Search Publications
On the progenitor of the type IC SN 2013dk in the antennae galaxies.
Smartt, S. J.; Benetti, S.; Maund, J. R. +7 more
We report the results of our search for the progenitor candidate of SN 2013dk, a Type Ic supernova (SN) that exploded in the Antennae galaxy system. We compare pre-explosion Hubble Space Telescope (HST) archival images with SN images obtained using adaptive optics at the ESO Very Large Telescope. We isolate the SN position to within 3σ uncertainty…
Multichromatic colour-magnitude diagrams of the globular cluster NGC 6366
Kepler, S. O.; Bonatto, C.; Campos, Fabíola +1 more
We present multichromatic isochrone fits to the colour-magnitude data of the globular cluster NGC 6366, based on Hubble Space Telescope Advanced Camera for Surveys/Wide Field Channel and Southern Astrophysical Research photometric data. We corrected the photometric data for differential reddening and calculated the mean ridge line of the colour-ma…
High-redshift Fermi blazars observed by GROND and Swift
Ghirlanda, G.; Ghisellini, G.; Tavecchio, F. +6 more
We observed five γ-ray-loud blazars at redshift greater than 2 with the X-Ray Telescope (XRT) and the UltraViolet and Optical Telescope (UVOT) on-board the Swift satellite, and the Gamma-Ray burst Optical Near-Infrared Detector (GROND) instrument. These observations were quasi-simultaneous, usually within a few hours. For four of these blazars, th…
Polarimetric studies of comet C/2009 P1 (Garradd)
Wolf, S.; Medhi, B. J.; Das, H. S. +3 more
We present the optical imaging polarimetric observations of comet C/2009 P1 (Garradd) at three different phase angles e.g. 28.2°, 28.1° and 21.6°. The observations were carried out using the Inter University Centre for Astronomy and Astrophysics (IUCAA) Faint Object Spectrograph and Camera mounted on Cassegrain focus of the 2 m telescope of IGO, I…
The planetary nebulae population in the nuclear regions of M31: the SAURON view
Bacon, Roland; Emsellem, Eric; Sarzi, Marc +5 more
The study of extragalactic planetary nebulae (PNe) in the optical regions of galaxies, where the properties of their stellar population can be best characterized, is a promising ground to better understand the late evolution of stars across different galactic environments. Following a first study of the central regions of M32 that illustrated the …
Spin and spectral variations of a peculiar high-mass X-ray binary 4U 2206+54
Wang, Wei
Spin properties and spectral variations of a high-mass X-ray binary 4U 2206+54 are studied with long-term hard X-ray monitoring observations by INTEGRAL. A long-period X-ray pulsar of Pspin ∼ 5558 s has been identified in 4U 2206+54. The spin evolution of the neutron star in 4U 2206+54 is detected with the INTEGRAL/IBIS data. From 2005 …
Chemical abundances in Orion protoplanetary discs: integral field spectroscopy and photoevaporation models of HST 10
Tsamis, Y. G.; Walsh, J. R.; Henney, W. J. +2 more
Photoevaporating protoplanetary discs (proplyds) in the vicinity of hot massive stars, such as those found in Orion, are important objects of study for the fields of star formation, early disc evolution, planetary formation and H II region astrophysics. Their element abundances are largely unknown, unlike those of the main-sequence stars or the ho…
The variable X-ray emission of PSR B0943+10
Tiengo, A.; Mereghetti, S.; Esposito, P. +1 more
The old pulsar PSR B0943+10 (P = 1.1 s, characteristic age τ = 5 Myr) is the best example of mode-switching radio pulsar. Its radio emission alternates between a highly organized state with regular drifting subpulses (B mode) and a chaotic emission pattern (Q mode). We present the results of XMM-Newton observations showing that the X-ray propertie…
The merger Seyfert galaxy Arp 220: line and continuum absorption and emission
Contini, M.
The line and continuum spectra of the merger galaxy Arp 220 are analysed with the aim of investigating the ionizing and heating sources. We refer to radio, optical, infrared and X-ray spectra. The results show that in agreement with other merger galaxies, the optical lines are emitted from gas photoionized by the active galactic nucleus (AGN) and …
Hot gas, cold gas and sub-haloes in a Lyman α blob at redshift 2.38
Scarlata, Claudia; Dopita, Michael A.; Woodgate, Bruce E. +5 more
We present integral field spectroscopy of a Lyman α blob at redshift 2.38, with a spectral resolution three times better than previous published work. As with previous observations, the blob has a chaotic velocity structure, much of which breaks up into multiple components. Our spectroscopy shows, however, that some of these multiple components ar…