Beam-foil lifetime measurements for some 2p3nl terms of singly-ionized fluorine

1979 ◽  
Vol 57 (7) ◽  
pp. 1046-1050 ◽  
Author(s):  
Eric H. Pinnington ◽  
Robert N. Gosselin ◽  
David J. G. Irwin ◽  
James A. O'Neill

We have used the beam-foil technique in the wavelength region between 3500 and 4500 Å to measure the lifetimes of 10 terms in F II having the configuration 2p3nl, and also to demonstrate the usefulness of the ANDC method for overcoming the effects of cascade repopulation in these measurements. Our results are in good agreement with theory and with other experimental values.

1976 ◽  
Vol 54 (10) ◽  
pp. 1014-1021 ◽  
Author(s):  
E. H. Pinnington ◽  
D. J. G. Irwin ◽  
A. E. Livingston ◽  
J. A. Kernahan

We have used the beam–foil technique to measure mean lives for 16 transitions in F I–F IV in the wavelength region 400 Å–1000 Å. Good agreement is found with the results of recent calculations, particularly those employing correlated wave functions. The f-value trends for 5 isoelectronic sequences are presented in detail (2p5 2P0–2p43s2 D and 2p5 2P0–2p43s 2P in F I; 2p4 3P–2p33s 3D0 in F II; 2p3 2D0–2s2p4 2D and 2p3 4S0–2s2p4 4P in F III). Our f value for the 955 Å multiplet in F I is also used in conjunction with some new satellite data to show that the fluorine abundance is apparently depleted in interstellar clouds by a factor of at least 3 below its solar value.


1978 ◽  
Vol 56 (5) ◽  
pp. 508-516 ◽  
Author(s):  
Eric H. Pinnington ◽  
Keith E. Donnelly ◽  
J. Anthony Kernahan ◽  
David J. G. Irwin

We have used the beam-foil technique to study the spectrum of oxygen between 270 and 490 Å. We have measured the mean lives of the 3d2F, 3d4P, 3d4D, 3d′ 2D, 3d′ 2F, 4d4P, and 4d4D terms of O II, the 3s1P0, 3s3P0, 3S5P, 3s′ 3D, 3d3P, 3d3D, 3d3F, and 3d5P terms of O III, and the 3S2S, 3P2P0, and 3s4P0 terms of O IV. All cascade components are adequately explained. Good agreement is found with previous measurements in most cases, but significant discrepancies are found with some earlier results obtained using branches above 2000 Å. Generally satisfactory agreement is also found with theoretical predictions, although disagreement is found for several members of the 2p3–2p23d array in O II f-Values are computed for 18 individual lines, and compared with other experimental and theoretical results. Finally, we discuss briefly the f-value trends along the 2p23P–2p3s3P0 (O III), 2p21D–2p3s1P0 (O III), 2s2p24P–2s2p(3P0)3s4P0 (O IV), and 2p2P0–3s2S (O IV) isoelectronic sequences.


1980 ◽  
Vol 58 (8) ◽  
pp. 1093-1098 ◽  
Author(s):  
C. Jacques ◽  
E. J. Knystautas ◽  
R. Drouin ◽  
H. G. Berry

Forty-eight new uv lines have been observed and identified in the singly and doubly excited systems of C IV, and in C V. The beam-foil technique was used to excite the spectra and to measure radiative lifetimes for 16 levels. Good agreement is found with available theoretical predictions.


Pramana ◽  
1998 ◽  
Vol 50 (3) ◽  
pp. 231-237
Author(s):  
B N Raja Sekhar ◽  
S Padmanabhan ◽  
Aparna Shastri ◽  
P Meenakshi Raja Rao ◽  
M B Kurup ◽  
...  

1988 ◽  
Vol 66 (5) ◽  
pp. 402-404 ◽  
Author(s):  
W. Ansbacher ◽  
E. H. Pinnington ◽  
J. A. Kernahan

Beam-foil intensity decay curves for transitions in the wavelength range from 900 to 2200 Å are used to derive the lifetimes of the 6s6p1P1 and 3P1 6s6d1D2, 6s7s1S0, and 6p21D2 levels of Pb III, and the 6p2P1/2 and 2P3/2, 6d2D3/2 and 2D5/2, 7s2S1/2, and 5d96s22D3/2 levels of Pb IV, arbitrarily normalized decay curve (ANDC) analyses being used for the 6s6p and 6p levels. In the case of the two 6s6p levels studied in Pb III, good agreement is found with a recent calculation in which a polarization model accounts for valence–core correlation. However, the agreement between the lifetimes observed for the 6p levels in Pb IV and a similar, earlier calculation is only fair.


2005 ◽  
Vol 83 (11) ◽  
pp. 1127-1139 ◽  
Author(s):  
K W Kukla ◽  
A E Livingston ◽  
C M Vogel Vogt ◽  
H G Berry ◽  
R W Dunford ◽  
...  

We have studied the spectrum of highly ionized krypton in the extreme-ultraviolet wavelength region (50–300 Å), using beam-foil excitation of fast krypton ions at the Argonne ATLAS accelerator facility. We report measurements of transition wavelengths and excited-state lifetimes for n = 2 states in the lithiumlike, berylliumlike, and boronlike ions, Kr31+,32+,33+. Excited state lifetimes ranging from 10 ps to 3 ns were measured by acquiring time-of-flight-delayed spectra with a position-sensitive multichannel detector.PACS Nos.: 32.70.Cs, 32.30.Jc, 34.50.Fa


1985 ◽  
Vol 63 (10) ◽  
pp. 1330-1333 ◽  
Author(s):  
W. Ansbacher ◽  
E. H. Pinnington ◽  
J. L. Bahr ◽  
J. A. Kernahan

A brief description is given of the modifications to a 2-MV Van de Graaff accelerator that are required to incorporate a field-emission ion source. The source is used to obtain a 1-μA beam of Ga+ ions. Lifetime measurements using the beam-foil technique are reported for the 4s5s1S, 4s4p1P, 4s4d1D, 4s5d1D, 4p21D, 4s5s3S, 4p23p, and 4s4d3D terms of Ga II and for the 5s2S, 4p2P, 4d2D, and 5f2F terms of Ga III. A detailed discussion is given of the cascading problem in the case of the Ga II resonance transition at 1414 Å.


1977 ◽  
Vol 55 (15) ◽  
pp. 1310-1315 ◽  
Author(s):  
J. A. Kernahan ◽  
K. E. Donnelly ◽  
E. H. Pinnington

We have measured radiative mean lives from 24 transitions in Ne II–Ne VI in the wavelength range 209–602 Å using the beam-foil technique. We present the first experimental mean lives for nine levels, and our results are compared where possible with theoretical calculations and with other experimental values.


1986 ◽  
Vol 64 (10) ◽  
pp. 1365-1368 ◽  
Author(s):  
W. Ansbacher ◽  
E. H. Pinnington ◽  
J. A. Kernahan ◽  
R. N. Gosselin

Lifetime measurements obtained by the beam-foil method are given for 13 levels in In II and 12 levels in In III. Particular attention has been paid to cascade correction with the application of a new arbitrarily normalized decay curves (ANDC) program. The results are compared with theory, and good agreement is found with recent multiconfiguration relativistic Hartree–Fock (MCRHF) calculations for the In II resonance transition. The results for 2P and 2D levels in In III and 1D levels in In II indicate a need for further calculations.


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