Angelo Della Riccia Fellowship

January 2009 – December 2010, Angelo Della Riccia Foundation, at Jagiellonian University, Krakow, Poland

This fellowship is for PhD holders or master holders who wish to spend a period abroad to conduct research.

Key achievements:

  • The update of La-Ta relation with 77 GRBs (Dainotti et al. 2010) has led to the discovery of a new subclass of long GRBs with plateau emission, called “canonical”, with smoothly observed X-ray light curves. These “canonical” light curves obey not only the mentioned tight physical scaling but also, for a given Ta, the more regular progenitor explosions lead to preferentially brighter afterglows. In addition, Dainotti et al. (2010) have also found a similar relation for the IC of GRBs. The remaining open questions are if this subclass could be used to explore theoretical models and to be employed as a standard candle to derive cosmological parameters.
  • The study of a sample of 69 GRBs with measured distance moduli, mu(z), in combination with a sample that obeys the La-Ta relation and the use of a Bayesian-inspired fitting method to calibrate the different GRB correlations (Cardone et al. 2009). Averaging over six correlations, Cardone at al. (2009) ended up with a new GRB HD comprising 83 objects. To avoid the need of assuming an a priori cosmological model, the so-called “circularity problem”, Cardone et al. (2009) presented a new calibration procedure based on a model-independent local regression estimate of mu(z) using the Union Type Ia SNe sample to calibrate the GRB correlations.
  • The construction of a new HD using the La– Ta correlation alone or in combination with other data Cardone et al. (2010). This analysis showed that the use of the La-Ta relation leads to constraints in the cosmological parameters in agreement with previous results in the literature. Finally, the study concluded that the best evaluation of the cosmological parameters comes from the HD made up only with the canonical GRBs.