Speaker
Description
TeV gamma-ray binaries (TGBs) are rare, high-mass systems capable of accelerating particles to energies >10 TeV. Among them, HESS J0632+057, a candidate pulsar–Be star binary, stands out as a promising source, exhibiting phase-dependent X-ray and TeV flares. These phase-dependent flares can provide new insights into pulsar–disk interactions.
We present results from a new multi-wavelength campaign conducted in 2023-2024, combining data from Swift/XRT, NuSTAR, SALT, UVOT, and VERITAS. Our observations target the orbital phase $\phi \approx 0.3 \textrm{-} 0.4$, a critical interval during which the compact object is expected to intersect the Be star's disk. During this phase, we identify a clear transition between two distinct X-ray flux states, possibly induced by structural variability or clumpiness in the disk. This is supported by contemporaneous optical H $\alpha$ spectroscopy, which reveals changes in the disk size. The X-ray and TeV data show strong variability, including both concurrent and independent behaviors, indicative of complex, dynamic interactions between the compact object and the disk.
We discuss these findings within the context of intrabinary shock (IBS) models and pulsar–disk interaction scenarios, highlighting the role of variable shock geometry and evolving disk conditions in shaping the observed emission.
