摘要:

Lifetimes for the M1 transitions from the isomeric 3.5 eV 3/2+ state to the ground state are predicted to be enhanced in the hydrogen-like229Th89+relative to the bare 229Th nucleus by several orders of magnitude. A possibility of experimental study of this phenomenon is discussed. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57382

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

With the development of a new laser ionization scheme, it became possible to ionize beryllium efficiently in the hot cavity of the ISOLDE laser ion source. The high target and ion source temperatures enable the release of short-lived beryllium isotopes. Thus all particle-stable beryllium isotopes could be extracted from a standard uraniumcarbide/graphite target. For the first time the short-lived isotopes12Beand14Becould be identified at an ISOL facility,14Bebeing among the most short-lived isotopes separated so far at ISOLDE. The release time from the UC/graphite target was studied with several beryllium isotopes. Profiting from the element selectivity of laser ionization, the strong and isotopically pure beam of12Beallowed to determine the half-life toT1/2=21.34(23)&hthinsp;msand the probability of beta-delayed neutron emission toPn=0.48−0.10+0.12&percent;.©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57386

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

TheMISTRAL*experiment is now on-line atISOLDE. Installed in May 1997,MISTRALreceived its first stable beam in October and first radioactive beam in November 1997. These first tests, with a plasma ion source, resulted in excellent isobaric separation and reasonable transmission. Further testing and development enabled first data taking in July 1998 on neutron-rich Na isotopes having half-lives as short as 31 ms. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57398

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

BEARS is an initiative to develop a radioactive ion-beam capability at Lawrence Berkeley National Laboratory. The aim is to produce isotopes at an existing medical cyclotron and to accelerate them at the88″Cyclotron. To overcome the 300-meter physical separation of these two accelerators, a carrier-gas transport system will be used. At the terminus of the capillary, the carrier gas will be separated and the isotopes will be injected into the88″Cyclotron’s Electron Cyclotron Resonance (ECR) ion source. The first radioactive beams to be developed will include 20-min11Cand 70-sec14O,produced by (p,n) and (p, &agr;) reactions on low-Z targets. A test program is currently being conducted at the88″Cyclotron to develop the parts of the BEARS system. Preliminary results of these tests lead to projections of initial11Cbeams of up to2.5×107&hthinsp;ions/secand14Obeams of3×105&hthinsp;ions/sec.©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57305

出版商:AIP    

年代:1998

数据来源: AIP

摘要:

The interest in neutron production reactions has been recently renewed because they are the basis in the development of powerful neutron sources for various purposes like nuclear energy production and incineration of nuclear waste, material structure analysis, tritium production, etc. Another interest is related to the possibility of the production of radioactive nuclei and exotic beams by neutron induced fission. One of the crucial problems in this context is to determine the most efficient way to convert the beam energy into neutrons produced afterwards. By performing the calculations with the LAHET code system [1] we try to estimate whether protons or deuterons are more favourable for neutron production. Consequently, a few direct applications of our investigations are presented and compared with experimental data. ©1998 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.57383

出版商:AIP    

年代:1998

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.57384

出版商:AIP    

年代:1998

数据来源: AIP