Hamburg 2013.05.28

European Linear Collider Workshop ECFA LC2013

Krzysztof Krzysik

XFEL AMTF Cavity and Module RF Measurement

Procedures

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

RF Team has to test …

840 Cavities

103 Modules

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Test of Cavity

•spectrum measurement (warm)

Incoming inspection

•spectrum measurement (warm)

•HOM couplers tuning

•cables connection (insert) + TDR check

Preparation

•cables connection (test-stand) and calibration

•spectrum measurement (cold)

•power rising (qe curves)

Vertical test

•spectrum measurement (warm)

Outgoing inspection

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Spectrum measurement (warm)

Array of points (freq, S21)input-pickup

Frequencies of fundamental modes “Field flatness”

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

HOM couplers tuning

Setting up minimum of the rejection filter: hom1, hom2 Array of points (freq, S21)pickup-hom1 / input-hom2

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cables connection (insert) and TDR check

Cables connection in insert Circuit check (discontinuity, short) with Time Domain

Reflectometry

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Vertical test-stand - schematic

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cable connection (test-stand) and calibration

Cable connection in test-stand Calibration – power correction measurement

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Spectrum measurement (cold)

Frequencies of fundamental modes Lock on 9/9π mode Phase (Pfor, Ptrans)

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Power rising (qe curves)

Max Eacc (limitation)

Q0-factor vs. Eacc

Radiation vs. Eacc

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Test of Module

•spectrum measurement (warm)Incoming

inspection

•warm coupler conditioning

•coupler conditioning during cool-down

Preparation•cold cables calibration

•cavities tuning with VNA

•Qext adjustment

•HOM spectra measurements

Test @ 2K(low power)

•cavities fine tuning

•cavities calibration

•cavities performance test

•heat loads measurements

Test @ 2K(high power)

•spectrum measurement (warm)Outgoing

inspection

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Warm coupler conditioning /Coupler conditioning during cool-down

Removal of impurities from the couplers Sequence of pulses (power, length)out of resonance

Warm: room temperature, cool-down: up to 100K

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cold cables calibration

Cold cables calibration – reflection mode (S11)

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cavities tuning with VNA / Qext adjustment

Cavities tuning near resonance: with VNA and tuning application (rough frequency tuning)

Qext adjustment: with VNA (manually) or with klystron (motors on couplers)

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

HOM spectra measurement

Frequencies and Qhom1 / hom2 for TM011, TE111 and TM110 peaks.

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cavities fine tuning

Cavities fine tuning – with LLRF Monitoring system and Tuning Application

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Cavities calibration

Cavities calibration (before flat-top): Kt

Qload, Qtrans, Qhom1, Qhom2

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Max Eacc (limitation)

Eacc @ radiation = 10-2 mGy/min (operating gradient)

Cavities performance test (flat-top)

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Heat loads measurement

Heat loads ~ Q0-factor vs. Eacc

XFEL AMTF Cavity and Module RF Measurement Procedures

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2013.05.28 HamburgKrzysztof Krzysik

Thank You for Your attention