Previous presentation Hybrid Laminar Velocity Bunching converging on ONE UNIQUE LAYOUT? Outline Two new techniques in ONE slide 1) Hybrid LVB 2) Radio Frequency Focusing Let’s start from Marcello’s Conclusion (March 16) One unique layout Previous presentation Alberto Bacci, M. Rossetti Conti LNF 31

Previous presentation Drift @ 20 MeV ΔE =100 keV Different Bunch Charges (very good scaling) bunch length decreases linearly envelope rises linearly energy spread quasi full corrected emittance a decreasing elbow No Quadrupoles → A symmetric Beam → Very Good for BD Previous presentation C- band booster, or X-band (**) RF-focusing Modular Standing Wave cavity

Previous presentation Advantages of the two techniques Long. phase space Incorrelated Espread Correlated Espread Previous presentation No Laser Heater (High incorrelate Energy Spread): A shorter LINAC 1) RF focusing: No FODO along the LINAC → Symmetric Beam Dynamics 2) RF focusing: very short focusing channel (15um → short channel → 1-5 um) Very good performances (No Mag. Compressor): Ipeak 2÷4 kA; Low emit. <1um; Very Low E_spread 5x10^-4

Previous presentation Marcello’s Conclusions: Trying to converge in ONE layout L1 booster Mag. Compressor L2 booster Previous presentation 8.7 m Injector exit STARTING FROM L1 Booster Cristina’s solution (X-band or C-band)

2m C-band TW – ELI-like (x-band injection) (1) Testing the L1 Cristina layout (2) A common injector 10.5 m Injector exit 1.6 m drift L1 x-band Cristina’s layout considering Quads room L1 exit @ 18 m 2m C-band TW – ELI-like (x-band injection) Previous presentation (2) A common injector Modular SW ÷ 5 sectors 2 meters Modular SW ÷ 3 sectors 1.2 meters Velocity Bunchig should benefits from Standing Wave RF Focusing Anna is going to test her results by this layout

Previous presentation   Units Xband FEL-SASE 1 GeV EuPRAXIA FEL-CDR Witness bunch HLVB No.bunches 1 – (maybe 2) Bunch separation ps (maybe 83) Rep. rate Hz 10 – 100 10 Injector energy GeV 0.15 Xband Acc. Gradient MV/m > 70 Exit linac energy 1. – (1.5) 0.5 2016 2017 ? Rms Energy Spread % <1. <1  0.1 (@80 MeV) Peak current kA 2. 3 1.5 2.3 (1.1 whole) Bunch charge pC 100 30  100 Bunch length rms mm (fs) 15 (50) 3 (10) 2 (7)  8 (25) Rms norm. emittance mm < 1. <1.5 <0.6  Slice Brightness  A/m^2   4.8e16 Slice Length 0.7 0.75  0.7 fixed for binning Slice Charge 4.5 7.5 3.7  5.4 Slice Energy Spread 0.1  0.04 (@80MeV) Slice norm. emittance 1  0.28 Previous presentation Qui devo inserire tabella con valori per un fascio accelerato

(1) Testing the L1 Cristina layout and tray to avoid Quads L1 x-band booster Peak field Energies up to 500 MeV Envelops [mm] Energy spread keV/100 Emittance [mm] Space charge dominated beams do not like asymmetric dynamics

(1) Final focusing channel by 5 Permanet Quads (20 cm) sig_x, sig_y 20 cm device 45 cm @ Interaction Point Zoom box sig_z <2µm millimeters

Almost Finished activities of this analysis Comparison RF focusing for (already verified on literature): 1) HFSS 3D field map vs 2) multipolar expansion Whole Line Optimization optimization (inj+booster) by the evolutive code GIOTTO For best performances: It’s not possible uncouple injector and booster A movable Diagnostic system, in the DRIFT ZONE, to be removed after validation

Diagnostic, from last meeting Cianchi’s suggestion : Movable diagnostic system to be removed, for additional acc., after the Hybrid Laminar VB validation