Search Publications
A Study of the Low-Mass X-Ray Binary Dip Sources XB 1916 - 053, XB 1323 - 619, X 1624 - 490 and 4U 1746 - 371 Observed with INTEGRAL
Balman, Ş.
We detect dipping activity/modulations in the light curve of the four low-mass X-ray binaries in the 3-10 keV and 20-40 keV energy ranges. The spectral parameters derived from the fits to the International Gamma-Ray Astrophysics Laboratory data are consistent with hot coronal structures in these systems where we find a range of plasma temperatures…
X-ray Diagnostics of Thermal Conditions of the Hot Plasmas in the Centaurus Cluster
Fukazawa, Y.; Tamura, T.; Matsushita, K. +9 more
X-ray data of the Centaurus cluster, obtained with XMM-Newton for 45 ks, were analyzed. Deprojected EPIC spectra from concentric thin-shell regions were reproduced equally well by a single-phase plasma emission model, or by a two-phase model developed by ASCA, both incorporating cool (1.7-2.0 keV) and hot (~ 4 keV) plasma temperatures. However, EP…
Predictions of interplanetary shock arrivals at Earth: Dependence of forecast outcome on the input parameters
Dryer, M.; Fry, C. D.; Smith, Z. K. +1 more
Predictions of interplanetary shock arrivals at Earth are important to space weather because they are often followed by geomagnetic disturbances that disrupt human technologies. The success of numerical simulation predictions depends on the codes and on the inputs obtained from solar observations. The inputs are usually divided into the more slowl…
SN 1999ga: a low-luminosity linear type II supernova?
Smartt, S. J.; Altavilla, G.; Turatto, M. +11 more
Context: Type II-linear supernovae are thought to arise from progenitors that have lost most of their H envelope by the time of the explosion, and they are poorly understood because they are only occasionally discovered. It is possible that they are intrinsically rare, but selection effects due to their rapid luminosity evolution may also play an …
Oblique lower band chorus waves: Time shifts between discrete elements observed by the Cluster spacecraft
Gurnett, Donald A.; Chum, Jaroslav; Santolik, Ondrej +1 more
We report observations of remarkable frequency differences and time shifts between the corresponding elements of lower band chorus recorded by the four Cluster spacecraft at low magnetic latitudes on 20 January 2004. The Poynting flux measurements made by the Spatio-Temporal Analysis of Field Fluctuations (STAFF) instrument confirm that the chorus…
Variable Stars in the Large Magellanic Cloud Globular Cluster NGC 2257. I. Results Based on 2007-2008 B, V Photometry
Nemec, James M.; Walker, Alistair; Jeon, Young-Beom
The variable stars in the Large Magellanic Cloud star cluster NGC 2257 are reinvestigated using photometry (to ~20th mag) of over 400 new B, V CCD images taken with the CTIO 0.9 m telescope on 14 nights in 2007 December and 2008 January. New period searches have been made using two independent algorithms (CLEAN, Period04); the resultant periods of…
Comparative study of productivity of the Rosetta target Comet 67P/Churyumov-Gerasimenko
de Almeida, A. A.; Trevisan Sanzovo, D.; Sanzovo, G. C. +2 more
In an attempt to evaluate correlations between several properties of comets we report the results of a cometary research involving a criterious analysis of gas and dust mass production rates in Comets 67P/Churyumov-Gerasimenko (main target of Rosetta Mission), 1P/Halley, Hyakutake (C/1996 B2), and 46P/Wirtanen and make a comparison between them.
Coronal magnetic fields inferred from IR wavelength and comparison with EUV observations
Liu, Y.
Spectropolarimetry using IR wavelength of 1075 nm has been proved to be a powerful tool for directly mapping solar coronal magnetic fields including transverse component directions and line-of-sight component intensities. Solar tomography, or stereoscopy based on EUV observations, can supply 3-D information for some magnetic field lines in bright …
Polarization of Microwave Radio Emission of Flare-Producing Solar Active Regions
Bogod, Vladimir M.; Yasnov, Leonid V.
On the basis of our multiwavelength observations made with the one-dimensional RATAN-600 radio telescope, we study the inversion of the circular polarization in the solar microwave emission at different frequencies. The inversion is detected in the emission of flare-producing active regions (FPARs) at various stages of their development, starting …
Rest-Frame UV Versus Optical Morphologies of Galaxies Using Sérsic Profile Fitting: The Importance of Morphological K-Correction
Wadadekar, Yogesh; Rawat, Abhishek; De Mello, Duilia
We show a comparison of the rest-frame UV morphologies of a sample of 162 intermediate-redshift (z median = 1.02) galaxies with their rest-frame optical morphologies. We select our sample from the deepest near-UV image obtained with the Hubble Space Telescope (HST) using the Wide Field Planetary Camera 2 (WFPC2; F300W) as part of the pa…