Dual mode 5 9 12 6 bph 30

Dual mode 5 -9 -12 6 bph 30 bph TMF TMR TMF TEF TMR TER

ASTA now T 18 processing without ring Valery Dolgashev, Jim Lewandowski and Stephen Weathersby 1 June 2011 SLAC

T 18 sans ring installed. This requires twice the input power to maintain the same gradient as the ring configuration. This test will elucidate the effect of the ring (previous test) on structure performance.

88 MW @ Frequency 1. 142440 E+10, 200 ns pulsewidth. Vacuum activity mainly on the input side of the structure. 13 breakdowns at this level.

Status of T 18 in resonant ring processing Valery Dolgashev, Jim Lewandowski and Stephen Weathersby 13 April 2011 SLAC

Two rings couple the input and output power of the T 18 (18 cells) travelling wave accelerator structure. Reduces the required input power and hopefully enhances the performance of the structure. Also, the ring configuration is thought to reduce the damaging effects of breakdowns by distributing the breakdown power over time.

Pulse shape, 100 ns charging + 1500 ns flat structure input ring load structure input ring input pulse heating File: ppm_data_Mar 29_2011, trace#: 1200 with time stamp: {29, 3, 2011, 10, 29, 51, 210} Pulse. Length: 1. 54 [us] Pulse Heating: 8. 63429 [deg. C]

Pulse shape, 100 ns charging + 600 ns flat structure input ring load structure input ring input pulse heating File: ppm_data_Apr 05_2011 , trace#: 1200 with time stamp: {5, 4, 2011, 8, 39, 44, 128} Pulse. Length: 0. 64 [us] Pulse Heating: 34. 037 [deg. C]

Pulse shape, 100 ns charging + 250 ns flat structure input ring load File: ppm_data_Apr 12_2011, trace#: 1200 with time stamp: {12, 4, 2011, 8, 41, 20, 757} Max. Pulse. Length: 0. 28 [us] Pulse Heating: 24. 885 [deg. C] structure input pulse heating

Pulse shape, 100 ns charging + 100 ns flat structure input ring load File: ppm_data_Apr 20_2011 , trace#: 1200 with time stamp: {20, 4, 2011, 8, 22, 35, 155} Pulse. Length: 0. 12 [us] Pulse Heating: 18. 169 [deg. C] structure input pulse heating

T 18 in resonant ring, last ~180 hours of processing up to end of shift on April 21 st 2011 1. 5 us 600 ns flat 250 ns flat 100 ns flat 1. 5 us 600 ns flat 250 ns flat 100 ns flat

Summary of T 18 in resonant ring up to end of shift on April 12 th 2011 250 ns 400 ns 200 ns 1500 ns 600 ns 250 ns 100 ns 1500 ns 600 ns 400 ns Valery Dolgashev, Jim Lewandowski and Stephen Weathersby, 13 April 2011

Summary of T 18 in resonant ring up to end of shift on April 21 st 2011 250 ns 400 ns 200 ns 1500 ns 250 ns 200 ns 100 ns 600 ns 100 ns (2 nd experiment) 1500 ns 600 ns 400 ns 100 ns (2 nd experiment) Valery Dolgashev, Jim Lewandowski and Stephen Weathersby, 26 April 2011