Search Publications
The formation of stellar nuclear discs in bar-induced gas inflows
Debattista, Victor P.; Erwin, Peter; Earp, Samuel W. F. +2 more
The role of gas in the mass assembly at the nuclei of galaxies is still subject to some uncertainty. Stellar nuclear discs bridge the gap between the large-scale galaxy and the central massive objects that reside there. Using a high-resolution simulation of a galaxy forming out of gas cooling and settling into a disc, we study the formation and pr…
Reproducing properties of MW dSphs as descendants of DM-free TDGs
Kroupa, Pavel; Hammer, François; Puech, Mathieu +4 more
The Milky Way (MW) dwarf spheroidal (dSph) satellites are known to be the most dark-matter (DM) dominated galaxies with estimates of dark-to-baryonic matter reaching even above 100. It comes from the assumption that dwarfs are dynamically supported by their observed velocity dispersions. However, their spatial distributions around the MW are not a…
Multiwavelength observations of the binary system PSR B1259-63/LS 2883 around the 2010-2011 periastron passage
Abdo, A. A.; Uchiyama, Y.; Chaty, S. +14 more
We report on broad multiwavelength observations of the 2010-2011 periastron passage of the γ-ray loud binary system PSR B1259-63. High-resolution interferometric radio observations establish extended radio emission trailing the position of the pulsar. Observations with the Fermi Gamma-ray Space Telescope reveal GeV γ-ray flaring activity of the sy…
Jet contributions to the broad-band spectrum of Cyg X-1 in the hard state
Stawarz, Łukasz; Zdziarski, Andrzej A.; Sikora, Marek +1 more
We apply the jet model developed in the preceding paper of Zdziarski et al. to the hard-state emission spectra of Cyg X-1. We augment the model for the analytical treatment of the particle evolution beyond the energy dissipation region, and allow for various forms of the acceleration rate. We calculate the resulting electron and emission spectra a…
Bright flares in supergiant fast X-ray transients
Sidoli, L.; Postnov, K.; Paizis, A. +1 more
At steady low-luminosity states, supergiant fast X-ray transients (SFXTs) can be at the stage of quasi-spherical settling accretion on to slowly rotating magnetized neutron stars from the OB-companion winds. At this stage, a hot quasi-static shell is formed above the magnetosphere, the plasma entry rate into magnetosphere is controlled by (ineffic…
The soft component and the iron line as signatures of the disc inner radius in Galactic black hole binaries
Done, Chris; Kolehmainen, Mari; Díaz Trigo, María
The inner radius of the accretion disc around a black hole in the low/hard state can be measured in one of two ways. First, via the extent of broadening of the iron emission line, and secondly, from the luminosity and temperature of the weak soft component seen in this state, assuming it is the disc. We use both of these methods on all the low/har…
Physical properties of fullerene-containing Galactic planetary nebulae
Otsuka, Masaaki; Peeters, E.; Bernard-Salas, J. +2 more
We searched the Spitzer Space Telescope data archive for Galactic planetary nebulae (PNe), which show the characteristic 17.4 and 18.9 µm features due to C60, also known as buckminsterfullerene. Out of 338 objects with Spitzer/Infrared Spectrograph data, we found eleven C60-containing PNe, six of which (Hen2-68, IC2501,…
The bulge-disc decomposed evolution of massive galaxies at 1 < z < 3 in CANDELS
Ferguson, H. C.; Bowler, R. A. A.; McLure, R. J. +15 more
We present the results of a new and improved study of the morphological and spectral evolution of massive galaxies over the redshift range 1 < z < 3. Our analysis is based on a bulge-disc decomposition of 396 galaxies with M* > 1011 M⊙ uncovered from the Cosmic Assembly Near-infrared Deep Extragalactic Leg…
Distribution of slow and fast rotators in the Fornax cluster
Pimbblet, Kevin A.; Graham, Alister W.; Cappellari, Michele +3 more
We present integral field spectroscopy of 10 early-type galaxies in the nearby, low-mass, Fornax cluster, from which we derive spatially resolved stellar kinematics. Based on the morphologies of their stellar velocity maps we classify 2/10 galaxies as slow rotators, with the remaining eight galaxies fast rotators. Supplementing our integral field …
The complex distribution of recently formed stars. Bimodal stellar clustering in the star-forming region NGC 346
Gouliermis, Dimitrios A.; Klessen, Ralf S.; Hony, Sacha
We present a detailed stellar clustering analysis with the application of the two-point correlation function on distinct young stellar ensembles. Our aim is to understand how stellar systems are assembled at the earliest stages of their formation. Our object of interest is the star-forming region NGC 346 in the Small Magellanic Cloud. It is a youn…