Search Publications
Variation of solar oscillation frequencies in solar cycle 23 and their relation to sunspot area and number
Hill, F.; Fletcher, L.; Jain, K. +3 more
Aims: Studying the long term evolution of the solar acoustic oscillations is necessary for understanding how the large-scale solar dynamo operates. In particular, an understanding of the solar cycle variation in the frequencies of solar oscillations can provide a powerful diagnostic tool for constraining various dynamo models. In this work, w…
The extra red plutino (55638) 2002 VE95
Barucci, M. A.; Fornasier, S.; Dotto, E. +7 more
Aims: In the framework of a large program, we observed (55638) 2002 VE95 with the ESO-VLT telescope to better constrain its surface composition and to investigate the possible heterogeneity of the surface.
Methods: We report new near-infrared observations performed in 2007 and 2008. Using the new constraints of the albedo obta…
Interstellar reddening towards six small areas in Puppis-Vela
Franco, G. A. P.
Context. The line-of-sight towards Puppis-Vela contains some of the most interesting and elusive objects in the solar neighbourhood, including the Gum nebula, the IRAS Vela shell, the Vela SNR, and dozens of cometary globules.
Aims: We investigate the distribution of the interstellar dust towards six small volumes of the sky in the region of …
A SOHO/UVCS study of coronal outflows at the edge of an active region complex
Poletto, G.; Zangrilli, L.
Context. In the past, active regions (ARs) have been suggested as a possible source of the slow solar wind. Their role as solar wind contributors has recently been supported by HINODE observations at low coronal levels.
Aims: Our purpose is to determine whether outflows at the edges of ARs can be detected in higher layers of the corona, suppo…
IGR J12319-0749: evidence for another extreme blazar found with INTEGRAL
Masetti, N.; Gehrels, N.; Bird, A. J. +6 more
We report on the identification of a new soft gamma-ray source, IGR J12319-0749, detected with the IBIS imager on board the INTEGRAL satellite. The source, which has an observed 20-100 keV flux of ~8.3 × 10-12 erg cm-2 s-1, is spatially coincident with an active galactic nucleus (AGN) at redshift z = 3.12. The broa…
Comparison between observed and theoretical O IV line ratios in the UV/EUV solar spectrum as derived by SUMER, CDS and EIS
Fludra, A.; Summers, H. P.; Giunta, A. S. +1 more
Aims: The joint use of SoHO Solar Ultraviolet Measurement of Emitted Radiation (SUMER), Coronal Diagnostic Spectrometer (CDS) and Hinode Extreme-ultraviolet Imaging Spectrometer (EIS) allow observation of several O iv line ratios, useful for temperature plasma diagnostics. Accurate atomic data are required to avoid interpretation errors in de…
The Planck SZ Cluster Catalog: expected X-ray properties
Bartlett, J. G.; Chamballu, A.; Melin, J. -B.
Surveys based on the Sunyaev-Zel'dovich (SZ) effect provide a fresh view of the galaxy cluster population, one that is complementary to X-ray surveys. To better understand the relation between these two kinds of survey, we construct an empirical cluster model using scaling relations constrained by current X-ray and SZ data. We apply our model to p…
Spectro-polarimetry of the bright side of Saturn's moon Iapetus
Tozzi, G. P.; Boehnhardt, H.; Ejeta, C. +1 more
Context. Measurements of the polarized reflected sunlight from atmosphereless solar system bodies, over a range of phase angles, provide information about the surface structure and composition.
Aims: With this work, we provide analysis of the polarimetric observations of the bright side of Iapetus at five different phase angles, and over the …
Super-resolution in map-making based on a physical instrument model and regularized inversion. Application to SPIRE/Herschel
Abergel, A.; Rodet, T.; Orieux, F. +3 more
We investigate super-resolution methods for image reconstruction from data provided by a family of scanning instruments like the Herschel observatory. To do this, we constructed a model of the instrument that faithfully reflects the physical reality, accurately taking the acquisition process into account to explain the data in a reliable manner. T…
A wide-field near-infrared H2 2.122 µm line survey of the Braid Nebula star formation region in Cygnus OB7
Smith, M. D.; Davis, C. J.; Beck, T. L. +8 more
Context. Outflows and jets are the first signposts of ongoing star formation processes in any molecular cloud, yet their study in optical bands provides limited results due to the large extinction present. Near-infrared unbiased wide-field observations in the H2 1-0 S(1) line at 2.122 µm alleviates the problem, enabling us to dete…