Search Publications
Comparison of the coronal mass ejection shock acceleration of three widespread SEP events during solar cycle 24
St. Cyr, O. C.; Gopalswamy, N.; Mäkelä, P. +1 more
We studied three solar energetic particle (SEP) events observed on 14 August 2010, 3 November 2011, and 5 March 2013 by Solar Terrestrial Relations Observatory (STEREO) A, B, and near-Earth (L1) spacecraft with a longitudinal distribution of particles >90°. Using a forward modeling method combined with extreme ultraviolet and white-light images…
Understanding the Links among the Magnetic Fields, Filament, Bipolar Bubble, and Star Formation in RCW 57A Using NIR Polarimetry
Tamura, M.; Nishiyama, S.; Wang, Jia-Wei +10 more
The influence of magnetic fields (B-fields) on the formation and evolution of bipolar bubbles, due to the expanding ionization fronts (I-fronts) driven by the H II regions that are formed and embedded in filamentary molecular clouds, has not been well-studied yet. In addition to the anisotropic expansion of I-fronts into a filament, B-fields are e…
The Solar Neighborhood. XLII. Parallax Results from the CTIOPI 0.9 m Program—Identifying New Nearby Subdwarfs Using Tangential Velocities and Locations on the H-R Diagram
Henry, Todd J.; Winters, Jennifer G.; Jao, Wei-Chun +4 more
Parallaxes, proper motions, and optical photometry are presented for 51 systems consisting of 37 cool subdwarf and 14 additional high proper motion systems. Thirty-seven systems have parallaxes reported for the first time, 15 of which have proper motions of at least 1″ yr-1. The sample includes 22 newly identified cool subdwarfs within …
Finite-frequency Sensitivity Kernels in Spherical Geometry for Time-Distance Helioseismology
Mandal, Krishnendu; Hanasoge, Shravan M.; Bhattacharya, Jishnu +1 more
The inference of internal properties of the Sun from surface measurements of wave travel times is the goal of time-distance helioseismology. A critical step toward the accurate interpretation of shifts in travel time is the computation of sensitivity functions linking seismic measurements to internal structure. Here we calculate finite-frequency s…
A deep search for the release of volcanic gases on Mars using ground-based high-resolution infrared and submillimeter spectroscopy: Sensitive upper limits for OCS and SO2
Villanueva, G. L.; Mumma, M. J.; Tokunaga, A. T. +1 more
Recent volcanic activity has long been considered a distinct possibility that would place major constraints on the evolution of Mars' interior. Volcanic activity would result in the outgassing of sulfur-bearing species. As part of our multi-band search for active release of volcanic gases on Mars, we looked for carbonyl sulfide (OCS) at its combin…
Recombining Plasma and Gamma-Ray Emission in the Mixed-morphology Supernova Remnant 3C 400.2
Fukui, Y.; Sano, H.; Sezer, A. +2 more
3C 400.2 belongs to the mixed-morphology supernova remnant class, showing center-filled X-ray and shell-like radio morphology. We present a study of 3C 400.2 with archival Suzaku and Fermi-LAT observations. We find recombining plasma (RP) in the Suzaku spectra of north-east and south-east regions. The spectra of these regions are well described by…
Spectral manifestations of extremely strong magnetic fields in the sunspot umbra
Lozitsky, V. G.
Fine peculiarities of the Zeeman effect in two big sunspots of October 29, 2003, and October 25, 2014, are analyzed. In order to search spectral evidences of very strong spatially unresolved magnetic fields, the Stokes I ± V and V profiles of the Fe I 6301.5 and 6302.5 Å lines are studied in detail. Confirmed are two effects discovered earlier by …
Sunward-propagating Solar Energetic Electrons inside Multiple Interplanetary Flux Ropes
Temmer, Manuela; Veronig, Astrid; Dresing, Nina +8 more
On 2013 December 2 and 3, the SEPT and STE instruments on board STEREO-A observed two solar energetic electron events with unusual sunward-directed fluxes. Both events occurred during a time interval showing typical signatures of interplanetary coronal mass ejections (ICMEs). The electron timing and anisotropies, combined with extreme-ultraviolet …
Night side distribution of SO2 content in Venus' upper mesosphere
Montmessin, F.; Bertaux, J. -L.; Fedorova, A. A. +6 more
In this paper we present the first night side distribution of SO2 content in Venus' upper mesosphere (altitudes from 85 to 105 km). The dataset is based on the SPICAV UV stellar occultation experiment which took place onboard ESA's Venus Express (VEX) orbiter in 2006-2014. The UV channel of SPICAV spectrometer detected absorption bands …
Locating dayside magnetopause reconnection with exhaust ion distributions
Fuselier, S. A.; Trattner, K. J.; Broll, J. M.
Magnetic reconnection at Earth's dayside magnetopause is essential to magnetospheric dynamics. Determining where reconnection takes place is important to understanding the processes involved, and many questions about reconnection location remain unanswered. We present a method for locating the magnetic reconnection X line at Earth's dayside magnet…