.asc files contain micro-photoluminescence spectroscopy data for one or more positions on the sample.

The values on each line of the file are separated by tab characters. All values in the file are numeric.
Each line corresponds to a particular wavelength. The first value in each line gives the wavelength in nm. Subsequent values give the number of photons detected by the CCD at that wavelength (after background subtraction).

If the filename contains "xmap(nx,sx)" and/or "ymap(ny,sy)", where nx, ny, sx and sy are arbitrary numbers, then the file contains a map over an area of the sample. The number of points in x and y are given by nx and ny respectively. The physical separation in micrometres between adjacent positions in x and y are given by sx and sy respectively.

For 1D maps (where exactly only one of xmap or ymap is present) there are nx (or ny) photon counts listed on each line, in addition to the wavelength. This corresponds to a map over a line of length (nx-1)*sx micrometres.

For 2D maps (where both xmap and ymap are present) there are nx*ny photon counts listed on each line. The first nx values correspond to y=1. The next nx values correspond to y=2. This pattern continues up to and including y=ny.

For example, a 2D map named "sample1_xmap(4,0.5)_ymap(3,0.5).asc" would contain the following data:

wavelength_1	x1y1	x2y1	x3y1	x4y1	x1y2	x2y2	x3y2	x4y2	x1y3	x2y3	x3y3	x4y3
wavelength_2	x1y1	x2y1	x3y1	x4y1	x1y2	x2y2	x3y2	x4y2	x1y3	x2y3	x3y3	x4y3
wavelength_3	x1y1	x2y1	x3y1	x4y1	x1y2	x2y2	x3y2	x4y2	x1y3	x2y3	x3y3	x4y3
wavelength_4	x1y1	x2y1	x3y1	x4y1	x1y2	x2y2	x3y2	x4y2	x1y3	x2y3	x3y3	x4y3
wavelength_5	x1y1	x2y1	x3y1	x4y1	x1y2	x2y2	x3y2	x4y2	x1y3	x2y3	x3y3	x4y3
...

where wavelength_# is a wavelength in nm and x#y# is a photon count. The map would cover an area of 1.5 by 1 micrometres.
