Speaker
Description
We present a high-resolution spectroscopic study of the ultracompact neutron-star LMXB 4U 1916–053 (Porb ≈ 50 min), a prototypical dipping system in which recurrent intensity drops are produced by variable absorption in disk-associated plasma. Using new XRISM/Resolve observations together with simultaneous XMM-Newton data, we investigate the structure, ionization state, and kinematics of the accretion-disk atmosphere and search for signatures of ionized outflows. We use phase- and time-resolved spectroscopy to follow changes in the absorber with orbital phase, on longer timescales that may be related to superorbital variability from disk precession, and during episodes of enhanced irradiation associated with thermonuclear (Type-I) bursts. We focus on higher-energy diagnostics that probe the ionization and dynamics of the inner disk, and use them to constrain the geometry, composition, and variability of the plasma, and to assess possible wind-driving mechanisms. By combining the spectral resolution of XRISM with the complementary bandpass of XMM-Newton, we aim to clarify the connection between accretion, winds, and nuclear burning in compact X-ray binaries.
| Talk category | NOVA Network 3 |
|---|
