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The Orbit and Albedo of Trans-Neptunian Binary (58534) 1997 CQ29
Noll, Keith S.; Stephens, Denise C.; Grundy, Will M. +2 more
We have measured the separations and position angles of the two components of the binary trans-Neptunian object (58534) 1997 CQ29 at eight epochs. From these data we are able to constrain the orbit and mass of this binary system. The best-fitting orbit has an orbital period of P=312+/-3 days. The orbital eccentricity is e=0.45+/-0.03 an…
Oscillations in the Umbral Atmosphere
Foley, C. R.; Fredvik, T.; Kjeldseth-Moe, O. +2 more
The results of simultaneous observations of oscillations in the chromosphere, transition region, and corona above nine sunspots are presented. The data are obtained through coordinated observing with the Solar and Heliospheric Observatory — SOHO and the Transition Region And Coronal Explorer — TRACE. Oscillations are detected above each umbra. The…
XMM-Newton EPIC and Optical Monitor observations of Her X-1 over the 35-d beat period
Hailey, Charles J.; Ramsay, Gavin; Zane, Silvia +2 more
We present the results of a series of XMM-Newton European Photon Imaging Camera (EPIC) and Optical Monitor observations of Her X-1, spread over a wide range of the 35-d precession period. We confirm that the spin modulation of the neutron star is weak or absent in the low state - in marked contrast to the main or short-on states. During the states…
Recent advances in the long-wavelength radio physics of the Sun
Gopalswamy, N.
Solar radio bursts at long wavelengths provide information on solar disturbances such as coronal mass ejections (CMEs) and shocks at the moment of their departure from the Sun. The radio bursts also provide information on the physical properties (density, temperature and magnetic field) of the medium that supports the propagation of the disturbanc…
Iron line spectroscopy of NGC 4593 with XMM-Newton: where is the black hole accretion disc?
Kaiser, Mary Elizabeth; Brenneman, Laura W.; Wilms, Jörn +1 more
We present an analysis of the 2-10 keV XMM-Newton/EPIC-pn spectrum of the Seyfert-1 galaxy NGC 4593. Apart from the presence of two narrow emission lines corresponding to the Kα lines of cold and hydrogen-like iron, this spectrum possesses a power-law form to within ~3-5 per cent. There is a marked lack of spectral features from the relativistic r…
Flow shear near the boundary of the plasma sheet observed by Cluster and Geotail
Balogh, A.; RèMe, H.; Fazakerley, A. N. +13 more
We report on the transient strong flow shear (large northward/southward electric field) events accompanied by energetic ion beams and localized field-aligned currents observed at the boundary of the premidnight plasma sheet by Cluster in the Northern Hemisphere and Geotail in the Southern Hemisphere. The events took place associated with plasma sh…
XMM-Newton confirmation of a warm absorber in the z= 4.4 blazar PMN J0525-3343
Iwasawa, K.; Fabian, A. C.; Celotti, A. +2 more
We present the analysis and results from a series of XMM-Newton observations of the distant blazar PMN J0525-3343 at a redshift of 4.4. The X-ray spectrum shows a spectral flattening below ~1 keV, confirming earlier results from ASCA and BeppoSAX. The spectrum is well fitted by a power-law continuum with either a spectral break or absorption; no s…
A young binary brown dwarf in the R-CrA star formation region
Demarco, R.; Martín, E. L.; Bouy, H. +5 more
We present imaging and spectroscopic observations with HST (WFPC2, ACS/HRC and STIS), VLT (FORS2) and Keck (HIRES) of the dM 8 ultra-cool dwarf
Period-luminosity relations for Galactic Cepheid variables with independent distance measurements
Ngeow, Chow-Choong; Kanbur, Shashi M.
In this paper, we derive the period-luminosity (PL) relation for Galactic Cepheids with recent independent distance measurements from open cluster, Barnes-Evans surface brightness, interferometry and Hubble Space Telescope astrometry techniques. Our PL relation confirms the results from recent works, which showed that the Galactic Cepheids follow …
XMM-Newton spectral and timing analysis of the faint millisecond pulsars PSR J0751+1807 and PSR J1012+5307
Kramer, M.; Webb, N. A.; Barret, D. +3 more
We present XMM-Newton MOS imaging and PN timing data of the faint millisecond pulsars