42 citations · 79 across the 4 of their papers we have counts for
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Growth problems of stellar black holes in early galaxies
Maria Carmela Orofino, Andrea Ferrara, Simona Gallerani
The nature of the seeds of the observed high-z super-massive black holes (SMBH) is unknown. Although different options have been proposed, involving e.g. intermediate mass direct c…
X-ray spectroscopy of the z=6.4 quasar J1148+5251
Simona Gallerani, Luca Zappacosta, Maria Carmela Orofino +9
We present the 78-ks Chandra observations of the quasar SDSS J1148+5251. The source is clearly detected in the energy range 0.3-7 keV with 42 counts (with a significance $\…
Faint progenitors of luminous quasars: why don't we see them?
Edwige Pezzulli, Rosa Valiante, Maria C. Orofino +3
Observational searches for faint active nuclei at have been extremely elusive, with a few candidates whose high- nature is still to be confirmed. Interpreting this lack…