wavelength	cross sect.	uncertainty

270-279		1.34e-20	3.8e-22
280-289		1.87e-20	3.8e-22
290-299		2.41e-20	3.8e-22
300-309		2.71e-20	3.8e-22
310-319		2.60e-20	3.8e-22
320-329		2.22e-20	3.8e-22
330-339		1.41e-20	3.8e-22
340-349		8.79e-21	3.8e-22
350-359		7.26e-21	3.8e-22
360-369		1.53e-21	3.8e-22