RARAF Accelerator Replacement

• History of RARAF Van de Graaff

• Removal of Van de Graaff

• Placement and assembly of Singletron

• Comparison of accelerators

• Timeline for installation

RARAF Accelerator Replacement

Van de Graaff at Brookhaven National Laboratory 1949

RARAF Accelerator Replacement

Cosmotron Cosmotron injector

RARAF Accelerator ReplacementVan de Graaff at BNL before move to Nevis

RARAF Accelerator ReplacementVan de Graaff stored at Nevis and being positioned

RARAF Accelerator ReplacementNevis 200 MeV cyclotron partially disassembled and being entombed

RARAF Accelerator ReplacementVan de Graaff before removal

RARAF Accelerator ReplacementRemoving charging belt (June 13)

RARAF Accelerator Replacement

RARAF Accelerator ReplacementRemoval of acceleration tube

RARAF Accelerator Replacement

Terminal, acceleration tube and column removed

RARAF Accelerator ReplacementBaseplate with column and drive motor removed

RARAF Accelerator ReplacementMaking opening in rear wall

RARAF Accelerator ReplacementVan de Graaff tank being removed from building

(August 2)

RARAF Accelerator Replacement

RARAF Accelerator Replacement

RARAF Accelerator ReplacementRemoval of baseplate

RARAF Accelerator Replacement

RARAF Accelerator ReplacementAccelerator tank leaving Nevis

RARAF Accelerator Replacement

Interior parts of the Van de Graaff being taken away by Robert Krawchuk

RARAF Accelerator Replacement

Arrival of Singletron at RARAF (August 10)

RARAF Accelerator Replacement

RARAF Accelerator Replacement

Installation of baseplate and resonant coil tank

RARAF Accelerator ReplacementHV power supply & resonator coil

Singletron, baseplate & quadrupole

RARAF Accelerator Replacement

Interior of Singletron Terminal with shell removed

RARAF Accelerator Replacement

Parameter Van de Graaff Singletron

Terminal Voltage (MV) 0.8 - 4.2 0.2 - 5.0

Ripple (V) ~1200 200

Proton current (μA) >150 200 (100)

He current (μA) ? 125

Charging system Belt Induction

Note: Lower x-ray radiation in Singletron due to spiral acceleration tube design

Accelerator comparison

RARAF Accelerator ReplacementPrinciple of operation of a Pelletron or Van de Graaff

RARAF Accelerator Replacement

Singletron resonant coil interior Interior of tank with “Dees”

RARAF Accelerator Replacement

Electrodes & diode stacks with spark gaps

RARAF Accelerator ReplacementRF ion source

RARAF Accelerator Replacement

TASK From To

Mechanical installation (positioning, anchoring rails, etc.) 9/20 10/4

Wiring, water, ion source, function tests 10/5 10/7

Accelerator checks (open air) 10/10 10/14

INSTALLATION BREAK (1st 4 weeks over) 10/17 10/24

Tank filling and conditioning for voltage 10/25 11/2

HV test/ radiation check 11/3 11/4

Beam tests 11/7 11/11

Specification: voltage, stability, beam current 11/14 11/18

INSTALLATION BREAK (2nd 4 weeks over) 11/21 11/28

Return if necessary 11/29

Timeline for Singletron installation

RARAF Accelerator Replacement

RARAF Staff

Gerhard Randers-PehrsonAlan BigelowGuy GartyGreg RossGiusseppe Schettino

HVEE staff

Arnoud TerpstraRobert Honee