Search Publications

Microwave absorptivity by sulfuric acid in the Venus atmosphere: First results from the Venus Express Radio Science experiment VeRa
DOI: 10.1016/j.icarus.2012.09.029 Bibcode: 2012Icar..221..940O

Pätzold, M.; Bird, M. K.; Häusler, B. +5 more

The Venus Express (VEX) Radio Science experiment VeRa utilizes radio occultation techniques to investigate the Venus atmosphere over a wide range of latitudes. Radio attenuation measurements with the VEX 3.6 cm (X-band) signal provide information on the absorptivity distribution within the Venus cloud deck. The combined results from 6 years of occ…

2012 Icarus
VenusExpress 30
Nonlinear interaction between ring current protons and electromagnetic ion cyclotron waves
DOI: 10.1029/2012JA018088 Bibcode: 2012JGRA..11712217Z

Zhu, Hui; Su, Zhenpeng; Xiao, Fuliang +4 more

Electromagnetic ion cyclotron (EMIC) waves have long been suggested to account for the rapid decay of ring current, which is usually described by the quasi-linear theory. We demonstrate that the interactions between ring current protons and typical EMIC waves can be highly nonlinear. A dimensionless parameterRis derived to identify the nonlinear i…

2012 Journal of Geophysical Research (Space Physics)
Cluster 30
Discovery of Crystallized Water Ice in a Silhouette Disk in the M43 Region
DOI: 10.1088/0004-637X/753/1/19 Bibcode: 2012ApJ...753...19T

Tokunaga, Alan T.; Terada, Hiroshi

We present the 1.9-4.2 µm spectra of the five bright (L <= 11.2) young stars associated with silhouette disks with a moderate to high inclination angle of 39°-80° in the M42 and M43 regions. The water ice absorption is seen toward d121-1925 and d216-0939, while the spectra of d182-316, d183-405, and d218-354 show no water ice feature arou…

2012 The Astrophysical Journal
eHST 30
High frame rate imaging based photometry. Photometric reduction of data from electron-multiplying charge coupled devices (EMCCDs)
DOI: 10.1051/0004-6361/201219059 Bibcode: 2012A&A...542A..23H

Grundahl, F.; Jørgensen, U. G.; Harpsøe, K. B. W. +1 more

Context. The EMCCD is a type of CCD that delivers fast readout times and negligible readout noise, making it an ideal detector for high frame rate applications which improve resolution, like lucky imaging or shift-and-add. This improvement in resolution can potentially improve the photometry of faint stars in extremely crowded fields significantly…

2012 Astronomy and Astrophysics
eHST 29
Titan's Transport-driven Methane Cycle
DOI: 10.1088/2041-8205/756/2/L26 Bibcode: 2012ApJ...756L..26M

Mitchell, Jonathan L.

The mechanisms behind the occurrence of large cloud outbursts and precipitation on Titan have been disputed. A global- and annual-mean estimate of surface fluxes indicated only 1% of the insolation, or ~0.04 W m-2, is exchanged as sensible and/or latent fluxes. Since these fluxes are responsible for driving atmospheric convection, it ha…

2012 The Astrophysical Journal
Cassini 29
Strong interactions between g- and p-modes in the hybrid γ Doradus-δ Scuti CoRoT star ID 105733033
DOI: 10.1051/0004-6361/201117540 Bibcode: 2012A&A...540A.117C

Mathias, P.; Debosscher, J.; Chapellier, E. +2 more

Context. The presence of stellar p- and g-modes allows us to test stellar structure models in great detail from the core to the envelope. As the driving mechanisms are not yet fully understood, the first important step is to provide clear evidence of these pulsation modes.
Aims: Recent space missions have confirmed that the γ Doradus and the …

2012 Astronomy and Astrophysics
CoRoT 29
First Science Observations with SOFIA/FORCAST: Properties of Intermediate-luminosity Protostars and Circumstellar Disks in OMC-2
DOI: 10.1088/2041-8205/749/2/L24 Bibcode: 2012ApJ...749L..24A

Morris, Mark R.; Fischer, William J.; Calvet, Nuria +18 more

We examine eight young stellar objects in the OMC-2 star-forming region based on observations from the SOFIA/FORCAST early science phase, the Spitzer Space Telescope, the Herschel Space Observatory, Two Micron All Sky Survey, Atacama Pathfinder Experiment, and other results in the literature. We show the spectral energy distributions (SED) of thes…

2012 The Astrophysical Journal
Herschel 29
Modeling Space Plasma Dynamics with Anisotropic Kappa Distributions
DOI: 10.1007/978-3-642-30442-2_12 Bibcode: 2012ASSP...33...97L

Schlickeiser, R.; Pierrard, V.; Lazar, M. +1 more

Space plasmas are collisionpoor and kinetic effects prevail leading to wave fluctuations, which transfer the energy to small scales: wave-particle interactions replace collisions and enhance dispersive effects heating particles and producing suprathermal populations observed at any heliospheric distance in the solar wind. At large distances collis…

2012 Multi-scale Dynamical Processes in Space and Astrophysical Plasmas
Cluster 29
Correlations in the (Sub)millimeter Background from ACT × BLAST
DOI: 10.1088/0004-637X/744/1/40 Bibcode: 2012ApJ...744...40H

Hilton, Matt; Hasselfield, Matthew; Bond, J. Richard +43 more

We present measurements of the auto- and cross-frequency correlation power spectra of the cosmic (sub)millimeter background at 250, 350, and 500 µm (1200, 860, and 600 GHz) from observations made with the Balloon-borne Large Aperture Submillimeter Telescope (BLAST); and at 1380 and 2030 µm (218 and 148 GHz) from observations made with …

2012 The Astrophysical Journal
AKARI 29
The infrared dust bubble N22: an expanding H ii region and the star formation around it
DOI: 10.1051/0004-6361/201218861 Bibcode: 2012A&A...544A..39J

Esimbek, J.; Wu, G.; Ji, W. -G. +3 more


Aims: To increase the observational samples of star formation around expanding H ii regions, we analyzed the interstellar medium and star formation around N22.
Methods: We used data extracted from the seven large-scale surveys from infrared to radio wavelengths. In addition we used the JCMT observations of the J = 3-2 line of 12

2012 Astronomy and Astrophysics
AKARI 29