Abstract: We investigate the radiation spectrum incident on the back end of a scale-1 halfraum,
and compare it to that measured by DANTE, at q = 37.4 deg. We use a simplified beam pointing and halfraum geometry
and test three representative XCE-albedo values and four pointings.
The radiation temperature seen by a witness plate on the
end of a
halfraum is up to 15 eV less than that seen by DANTE when the beams are pointed less than 500 mm into the halfraum. The temperatures are closer for deeper
pointings, with the witness plate TRexceeding DANTE’s in cases of low
albedo.These results are modified somewhat by the
inclusion of a LEH lip on the halfraum, and by changes to the focus offset and
beam pointing schemes.
The spectrum seen by a witness plate on the end of a halfraum differs significantly from the
spectrum seen by DANTE, even when their radiation temperatures are the same, with the witness plate spectrum being harder.