Search Publications
A general model for the identification of specific PAHs in the far-IR
Joblin, C.; Toublanc, D.; Mulas, G. +1 more
Context: .In the framework of the interstellar PAH hypothesis, far-IR skeletal bands are expected to be a fingerprint of single species in this class.
Aims: .A detailed model of the photo-physics of interstellar PAHs is required for such single-molecule identification of their far-IR features in the presently available Infrared Space Observato…
Unveiling the nature of INTEGRAL objects through optical spectroscopy. II. The nature of four unidentified sources
Palazzi, E.; Masetti, N.; Walter, R. +9 more
We present new results from our optical spectrophotometric campaign ongoing at the Astronomical Observatory of Bologna in Loiano (Italy) on hard X-ray sources detected by INTEGRAL. We have observed spectroscopically the putative optical counterparts of four more INTEGRAL sources, IGR J12391-1610, IGR J18406-0539, 2E 1853.7+1534 and IGR J19473+4452…
Oxygen abundances in metal-poor subgiants as determined from [O I], O I and OH lines
Gustafsson, B.; Asplund, M.; Nissen, P. E. +2 more
The debate on the oxygen abundances of metal-poor stars has its origin in contradictory results obtained using different abundance indicators. To achieve a better understanding of the problem we have acquired high quality spectra with the Ultraviolet and Visual Echelle Spectrograph at VLT, with a signal-to-noise of the order of 100 in the near ult…
The timing of relativistic proton acceleration in the 20 January 2005 flare
Simnett, G. M.
Understanding the energy budget in large solar flares requires a good knowledge of how and where the energetic charged particles are accelerated. If they are mainly accelerated by a Coronal Mass Ejection (CME)-driven shock, then they do not have to derive their energy from the flare region. Conversely, if the CME does not accelerate the particles,…
Outflows from young objects observed with the ISO-LWS. I. Fine structure lines [O I] 63 µm, [O I] 145 µm and [C II] 157 µm
Liseau, R.; Justtanont, K.; Tielens, A. G. G. M.
Far infrared fine structure line data from the ISO archive have been extracted for several hundred YSOs and their outflows, including molecular (CO) outflows, optical jets and Herbig-Haro (HH) objects. Given the importance of these lines to astrophysics, their excitation and transfer ought to be investigated in detail and, at this stage, the relia…
Low-resolution VLT spectroscopy of GRBs 991216, 011211 and 021211
Piro, L.; Pian, E.; Palazzi, E. +16 more
We present low-resolution VLT spectroscopy of the afterglow of the gamma-ray bursts (GRBs) 991216, 011211 and 021211. Our spectrum of GRB 991216 is the only optical spectrum for this afterglow. It shows two probable absorption systems at z=0.80 and z=1.02, where the highest redshift most likely reflects the distance to the host galaxy. A third sys…
Multi wavelength study of the gravitational lens system RXS J1131-1231. II. Lens model and source reconstruction
Surdej, J.; Riaud, P.; Sluse, D. +1 more
Aims.High angular resolution images of the complex gravitational lens system
…
IGR J16393-4643: a new heavily-obscured X-ray pulsar
Walter, R.; Bird, A. J.; Ubertini, P. +5 more
An analysis of the high-energy emission from IGR J16393-4643 (=AX J1639.0-4642) is presented using data from INTEGRAL and XMM-Newton. The source is persistent in the 20-40 keV band at an average flux of 5.1×10-11 erg cm-2 s-1, with variations in intensity by at least an order of magnitude. A pulse period of 912.0±0…
XMM-Newton observations of the σ Orionis cluster. II. Spatial and spectral analysis of the full EPIC field
Pallavicini, R.; Franciosini, E.; Sanz-Forcada, J.
We present the results of an XMM-Newton observation of the young (∼ 2{-}4 Myr) cluster around the hot star σ Orionis. In a previous paper we presented the analysis of the RGS spectrum of the central hot star; here we discuss the results of the analysis of the full EPIC field. We have detected 175 X-ray sources, 88 of which have been identified wit…
X-ray observations of RX J0822-4300 and Puppis-A
Hui, C. Y.; Becker, W.
Based on observations with the X-ray observatories Chandra and XMM-Newton we present results from a detailed spectro-imaging and timing analysis of the central compact X-ray source RX J0822-4300 in the supernova remnant Puppis-A. The superior angular resolution of Chandra allows for the first time to pinpoint the point source nature of this object…