10th International Conference on Gravitation and Cosmology: New Horizons and Singularities in Gravity (ICGC 2023)

Revisiting the Black hole binary XTE J1859+226 to understand the disk-jet coupling.

Not scheduled

15m

IIT Guwahati

Poster Astrophysical Relativity Astrophysical Relativity

Speaker

Sreetama Das Choudhury (INDIAN INSTITUTE OF TECHNOLOGY)

Description

We revisit the black hole X-ray binary source XTE J1859+226 during its outburst phase in 1999-2000 and carry out the spectral and timing analyses using RXTE observations. Over the course of outburst, type-B QPO is observed multiple occasions and the combined spectro-temporal results reveal enhanced hard X-ray contributions as ${\rm QPO}_{\rm rms}\% \sim 1-3$, covering fraction $\sim 0.4-0.6$ and Comptonized flux ratio $\sim 0.45-0.5$. Further, type-B QPO shows a hard lag suggesting possible alteration in coronal geometry. Using continuum fitting, we estimate the spin ($a_{\rm k}$) of the source and find $a_{\rm k} \sim 0.12 – 0.38$. In addition, we attempt to connect the observed X-ray properties with the observed radio flux in the context of disk-jet coupling and estimate the jet velocity as $\sim 0.94-0.98~{\rm c}$, $c$ being the speed of light.