US5376246A
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Efficient mass-selective three-photon ionization of zirconium atoms
Assignee: UNITED STATES OF AMERICAN AS REPRESENTED BY DEPARTMENT OF ENERGY
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Filing: 1992-12-02
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Granted: 1994-12-27
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Expires: 2012-12-02
Abstract
Abstract In an AVLIS process, 91 Zr is selectively removed from natural zirconium by a three-step photoionization wherein Zr atoms are irradiated by a laser beam having a wavelength λ 1 , selectively raising 91 Zr atoms to an odd-parity E 1 energy level in the range of 16000-19000 cm -1 , are irradiated by a laser beam having a wavelength λ 2 to raise the atoms from an E l level to an even-parity E 2 energy level in the range of 35000-37000 cm -1 and are irradiated by a laser beam having a wavelength λ 3 to cause a resonant transition of atoms from an E 2 level to an autoionizing level above 53506 cm -1 . λ 3 wavelengths of 5607, 6511 or 5756 Å will excite a zirconium atom from an E 2 energy state of 36344 cm -1 to an autoionizing level; a λ 3 wavelength of 5666 Å will cause an autoionizing transition from an E 2 level of 36068 cm -1 ; and a λ 3 wavelength of 5662 Å will cause an ionizing resonance of an atom at an E 2 level of 35904 cm -1 .
Inventors
- 👤 Ralph H. Page
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:44
CPC Classifications
B; B01; B01D; B01D59/00; B01D59/34
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
153 words
A method of selectively ionizing and extracting zirconium atoms of isotope 91 ( 91 Zr) from a stream of zirconium atoms that includes 91 Zr and other zirconium isotopes, comprising the steps of: a) irradiating the stream of zirconium atoms with a first laser beam having a wavelength λ 1 that causes a resonant transition of 91 Zr atoms from a stable state energy level to an odd-parity E 1 energy level; b) irradiating the stream of zirconium atoms with a second laser beam having a wavelength λ 2 that causes a resonant transition of 91 Zr atoms from an E 1 energy level to an even-parity E 2 energy level; and c) irradiating the stream of zirconium atoms with a third laser beam having a wavelength λ 3 that causes a resonant transition of 91 Zr atoms from an E 2 energy level to an autoionizing level above 53506 cm -1 .
Claim 2
Independent Claim
153 words
A method of selectively ionizing and extracting zirconium atoms of isotope 91 ( 91 Zr) from a stream of zirconium atoms that includes 91 Zr and other zirconium isotopes, comprising the steps of: a) irradiating the stream of zirconium atoms with a first laser beam having a wavelength λ 1 that causes a resonant transition of 91 Zr atoms from a stable state energy level to an odd-parity E 1 energy level; b) irradiating the stream of zirconium atoms with a second laser beam having a wavelength λ 2 that causes a resonant transition of 91 Zr atoms from an E 1 energy level to an even-parity E 2 energy level; and c) irradiating the stream of zirconium atoms with a third laser beam having a wavelength λ 3 that causes a resonant transition of 91 Zr atoms from an E 2 energy level to an autoionizing level above 53506 cm -1 .
Claim 3
Dependent Claim
24 words
The method as set forth in claim 1, wherein the energy level E 2 in steps (b) and (c) is 36344 cm -1 .
Claim 4
Dependent Claim
19 words
The method as set forth in claim 2, wherein the wavelength λ 3 in step (c) is 5607 Å.
Claim 5
Dependent Claim
19 words
The method as set forth in claim 2, wherein the wavelength λ 3 in step (c) is 5611 Å.
Claim 6
Dependent Claim
19 words
The method as set forth in claim 2, wherein the wavelength λ 3 in step (c) is 5756 Å.
Claim 7
Dependent Claim
35 words
The method as set forth in claim 1, wherein the energy level E 2 in steps (b) and (c) is 36068 cm -1 , and the wavelength λ 3 in step (c) is 5666 Å.
Claim 8
Dependent Claim
35 words
The method as set forth in claim 1, wherein the energy level E 2 in steps (b) and (c) is 35904 cm -1 , and the wavelength λ 3 in step (c) is 5662 A.
Claim 9
Dependent Claim
45 words
The method as set forth in claim 7, wherein the energy level E 1 in steps (a) and (b) is 18244 cm -1 , and the wavelength λ 2 in step (b) is the same as that of the wavelength λ 3 in step (c).
Claim 10
Dependent Claim
52 words
The method as set forth in claim 1, wherein said steps of irradiating with laser beams having wavelengths λ 1 , λ 2 , λ 3 , include using three independently tunable lasers to provide excitation of 91 Zr atoms at said wavelengths λ 1 , λ 2 , λ 3 .
References Cited (Backward Citations)
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