Accretion onto stellar and intermediate-mass compact objects with NuSTAR

Progetto: Research project


The characteristics of NuSTAR are optimal for studies of accreting stellar- or inrmediate mass objects. Our project is aimed at exploiting these characteristics along three main lines of research. These are pilot projects which will lead to a more complete analysis of the NuSTAR archival data when they are available. The search and study of coherent and quasi-periodic signals is likely one of the most powerful tools for characterizing the different classes of cosmic X-ray sources. So far this kind of studies has been extensively applied to archival data of imaging instruments working in the "classical" 0.1-10 keV X-ray window. The NuStar archival data will allow us to extend, for the first time above 10keV with a focusing instrument, the signal search and study. It is well known that the signal properties at high energies are rather different (in many cases with very large pulsed fraction/rms) from those at lower energies, while unexpected results are always possible when new instruments are used for the first time. The aim is to carry out a timing analysis for all the detected sources in the NuStar instrument FoV (an average of 2 for each pointing) to search for new signals and/or better characterize those already known at low energies. Moreover, we plan to study variations in the Fe line parameters in X-ray binaries in correlation with other spectral and timing properties of these sources. At present there are only two LMXB in the public archive (GRS 1915+105 and 1E 1740), but they consistute already important datasets.

Layman's description

Analisi spettrale e temporale dei dati di archivio del Telescopio Spaziale NuSTAR di sorgenti X contenenti buchi neri di massa stellare o di massa intermedia.

Key findings

Data di inizio/fine effettiva12/10/1512/9/16