Search Publications
X-Ray Observations and Infrared Identification of the Transient 7.8 s X-Ray Binary Pulsar XTE J1829-098
Gotthelf, E. V.; Halpern, J. P.
XMM-Newton and Chandra observations of the transient 7.8 s pulsar XTE J1829-098 are used to characterize its pulse shape and spectrum, and to facilitate a search for an optical or infrared counterpart. In outburst, the absorbed, hard X-ray spectrum with Γ=0.76+/-0.13 and NH=(6.0+/-0.6)×1022 cm-2 is typical of X-ray…
Broad-band X-ray spectrum of the newly discovered broad-line radio galaxy IGR J21247+5058
de Rosa, A.; Giroletti, M.; Bird, A. J. +7 more
In this paper, we present radio and high-energy observations of the INTEGRAL source IGR J21247+5058, a broad line emitting galaxy obscured by the Galactic plane. Archival Very Large Array radio data indicate that IGR J21247+5058 can be classified as an Faranoff-Riley type II Broad-Line Radio Galaxy. The spectrum between 610 MHz and 15 GHz is typic…
Prominence fine structures in a magnetic equilibrium. III. Lyman continuum in 2D configurations
Heinzel, P.; Anzer, U.; Gunár, S.
Aims:We discuss the behavior of the Lyman continuum profiles studied on the grid of 2D vertical-thread models for prominence fine structures.
Methods: Multilevel non-LTE transfer calculations for a 12-level plus continuum hydrogen model atom are used.
Results: Since the Lyman continuum is formed in regions with different temperatures for d…
Hidden activity in high-redshift spheroidal galaxies from mid-infrared and X-ray observations in the GOODS-North field
Rodighiero, G.; Fritz, J.; Franceschini, A. +6 more
We exploit very deep mid-infrared (MIR) and X-ray observations by Spitzer and Chandra in the GOODS-North field to identify signs of hidden [either starburst or active galactic nucleus (AGN)] activity in spheroidal galaxies between z ~= 0.3 and 1. Our reference is a complete sample of 168 morphologically classified spheroidal (elliptical/lenticular…
Unravelling the morphologies of luminous compact galaxies using the HST/ACS GOODS survey
Flores, H.; Hammer, F.; Rawat, A. +2 more
Context: Luminous Compact Galaxies (LCGs) (MB ≤ -20, R1/2 ≤ 4.5 kpc and EW0(OII) ≥ 15 Å) constitute one of the most rapidly evolving galaxy populations over the last ~8 Gyr history of the universe. Due to their inherently compact sizes, any detailed quantitative analysis of their morphologies has proved to be diffi…
Log-normal intensity distribution of the quiet-Sun FUV continuum observed by SUMER
Curdt, W.; Fontenla, J. M.; Avrett, E. H. +1 more
We analyse observations of the quiet-Sun far ultraviolet (FUV) continuum at various wavelengths near 1430 Å obtained by the SUMER instrument on SOHO. According to semi-empirical atmospheric models this continuum originates from the layers in the chromosphere where the temperature rises from low values at near-radiative equilibrium to a plateau of …
The Nearby Young Visual Binary HIP 115147 and Its Common Proper Motion Companion LSPM J2322+7847
Makarov, V. V.; Zacharias, N.; Hennessy, G. S. +2 more
We report a late M-type, common proper motion companion to a nearby young visual binary HIP 115147 (V368 Cep), separated by 963" from the primary K0 dwarf. This optically dim star was identified as a candidate high proper motion, nearby dwarf LSPM J2322+7847 by Lépine in 2005. The wide companion is one of the latest post-T Tauri low-mass stars fou…
Application of an XMM-Newton EPIC Monte Carlo Technique to Analysis and Interpretation of Data for the Abell 1689, RX J0658-55, and Centaurus Clusters of Galaxies
Peterson, J. R.; Madejski, G.; Andersson, K.
We propose a new Monte Carlo method to study extended X-ray sources with the European Photon Imaging Camera (EPIC) aboard XMM-Newton. The smoothed particle inference (SPI) technique, described in a companion paper, is applied here to the EPIC data for the clusters of galaxies Abell 1689, Centaurus, and RX J0658-55 (the ``bullet cluster''). We aim …
Mechanical disturbances in Fourier spectrometers
Formisano, Vittorio; Saggin, Bortolino; Comolli, Lorenzo
Fourier spectrometers are sensitive to many kinds of disturbance. This focus is mainly on those connected to mechanical vibrations, assessing the relationships between the mechanical inputs and the deriving effects on the spectra. Mechanical vibrations have two main effects on the spectra, the addition of signals due to direct sensitivity to vibra…
Density Dependence of the Mass Function of Globular Star Clusters in the Sombrero Galaxy and Its Dynamical Implications
Fall, S. Michael; Chandar, Rupali; McLaughlin, Dean E.
We have constructed the mass function of globular star clusters in the Sombrero galaxy in bins of different internal half-mass density ρh and projected galactocentric distance R. This is based on the published measurements of the magnitudes and effective radii of the clusters by Spitler and coworkers in BVR images taken with the ACS on …