Search results for "Ground state"
showing 10 items of 928 documents
Nuclear ground state spins of short-lived strontium isotopes
1987
Nuclear ground state spins of the odd-mass strontium isotopes between A=79 and 97 were determined by measurements of the hyperfine structure in the ionic transition 5s2S1/2−5p2P3/2. The spins of93Sr and97Sr are revised to I=5/2 and I=1/2, respectively, while assignments for the remaining isotopes are confirmed.
Nuclear spins, moments and charge radii of108?111Sn
1987
The hyperfine structure splittings (hfs) and isotope shifts (IS) in the atomic transitions 5s2 5p21S0 → 5s2 5p6s1,3P1 have been measured for the radioactive isotopes108−111Sn and all stable ones. The tin isotopes were prepared as fast atomic beams for collinear laser spectroscopy at the GSI online mass separator following a fusion reaction. Nuclear spins, magnetic dipole, electric quadrupole moments and changes in mean square charge radii have been determined. In109Sn the spinI=5/2 was measured for the nuclear ground state (T1/2=18 min) in contradiction to the literature value. The mean square charge radii show a parabolic behaviour with a maximum at N=66. This is interpreted by collective …
Hydrogen maser frequency shifts due to coherently excited Δm F =±1 transitions betweenF=1 levels of the atomic hydrogen ground state
1968
Hydrogen maser frequency shifts, caused by the multiple quantum transition nonlinearities of a resonant multiple frequency excitation of the atomic hydrogen four level ground state system have been investigated. The oscillation characteristics of hydrogen maser operation with simultaneously excited, low frequencyΔm F =±1 transitions between theF=1 states of the atomic hydrogen ground state have been analysed theoretically and explicit formulas for hydrogen maser frequency shifts and amplitude response have been derived for arbitrary maser oscillation amplitude and a small signal approximation for theΔm F =±1 “Zeeman” transitions. The comparison with experimentally observed hydrogen maser fr…
8He-6He: a comparative study of nuclear fragmentation reactions
2001
19 pages, 3 tables, 6 figures.-- PACS nrs.: 27.20.+n; 24.70.+s; 25.06.-t.-- Available online Dec 4, 2000.
Beta decay of $^{61}$Ga
1999
The β decay of 61Ga to its mirror nucleus 61Zn has been measured for the first time by using on-line mass separation and β-delayed gamma-ray spectroscopy. The observed decay strength to the ground state implies superallowed character in accordance with the systematics of the mirror decays in the sd and fp shell. The β feedings observed to four excited states in 61Zn are consistent with earlier spin-parity assignments based on in-beam experiments. The ground-state spin and parity for 61Ga were determined to be 3/2−.
Ground-state spin of 59Mn
2001
Beta decay of $^{59}$Mn has been studied at PSB-ISOLDE, CERN. The intense and pure Mn beam was produced using the Resonance Ionization Laser Ion Source (RILIS). Based on the measured $\beta$-decay rates the ground-state spin and parity are proposed to be $J^{\pi}$ = 5/2$^{-}$. This result is consistent with the systematic trend of the odd-A Mn nuclei and extends the systematics one step further towards the neutron drip line.
First observation of excited states in $^{197}$At: the onset of deformation in neutron-deficient astatine nuclei
1999
Excited states in the Z= 85 nucleus 197At have been identified for the first time using the recoil-decay-tagging (RDT) technique. The excitation energy of these states is found to be consistent with the systematics of neutron-deficient astatine nuclei and with theoretical calculations indicating that the nucleus may be deformed in its ground state.
Competing T = 0 and T = 1 structures in the N = Z nucleus $^{62}_{31}$Ga
1998
Abstract The low-lying levels in the odd-odd N = Z nucleus 62 Ga have been identified for the first time. These data reveal a cascade of stretched-E2 transitions based on a T =0, 1 + bandhead which decays directly to the T =1, 0 + ground state. The observed levels are interpreted in the context of theshell model, using as a basis, the pf 5/2 g 9/2 orbits with a 56 Ni core.
Ion storage technique for very long living states: The decay rate of the 5D 3/2 state of Ba II
1979
The metastable 5D 3/2 state of Ba+ is used to demonstrate the possibility of the ion storage technique for the measurement of extremely long lived states. The ions are confined in a r.f. quadrupole trap and excited by a strong pulsed tunable dye laser to the 6P 1/2 state which partially decays into the 5D 3/2 state. Sampling of the time development of the ground state population leads to the determination of the 5D 3/2 decay rate. Using He as a buffer gas at a pressure of about 10−6 mbar to initially store the ions, varying the gas density and extrapolating to zero pressure, we find for the lifetime $$\tau _{D_{3/2} } = 17.5 \pm 4s$$ .
Nuclear spin determination of100mY by collinear laser spectroscopy of optically pumped ions
2010
The nuclear spin of the τ1/2 = 0.94 s isomer in 100Y has been determined by collinear laser spectroscopy of optically pumped yttrium fission fragments at the IGISOL facility, JYFL. The isotopes 96, 98, 99, 100Y were produced by the proton-induced fission of natural uranium, and studied on the 4d5s 3D2 (1045 cm−1) → 4d5p 3P1 (32 124 cm−1) transition at 321.67 nm. Enhancement of the population of the metastable 3D2 level was achieved by optically pumping the ground state population via the 5s2 1S0 → 4d5p 1P1 transition at 363.31 nm while the ions were stored in a linear Paul trap. These data, when combined with previous spectroscopic results, give sufficient information for the nuclear spin o…