12 GHz Stand alone Test Stand in CTFII

1. 12 GHz Stand alone Test Stand in CTFII • Conceptual design of the test area • Control system and conditioning software • Structure testing, ideas about a program

2. Stand alone Test Stand in CTFII Status: detailed mechanical design started Circular WG WG valve Mode converter load pump coupler 0.5 m Pump Tee F-Cup+Isolator ACC 0.5 m girder girder girder Concrete block All loads + Acc need water cooling 3 m

3. Control system hardware and requirements Controls Hardware PCI-Crate: CPU, Acquiris cards (4 x1 GHz) VME-Crate: CPU, timing, 2*SIS card,Buffer card, Joerger-card or equivalent, vacuum read out PLC: interlocks (modulator), phase shifter, rf switch, attenuator, temperature sensors LLRF Hardware 1 Diode chassis (8 channels) 1 IQ-chassis (8 channels) 12 GHz reference generation Timing: (rf start, rf stop, klystron start, TWT, RF switch) Phase shifter, Attenuator slow Pulse length control Vacuum Hardware Ion pumps, valves and vacuum controls F-Cup (2x)

4. Conditioning program Reads interlocks (1 Hz), rf signal (50 Hz), vacuum (1 Hz), F-Cup signals (50 Hz) Data processing to make a decision for the next pulse Display and save waveforms and history data Switches off rf, saves event data Ramps up in pulse length and amplitude after breakdown Programmable conditioning strategy, set points, time delays, moving target

5. Conditioning strategy Detect breakdown events by trigger on, missing energy, reflected power, vacuum or faraday cup signal (event type). Define thresholds and waiting times for all type of events In case of breakdown events: Switch of rf pulse, reset pulse length and power to defined values P0 and t0. Save event related data (waveforms, vacuum, …) Wait a predefined time t wait (event) (depending on event type) Switch on rf pulse, eventually reload function generator for pulse compression Ramp power in a predefined time t ramp power (power ramping time) to a predefined target power Ptarget. Ramp pulse length in a predefined time t ramp pulse length (ramping time) to a predefined pulse length tmax. Increment the target power by a predefined increment DP after a predefined time t hold power without breakdown until the predefined maximum power is reached Pmax. In case of several breakdowns (number predefined) before the required time without breakdown decrement the target power by a predefined decrement. General program features: Implement a breakdown counter and running time to determine, number of breakdowns (total and per event type) as well as breakdown rate. Provide and save history of rf pulses (peak incident power, average incident power, pulse length, peak reflection, average transmitted power, missing energy) All manual conditioning by setting above parameters as well possible (disable automatic) Possibility to trigger events for testing or saving references. Status: Marius Shekow and rf controls started working on this

6. Testing program, some remarks • Start first structure when test stand is ready, let’s plan for 1. of July 2010 • T24_CERN_kekslac_style in Germana’s structure pipeline • T18_CERN_kekslac_style as alternative if not used at SLAC • First structure will be used to ring out the test stand and its controls, but does not mean that we can’t get results as well • Plan for a second structure this year, let’s say to be ready in October TD24_CERN would be the right candidate • From 2011 on plan for 4-5 tests a year (2-3 months each) • Upgrade diagnostics and integrate ‘exotic’ structures into the program Testing scientist (‘Messknecht’): ‘Dr. ?’ Jan Kovermann