-
[show abstract]
[hide abstract]
ABSTRACT: The Low Energy Neutron Source (LENS) at Indiana University is producing neutrons by using a 7 MeV proton beam incident on a Beryllium target. The Proton Delivery System is currently being upgraded [1], [2]. A new AccSys Technology,Inc. DTL section [3] will be added to increase proton beam energy from 7 to 13 MeV. A 3 MeV RFQ and 10 MeV DTL will be powered by two 1.25 MW klystrons. The goal of this upgrade is a 13 MeV,25 mA proton beam with duty factor greater than 3%. At this power level it becomes increasingly important to make a proton beam that is uniformly distributed to prevent excessive thermal stress at the surface of the Be- target. To achieve this goal two octupole magnets are being implemented in each LENS beam transport line. In this paper we discuss the experimental results of the beam intensity redistribution as well as some features inherent in tuning of the nonlinear beamline and our operational experience.
Particle Accelerator Conference, 2007. PAC. IEEE; 07/2007
-
[show abstract]
[hide abstract]
ABSTRACT: The Indiana University Cyclotron Facility is operating a low energy neutron source which provides cold neutrons for material research and neutron physics as well as neutrons in the MeV energy range for the neutron radiation effects studies. Neutrons are being produced by a 7 MeV proton beam incident on a beryllium target. Since the first commissioning of the LENS Proton Delivery System (PDS) in December 2004 its performance has been significantly improved. The RF system of the accelerator has been upgraded by replacing 350 kW 425 MHz 12 tube amplifiers with two Litton 5773 klystron RF tubes capable of running at 425 MHz and 1.25 MW. Since the commissioning of the klystrons, a proton current of 25 mA at 7 MeV and 0.6% duty factor has been successfully delivered to the beryllium target. A future part of this upgrade will introduce a new 6 MeV DTL section to increase proton beam energy from 7 to 13 MeV. The 3 MeV RFQ and 4 MeV DTL will be powered by one klystron and the 6 MeV DTL will be powered by the second klystron. The expected output is 25 mA and 13 MeV of proton current at 0.6% duty factor. A second target station has been added to allow separate source optimization for the two primary research programs (cold neutrons and radiation effects). Other upgrades include increasing the RF duty factor to 3% through the installation of a new power supply for the klystrons. In this contribution we discuss the results of the commissioning of the new RF system, second beamline and second target station, as well as improvement in the beam parameters after these upgrades. The future plans will also be outlined.
Particle Accelerator Conference, 2007. PAC. IEEE; 07/2007
-
[show abstract]
[hide abstract]
ABSTRACT: The Indiana University Cyclotron Facility (IUCF) has constructed and placed in operation a Low Energy Neutron Source using a 10 mA, 7 MeV proton beam incident on a beryllium target. A microwave ion source used for the IUCF cyclotrons was modified to work in this application. In parallel, a 150 mA, 75 keV injector, based on the same ion source technology, is under construction. This higher current injector will be used to inject beam into a new 100 mA peak current linac that will be installed in 2006. The simulations of the 75 keV injector are reported.
Review of Scientific Instruments 03/2006; 77(3):03B501-03B501-3. · 1.37 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The Low Energy Neutron Source (LENS) at Indiana University will provide moderated neutrons in the meV energy range for materials and neutron physics research as well as MeV energy range neutrons for creating a high flux neutron test environment. Neutrons will be generated by colliding 13 MeV protons with a Be target. Since December 2004, using an existing AccSys PL-7 RFQ and DTL, we have been able to deliver a 0.5% duty factor, 10 mA, 7 MeV beam to a Be target mounted next to a 3.6K methane moderator. In 2007, an additional 7 MeV to 13 MeV DTL section will be added and klystrons will be used to power the RFQ and DTL sections. This will improve the output to about 3% duty factor with 20 mA at 13 MeV. A new 75 keV, 150 mA proton injector and 100 mA, high duty factor RFQ is being constructed to replace the original 3 MeV RFQ at a later date. The peak beam current available from the new injector and RFQ will increase to 50 mA with a duty factor of at least 5% or up to 100 mA with lower duty factor. In addition, a conceptual plan has been developed for a 13 MeV to 22 MeV DTL which will boost the maximum instantaneous flux available from the neutron source up to about 10 12 n/s/cm 2 .
-
[show abstract]
[hide abstract]
ABSTRACT: The Low Energy Neutron Source (LENS) at Indiana University is producing neutrons by using a 7 MeV proton beam incident on a Beryllium target. The Proton Delivery System is currently being upgraded [1], [2]. A new AccSys Technology, Inc. DTL section [3] will be added to increase proton beam energy from 7 to 13 MeV. A 3 MeV RFQ and 10 MeV DTL will be powered by two 1.25 MW klystrons. The goal of this upgrade is a 13 MeV, 25 mA proton beam with duty factor greater than 3%. At this power level it becomes increasingly important to make a proton beam that is uniformly distributed to prevent excessive thermal stress at the surface of the Be-target. To achieve this goal two octupole magnets are being implemented in each LENS beam transport line. In this paper we discuss the experimental results of the beam intensity redistribution as well as some features inherent in tuning of the nonlinear beamline and our operational experience.
