Astrophysics (Index)About


(soft X-ray and extreme ultraviolet)
(electromagnetic radiation in the range of 0.15-124 nm)

The term XEUV (soft X-ray and extreme ultraviolet) is used for a spectrum-range covering some astronomical phenomena and attendant studies. Papers do not always specify the range they associate with the term, but clearly it is meant to cover extreme ultraviolet (EUV) and the less energetic part of the X-ray band (soft X-rays). When specified, the lower-wavelength bound is generally in the 0.1 and 0.2 nm range, but the term may sometimes be intended to cover much or all of X-rays and/or ultraviolet.

The term is useful because any defined boundary between UV and X-rays is arbitrary. Given the (somewhat-consensus) boundary of 10 nm, or any alternative, some sources would invariably emit on both sides of the boundary, some effects, such as photoevaporation, would result from EMR on both sides, and some optics techniques would be applicable to both.

Further reading:

Referenced by pages:
O-type star (O)
ultraviolet astronomy