POSTER

Contrˆ ole d’une instabilit´ e spatio-temporelle affectant les ´ electrons relativistes dans les centres de rayonnement synchrotron

C. Evain ¹ , C. Szwaj ¹ , E. Roussel ¹ , M. Le parquier ¹ , M.-A. Tordeux ² , M. Labat ² , F. Ribeiro ² , N. Hubert ² , J.-B. Brubach ² , P. Roy ² and S.Bielawski ¹

1 Laboratoire PhLAM/Universit´ e Lille , ² Synchrotron SOLEIL.

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P

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E n e rg y p E n e rg y p

z z z zz

(a) (b)

(c)

Naturally existing bursting solution

Coexisting regular solution (but unstable)

Induced terahertz emission

n=50 n=550 n=1050 n=1550

n=50 n=550 n=1050 n=1550

Bunch ph ase-spa ce evolution (d) Electron storage ring

Terahertz coherent synchrotron radiation

Relativistic electron bunch with micro-structures

[R´ esultats ` a paraˆıtre dans Nature Physics et en ligne sur arxiv.org/abs/1810.11805]

Dispositif exp. & r´ esultats num´ eriques

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Energy p

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(c) (d) PTHz(a.u)

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THz power Rms bunch length Feedback signal Feedback electronics

(FPGA board)

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THz detection (bolometer)

P (t) THz

RF wave used for feedback control

t V Standard RF wave destined to acceleration

Electron bunch Electron bunch

Storage ring

THz pulse

n=-2075 n=-1700 n=7300

R´ esultats exp´ erimentaux au synchrotron SOLEIL

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Bolometer signal (V) Feedback signal (kV)

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Bolometer signal (V) Feedback signal (kV)

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|TF(bolo)|2(a.u.)

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