Search Publications
The radio-loud AGN population at z ≳ 1 in the COSMOS field. I. selection and spectral energy distributions
Chiaberge, Marco; Capetti, Alessandro; Baldi, Ranieri D. +1 more
We select a sample of radio galaxies at high redshifts (z ≳ 1) in the COSMOS field by cross-matching optical and infrared (IR) images with the FIRST radio data. The aim of this study is to explore the high-z radio-loud (RL) active galactic nuclei (AGN) population at much lower luminosities than the classical samples of distant radio sources, which…
Molecular tendrils feeding star formation in the Eye of the Medusa. The Medusa merger in high resolution 12CO 2-1 maps
Gallagher, J. S.; Petitpas, G.; Aalto, S. +5 more
Studying molecular gas properties in merging galaxies gives us important clues to the onset and evolution of interaction-triggered starbursts. NGC 4194 (the Medusa merger) is particularly interesting to study, since its FIR-to-CO luminosity ratio rivals that of ultraluminous galaxies (ULIRGs), despite its lower luminosity compared to ULIRGs, which…
The bivariate K-band-submillimetre luminosity functions of the local HRS galaxy sample
Andreani, P.; Ciesla, L.; De Looze, I. +6 more
We study the relationship between the K-band and the sub-millimetre (submm) emissions of nearby galaxies by computing the bivariate K-band-submm luminosity function (BLF) of the Herschel Reference Survey (HRS), a volume-limited sample observed in submm with Herschel/SPIRE. We derive the BLF from the K-band and submm cumulative distributions using …
The puzzling symbiotic X-ray system 4U1700+24
Masetti, N.; Del Santo, M.; Nucita, A. A. +4 more
Context. Symbiotic X-ray binaries form a subclass of low-mass X-ray binary systems consisting of a neutron star accreting material from a red giant donor star via stellar wind or Roche lobe overflow. Only a few confirmed members are currently known; 4U 1700+24 is a good candidate as it is a relatively bright X-ray object, possibly associated with …
Pre-outburst Chandra observations of the recurrent nova T Pyxidis
Balman, Ş.
Aims: I study the spectral, temporal, and spatial characteristics of the quiescent X-ray emission (not in outburst) of the recurrent nova T Pyx.
Methods: I performed the spectral analysis of the X-ray data obtained using the Chandra Observatory, Advanced CCD Imaging Spectrometer (ACIS-S3) detector. I fit the spectra with several models t…
A search for lines in the bright X-ray afterglow of GRB 120711A
Mereghetti, S.; Giuliani, A.
Gamma-ray burst (GRB) 120711A, discovered and rapidly localized by the INTEGRAL satellite, attracted particular interest due to its high γ-ray fluence and very bright X-ray afterglow and due to the detection of a prompt optical transient and long-lasting emission at GeV energies. A follow-up observation carried out with the XMM-Newton satellite ha…
Spitzer observations of a circumstellar nebula around the candidate luminous blue variable MWC 930
Umana, G.; Hora, J. L.; Trigilio, C. +4 more
Context. The source MWC 930 is a star just ~2° above the Galactic plane whose nature is not clear and has not been studied in detail so far. While a post-asymptotic giant branch classification was proposed in the past, studies of its optical spectrum and photometry pointed toward strong variability, therefore, the object was reclassified as a lumi…
HST observations of the limb polarization of Titan
Buenzli, E.; Schmid, H. M.; Bazzon, A.
Context. Titan is an excellent test case for detailed studies of the scattering polarization from thick hazy atmospheres. Accurate scattering and polarization parameters have been provided by the in situ measurements of the Cassini-Huygens landing probe. For Earth-bound observations Titan can only be observed at a backscattering situation, where t…
DN Tauri - coronal activity and accretion in a young low-mass CTTS
Schmitt, J. H. M. M.; Güdel, M.; Robrade, J. +1 more
Context. Classical T Tauri stars (CTTSs) are young, accreting low-mass stars; their X-ray emission differs from that of their main-sequence counterparts in a number of aspects.
Aims: We study the specific case of DN Tau, a young M0-type accreting CTTS, to extend the range of young CTTSs studied with high-resolution X-ray spectroscopy at lower…
A ~100 mHz QPO in the X-ray emission from IGR J17361-4441
Ferrigno, C.; Papitto, A.; Belloni, T. M. +1 more
IGR J17361-4441 was discovered by INTEGRAL undergoing its first detectable X-ray outburst in 2011 and was initially classified as an accreting X-ray binary in the globular cluster NGC 6388. A reanalysis of the outburst data collected with INTEGRAL and Swift suggested that the enhanced X-ray emission from IGR J17361-4441 could have been caused by a…