Angular distribution measurement of M band Xray from the half hohlraum

Measurement of radiation field near a implosion pellet M band Xray is a important area in ICF research.On the “SGⅡ” laser facility, M band Xray from Au plasma was measured in half hohlraum radiation from a hole about 200μm at the end. The experiment setup and typical results were given. The results indicate that angular distribution of M band Xray from the hole at the end of half hohlraum doesn't assume linear relationship with the cosine of eradiating angle, but angular distribution of O band Xray from the half hohlraum entry does.The results are very useful for the research of implosion experiment and target design.