Search Publications
New method for determining central axial orientation of flux rope embedded within current sheet using multipoint measurements
Chen, Tao; Li, ZhaoYu; Yan, GuangQing
A new method for determining the central axial orientation of a two-dimensional coherent magnetic flux rope (MFR) via multipoint analysis of the magnetic-field structure is developed. The method is devised under the following geometrical assumptions: (1) on its cross section, the structure is left-right symmetric; (2) the projected structure veloc…
Detailed study of SNR G306.3-0.9 using XMM-Newton and Chandra observations
Miceli, M.; Combi, J. A.; García, F. +3 more
Aims: We aim to study the spatial distribution of the physical and chemical properties of the X-ray emitting plasma of the supernova remnant (SNR) G306.3-0.9 in detail to obtain constraints on its ionization stage, the progenitor supernova explosion, and the age of the remnant.
Methods: We used combined data from XMM-Newton and Chandra o…
A new terminal guidance sensor system for asteroid intercept or rendezvous missions
Lyzhoft, Joshua; Basart, John; Wie, Bong
This paper presents the initial conceptual study results of a new terminal guidance sensor system for asteroid intercept or rendezvous missions, which explores the use of visual, infrared, and radar devices. As was demonstrated by NASA's Deep Impact mission, visual cameras can be effectively utilized for hypervelocity intercept terminal guidance f…
Modelling the Interior Structure of Enceladus Based on the 2014's Cassini Gravity Data
Taubner, R. -S.; Leitner, J. J.; Firneis, M. G. +1 more
We present a model for the internal structure of Saturn's moon Enceladus. This model allows us to estimate the physical conditions at the bottom of the satellite's potential subsurface water reservoir and to determine the radial distribution of pressure and gravity. This leads to a better understanding of the physical and chemical conditions at th…
XMM-Newton studies of the supernova remnant G350.0-2.0
Shternin, P.; Zyuzin, D.; Danilenko, A. +2 more
We report the results of XMM-Newton observations of the Galactic mixed-morphology supernova remnant G350.0-2.0. Diffuse thermal X-ray emission fills the north-western part of the remnant surrounded by radio shell-like structures. We did not detect any X-ray counterpart of the latter structures, but found several bright blobs within the diffuse emi…
Assessment of Models of Galactic Thermal Dust Emission Using COBE/FIRAS and COBE/DIRBE Observations
Kogut, A.; Odegard, N.; Chuss, D. T. +1 more
Accurate modeling of the spectrum of thermal dust emission at millimeter wavelengths is important for improving the accuracy of foreground subtraction for cosmic microwave background (CMB) measurements, for improving the accuracy with which the contributions of different foreground emission components can be determined, and for improving our under…
Interplanetary magnetic field structure at Saturn inferred from nanodust measurements during the 2013 aurora campaign
Kempf, S.; Kurth, W. S.; Postberg, F. +3 more
Interactions between the solar wind and planetary magnetospheres provide important diagnostic information about the magnetospheric dynamics. The lack of monitoring of upstream solar wind conditions at the outer planets, however, restrains the overall scientific output. Here we apply a new method, using Cassini nanodust stream measurements, to deri…
Utilizing Synthetic UV Spectra to Explore the Physical Basis for the Classification of Lambda Boötis Stars
Cheng, Kwang-Ping; Tarbell, Erik S.; Neff, James E. +6 more
Lambda Boo-type stars are a group of late B to early F-type Population I dwarfs that show mild to extreme deficiencies of iron-peak elements (up to 2 dex), but their C, N, O, and S abundances are near solar. This intriguing stellar class has recently regained the spotlight because of the directly imaged planets around a confirmed Lambda Boo star, …
Reconstructing merger timelines using star cluster age distributions: the case of MCG+08-11-002
Kewley, Lisa J.; Davies, Rebecca L.; U, Vivian +3 more
We present near-infrared imaging and integral field spectroscopy of the centre of the dusty luminous infrared galaxy merger MCG+08-11-002, taken using the Near InfraRed Camera 2 (NIRC2) and the OH-Suppressing InfraRed Imaging Spectrograph (OSIRIS) on Keck II. We achieve a spatial resolution of ∼25 pc in the K band, allowing us to resolve 41 star c…
Eclipsing the innermost accretion disc regions in AGN
Miniutti, G.; Dovčiak, M.; Sanfrutos, M. +1 more
Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with the broad line region (BLR) (short timescales). In the latter, the cloud size has been estimated to be of the…