Search Publications
Intercomparison of the LASCO-C2, SECCHI-COR1, SECCHI-COR2, and Mk4 Coronagraphs
Vourlidas, Angelos; Lamy, Philippe; Frazin, Richard A. +5 more
In order to assess the reliability and consistency of white-light coronagraph measurements, we report on quantitative comparisons between polarized brightness [pB] and total brightness [B] images taken by the following white-light coronagraphs: LASCO-C2 on SOHO, SECCHI-COR1 and -COR2 on STEREO, and the ground-based MLSO-Mk4. The data for this comp…
The roles of charge exchange and dissociation in spreading Saturn's neutral clouds
Delamere, P. A.; Bagenal, F.; Fleshman, B. L. +1 more
Neutrals sourced directly from Enceladus's plumes are initially confined to a dense neutral torus in Enceladus's orbit around Saturn. This neutral torus is redistributed by charge exchange, impact/photodissociation, and neutral-neutral collisions to produce Saturn's neutral clouds. Here we consider the former processes in greater detail than in pr…
Dayside magnetic topology at the Earth's magnetopause for northward IMF
Lavraud, B.; Fuselier, S. A.; Trattner, K. J. +1 more
When the Interplanetary Magnetic Field is northward, magnetic reconnection occurs at the Earth's high latitude magnetopause in regions poleward of the Earth's magnetospheric cusps. Observations at the high latitude magnetopause appear to support reconnection poleward of both northern and southern hemisphere cusps, forming closed field lines in the…
Magnification by Galaxy Group Dark Matter Halos
Leauthaud, Alexie; Rhodes, Jason; Capak, Peter +6 more
We report on the detection of gravitational lensing magnification by a population of galaxy groups, at a significance level of 4.9σ. Using X-ray-selected groups in the COSMOS 1.64 deg2 field, and high-redshift Lyman break galaxies as sources, we measure a lensing-induced angular cross-correlation between the samples. After satisfying co…
Hot flow anomalies at Venus
Coates, A. J.; Barabash, S.; Zhang, T. L. +8 more
We present a multi-instrument study of a hot flow anomaly (HFA) observed by the Venus Express spacecraft in the Venusian foreshock, on 22 March 2008, incorporating both Venus Express Magnetometer and Analyzer of Space Plasmas and Energetic Atoms (ASPERA) plasma observations. Centered on an interplanetary magnetic field discontinuity with inward co…
The discrepancy in solar EUV-proxy correlations on solar cycle and solar rotation timescales and its manifestation in the ionosphere
Liu, Libo; Wan, Weixing; Chen, Yiding
This study investigates the correlations between SOHO/Solar EUV Monitor 26-34 nm EUV and the F10.7 and Mg II proxies on solar cycle (long-term) and solar rotation (short-term) timescales. The long-term components of EUV and proxies are well correlated, and the general relation between them can be captured by the 81 day averaged EUV and …
SPICAV IR acousto-optic spectrometer experiment on Venus Express
Bertaux, Jean-Loup; Korablev, Oleg; Reberac, A. +11 more
SPICAV IR, a part of SPICAV/SOIR suite on Venus Express, is a compact single pixel spectrometer for the spectral range of 0.65-1.7 µm based on acousto-optical tunable filter (AOTF) technology. SPICAV IR is derived from SPICAM IR operating on Mars Express, the first AOTF spectrometer in the deep space, and adapted for Venus atmosphere measure…
Dispersive Nature of High Mach Number Collisionless Plasma Shocks: Poynting Flux of Oblique Whistler Waves
Bale, S. D.; Krasnoselskikh, V.; Schwartz, S. J. +3 more
Whistler wave trains are observed in the foot region of high Mach number quasiperpendicular shocks. The waves are oblique with respect to the ambient magnetic field as well as the shock normal. The Poynting flux of the waves is directed upstream in the shock normal frame starting from the ramp of the shock. This suggests that the waves are an inte…
Herschel/SPIRE observations of the dusty disk of NGC 4244
Bianchi, S.; Dalcanton, J. J.; Baes, M. +7 more
We present Herschel/SPIRE images at 250, 350, and 500 µm of NGC 4244, a typical low-mass, disk-only and edge-on spiral galaxy. The dust disk is clumpy and shows signs of truncation at the break radius of the stellar disk. This disk coincides with the densest part of the Hi disk. We compare the spectral energy distribution (SED), including th…
Shocks, Seyferts, and the Supernova Remnant Connection: A Chandra Observation of the Circinus Galaxy
Hardcastle, M. J.; Croston, J. H.; Kraft, R. P. +4 more
We analyze new Chandra observations of the nearest (D = 4 Mpc) Seyfert 2 active galaxy, Circinus, and match them to pre-existing radio, infrared, and optical data to study the kpc-scale emission. The proximity of Circinus allows us to observe in striking detail the structure of the radio lobes, revealing for the first time edge-brightened emission…