Lifetime determination of the Fe XIV 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} metastable level
Abstract
The lifetime of the 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} first excited energy level of Fe XIV (Al like) was measured at the Heidelberg electron beam ion trap by monitoring its optical decay to the ground state by a magnetic dipole (M1) forbidden transition at {lambda}=530.29 nm (green coronal line), a well-known line in stellar spectra. A new trapping scheme has been applied. Possible systematic effects were investigated by studying the dependence of the decay curves on various trapping conditions with high statistical significance. The result of 16.726{sub -0.010}{sup +0.020} ms shows an unexplained discrepancy in the average value of existing theoretical predictions. The inclusion of the electron anomalous magnetic moment within the theoretical calculations increases this disagreement, thus pointing at other possible origins of this discrepancy.
- Authors:
- Max-Planck Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)
- Publication Date:
- OSTI Identifier:
- 20982301
- Resource Type:
- Journal Article
- Resource Relation:
- Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032504; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS; CATIONS; DECAY; ELECTRON BEAMS; ELECTRONIC STRUCTURE; ELECTRONS; FORBIDDEN TRANSITIONS; FORECASTING; GROUND STATES; IRON; LIFETIME; MAGNETIC DIPOLES; MAGNETIC MOMENTS; METASTABLE STATES; TRAPPING; TRAPS
Citation Formats
Brenner, G., Lopez-Urrutia, J. R. Crespo, Harman, Z., Mokler, P. H., and Ullrich, J. Lifetime determination of the Fe XIV 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} metastable level. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.032504.
Brenner, G., Lopez-Urrutia, J. R. Crespo, Harman, Z., Mokler, P. H., & Ullrich, J. Lifetime determination of the Fe XIV 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} metastable level. United States. doi:10.1103/PHYSREVA.75.032504.
Brenner, G., Lopez-Urrutia, J. R. Crespo, Harman, Z., Mokler, P. H., and Ullrich, J. Thu .
"Lifetime determination of the Fe XIV 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} metastable level". United States.
doi:10.1103/PHYSREVA.75.032504.
@article{osti_20982301,
title = {Lifetime determination of the Fe XIV 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} metastable level},
author = {Brenner, G. and Lopez-Urrutia, J. R. Crespo and Harman, Z. and Mokler, P. H. and Ullrich, J.},
abstractNote = {The lifetime of the 3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} first excited energy level of Fe XIV (Al like) was measured at the Heidelberg electron beam ion trap by monitoring its optical decay to the ground state by a magnetic dipole (M1) forbidden transition at {lambda}=530.29 nm (green coronal line), a well-known line in stellar spectra. A new trapping scheme has been applied. Possible systematic effects were investigated by studying the dependence of the decay curves on various trapping conditions with high statistical significance. The result of 16.726{sub -0.010}{sup +0.020} ms shows an unexplained discrepancy in the average value of existing theoretical predictions. The inclusion of the electron anomalous magnetic moment within the theoretical calculations increases this disagreement, thus pointing at other possible origins of this discrepancy.},
doi = {10.1103/PHYSREVA.75.032504},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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Experimental cross sections are reported for the Fe{sup 13+} coronal green line transition 3s{sup 2}3p {sup 2}P{sub 1} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o}-3s{sup 2}3p {sup 2}P{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2}{sup o} at {lambda}5303 A ring (2.338 eV). The center-of-mass interaction energies are in the range 1.7 eV (below threshold) through threshold, to 6.6 eV (2.9xthreshold). Data are compared with results of a 135-level Breit-Pauli R-matrix theory. Present experiment detects a strong maximum in the excitation cross section of magnitude 15x10{sup -16} cm{sup 2} at 2.6 eV. Smaller structures are observed between 3 eVmore »
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The two metastable levels 5d {sup 2}D{sub 3} at {sub {approx}}{sub sol{approx}} at {sub 2} and 5d {sup 2}D{sub 5} at {sub {approx}}{sub sol{approx}} at {sub 2} in Ba II both show extremely long lifetimes of the order of several tens of seconds each. This has been found both by experiments and by theoretical predictions. The small transition probabilities associated with these two levels make them interesting and challenging for theoreticians as well as for experimentalists. Several calculations and measurements of these two lifetimes have been made previously but discrepancies between the results are present. This article presents values ofmore » -
Measurement of the hyperfine structure and isotope shifts of the 3s{sup 2}3p{sup 2} {sup 3}P{sub 2}{yields}3s3p{sup 3} {sup 3}D{sub 3}{sup o} transition in silicon
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