trend transition was detected with Swift/BAT around an X-ray brightening in…
Cusp observation at Saturn's high-latitude magnetosphere by the Cassini spacecraft
Coates, A. J.; Krupp, N.; Dougherty, M. K. +11 more
We report on the first analysis of magnetospheric cusp observations at Saturn by multiple in situ instruments onboard the Cassini spacecraft. Using this we infer the process of reconnection was occurring at Saturn's magnetopause. This agrees with remote observations that showed the associated auroral signatures of reconnection. Cassini crossed the…
Star Formation Quenching in High-redshift Large-scale Structure: Post-starburst Galaxies in the Cl 1604 Supercluster at z ~ 0.9
Kocevski, Dale D.; Wu, Po-Feng; Lubin, Lori M. +4 more
The Cl 1604 supercluster at z ~ 0.9 is one of the most extensively studied high-redshift large-scale structures, with more than 500 spectroscopically confirmed members. It consists of eight clusters and groups, with members numbering from a dozen to nearly a hundred, providing a broad range of environments for investigating the large-scale environ…
Synchrotron Self-inverse Compton Radiation from Reverse Shock on GRB 120326A
Yamaoka, Kazutaka; Urata, Yuji; Im, Myungshin +6 more
We present multi-wavelength observations of a typical long duration GRB 120326A at z = 1.798, including rapid observations using a Submillimeter Array (SMA) and a comprehensive monitoring in the X-ray and optical. The SMA observation provided the fastest detection to date among seven submillimeter afterglows at 230 GHz. The prompt spectral analysi…
A network of lava tubes as the origin of Labyrinthus Noctis and Valles Marineris on Mars
Leone, Giovanni
The role of lava tube networks and lava channels is reassessed as the primordial stage of the volcano-erosional processes that formed the Labyrinthus Noctis-Valles Marineris system instead of a tectonic origin. The combined use of CTX, CRISM, HiRISE imagery, and MOLA profiles has provided valuable insight in the evolution of pit chains into fossae…
Sérsic galaxy models in weak lensing shape measurement: model bias, noise bias and their interaction
Rowe, Barnaby; Kacprzak, Tomasz; Zuntz, Joe +4 more
Cosmic shear is a powerful probe of cosmological parameters, but its potential can be fully utilized only if galaxy shapes are measured with great accuracy. Two major effects have been identified which are likely to account for most of the bias seen for maximum likelihood methods in recent shear measurement challenges. Model bias occurs when the t…
A Prominence Eruption Driven by Flux Feeding from Chromospheric Fibrils
Wang, Yuming; Shen, Chenglong; Wang, S. +4 more
We present multi-wavelength observations of a prominence eruption originating from a quadrupolar field configuration, in which the prominence was embedded in a side arcade. Within the two-day period prior to its eruption on 2012 October 22, the prominence was perturbed three times by chromospheric fibrils underneath, which rose upward, became brig…