2026-09-02 中国科学院（CAS）
AI-generated schematic illustration of the jet width profiles of SS 433. (Image by XAO)
＜関連情報＞
- https://english.cas.cn/newsroom/research-news/202609/t20260902_1189725.shtml
- https://iopscience.iop.org/article/10.3847/2041-8213/ae93b4
X線連星系におけるジェットコリメーションプロファイルの初測定：SS 433の事例 The First Measurement of Jet Collimation Profiles in an X-Ray Binary: The Case of SS 433 The Astrophysical Journal Letters Published: 2026 August 18 DOI:10.3847/2041-8213/ae93b4
Abstract
While significant progress has been achieved in active galactic nuclei, jet collimation profiles in X-ray binaries (XRBs) have not been directly measured. Here we report the first measurement of jet collimation profiles in an XRB using very long baseline interferometry data from SS 433. The approaching jet exhibits a well-constrained quasi-parabolic profile in the 1995 and 1998 data, whereas the prominent local oscillations present in the 2000 jet-width measurements preclude a robust characterization of the jet collimation profile. Nevertheless, the 2000 data suggest that the intrinsic jet opening angle decreases gradually from ∼20∘at 8 × 1014 cm to ∼3∘at 9 × 1015 cm (deprojected), providing evidence for progressive jet collimation. The width and opening angle of the receding jet are also presented, although their interpretation is limited by the free–free absorption effect. In addition, we measure the frequency-dependent core positions at four bands and derive a core-shift relation. These results establish SS 433 as the first XRB in which jet collimation, opening-angle evolution, and core-shift relation are constrained.
