The many tones of accretion - to the memory of Tomaso Belloni

Session

Multi-wavelength, Jets & Winds. Session 2.4: Spectral Modelling

9 Sept 2026, 09:30

Cefalù

124. X-ray spectral analisys in Low Mass Black Hole Binaries

Guglielmo Mastroserio (IUSS Pavia)

09/09/2026, 09:30

Talk

The rich phenomenology displayed by transient black hole X-ray binaries during outbursts offers a powerful probe of accretion physics. I will summarize our current understanding of the evolution of the X-ray spectrum across accretion states, with particular emphasis on the changing geometry of the inner accretion flow as traced by the thermal, Comptonized, and reflection components. The...

53. A gravitationally redshifted absorption line in the NICER spectrum of 4U 1820–30

rosario iaria (DiFC - UNIPA)

09/09/2026, 10:00

Talk

We report the detection of a mysterious absorption feature at approximately 3.8 keV in the Neutron star Interior Composition Explorer (NICER) spectrum of the ultracompact low-mass X-ray binary 4U 1820–30. We interpret this feature as a gravitationally redshifted iron absorption line produced in the vicinity of the neutron-star surface. This scenario is supported by the temporal proximity of...