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A new code for Fourier-Legendre analysis of large datasets: First results and a comparison with ring-diagram analysis
Thompson, M. J.; Roth, M.; Doerr, H. -P. +2 more
Fourier-Legendre decomposition (FLD) of solar Doppler imaging data is a promising method to estimate the sub-surface solar meridional flow. FLD is sensible to low-degree oscillation modes and thus has the potential to probe the deep meridional flow. We present a newly developed code to be used for large scale FLD analysis of helioseismic data as p…
Recent discoveries of supersoft X-ray sources in M 31
Stiele, H.; Pietsch, W.; Haberl, F. +9 more
Classical novae (CNe) have recently been reported to represent the major class of supersoft X-ray sources (SSSs) in the central area of our neighbouring galaxy M 31. This paper presents a review of results from recent X-ray observations of M 31 with XMM-Newton and Chandra. We carried out a dedicated optical and X-ray monitoring program of CNe and …
The Global Solar Wind Between 1 AU and the Termination Shock
Whang, Y. C.
This paper studies the global solar wind between 1 AU and the termination shock, taking into account the highly latitude dependent solar wind at the 1 AU boundary and the ionization of interstellar neutral hydrogen. A system of two-fluid magnetohydrodynamics equations governs the flow of solar wind plasma; the conditions of the solar wind at 1 AU …
Noise and Bias In Square-Root Compression Schemes
Rhodes, Jason; Bernstein, Gary M.; Bebek, Chris +3 more
We investigate data compression schemes for proposed all-sky diffraction-limited visible/NIR sky surveys aimed at the dark-energy problem. We show that lossy square-root compression to 1 bit pixel-1 of noise, followed by standard lossless compression algorithms, reduces the images to 2.5-4 bits pixel-1, depending primarily up…
Sub-surface Meridional Flow, Vorticity, and the Lifetime of Solar Active Regions
Maurya, R. A.; Ambastha, A.
Solar sub-surface fluid topology provides an indirect approach to examine the internal characteristics of active regions (ARs). Earlier studies have revealed the prevalence of strong flows in the interior of ARs having complex magnetic fields. Using the Doppler data obtained by the Global Oscillation Network Group project for a sample of 74 ARs, w…
Tomographic Reconstruction of the Three-dimensional Structure of the HH30 Jet
del Burgo, C.; De Colle, F.; Raga, A. C.
The physical parameters of Herbig-Haro (HH) jets are usually determined from emission-line ratios, obtained from spectroscopy or narrowband imaging, assuming that the emitting region is homogeneous along the line of sight. Under the more general hypothesis of axisymmetry, we apply tomographic reconstruction techniques to the analysis of HH jets. W…
Responses of the magnetotail plasma sheet to two interplanetary shocks: TC-1 observations
Zuo, PingBing; Liu, ZhenXing; Yao, Li +1 more
Two interplanetary shocks are examined to determine the responses of the magnetic field and plasma in the plasma sheet upon the shock impacts by using TC-1 observational data. The two shocks are observed by WIND on November 7, 2004. Prior to and after the shock, the IMF is either weakly southward or northward. The responses of the plasma sheet to …
Interfacial liquid water on Mars and its potential role in formation of hill and dune gullies
Markiewicz, Wojciech J.; Kossacki, Konrad J.
Gullies are among the most intriguing structures identified on the surface of Mars. Most common are gullies located on the slopes of craters which are probably formed by liquid water transported by shallow aquifers (Heldmann, J.L., Carlsson, E., Johansson, H., Mellon, M.T., Toon, O.B. [2007]. Icarus 188, 324-344). Two particular types of gullies a…
Young Stars in the Camelopardalis Dust and Molecular Clouds. VI. YSOs Verified by Spitzer and Akari Infrared Photometry
Straižys, V.; Kazlauskas, A.
Using photometric data of infrared surveys, young stellar object (YSO) status is verified for 141 objects selected in our previous papers in the Cassiopeia and Camelopardalis segment of the Milky Way bounded by Galactic coordinates (ℓ, b) = (132--158°, ±12°). The area includes the known star-forming regions in the emission nebulae W3, W4 and W5 an…
Discovery of a magnetic neutron star in X-ray transient IGR J01583+6713
Wang, W.
Aims: IGR J01583+6713 is a new transient source discovered by the INTEGRAL/IBIS hard X-ray surveys. Optical observations have provided evidence that it is a high mass X-ray binary, but its nature remains unclear.
Methods: We used the INTEGRAL/IBIS data to study IGR J01583+6713 during its outburst.
Results: We present the temporal pr…