Helium (He)
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Persistent Lines of Singly Ionized Helium ( He II )
Int. Wavelength Aki Energy Configuration Term J Line Aki
(Å) (108s-1) Levels (cm-1) Ref. Ref.
300 256.3166 26.77 0.0000 1s 2S 1/2 MK00b BM00
390142.5605 3p 2P° 3/2
150 256.3177 26.77 0.0000 1s 2S 1/2 MK00b BM00
390140.8250 3p 2P° 1/2
1000 303.7804 100.27 0.0000 1s 2S 1/2 MK00b BM00
329185.1511 2p 2P° 3/2
500 303.7858 100.28 0.0000 1s 2S 1/2 MK00b BM00
329179.2940 2p 2P° 1/2
120 1640.3321 8.624 329179.2940 2p 2P° 1/2 MK00b BM00
390142.5576 3d 2D 3/2
50 1640.3447 3.593 329179.7623 2s 2S 1/2 MK00b BM00
390142.5605 3p 2P° 3/2
7 1640.3750 0.337 329179.2940 2p 2P° 1/2 MK00b BM00
390140.9646 3s 2S 1/2
25 1640.3914 3.594 329179.7623 2s 2S 1/2 MK00b BM00
390140.8250 3p 2P° 1/2
180 1640.4742 10.35 329185.1511 2p 2P° 3/2 MK00b BM00
390143.1361 3d 2D 5/2
25 1640.4897 1.725 329185.1511 2p 2P° 3/2 MK00b BM00
390142.5576 3d 2D 3/2
15 1640.5326 0.674 329185.1511 2p 2P° 3/2 MK00b BM00
390140.9646 3s 2S 1/2
4 4685.3769 0.939 390140.8250 3p 2P° 1/2 MK00b BM00
411477.8537 4d 2D 3/2
3 4685.4072 0.491 390140.9646 3s 2S 1/2 MK00b BM00
411477.8550 4p 2P° 3/2
15* 4685.7038 2.060 390142.5576 3d 2D 3/2 MK00b BM00
411478.0973 4f 2F° 5/2
15* 4685.7044 1.126 390142.5605 3p 2P° 3/2 MK00b BM00
411478.0978 4d 2D 5/2
12 4685.8041 2.207 390143.1361 3d 2D 5/2 MK00b BM00
411478.2193 4f 2F° 7/2
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