Wednesday Colloquium


"The intriguing Case of the Supergiant Fast X-Ray Transients: an Update"

Pietro Ubertini (Institute for Space Astrophysics and Planetology Rome, Italy)

Supergiant Fast X-ray Transients (SFXTs) are an intriguing subclass of High Mass X-ray Binaries hosting a supergiant companion. They display brief outbursts composed by bright flares lasting a few thousands seconds, during which an X-ray luminosity of 1E36-1E37 erg/s is reached. Their extreme X-ray variability, with a dynamic range of 3 to 5 orders of magnitudes from quiescence to the outburst peak, is still a matter of debate The determination of pulse and orbital periodicities are crucial to cast light on the outburst mechanism and on the evolutionary status of these X-ray binaries. The number of SFXTs where X-ray periodicities have been discovered is indeed continuously growing thanks to timing analysis of large datasets, especially from INTEGRAL/IBIS and Swift/BAT. We will review the most outcome and implication for the physical mechanisms proposed to explain the SFXTs outbursts


"Investigation of the Orientation of Galaxies in Structures"

Włodzimierz Godłowski (Opole University)

The investigation of the orientation of galaxies is a standard test of scenarios of galaxies’ formation, because different theories of galaxy formation make different predictions regarding to the angular momentum of galaxies. We analyzed the orientation of galaxy groups in the Local Supercluster (LSC). It is strongly correlated with the distribution of neighboring groups in the scale till about 20 Mpc. Moreover, we analyzed the orientation of galaxies in groups and clusters. The results show the dependence of alignments with respect to clusters richness. The implication of the results for theory of galaxy formation is discussed as well.


"Confessions of an ex-astrophysicist"

Marek Gierlinski (College of Life Sciences, University of Dundee)

I used to be an astrophysicist. Three years ago I took the plunge and got a new career in bioinformatics. In this talk I will explain what bioinformatics is about, why biologists need bioinformaticians and why (attention students!) physicists are highly sought after. I will share my personal view on modern life sciences. Biology is now a far cry from clichéd butterfly counting and in recent years has been completely transformed by cutting-edge technologies. I will focus on one particular example and describe how DNA sequencing works and show how it revolutionised our understanding of living systems.


"The luminous fate of the EROS-2 data…"

Jean-Baptiste Marquette (Institut d'Astrophysique, Paris)