Search Publications
Stellar archaeology: the evolving spectrum of FG Sagittae
Jeffery, C. S.; Schönberner, D.
Over an interval of 120 years, the extraordinary object
Multi-wavelength afterglow observations of the high redshift GRB 050730
McBreen, S.; Bremer, M.; Tanvir, N. +22 more
Context: .GRB 050730 is a long duration high-redshift burst (z=3.967) that was discovered by Swift. The afterglow shows variability and was well monitored over a wide wavelength range. We present comprehensive temporal and spectral analysis of the afterglow of GRB 050730 including observations covering the wavelength range from the millimeter to X…
Dust-scattered X-ray halos around gamma-ray bursts: GRB 031203 revisited and the new case of GRB 050713A
Tiengo, A.; Mereghetti, S.
Scattering by interstellar dust grains can produce time variable X-ray halos around gamma-ray bursts (GRB). In particular, an X-ray expanding ring is expected when a short pulse of X-ray radiation is scattered by a narrow layer of dust in our Galaxy. We present a new method for detecting and analyzing dust-scattering expanding rings around gamma-r…
On the horizontal branch of the galactic globular cluster NGC 2808
Zoccali, M.; Bono, G.; Cassisi, S. +3 more
We present new UV (F218W) data for stars in the central region of the Galactic globular cluster NGC 2808, collected with the WFPC2 camera on board the Hubble Space Telescope. These data together with F439W and F555W-band data and previous ground-based observations provide a multifrequency coverage of the cluster stellar population extending up to …
Probing the proper motion of the central compact object in Puppis-A with the Chandra high resolution camera
Hui, C. Y.; Becker, W.
By making use of the sub-arcsecond angular resolution of the High Resolution Camera (HRC-I) aboard the Chandra X-ray satellite we have examined the central compact object RX J0822-4300 in the supernova remnant Puppis-A for a possible proper motion. Using data which span an epoch of 1952 days we found the position of RX J0822-4300 different by 0.57…
Subaru optical observations of the two middle-aged pulsars PSR B0656+14 and Geminga
Kawai, N.; Zharikov, S. V.; Urata, Y. +6 more
Aims.We carried out a deep subarcsecond BRI imaging of the two middle-aged pulsars to establish their properties in the optical range. Methods.Astrometry and photometry methods are applied to identify the pulsars and to measure their fluxes. We also reanalyze archival ESO/NTT and HST broadband data and find that some published fluxes for Geminga w…
IGR J17252-3616: an accreting pulsar observed by INTEGRAL and XMM-Newton
Walter, R.; Stephen, J. B.; De Cesare, G. +5 more
The discovery of the X-ray source
On the CME velocity distribution
Chen, P. F.; Fang, C.; Chen, A. Q.
Context: .Coronal mass ejections (CMEs) are often categorized into flare-associated and filament-associated types, which logically is incomplete since there are many CMEs of the intermediate type.
Aims: .With this new classification, this paper aims to reexamine whether flare-associated CMEs and filament eruption-associated CMEs have distinct…
Molecular line emission in HH54: a coherent view from near to far infrared
McCoey, C.; Nisini, B.; Cabrit, S. +4 more
Aims.We present a detailed study of the infrared line emission (1-200 µm) in the Herbig-Haro object HH54. Our database comprises: high- (R ~ 9000) and low- (R ~ 600) resolution spectroscopic data in the near-infrared band (1-2.5 µm); mid-infrared spectrophotometric images (5-12 µm); and, far-IR (45-200 µm, R ~ 200) spectra …
XMM-Newton observations of the Soft Gamma Ray Repeater SGR 1627-41 in a low luminosity state
Tiengo, A.; Mereghetti, S.; Stella, L. +6 more
The sky region containing the soft gamma-ray repeater SGR 1627-41 has been observed three times with XMM-Newton in February and September 2004. SGR 1627-41 has been detected with an absorbed flux of ~9×10-14 erg cm-2 s-1 (2-10 keV). For a distance of 11 kpc, this corresponds to a luminosity of ~3× 1033 e…