Search Publications
Winds on Titan from ground-based tracking of the Huygens probe
Plettemeier, D.; Bird, M. K.; Asmar, S. W. +14 more
Large radio telescopes on Earth tracked the radio signal transmitted by the Huygens probe during its mission at Titan. Frequency measurements were conducted as a part of the Huygens Doppler Wind Experiment (DWE) in order to derive the velocity of the probe in the direction to Earth. The DWE instrumentation on board Huygens consisted of an ultrasta…
Cassini thermal observations of Saturn's main rings: Implications for particle rotation and vertical mixing
Altobelli, Nicolas; Michael Flasar, F.; Cuzzi, Jeffrey N. +9 more
In late 2004 and 2005 the Cassini composite infrared spectrometer (CIRS) obtained spatially resolved thermal infrared radial scans of Saturn's main rings (A, B and C, and Cassini Division) that show ring temperatures decreasing with increasing solar phase angle, α, on both the lit and unlit faces of the ring plane. These temperature differences su…
A Quantitative Study on Magnetic Configuration for Active Regions
Guo, Juan; Zhang, Hongqi; Chumak, Oleg V. +1 more
As compared with the Mount Wilson Magnetic Classification (MWMC), effective distance (dE) is a useful parameter because it gives a quantitative measure of magnetic configuration in active regions. We have analyzed magnetograms of 24 active regions of different types with MWMC. We have studied the evolution of magnetic fields of five act…
The Evolution of Rest-Frame K-Band Properties of Early-Type Galaxies from z = 1 to the Present1,
Rix, H. -W.; van der Wel, A.; Illingworth, G. D. +3 more
We measure the evolution of the rest-frame K-band fundamental plane from z=1 to the present by using IRAC imaging of a sample of early-type galaxies in the Chandra Deep Field-South at z~1 with accurately measured dynamical masses. We find that M/LK evolves as Δln(M/LK)=(-1.18+/-0.10)z, which is slower than in the B band [Δln(…
Hidden Trigger for the Giant Starburst Arc in M83?
Mediavilla, Evencio; Díaz, Rubén J.; Dottori, Horacio +3 more
The huge star formation events that occur at some galactic centers do not provide enough clues as to their origin, since the morphological signatures of the triggering mechanism are smeared out in the timescale of a few orbital revolutions of the galaxy core. Our high spatial resolution three-dimensional near-infrared spectroscopy for the first ti…
The H I Content of E+A Galaxies
Dejonghe, H.; Pisano, D. J.; Freeman, K. +3 more
We present deep single-dish H I observations of a sample of six nearby E+A galaxies (0.05<z<0.1). A nonnegligible fraction of a local sample of E+As are detected in H I. In four galaxies, we have detected up to a few times 109 Msolar of neutral gas. These E+A galaxies are almost as gas-rich as spiral galaxies with compa…
The Tully-Fisher relation of intermediate redshift field and cluster galaxies from Subaru spectroscopy
Milvang-Jensen, B.; Aragón-Salamanca, A.; Bamford, S. P. +3 more
We have carried out spectroscopic observations in four cluster fields using Subaru's FOCAS multislit spectrograph and obtained spectra for 103 bright disc field and cluster galaxies at 0.06 <=z<= 1.20. 77 of these show emission lines, and 33 provide reasonably secure determinations of the galaxies' rotation velocity. The rotation velocities,…
Ion escape at Mars: Comparison of a 3-D hybrid simulation with Mars Express IMA/ASPERA-3 measurements
Coates, A. J.; Kallio, E.; Fedorov, A. +44 more
We have analysed ion escape at Mars by comparing ASPERA-3/Mars Express ion measurements and a 3-D quasi-neutral hybrid model. As Mars Express does not have a magnetometer onboard, the analysed IMA data are from an orbit when the IMF clock angle was possible to determine from the magnetic field measurements of Mars Global Surveyor. We found that fa…
Density Diagnostics of the Hot Plasma in AE Aquarii with XMM-Newton
Ishida, Manabu; Kunieda, Hideyo; Okada, Shunsaku +1 more
We report on XMM-Newton observations of the magnetic CV AE Aqr. High-resolution spectroscopy of the He-like triplet of N and O with the RGS has enabled us to measure the electron number density of the plasma as ~1011 cm-3. Incorporating this with the emission measure, we estimate the geometrical scale of the plasma emitting t…
Subarcsecond-Resolution Radio Maps of Nearby Spiral Galaxies
Meier, David S.; Turner, Jean L.; Beck, Sara C. +3 more
We report subarcsecond-resolution Very Large Array imaging of four nearby spiral galaxies: IC 342, Maffei II, NGC 2903, and NGC 6946. In each galaxy, compact radio continuum sources are identified in the central ~15''×15'' region. These compact sources are responsible for 20%-30% of the total emission from the central kilopar…