Search Publications
The opacity of spiral galaxy disks. VII. The accuracy of galaxy counts as an extinction probe
Allen, Ronald J.; Holwerda, B. W.; van der Kruit, P. C. +1 more
The "Synthetic Field Method" (SFM) was introduced by González et al. (1998, ApJ, 506, 152) to calibrate numbers of distant galaxies as a probe of extinction in a foreground spiral disk. González et al. (2003, AJ, 125, 1182) studied the effect of the foreground disk on these numbers using simulations of current and future instruments for fields in …
Abundances in planetary nebulae: NGC 6886
Pottasch, S. R.; Surendiranath, R.
ISO and IUE spectra of the round-shaped planetary nebula
XMM-Newton discovery of soft X-ray absorption in the high-z superluminous Blazar RBS 315
Guainazzi, M.; Piconcelli, E.
We present the analysis and the results of a 20 ks XMM-Newton observation of the extremely X-ray loud (LX ≈ 5 × 1047 erg s-1) flat-spectrum radio quasar RBS 315 at a redshift of 2.69. This EPIC observation has allowed us to strongly constrain the slope of the continuum (Γ = 1.23±0.01) as well as to discover the pre…
Is Arcturus a well-understood K giant?. Test of model atmospheres and potential companion detection by near-infrared interferometry
Eriksson, K.; Decin, L.; Verhoelst, T. +8 more
We present near-IR interferometric measurements of the K1.5 giant Arcturus (α Bootis), obtained at the IOTA interferometer with the FLUOR instrument, in four narrow filters with central wavelengths ranging from 2.03 µm to 2.39 µm. These observations were expected to allow us to quantify the wavelength dependence of the diameter of a ty…
ADAS analysis of the differential emission measure structure of the inner solar corona. II. A study of the "quiet Sun" inhomogeneities from SOHO CDS-NIS spectra
Lanzafame, A. C.; Brooks, D. H.; Lang, J.
We present a study of the differential emission measure (DEM) of a “quiet Sun” area observed in the extreme ultraviolet at normal incidence by the Coronal Diagnostic Spectrometer (CDS) on the SOHO spacecraft. The data used for this work were taken using the NISATS observing sequence. This takes the full wavelength ranges from both the N…
The 3-D shaping of NGC 6741: A massive, fast-evolving Planetary Nebula at the recombination-reionization edge
Sabbadin, F.; Turatto, M.; Cappellaro, E. +2 more
We infer the gas kinematics, diagnostics and ionic radial profiles, distance and central star parameters, nebular photo-ionization model, spatial structure and evolutionary phase of the Planetary Nebula NGC 6741 by means of long-slit ESO NTT+EMMI high-resolution spectra at nine position angles, reduced and analysed according to the tomographic and…
The proper motion of the Magellanic Clouds: The UCAC2-Hipparcos inconsistency
Momany, Y.; Zaggia, S.
Using the USNO CCD Astrograph all-sky Catalog (UCAC2), we measure the mean proper motion of the two Magellanic Clouds. Appropriately-selected LMC populations show a proper motion <µα,µδ>≃(+0.84,+4.32) that is significantly higher, in <µδ>, than currently accepted Hipparcos-like values; <µα,µδ>≃(+1.94…
Determination of confusion noise for far-infrared measurements
Lemke, D.; Klaas, U.; Kiss, Cs.
We present a detailed assessment of the far-infrared confusion noise imposed on measurements with the ISOPHOT far-infrared detectors and cameras aboard the ISO satellite. We provide confusion noise values for all measurement configurations and observing modes of ISOPHOT in the 90 µm ≤ λ ≤ 200 µm wavelength range. Based on these results…
Out of the darkness: the infrared afterglow of the INTEGRAL burst GRB 040422 observed with the VLT
Covino, S.; D'Avanzo, P.; Campana, S. +15 more
Investigating the EGRET-radio galaxies link with INTEGRAL: The case of 3EG J1621+8203 and NGC 6251
Guainazzi, M.; Grenier, I. A.; Grandi, P. +10 more
The analysis of an INTEGRAL AO2 observation of the error contours of the EGRET source 3EG J1621+8203 is presented. The only source found inside the error contours for energies between 20 and 30 keV at 5σ detection significance is the FR I radio galaxy NGC 6251. This supports the identification of NGC 6251 with 3EG J1621+8203. The observed flux is …