Search Publications
A low luminosity state in the massive X-ray binary SAX J0635+0533
Mereghetti, S.; La Palombara, N.
The X-ray pulsar SAX J0635+0533 was repeatedly observed with the XMM-Newton satellite in 2003-2004. The precise localization provided by these observations confirms the association of SAX J0635+0533 with a Be star. The source was found, for the first time, in a low-intensity state, a factor ~30 lower than that seen in all previous observations. Th…
The evolution of cluster dwarfs
Harsono, D.; De Propris, R.
We summarize the results from analyzing six clusters of galaxies at 0.14 < z < 0.40 observed with the Hubble Space Telescope Advanced Camera for Surveys. We derive deep composite luminosity functions in B, g, V, r, i, and z down to absolute magnitude of ∼ -14 + 5 log h mag. The luminosity functions are fitted by a single Schechter function w…
Fresnel zone plate telescopes for X-ray imaging II: numerical simulations with parallel and diverging beams
Rao, A. R.; Girish, V.; Nandi, Anuj +4 more
We present the results of simulations of shadows cast by a zone plate telescope which may have one to four pairs of zone plates. From the shadows we reconstruct the images under various circumstances. We discuss physical basis of the resolution of the telescope and demonstrate this by our simulations. We allow the source to be at a finite distance…
On the predictability of unstable satellite motion around elongated celestial bodies
Mysen, E.
Context: Close satellite orbits around small and elongated celestial bodies can experience massive aperiodic changes in shape. According to a number of published works, the changes are continuous functions of the orbit elements of the satellite's unperturbed trajectory.
Aims: Later research, however, has revealed that the onset of instability …
Spatial and Spectral Behaviors of Solar Flares Observed in Microwaves
Cao, Wenda; Ning, Zongjun
The spatial and spectral behaviors of two solar flares observed by the Nobeyama Radioheliograph (NoRH) on 24 August 2002 and 22 August 2005 are explored. They were observed with a single loop-top source and double footpoint sources at the beginning, then with looplike structures for the rest of the event. NoRH has high spatial and temporal resolut…
Space projections on solar-terrestrial physics
Zelenyi, L. M.; Kuznetsov, V. D.
An overview of the current status of research in the field of solar-terrestrial physics conducted by space agencies of various countries is given. The main results of current (Ulysses, SOHO, TRACE, RHESSI, Hinode, and STEREO) and completed (Coronas-F and others) missions as well as the scientific goals and objectives of space projects being prepar…
Reconnection Hall current system observed in the magnetotail and in the ionosphere
Snekvik, K.; Østgaard, N.; Amm, O. +1 more
On 07 Sep 2001 around 21:40 UT, Cluster was located 19 R E downtail, and observed earthward fast flows and strong perturbations in the dawn-dusk component of the magnetic field (B Y ). The perturbations corresponded to a sheet of tailward field aligned current close to the neutral sheet and another sheet of earthward field…
A Repository of Precision Flat Fields for High-Resolution MDI Continuum Data
Potts, H. E.; Diver, D. A.
We describe an archive of high-precision MDI flat fields that can be used to refine most MDI high-resolution continuum data. The archive consists of many flat-field images representing different time ranges over the full operating period of SOHO. The residual flat-field error on the standard level 1.5/1.8 calibrated continuum images represents a s…
Diffuse 18µ Emission around TYC 3159-6-1 Discovered by the AKARI MIR All-Sky Survey
Oyabu, Shinki; Onaka, Takashi; Takita, Satoshi +11 more
We report on observations of the mysterious object TYC 3159-6-1 located toward the Cygnus X region. It shows interesting characteristics in the AKARI mid-infrared All-Sky Survey. The central star is clearly detected as a point source at 9µ, while no point-like source, but a large shell-like structure is seen around the source at 18µ. T…
Erratum: "Suzaku Observations of Local Ultraluminous Infrared Galaxies" (2009, ApJ, 691, 261)
Sanders, D. B.; Nakagawa, Takao; Veilleux, Sylvain +7 more
We report the results from our analysis of {\it Suzaku} XIS (0.5-10 keV) and HXD/PIN (15-40 keV) observations of five well-known local ULIRGs: {\em IRAS} F05189-2524, {\em IRAS} F08572+3915, Mrk 273, PKS 1345+12, and Arp 220. The XIS observations of F05189-2524 and Mrk 273 reveal strong iron lines consistent with Fe K$\alpha$ and changes in spectr…