Search Publications

G0.570-0.018: A Young Supernova Remnant? INTEGRAL and VLA Observations

Terrier, R.; Renaud, M.; Bykov, A. M. +4 more

We report INTEGRAL IBIS γ-ray and VLA radio observations of G0.570-0.018, a diffuse X-ray source recently discovered by ASCA and Chandra in the Galactic center region. Based on its spectrum and morphology, G0.570-0.018 has been proposed to be a very young supernova remnant. In this scenario, the presence of γ-ray lines coming from the short-lived …

The possible detection of high-redshift Type II QSOs in deep fields

Meiksin, Avery

The colours of high-redshift Type II quasi-stellar objects (QSOs) are synthesized from observations of moderate-redshift systems. It is shown that Type II QSOs are comparable to starbursts at matching the colours of z₈₅₀-dropouts and i₇₇₅-drops in the Hubble UltraDeep Field, and more naturally account for the bluest objects d…

Corrections of Proper Motions in Declination By Using ILS Data

Damljanovic, G.; Pejovic, N.

There are nowadays numerous astrometric ground--based observations of some stars referred to Hipparcos Catalogue, made at many observatories during the last century. We used the data on latitude variations, covering the period 1899.7 -- 1979.0, of visual Zenith Telescopes (ZT) of International Latitude Service (ILS), to improve the Hipparcos prope…

The Need for Ultraviolet to Understand the Chemical Evolution of the Universe and Cosmology.

Fabian, Andrew C.; Petitjean, Patrick; Fransson, Claes +8 more

We identify an important set of key areas where an advanced observational Ultraviolet capability would have major impact on studies of cosmology and Galaxy formation in the young Universe. Most of these are associated with the Universe at z < 3–4. We address the issues associated with Dark matter evidence in the local Universe and the impact of…

Simultaneous ground-based and satellite observations of Pc5 geomagnetic pulsations: A case study using multipoint measurements

Balogh, A.; Sung, S. -K.; Kim, K. -H. +5 more

Pc5 pulsations with a latitude-independent frequency of ∼2.8 mHz (period ∼6 min) were observed with ground-based magnetometers in the morning sector (0700–1000 local time) from 0730 to 0810 UT, April 29, 2001. The pulsations exhibited an amplitude peak and a ∼180° phase change at ∼67° geomagnetic latitude. A vortex structure of the equivalent iono…

Effective Length of a Receiving Antenna in a Streaming Plasma

Fiala, V.; Chugunov, Y. V.

A deep XMM-Newton serendipitous survey of a middle-latitude area

Caraveo, P. A.; Bignami, G. F.; de Luca, A. +4 more

The radio-quiet neutron star 1E1207.4-5209 was the target of a 260 ks XMM-Newton observation, that yielded, as a by product, a harvest of about 200 serendipitous X-ray sources above a limiting flux of 2 × 10^-15 erg cm^-2 s^-1 in the 0.3-8 keV energy range. In view of the intermediate latitude of our field (b≃ 10°), i…

Velocity Space of Galactic O-B Stars

Zhu, Zi

Based on the Hipparcos proper motions and available radial velocity data of O-B stars, we have re-examined the local kinematical structure of the young disk population of ~1500 O-B stars not including the Gould-belt stars. A systematic warping motion of the stars about the direction to the Galactic center has been reconfirmed. A negative K-term im…

Swift, RXTE, and INTEGRAL observation of Swift J1922.7-1716

Campana, S.; Belloni, T.; Falanga, M.

We report the results of analyzing Swift, RossiXTE, and INTEGRAL data of Swift J1922.7-1716, a likely transient X-ray source discovered by Swift/BAT. Both the fast variability measured by the RXTE/PCA and the combined Swift/XRT, RXTE/PCA, and INTEGRAL/ISGRI (0.5-100 keV) energy spectrum suggest that the system is a neutron-star low-mass X-ray bina…

On measuring the Tully-Fisher relation at z > 1. A case study using strong Hα emitting galaxies at z > 1.5

Yan, L.; van der Werf, P. P.; Moorwood, A. F. M. +1 more

The evolution of the line width - luminosity relation for spiral galaxies, the Tully-Fisher relation, strongly constrains galaxy formation and evolution models. At this moment, the kinematics of z>1 spiral galaxies can only be measured using rest frame optical emission lines associated with star formation, such as Hα and [O III]5007/4959 and [O…