Analysis of information sources in references of the Wikipedia article "Nuclear clock" in English language version.
A laser that emits visible light using atomic nuclei, rather than electrons, could be made from a thorium alloy. It could be a first step toward a gamma-ray laser.
The transition frequency between the I = 5/2 ground state and the I = 3/2 excited state is determined as: πTh = 1/6 (πa + 2πb + 2πc + πd) = 2020407384335(2) kHz.
Due to the extremely small transition strength in 235mU (radiative lifetime βΌ 1022 s), only 229mTh qualifies for a direct laser excitation and thus for the development of a nuclear clock.
A possibility of the amplification of the 7.6 eV Ξ³-radiation by the stimulated Ξ³-emission of the ensemble of the 229mTh isomeric nuclei in a host dielectric crystal is proved theoretically.
photons of 8.338(24) eV are measured, in agreement with recent measurements and the uncertainty is decreased by a factor of seven. The half-life of 229mTh embedded in MgF2 is determined to be 670(102) s
a narrow, laser-linewidth-limited spectral feature at 148.38219(4)stat(20)sys nm (2020407.3(5)stat(30)sys GHz) that decays with a lifetime of 568(13)stat(20)sys s. This feature is assigned to the excitation of the 229Th nuclear isomeric state, whose energy is found to be 8.355733(2)stat(10)sys eV in 229Th:LiSrAlF6.
The enhancement factor for Ξ± variation is K = β(0.82Β±0.25)Γ104.
We find that the nuclear clock's sensitivity to variations in the effective fine structure constant is enhanced by a factor of order 104.
this allows to quantify the sensitivity of Ξ± to K=5900(2300)
The nuclear resonance for the Th4+ ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum.
The transition frequency between the I = 5/2 ground state and the I = 3/2 excited state is determined as: πTh = 1/6 (πa + 2πb + 2πc + πd) = 2020407384335(2) kHz.
Due to the extremely small transition strength in 235mU (radiative lifetime βΌ 1022 s), only 229mTh qualifies for a direct laser excitation and thus for the development of a nuclear clock.
A possibility of the amplification of the 7.6 eV Ξ³-radiation by the stimulated Ξ³-emission of the ensemble of the 229mTh isomeric nuclei in a host dielectric crystal is proved theoretically.
It has been known for some time that the intrinsic state labeled by the asymptotic quantum numbers 3/2+[631] lies quite close (< 0.1 keV) to the 5/2+[633] ground state of 229Th. Using the energies of selected Ξ³ rays emitted following the Ξ± decay of 233U, we have obtained a value of 1Β±4 eV for the energy separation of these two intrinsic states.
photons of 8.338(24) eV are measured, in agreement with recent measurements and the uncertainty is decreased by a factor of seven. The half-life of 229mTh embedded in MgF2 is determined to be 670(102) s
a narrow, laser-linewidth-limited spectral feature at 148.38219(4)stat(20)sys nm (2020407.3(5)stat(30)sys GHz) that decays with a lifetime of 568(13)stat(20)sys s. This feature is assigned to the excitation of the 229Th nuclear isomeric state, whose energy is found to be 8.355733(2)stat(10)sys eV in 229Th:LiSrAlF6.
To turn the system into an actual clock, physicists will need to markedly reduce the resolution of the laser, so that it stimulates the nucleus at almost exactly the right frequency to be read off reliably, says Peik. Building such a laser 'remains a big challenge, but there are little doubts that it will be achievable in the near future', adds Kocharovskaya.
The enhancement factor for Ξ± variation is K = β(0.82Β±0.25)Γ104.
Due to the extremely small transition strength in 235mU (radiative lifetime βΌ 1022 s), only 229mTh qualifies for a direct laser excitation and thus for the development of a nuclear clock.
The nuclear resonance for the Th4+ ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum.
Due to the extremely small transition strength in 235mU (radiative lifetime βΌ 1022 s), only 229mTh qualifies for a direct laser excitation and thus for the development of a nuclear clock.
It has been known for some time that the intrinsic state labeled by the asymptotic quantum numbers 3/2+[631] lies quite close (< 0.1 keV) to the 5/2+[633] ground state of 229Th. Using the energies of selected Ξ³ rays emitted following the Ξ± decay of 233U, we have obtained a value of 1Β±4 eV for the energy separation of these two intrinsic states.
photons of 8.338(24) eV are measured, in agreement with recent measurements and the uncertainty is decreased by a factor of seven. The half-life of 229mTh embedded in MgF2 is determined to be 670(102) s
To turn the system into an actual clock, physicists will need to markedly reduce the resolution of the laser, so that it stimulates the nucleus at almost exactly the right frequency to be read off reliably, says Peik. Building such a laser 'remains a big challenge, but there are little doubts that it will be achievable in the near future', adds Kocharovskaya.
The enhancement factor for Ξ± variation is K = β(0.82Β±0.25)Γ104.
The nuclear resonance for the Th4+ ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum.
The transition frequency between the I = 5/2 ground state and the I = 3/2 excited state is determined as: πTh = 1/6 (πa + 2πb + 2πc + πd) = 2020407384335(2) kHz.
A possibility of the amplification of the 7.6 eV Ξ³-radiation by the stimulated Ξ³-emission of the ensemble of the 229mTh isomeric nuclei in a host dielectric crystal is proved theoretically.
It has been known for some time that the intrinsic state labeled by the asymptotic quantum numbers 3/2+[631] lies quite close (< 0.1 keV) to the 5/2+[633] ground state of 229Th. Using the energies of selected Ξ³ rays emitted following the Ξ± decay of 233U, we have obtained a value of 1Β±4 eV for the energy separation of these two intrinsic states.
photons of 8.338(24) eV are measured, in agreement with recent measurements and the uncertainty is decreased by a factor of seven. The half-life of 229mTh embedded in MgF2 is determined to be 670(102) s
a narrow, laser-linewidth-limited spectral feature at 148.38219(4)stat(20)sys nm (2020407.3(5)stat(30)sys GHz) that decays with a lifetime of 568(13)stat(20)sys s. This feature is assigned to the excitation of the 229Th nuclear isomeric state, whose energy is found to be 8.355733(2)stat(10)sys eV in 229Th:LiSrAlF6.
To turn the system into an actual clock, physicists will need to markedly reduce the resolution of the laser, so that it stimulates the nucleus at almost exactly the right frequency to be read off reliably, says Peik. Building such a laser 'remains a big challenge, but there are little doubts that it will be achievable in the near future', adds Kocharovskaya.
There's still much more work to be done to build a nuclear clock. And even once scientists have built them, Ye says, 'it will take years, if not decades, of work to catch up with atomic clocks.' But 'just being able to see the transition opens the door.'
We are overly excited to announce: Our teams from TU Wien and PTB Braunschweig successfully managed the laser excitation of the Th-229 Nucleus.
While this laboratory demonstration is not a fully developed nuclear clock, it contains all the core technology for one.
The nuclear resonance for the Th4+ ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum.
It has been known for some time that the intrinsic state labeled by the asymptotic quantum numbers 3/2+[631] lies quite close (< 0.1 keV) to the 5/2+[633] ground state of 229Th. Using the energies of selected Ξ³ rays emitted following the Ξ± decay of 233U, we have obtained a value of 1Β±4 eV for the energy separation of these two intrinsic states.
