wavel.	cross section	error limit

220	4.76e-18	7.20e-19
225	7.17e-18	1.08e-18
230	8.76e-18	1.31e-18
235	8.32e-18	1.25e-18
240	5.87e-18	8.80e-19
250	2.56e-18	3.90e-19
260	6.10e-19	9.00e-20
280	2.00e-19	3.00e-20