Zobrazeno 1 - 10
of 70
pro vyhledávání: '"Kitsionas, S."'
Autor:
Kitsionas, S., Federrath, C., Klessen, R., Schmidt, W., Price, D., Dursi, J., Gritschneder, M., Walch, S., Piontek, R., Kim, J., Jappsen, A. -K., Ciecielag, P., Mac Low, M. -M.
Contradicting results have been reported in the literature with respect to the performance of the numerical techniques employed for the study of supersonic turbulence. We aim at characterising the performance of different particle-based and grid-base
Externí odkaz:
http://arxiv.org/abs/0810.4599
Publikováno v:
Astrophys.J.694:1161-1170,2009
The formation of the first stars out of metal-free gas appears to result in stars at least an order of magnitude more massive than in the present-day case. We here consider what controls the transition from a primordial to a modern initial mass funct
Externí odkaz:
http://arxiv.org/abs/0810.1867
Autor:
Kitsionas, S., Whitworth, A. P.
Publikováno v:
Mon.Not.Roy.Astron.Soc.378:507-524,2007
We investigate, by means of numerical simulations, the phenomenology of star formation triggered by low-velocity collisions between low-mass molecular clumps. The simulations are performed using an SPH code which satisfies the Jeans condition by invo
Externí odkaz:
http://arxiv.org/abs/astro-ph/0703177
We combine bright XMM data with the Chandra Deep Field South observations in order to explore the behavior of the intrinsic AGN absorption, as a function of redshift and luminosity.Our sample consists of 359 sources selected in the hard 2-8 keV band,
Externí odkaz:
http://arxiv.org/abs/astro-ph/0606438
Autor:
Kolokotronis, V., Georgakakis, A., Basilakos, S., Georgantopoulos, I., Plionis, M., Kitsionas, S., Gaga, T.
Publikováno v:
Mon.Not.Roy.Astron.Soc.366:163-170,2006
In this paper we serendipitously identify X-ray cluster candidates using XMM-Newton archival observations complemented by 5-band optical photometric follow-up observations (r~23 mag) as part of the X-ray Identification (XID) programme. Our sample cov
Externí odkaz:
http://arxiv.org/abs/astro-ph/0503409
Autor:
Rodriguez-Gil, P., Gaensicke, B. T., Hagen, H. -J., Marsh, T. R., Harlaftis, E. T., Kitsionas, S., Engels, D.
We report the discovery of a new, non-eclipsing SU UMa-type dwarf nova, HS 2219+1824. Photometry obtained in quiescence (V ~ 17.5) reveals a double-humped light curve from which we derive an orbital period of ~ 86.2 min. Additional photometry obtaine
Externí odkaz:
http://arxiv.org/abs/astro-ph/0409668
Publikováno v:
Astron.Astrophys.434:475,2005
(Abridged) In this paper we present photometric redshift estimates for a sample of X-ray selected sources detected in the wide field (~2 deg^2), bright [f_{X} (0.5-8 keV)~10^{-14} cgs] XMM-Newton/2dF survey. Unlike deeper X-ray samples comprising a l
Externí odkaz:
http://arxiv.org/abs/astro-ph/0406346
Autor:
Georgantopoulos, I., Georgakakis, A., Akylas, A., Stewart, G. C., Giannakis, O., Shanks, T., Kitsionas, S.
Publikováno v:
Mon.Not.Roy.Astron.Soc. 352 (2004) 91
We present an analysis of the X-ray spectral properties of 61 hard X-ray selected (2-8 keV) sources from the bright ($f_{2-8 keV}>10^{-14}$ \funits) {\it XMM-Newton}/2dF survey. This comprises of 9 {\it XMM-Newton} pointings in the North Galactic Pol
Externí odkaz:
http://arxiv.org/abs/astro-ph/0404048
Autor:
Gaensicke, B. T., Araujo-Betancor, S., Hagen, H. -J., Harlaftis, E., Kitsionas, S., Dreizler, S., Engels, D.
Publikováno v:
Astron.Astrophys. 418 (2004) 265
We report follow-up observations of a new white dwarf/red dwarf binary HS2237+8154, identified as a blue variable star from the Hamburg Quasar Survey. Ellipsoidal modulation observed in the R band as well as the Halpha radial velocity variations meas
Externí odkaz:
http://arxiv.org/abs/astro-ph/0402189
The technique of estimating redshifts using photometric rather than spectroscopic observations has recently received great attention due to its simplicity and the accuracy of the results obtained. In this work, we estimate photometric redshifts for a
Externí odkaz:
http://arxiv.org/abs/astro-ph/0309628