Search results for "spectrometer"
showing 10 items of 751 documents
γ-ray spectroscopy of neutron-deficientTe110. II. High-spin smooth-terminating structures
2007
High-spin states have been populated in Te-110(52) via Ni-58(Ni-58,alpha 2p gamma) reactions at 240 and 250 MeV. The Gammasphere gamma-ray spectrometer was used in conjunction with the Microball charged-particle detector. The high-spin (I>30) collective level scheme of Te-110, up to similar to 45h, is discussed in this paper. Four new decoupled (Delta I=2) high-spin structures have been observed for the first time, together with two strongly coupled (Delta I=1) bands. These bands all show the characteristics of smooth band termination, and are discussed within the framework of the cranked Nilsson-Strutinsky approach.
Determination of the intrinsic quadrupole moment of the superdeformed band in 143Eu
1995
The intrinsic quadrupole moment, Q0, of the superdeformed band in 143Eu has been extracted from nuclear lifetimes, measured in a Doppler shift attenuation method experiment. Data were collected with the NORDBALL gamma-ray spectrometer following the reaction 110Pd (37Cl, 4n) 143Eu at a beam energy of 160 MeV. A centroid shift analysis of the data was carried out, using the Braune stopping powers to model the slowing down of the recoil nuclei in the target and backing materials. This gave a value of Q0 = 13.0 ± 1.5 eb for the band. The result is in good agreement with the theoretical prediction of Total Routhian Surface calculations, and supports the assigned single particle configuration, in…
Prolate-oblate shape coexistence in Kr-75
1998
Abstract The collective bands of 75Kr were extended up to spin 45 2 using the compound reactions 50Cr(28Si,2pn), 54Fe(24Mg,2pn) and 58Ni(20Ne,2pn)75Kr. Lifetimes were measured by RDDS with nine OSIRIS detectors in coincidence. Mixing ratios were determined by measurements of internal conversion coefficients, angular distribution and correlations. Deviations between different measurements are explained by the short lifetimes leading to angle dependent intensity losses due to Doppler shift. Spins and parities were assigned from angular distributions, excitation functions and DCO ratios measured with the OSIRIS_12 spectrometer. The band head spin of the negative parity yrast band was establish…
High-spin study of 119Xe
1998
Abstract High-spin states have been populated in 54 119 Xe via the 96 Mo( 27 Al,p3n) reaction at 133 MeV, using the Jurosphere γ-ray spectrometer to record triple γ-ray coincidences. The known level scheme has been significantly extended and several band crossings identified. In particular, the νh 11 2 yrast band has been extended to I π = ( 83 2 − ) and shows features which are consistent with those of smooth band termination at high spin. Theoretical results for 119 Xe at high spin are discussed within the framework of cranked Nilsson-Strutinsky calculations, together with results for 117 Xe.
High-spin study of neutron-deficient $^{114}$Xe
2000
Abstract High-spin states have been populated in 114 54 Xe via the 58 Ni( 58 Ni, 2p) reaction at 210 MeV, using the Jurosphere γ -ray spectrometer to record γ -ray coincidences. The known level scheme has been significantly extended and includes two positive-parity and three negative-parity structures. At the highest spins, one of the negative-parity bands becomes yrast and shows the characteristics of a smoothly terminating band. Quadrupole moments for two of the bands at high spin have been estimated through a Doppler-broadened lineshape analysis; the terminating band has a reduced quadrupole moment implying that it is not far from full termination into a noncollective oblate state. Extra…
A Recoil-Beta Tagging Study of N = Z nucleus [sup 66]As
2011
A Recoil‐Beta Tagging (RBT) experiment was recently performed at the accelerator laboratory at the University of Jyvaskyla in order to identify T = 1 excited states in the medium‐heavy N = Z = 33 nucleus 66As. The fusion‐evaporation reaction 28Si(40Ca,pn)66As was employed at a beam energy of 75 MeV. The experiment was carried out utilising the JUROGAM II γ‐ray spectrometer in conjunction with the gas‐filled recoil separator RITU and the GREAT focal plane spectrometer system. The half‐lives and ordering of the two known isomeric states in 66As have been determined. In addition, several new prompt γ‐ray transitions from excited states both bypassing and decaying to the isomeric states in 66As…
The fusion-fission process in the reaction 34S+186W near the interaction barrier
2014
International audience; The reaction 34S + 186W at Elab=160 MeV was investigated with the aim of diving into the features of thefusion-fission process. Gamma rays in coincidence with binary reaction fragments were measured using the high efficiencygamma-ray spectrometer ORGAM at the TANDEM Accelerator facility of I.P.N., Orsay, and the time-of-flight spectrometerfor fission fragments (FF) registration CORSET of the Flerov Laboratory of Nuclear Reactions (FLNR), Dubna. The couplingof the ORGAM and CORSET setups offers the unique opportunity of extracting details for characterizing the fusion-fissionprocess and gives information regarding production of neutron-rich heavy nuclei. The FF-$\gamm…
High-Accuracy Mass Determination of Unstable Rb, Sr, Cs, Ba, Fr and Ra Isotopes with a Penning Trap Mass Spectrometer
1991
The majority of masses of radioactive isotopes has been measured by determination of Q-values in nuclear reactions or in nuclear decay. For a long time the use of direct mass determination has been limited to stable isotopes or isotopes close to stability. This changed in the 70’s with magnetic spectrometers put on-line to isotope separators. The Orsay group (Audi et al., 1986) succeeded in measuring the masses in long isotope chains of alkali elements. They impressively demonstrated the possibilities embedded in direct mass determination of isotopes far from stability. The persisting demand for more precise masses of short-lived isotopes (or exotic particles) has prompted during recent yea…
A reliable screening of mycotoxins and pesticide residues in paprika using ultra-high performance liquid chromatography coupled to high resolution Or…
2016
Abstract In this study, an ultra-high performance liquid chromatography (UHPLC) coupled to a high resolution Orbitrap mass spectrometry (Orbitrap-HRMS) was demonstrated as a promising technique in high-throughput method development for the routine analysis and contamination control of mycotoxins and pesticide residues in spices. The method was applied for the analysis of fifty ground paprika samples containing blends of sweet and hot paprika harvested in Brazil and China. The efficiency and detection sensitivity of the used UHPLC-Orbitrap-HRMS technique were compared to the results obtained using a triple quadrupole tandem mass spectrometric detector (UHPLC-QqQ-MS/MS). The values of recover…
Improved sensitivity of ochratoxin A analysis in coffee using high-performance liquid chromatography with hybrid triple quadrupole-linear ion trap ma…
2016
A novel and sensitive method utilising high-performance liquid chromatography coupled to triple quadrupole-linear ion trap mass spectrometry (LC-QqQLIT-MS/MS) was developed in order to analyse the content of ochratoxin A (OTA) in coffee samples. The introduction of the triple-stage MS scanning mode (MS(3)) has been shown to increase greatly sensitivity and selectivity by eliminating the high chromatographic baseline caused by interference of complex coffee matrices. The analysis included the sample preparation procedure involving extraction of OTA using a methanol-water mixture and clean-up by immunoaffinity columns and detection using the MS(3) scanning mode of LC-QqQLIT-MS/MS. The propose…