wavel.	cross sect.	error limit

220	2.16e-18	0.26e-18
230	2.23e-18	0.25e-18
240	2.06e-18	0.23e-18
250	1.81e-18	0.22e-18
260	1.60e-18	0.18e-18
270	1.16e-18	0.14e-18
280	6.30e-19	2.50e-19
290	2.90e-19	0.40e-19