Measurement and calculation of absolute cross sections for excitation of the 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} fine-structure transition in Fe{sup 13+}

Journal Article · Thu Feb 15 00:00:00 EST 2007 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.75.022709· OSTI ID:20982123

Hossain, S; Smith, S J; Chutjian, A ^[1]; Tayal, S S ^[2]; Raymond, J C ^[3]

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1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)
2. Department of Physics, Clark Atlanta University, Atlanta, Georgia 30314 (United States)
3. Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States)

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 eV and 6.6 eV, with a maximum cross section never exceeding about 1.2x10{sup -16} cm{sup 2}. All features are due to enhancement of the direct excitation via a multitude of narrow, closely-spaced resonances calculated by the theory, the effects of which are convoluted by the 125 meV energy resolution of the present experiment. Iron is present in practically every astrophysical object, as well as being an impurity in fusion plasmas. Present results are the highest charge state in any ion for which an absolute excitation cross section has been measured.

• OSTI ID: 20982123
• Journal Information: Physical Review. A, Vol. 75, Issue 2; Other Information: DOI: 10.1103/PhysRevA.75.022709; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
CATIONS
CENTER-OF-MASS SYSTEM
CHARGE STATES
CORRECTIONS
CROSS SECTIONS
ELECTRON CORRELATION
ELECTRONIC STRUCTURE
ENERGY RESOLUTION
EV RANGE
EXCITATION
FINE STRUCTURE
HEAVY IONS
IMPURITIES
INTERACTIONS
IRON
MULTICHARGED IONS
PLASMA
R MATRIX
RELATIVISTIC RANGE
RESONANCE