Search Publications
On the origin and configuration of the 20 March 2003 interplanetary shock and magnetic cloud at 1 AU
Richardson, I. G.; Lepping, R. P.; Martin, S. F. +1 more
On 20 March 2003, a forward shock was observed in the near-Earth solar wind, followed 8 hours later by an interplanetary magnetic cloud (IMC), in a configuration having several uncommon features: Both were parts of a 38-hour interval containing transient solar outflows that occurred in an extended high-speed stream from a Y-shaped extension of the…
Nuclear Properties of Nearby Spiral Galaxies from Hubble Space Telescope NICMOS Imaging and STIS Spectroscopy
Marconi, A.; Capetti, A.; Carollo, C. M. +16 more
We investigate the central regions of 23 spiral galaxies using Space Telescope Imaging Spectrograph (STIS) spectroscopy and archival Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) imaging. The sample is taken from our program to determine the masses of central massive black holes (MBHs) in 54 nearby spiral galaxies. Stars are likely t…
Abundances in planetary nebulae: Mz 3
Pottasch, S. R.; Surendiranath, R.
ISO spectra of the bipolar planetary nebula
The near-UV pulse profile and spectrum of the pulsar PSR B0656+14
Sollerman, J.; Lundqvist, P.; Shibanov, Yu. A. +2 more
We have observed the middle-aged pulsar PSR B0656+14 with the prism and the NUV MAMA detector of the Space Telescope Imaging Spectrograph (STIS) to measure the pulsar spectrum and periodic pulsations in the near-ultraviolet (NUV). The pulsations are clearly detected, double-peaked and very similar to the optical pulse profile. The NUV pulsed fract…
XMM-Newton observations of UW CrB: detection of X-ray bursts and evidence for accretion disc evolution
Ramsay, Gavin; Mukai, Koji; Hakala, Pasi +4 more
UW CrB (MS 1603+2600) is a peculiar short-period X-ray binary that exhibits extraordinary optical behaviour. The shape of the optical light curve of the system changes drastically from night to night, without any changes in overall brightness. Here we report X-ray observations of UW CrB obtained with XMM-Newton. We find evidence for several X-ray …
Is the INTEGRAL IBIS Source IGR J17204-3554 a Gamma-Ray-emitting Galaxy Hidden behind the Molecular Cloud NGC 6334?
Gehrels, N.; Walter, R.; Bird, A. J. +9 more
We report on the identification of a soft gamma-ray source, IGR J17204-3554, detected with IBIS, the Imager on Board the INTEGRAL Satellite. The source has a 20-100 keV flux of ~3×10-11 ergs cm-2 s-1 and is spatially coincident with NGC 6334, a molecular cloud located in the Sagittarius arm of the Milky Way. Diffus…
Optical spectroscopy of X-Mega targets - V. The spectroscopic binary HD 93161 A and its visual companion HD 93161 B*
Gosset, E.; Nazé, Y.; Rauw, G. +2 more
We present the analysis of an extensive set of high-resolution spectroscopic observations of HD 93161, a visual binary with a separation of 2 arcsec. HD 93161 A is a spectroscopic binary, with both components clearly detected throughout the orbit. The primary star is most probably of spectral type O8V, while the secondary is likely an O9V. We obta…
Spectroscopy and stellar populations of star-forming galaxies at z ~ 3 in the Hubble Deep Field - South
Burgarella, D.; Inoue, A. K.; Iwata, I.
We present results of VLT/FORS2 spectroscopy of galaxies at z ∼ 3 in the Hubble Deep Field - South (HDF-S). A sample of galaxies was drawn from the photometric redshift catalogue based on the HST/WFPC2 optical images and the deep near-infrared images obtained with VLT/ISAAC as a part of the Faint Infrared Extragalactic Survey (FIRES) project. We s…
Proper Orthogonal Decomposition of Solar Photospheric Motions
Vecchio, A.; Carbone, V.; Veltri, P. +5 more
The spatiotemporal dynamics of the solar photosphere is studied by performing a proper orthogonal decomposition (POD) of line of sight velocity fields computed from high resolution data coming from the MDI/SOHO instrument. Using this technique, we are able to identify and characterize the different dynamical regimes acting in the system. Low-frequ…
Investigating ionized disc models of the variable narrow-line Seyfert 1 PG 1404+226
Brandt, W. N.; Fabian, A. C.; Boller, Th. +1 more
We investigate the use of relativistically blurred photoionized disc models on an XMM-Newton observation of the narrow-line Seyfert 1 galaxy PG 1404+226. The model is designed to reproduce the radiation from the inner accretion disc around a Kerr black hole, and is more successful at fitting the spectrum than models based on a thermal soft excess.…