Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “HIRFL CYCLOTRON”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2012

Performance and operation of advanced superconducting electron cyclotron resonance ion source SECRAL at 24 GHz

SECRAL (superconducting ECR ion source with advanced design in Lanzhou) ion source has been in routine operation for Heavy Ion Research Facility in Lanzhou (HIRFL) accelerator complex since May 2007. To further enhance the SECRAL performance in order to satisfy the increasing demand for intensive highly charged ion beams, 3-5 kW high power 24 GHz single frequency and 24 GHz +18 GHz double frequency with an aluminum plasma chamber were tested, and some exciting results were produced with quite a few new record highly charged ion beam intensities, such as {sup 129}Xe{sup 35+} of 64 e{mu}A, {sup 129}Xe{sup 42+} of 3 e{mu}A, {sup 209}Bi{sup 41+} of 50 e{mu}A, {sup 209}Bi{sup 50+} of 4.3 e{mu}A and {sup 209}Bi{sup 54+} of 0.2 e{mu}A. In most cases SECRAL is operated at 18 GHz to deliver highly charged heavy ion beams for the HIRFL accelerator, only for those very high charge states and very heavy ion beams such as {sup 209}Bi{sup 36+} and {sup 209}Bi{sup 41+}, SECRAL has been operated at 24 GHz. The total operation beam time provided by SECRAL up to July 2011 has exceeded 7720 hours. In this paper, the latest performance, development, and operation status of SECRAL ion source are presented. The latest results and reliable long-term operation for the HIRFL accelerator have demonstrated that SECRAL performance for production of highly charged heavy ion beams remains improving at higher RF power with optimized tuning.

43 PARTICLE ACCELERATORS↗
DOE OSTI2013

MASS MEASUREMENT OF {sup 45}Cr AND ITS IMPACT ON THE Ca-Sc CYCLE IN X-RAY BURSTS

Masses of neutron-deficient {sup 58}Ni projectile fragments have been measured at the HIRFL-CSR facility in Lanzhou, China employing the isochronous mass spectrometry technique. Masses of a series of short-lived T{sub z} = -3/2 nuclides including the {sup 45}Cr nucleus have been measured with a relative uncertainty of about 10{sup -6}-10{sup -7}. The new {sup 45}Cr mass turned out to be essential for modeling the astrophysical rp-process. In particular, we find that the formation of the predicted Ca-Sc cycle in X-ray bursts can be excluded.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2010

Nuclear physics program at HIRFL

With the commissioning of HIRFL-CSR, HIRFL can provide heavy ion beams with energy covering the range of several MeV/u to 1 GeV/u. In this talk, the experiments on nuclear physics at different energies to be carried out with different experimental setups at HIRFL will be introduced.

43 PARTICLE ACCELERATORS↗
DOE OSTI2011

The pp{yields}p{Lambda}K{sup +} and pp{yields}p{Sigma}{sup 0}K{sup +} reactions with chiral dynamics

We report on a theoretical study of the pp{yields}p{Lambda}K{sup +} and pp{yields}p{Sigma}{sup 0}K{sup +} reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state interactions of nucleon-hyperon, K-hyperon, and K-nucleon systems are also taken into account. We show that our model leads to a fair description of the experimental data on the total cross section of the pp{yields}p{Lambda}K{sup +} and pp{yields}p{Sigma}{sup 0}K{sup +} reactions. We find that the experimental observed strong suppression of {Sigma}{sup 0} production compared to {Lambda} production at the same excess energy can be explained. However, ignorance of phases between some amplitudes does not allow one to properly account for the nucleon-hyperon final state interaction for the pp{yields}p{Sigma}{sup 0}K{sup +} reaction. We also demonstrate that the invariant mass distribution and the Dalitz plot provide direct information about the {Lambda} and {Sigma}{sup 0} production mechanisms and may be tested by experiments at COSY or HIRFL-CSR.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2010

Investigation of two-proton emission from excited states of the odd-Z nucleus {sup 28}P by complete-kinematics measurements

An experiment to study exotic two-proton emission from excited levels of the odd-Z nucleus {sup 28}P was performed at the National Laboratory of Heavy Ion Research-Radioactive Ion Beam Line (HIRFL-RIBLL) facility. The projectile {sup 28}P at the energy of 46.5 MeV/u was bombarding a {sup 197}Au target to populate the excited states via Coulomb excitation. Complete-kinematics measurements were realized by the array of silicon strip detectors and the CsI+PIN telescope. Two-proton events were selected and the relativistic-kinematics reconstruction was carried out. The spectrum of relative momentum and opening angle between two protons was deduced from Monte Carlo simulations. Experimental results show that two-proton emission from {sup 28}P excited states less than 17.0 MeV is mainly two-body sequential emission or three-body simultaneous decay in phase space. The present simulations cannot distinguish these two decay modes. No obvious diproton emission was found.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗