Speaker
Description
Blazars are a subclass of radio-loud active galactic nuclei (AGN) with relativistic jets oriented toward the observer. They typically exhibit a flat or rising X-ray spectrum at high redshift, particularly in the hard X-ray band, which, along with their radio loudness, helps confirm their blazar nature. We present a multiwavelength study of SWIFT J0909.0+0358, a blazar candidate at redshift z=3.29. Despite being among the most luminous sources in the 157-Month Swift-BAT survey, it has not been classified as a beamed AGN in the catalog. However, its broadband spectral energy distribution (SED) indicates the presence of a powerful jet and a luminous accretion disk, making it an excellent candidate for probing the jet-disk connection in high redshift blazars. Although the source is a faint gamma-ray emitter, the inclusion of its first-ever NuSTAR data, along with Swift-XRT observation and the 157-Month Swift-BAT spectrum, allows us to better characterize its high energy SED. Our analysis reveals a flat spectrum source and constrains the cut-off energy of the hard X-rays. Using a jet and disk model in the broadband SED, we determine a higher Bulk Lorentz Factor than previous studies, suggesting a fast-moving jet with a jet power ten times the disk luminosity. Though this is model-dependent, our results are consistent with existing literature on blazars z>3. I will discuss our current progress and how future hard X-ray missions, such as a High Energy X-ray Probe-like concept, could provide deeper insights into the jet properties of high redshift blazars.
