Search Publications
Low surface brightness galaxies around the HDF-S. II. Distances and volume densities
Bomans, D. J.; Dettmar, R. -J.; Haberzettl, L.
Aims:With this study we aim at the spectroscopic verification of a photometrically selected sample of Low Surface Brightness (LSB) galaxy candidates in a field around the Hubble Deep Field-South (HDF-S). The sample helps to extend the parameter space for LSB galaxies to lower central surface brightnesses and to provide better estimates on the volu…
Using VO tools to investigate distant radio starbursts hosting obscured AGN in the HDF(N) region
Muxlow, T. W. B.; Beswick, R.; Walton, N. A. +16 more
Context: A 10-arcmin region around the Hubble Deep Field (North) contains 92 radio sources brighter than 40 µJy which are well-resolved by MERLIN+VLA at 0.2arcsec-2' resolution (average size ~1"). 55 of these have Chandra X-ray counterparts in the 2-Ms CDF(N) field including at least 17 with a hard X-ray photon index and high luminosity char…
IGR J17254-3257, a new bursting neutron star
Walter, R.; Lund, N.; Kuulkers, E. +6 more
Aims:The study of the observational properties of uncommonly long bursts from low luminosity sources is important when investigating the transition from a hydrogen - rich bursting regime to a pure helium regime and from helium burning to carbon burning as predicted by current burst theories. On a few occasions X-ray bursts have been observed with …
The interaction of a plasmoid with a loop-top kernel
Kołomański, S.; Karlický, M.
Aims:We study the interaction between a downward moving plasmoid and a loop-top kernel recognized in the 30 November 2000 flare. Such an interaction is predicted by some numerical models of solar flares.
Methods: Using X-ray observations from Yohkoh and GOES, EUV observations from SOHO, and radio observations from Ondřejov, we perform multi-wa…
An XMM-Newton study of hyper-luminous infrared galaxies
Carrera, F. J.; Panessa, F.; Ruiz, A.
Aims:Hyper-Luminous Infrared Galaxies (HLIRGs) are the most luminous persistent objects in the Universe. They exhibit extremely high star formation rates, and most of them seem to harbor an Active Galactic Nucleus (AGN). They are unique laboratories to investigate ultimate star formation, and its connection to super-massive black hole growth. X-ra…
Outflow velocity of the O+5 ions in polar coronal holes out to 5 R⊙
Antonucci, E.; Telloni, D.; Dodero, M. A.
The purpose of the paper is to extend the measurement of the kinetic temperature and outflow velocity of the oxygen ions in the outer corona above polar holes out to 5 R_⊙. An analytical model of the solar corona at the minimum of activity has been employed in order to synthesize the spectral line profiles to be fitted with the data: the kinetic t…
The XMM-Newton RGS spectrum of the high luminosity Seyfert 1 galaxy Markarian 509
Page, M. J.; Branduardi-Raymont, G.; Smith, R. A. N.
We present a detailed analysis of the soft X-ray spectrum of the Seyfert 1 galaxy Markarian 509 taken with the XMM-Newton Reflection Grating Spectrometer. An underlying power-law continuum and three warm absorber phases provide a good fit to the data along with a number of broad and narrow emission lines. Our three warm absorber phases each have d…
Are the E-type asteroids (2867) Steins, a target of the Rosetta mission, and NEA (3103) Eger remnants of an old asteroid family?
Barucci, M. A.; Fornasier, S.; Marzari, F. +2 more
Aims:We have investigated the spectral properties of the E-type asteroids 2867 Steins, a main belt object target of the Rosetta mission, and 3103 Eger, a near Earth asteroid. The strong spectral similarity between these two objects suggests a possible common origin in spite of their presently different orbits. We explore the possibility that Stein…
Atomic data for radioactive elements Ra I, Ra II, Ac I and Ac II and application to their detection in HD 101065 and HR 465
Quinet, P.; Fivet, V.; Yushchenko, A. V. +3 more
Radiative data for transitions of astrophysical interest in radioactive elements Ra I, Ra II, Ac I and Ac II have been computed using a semi-empirical relativistic Hartree-Fock approach including core polarization effects. Most of the oscillator strengths reported in the present paper are new. A possible detection of radium (Ra II) and actinium (A…
The exceptionally extended flaring activity in the X-ray afterglow of GRB 050730 observed with Swift and XMM-Newton
Troja, E.; Campana, S.; Tagliaferri, G. +27 more
Aims: We observed the high redshift (z = 3.969) GRB 050730 with Swift and XMM-Newton to study its prompt and afterglow emission.
Methods: We carried out a detailed spectral and temporal analysis of Swift and XMM-Newton observations.
Results: The X-ray afterglow of GRB 050730 was found to decline along with time with superimposed intense fl…