Search Publications
Sub-arcsecond radio and optical observations of the likely counterpart to the gamma-ray source 2FGL J2056.7+4939
Luque-Escamilla, P. L.; Martí, J.; Muñoz-Arjonilla, A. J. +1 more
We have searched and reviewed all multi-wavelength data available for the region towards the gamma-ray source 2FGL J2056.7+4939 in order to constrain its possible counterpart at lower energies. As a result, only a point-like optical/infrared source with flat-spectrum radio emission is found to be consistent with all X-ray and gamma-ray error circl…
X-Ray Spectral Study of AGN Sources Content in Some Deep Extragalactic XMM-Newton Fields
Misra, R.; Hassan, M. A.; Korany, B. A. +3 more
We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure time more than 60 ksec, had data from the EPIC-pn detector in the full-Frame mode and lying at high galactic lat…
Hydrogen ENA-cloud observation and modeling as a tool to study star-exoplanet interaction
Holmström, M.; Lammer, H.; Khodachenko, M. L. +2 more
During the previous years spacecraft observations of so-called Energetic Neutral Atoms (ENAs) have become an important remote-sensing technique in planetary science for analyzing the solar wind plasma flow around the upper atmospheric environments of Solar System bodies. ENAs are produced whenever solar- or stellar wind protons interact via charge…
Analysis of periodic orbits in the Saturn-Titan system using the method of Poincare section surfaces
Safiya Beevi, A.; Sharma, R. K.
We explore the periodic orbits and the regions of quasi-periodic motion around both the primaries in the Saturn-Titan system in the framework of planar circular restricted three-body problem. The location, nature and size of periodic and quasi-periodic orbits are studied using the numerical technique of Poincare surface of sections. The maximum am…
Identification of new silicate carbon stars
Chen, Pei-Sheng; Shan, Hong-Guang
IRAS low-resolution spectra for 17 sources are presented in this paper. Together with the carbon star catalog, information from recent literatures, the ISO observation and the IRAS two-color diagram, it is found that among them 5 sources are new silicate carbon stars, 5 sources are candidates of silicate carbon stars and other 7 sources are probab…
About the measurements of the hard X-ray background
Pozanenko, A. S.; Bisnovatyi-Kogan, G. S.
We analyze uncertainties in the cosmic X-ray background measurements performed by the INTEGRAL observatory. We find that the most important effect limiting the accuracy of the measurements is related to the intrinsic background variation in detectors. Taking into account all of the uncertainties arising during the measurements we conclude that the…
Open issues on the synthesis of evolved stellar populations at ultraviolet wavelengths
Chavez, Miguel; Bertone, Emanuele
In this paper we briefly review three topics that have motivated our (and others') investigations in recent years within the context of evolutionary population synthesis techniques. These are: The origin of the FUV up-turn in elliptical galaxies, the age-metallicity degeneracy, and the study of the mid-UV rest-frame spectra of distant red galaxies…
A systematic cross-search for radio/infrared counterparts of XMM- Newton sources
Combi, J. A.; Luque-Escamilla, P. L.; Romero, G. E. +7 more
We present a catalog of cross-correlated radio, infrared and X-ray sources using a very restrictive selection criteria with an IDL-based code developed by us. The significance of the observed coincidences was evaluated through Monte Carlo simulations of synthetic sources following a well-tested protocol. We found 3320 coincident radio/X-ray source…
Statistical properties of the GALEX spectroscopic stellar sample
Chavez, Miguel; Bertone, Emanuele
The GALEX General Data Release 4/5 includes 174 spectroscopic tiles, obtained from slitless grism observations, for a total of more than 60 000 ultraviolet spectra. We have determined statistical properties of the sample of GALEX stars. We have defined a suitable system of spectroscopic indices, which measure the main mid-UV features at the GALEX …
The coronal mass ejection associated with the loop eruption and coronal dimmings on 2009 December 13
Yang, L. H.; Zheng, Ruisheng; Jiang, Y. C. +1 more
By using the multi-wavelength observations from the Solar Terrestrial Relations Observatory (STEREO), the Solar and Heliospheric Observatory (SOHO), the Transition Region and Coronal Explorer (TRACE) and the HINODE, we study a coronal mass ejection (CME) and associated coronal dimming occurred on 2009 December 13, as a consequence of the expansion…