136 research outputs found
Ground-state spin of Mn
Beta decay of 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 -decay rates the ground-state spin and parity are proposed to be = 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 direct observation of two protons in the decay of Fe with a TPC
The decay of the ground-state two-proton emitter 45Fe was studied with a
time-projection chamber and the emission of two protons was unambiguously
identified. The total decay energy and the half-life measured in this work
agree with the results from previous experiments. The present result
constitutes the first direct observation of the individual protons in the
two-proton decay of a long-lived ground-state emitter. In parallel, we
identified for the first time directly two-proton emission from 43Cr, a known
beta-delayed two-proton emitter. The technique developped in the present work
opens the way to a detailed study of the mechanism of ground-state as well as
beta-delayed two-proton radioactivity.Comment: 4 pages, 5 figure
Precision measurement of the half-life and the decay branches of 62Ga
In an experiment performed at the Accelerator Laboratory of the University of
Jyvaskyla, the beta-decay half-life of 62Ga has been studied with high
precision using the IGISOL technique. A half-life of T1/2 = 116.09(17)ms was
measured. Using beta-gamma coincidences, the gamma intensity of the 954keV
transition and an upper limit of the beta-decay feeding of the 0+_2 state have
been extracted. The present experimental results are compared to previous
measurements and their impact on our understanding of the weak interaction is
discussed.Comment: 7 pages, 7 figures, submitted to EPJ
[Formula Presented] decay of neutron-rich [Formula Presented] and [Formula Presented] isotopes
[Formula Presented] decays of on-line mass-separated neutron-rich [Formula Presented] and [Formula Presented] isotopes have been studied by using [Formula Presented] and [Formula Presented] coincidence spectroscopy. Extended decay schemes to the [Formula Presented] daughter nuclei have been constructed. The three-phonon quintuplet in [Formula Presented] is completed by including a new level at 2023.0 keV, which is tentatively assigned the spin and parity of [Formula Presented] The intruder band in [Formula Presented] is proposed up to the [Formula Presented] level at 2322.4 keV. The measured [Formula Presented]-decay half-life for the high-spin isomer of [Formula Presented] is [Formula Presented] Candidates for the three-phonon states, as well as the lowest members of the intruder band in [Formula Presented] are also presented. These data support the coexistence of quadrupole anharmonic vibration and proton particle-hole intruder excitations in [Formula Presented].</p
Q-value of the superallowed beta decay of Ga-62
Masses of the radioactive isotopes 62Ga, 62Zn and 62Cu have been measured at
the JYFLTRAP facility with a relative precision of better than 18 ppb. A Q_EC
value of (9181.07 +- 0.54) keV for the superallowed decay of 62Ga is obtained
from the measured cyclotron frequency ratios of 62Ga-62Zn, 62Ga-62Ni and
62Zn-62Ni ions. The resulting Ft-value supports the validity of the conserved
vector current hypothesis (CVC). The mass excess values measured were (-51986.5
+-1.0) keV for 62Ga, (-61167.9 +- 0.9) keV for 62Zn and (-62787.2 +- 0.9) keV
for 62Cu.Comment: 12 pages, 3 figures, 2 tables, submitted to Phys. Lett. B. v2: added
acknowledgement
A new isomer in La
Levels in La have been studied via /EC decay of on-line
mass-separated Ce using the HIGISOL technique. A new (390 40) ms isomer
is definitely attributed to La by conversion electron measurements of the 107 keV E3
isomeric transition
Artificial drainage of peatlands: hydrological and hydrochemical process and wetland restoration
Peatlands have been subject to artificial drainage for centuries. This drainage has been in response to agricultural demand, forestry, horticultural and energy properties of peat and alleviation of flood risk. However, the are several environmental problems associated with drainage of peatlands. This paper describes the nature of these problems and examines the evidence for changes in hydrological and hydrochemical processes associated with these changes. Traditional black-box water balance approaches demonstrate little about wetland dynamics and therefore the science of catchment response to peat drainage is poorly understood. It is crucial that a more process-based approach be adopted within peatland ecosystems. The environmental problems associated with peat drainage have led, in part, to a recent reversal in attitudes to peatlands and we have seen a move towards wetland restoration. However, a detailed understanding of hydrological, hydrochemical and ecological process-interactions will be fundamental if we are to adequately restore degraded peatlands, preserve those that are still intact and understand the impacts of such management actions at the catchment scale
Genome-wide meta-analysis identifies six novel loci associated with habitual coffee consumption
Coffee, a major dietary source of caffeine, is among the most widely consumed beverages in the world and has received considerable attention regarding health risks and benefits. We conducted a geno ..
Оценка качества образования на основе компетентностного подхода
В работе представлен практический опыт оценки качества образования в новом формате компетентностного подход
- …