Design, Operational Experiences and Beam Results Obtained with the SNS H− Ion Source and LEBT at Berkeley Lab

“…Because the beam parameters of the HINS second phase are very similar to those for the SNS [8] it is expected that the SNS source should be able to meet all of the HINS needs.…”

Section: Long Pulse Tests Cesiated Sns Internal Antenna Sourcementioning

confidence: 99%

Ion Source Choices — An H− Source for the High Intensity Neutrino Source

Moehs¹,

Welton²,

Stöckli³

et al. 2007

“…The integrated Cs collar/outlet aperture has been conceived and developed as a result of collaborative ion source R&D work undertaken between LBNL 24 and ORNL 14 and will be described in more detail in subsequent publications. Figure 9 shows a schematic view of the assembly.…”

Section: Initial Tests Of the Integrated Cs Collar / Outlet Aperturementioning

confidence: 99%

Recent Advances in the Performance and Understanding of the SNS Ion Source

Welton¹,

Stöckli²,

Murray³

et al. 2005

Abstract. The ion source developed for the Spallation Neutron Source* (SNS) by Lawrence Berkeley National Laboratory (LBNL), is a radio frequency, multi-cusp source designed to produce ~ 40 mA of H -with a normalized rms emittance of less than 0.2 pi mm mrad. To date, the source has been utilized in the commissioning of the SNS accelerator and has already demonstrated stable, satisfactory operation at beam currents of ~30 mA with duty-factors of ~0.1% for operational periods of several weeks. Once the SNS is fully operational in 2008, a beam current duty-factor of 6% (1 ms pulse length, 60 Hz repetition rate) will be required in order to inject the accelerator. To ascertain the capability of the source to deliver beams at this high duty-factor over sustained time periods, several experimental runs have been conducted, each ~1 week in length, in which the ion source was continuously operated on a dedicated test stand. The results of these tests are reported as well as a theory of the Cs release and transport processes which were derived from these data. The theory was then employed to develop a more effective source conditioning procedure as well as an improved Cs collar design. Initial results of tests employing a Cs collar with enhanced surface ionization geometry are also discussed.

“…The main chamber consists of the multicusp vessel of the 'startup' SNS H -source which is equal to the production version [2] except for a few minor technical details. But now the entire rf antenna assembly is replaced by the cathode flange into which the primary electrons are injected, and a pulsed discharge is struck between this cathode and the multicusp chamber acting as the anode.…”

Section: Layout and Principle Of Operation For Hybrismentioning

confidence: 99%

“…The H -ion source built by LBNL for the Spallation Neutron Source (SNS) project in Oak Ridge has demonstrated excellent peak performance during the commissioning [2] and re-commissioning [3] of the SNS Front End (linac injector). A significant performance improvement overall will be required, however, when the average SNS beam-power goal is going to be raised to 3 MW.…”

Section: Introductionmentioning

confidence: 99%

A Hybrid Ion Source Concept for a Proton Driver Front End

Keller¹,

Luft²,

Regis³

et al. 2005

Self Cite

Abstract.A novel concept for creating intense beams of negative hydrogen ion beams has been devised, and first steps towards its realization have been taken. In this approach, an ECR plasma generator operating at 2.45 GHz frequency is utilized as a plasma cathode, and electrons are extracted instead of ions and injected at moderate energy into an SNStype multi-cusp H -ion source. This secondary source is then driven by chopped d. c. power, rather than rf power, but does not need filaments which are the cause for the rather short lifetime of conventional H -sources. The development of this ion source is primarily aimed at the future beam-power goal of 3 MW for the Spallation Neutron Source (SNS) [1] that will be pursued after the start of SNS operations. The first two phases of this development effort have been successfully passed: assembly of a test stand and verification of the performance of an rf-driven SNS ion-source prototype and extraction of electrons with more than 200 mA current from a 2.45-GHz ECR ion source obtained on loan from Argonne National Laboratory. An electron-extraction chamber that joins these ECR and H -sources has been fabricated, and the next goal is the demonstration of actual H -ion production by this novel, hybrid ion source. This paper describes the source principle and design in detail, reports on the current status of the development work, and gives an outlook on future lines of development.