Comparison of DC and RF conditioning

Jorge Giner-NavarroA.Degiovanni, N.Shipman, W.Wuensch

and on behalf of the Breakdown studies and DC Spark team09/04/2014

CLIC RF Structure Development Meeting

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Conditioning history of TD26R05CC at XBOX1 (CERN)

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

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History plot of TD24R05 at NEXTEF (KEK)

T. Higo CLIC Workshop 2014J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

1060 BDs 591 BDs

Conditioning BDR measurements

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History plot of HRR Fixed-Gap System at DC Spark lab

(window= 50M Pulses)

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

Voltage pulse lengthtp=12 µs

Gap = 15µm

509/04/2014

Normalized Surface Electric Field

𝐸𝑠

𝑡𝑝−1 /6 BDR1/30

𝐸𝑠∝𝐸0∝𝑡𝑝− 1/6BDR1/30

Gradient scaling law

J. Giner-Navarro - CLIC RF Structure Development meeting

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Normalized Surface Electric Field𝐸𝑠

𝑡𝑝−1 /6 BDR1/30

Same conditioning level at different number of BD

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

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Normalized BreakDown Rate

BDR

E s❑30 𝑡𝑝

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BDR∝ E s❑30 𝑡𝑝

5BDR scaling law

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

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Thank you for your attention !

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

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EXTRA SLIDES

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

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Normalized BreakDown Rate per unit Area

BDR / AE s

❑30𝑡𝑝5

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

Area with 95% of the max Electric field:

TD26R05CC 646 mm2

TD24R05 612 mm2

FFG electrodes 5655 mm2

(approx estimation)

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Evolution of BDR vs Surf E field

J. Giner-Navarro - CLIC RF Structure Development meeting

09/04/2014

• For the same Es , BDR decreases• We reach same level of BDR with

higher Es

HRR Fixed Gap System