Search Publications
A relation between circumnuclear H I, dust, and optical cores in low-power radio galaxies
Morganti, R.; Oosterloo, T.; van Moorsel, G. +1 more
From new observations and literature data we investigate the presence of H I, dust, and optical cores in the central kiloparsec of low-power radio galaxies. The goal of this pilot study is to identify physical relations between these components, which can help us to study kinematics and feeding mechanisms in future samples of active galaxies. Our …
IGR J18179-1621: an obscured X-ray pulsar discovered by INTEGRAL
Ferrigno, C.; Bozzo, E.; Falanga, M. +2 more
We report on all the INTEGRAL and Swift data collected during the first outburst observed from IGR J18179-1621. The broad-band spectral analysis showed that the X-ray emission from the source is heavily absorbed (NH ≃ 1023 cm-2), and well-described by a flat power-law with a high energy rollover (cutoff energy 9-12…
Implications of the radio spectral index transition in LS I +61°303 for its INTEGRAL data analysis
Zimmermann, L.; Massi, M.
Context. The TeV emitting X-ray binary LS I +61°303 has two radio periodicities that correspond to a large periodic outburst with the same period as the orbit, 26.5 days (phase Φ), and a second periodicity of 1667 days (phase Θ), which modulates the orbital phase and amplitude of the large outburst. Analyses of the radio spectral index revealed in…
Variable stars in the globular cluster M 28 (NGC 6626)
Contreras Ramos, R.; Catelan, M.; Alonso-García, J. +3 more
Context. We present a new search for variable stars in the Galactic globular cluster M 28 (NGC 6626).
Aims: The search is based on a series of BVI images obtained with the SMARTS Consortium's 1.3 m telescope at Cerro Tololo Inter-American Observatory, Chile.
Methods: The search was carried out using the ISIS v2.2 image subtraction packag…
Testing spectropolarimetry in the extreme ultraviolet to infer the solar coronal magnetic field
Khan, A.
Context. Spectropolarimetry has the potential to provide us with important coronal plasma parameters.
Aims: We test spectropolarimetric forward modelling by investigating whether it is possible to reproduce the only linear polarisation measurement made for the optically thin 1032 Å UV O vi line detected by the Solar Ultraviolet Measurements o…
Coronal equatorial rotation during solar cycle 23: radial variation and connections with helioseismology
Giordano, S.; Mancuso, S.
Time-series observations of the O vi 1032 Å spectral line intensity provided by the UltraViolet Coronagraph Spectrometer (UVCS) telescope aboard the Solar and Heliospheric Observatory (SOHO) spacecraft have been analyzed to establish the rotational characteristics of the equatorial solar corona as a function of height and time during solar cycle 2…
HSTOF ENA observations and energetic ion distributions in the heliosheath
Hsieh, K. C.; Hilchenbach, M.; Czechowski, A.
Context. Launched in 1996, HSTOF on board SOHO was the first instrument to detect the energetic neutral atoms (ENA) from the heliosheath. After mid 2003, the field of view of HSTOF was restricted to the flank sectors of the heliosheath, in which region the energetic ion distributions are still unknown. Interpretation of these data requires underst…
Scales of the magnetic fields in the quiet Sun
Sainz Dalda, A.; López Ariste, A.
Context. The presence of a turbulent magnetic field in the quiet Sun has been unveiled observationally using different techniques. The magnetic field is quasi-isotropic and has field strengths weaker than 100 G. It is pervasive and may host a local dynamo.
Aims: We aim to determine the length scale of the turbulent magnetic field in the quiet…
INTEGRAL constraints on the Galactic hard X-ray background from the Milky Way anticenter
Sunyaev, R.; Krivonos, R.; Tsygankov, S. +3 more
We present results of a study of the Galactic ridge X-ray emission (GRXE) in hard X-rays with the IBIS telescope onboard INTEGRAL in the region near the Galactic anticenter (GA) at l = 155°. We assumed a conservative 2σ upper limit on the flux from the GA in the 25-60 keV energy band of 1.25 × 10-10 erg s-1 cm-2 (1…
Deprojected analysis of Abell 1835 observed with Chandra and compared with XMM-Newton
Chen, Y.; Li, C. K.; Jia, S. M. +3 more
Using a deprojection technique, we study the X-ray properties of the galaxy cluster Abell 1835 observed with Chandra, including temperature, abundance, electron density, gas mass fraction, and total mass. A comparison with the results without deprojection shows that the properties do not change much. When we compare the results with those of XMM-N…