Baseline RTML in TDR( For discussion )

S.Kuroda ( KEK )

Beam Parameters

Layout

Return Line ( ELTL/PLTL )• Following the earth’s curvature in ML tunnel

V correctors in each QV dispersion matching by v correctors at both ends

The curved orbit is introduced as ‘design’ or orbit distortion?

Diagnostics• Cavity BPM • Laser Wire for emittance measurement

New definition of RTML: BC is not included. Diagnostics and correction section upstream of BC1 is included in RTML? Polarization measurement?

Beam Physics Issues

• Stray Field– Tolerance ( K.Kubo ) • 2nT for orbit jitter of 0.2sy

– This can be corrected by fast feed-forward

• Higher for emittance growth

From what the criteria 0.2sy comes?. Criteria for emittance growth?

Stray Field ( Measurement )

N.Solyak 2011Is it OK after all?

Beam Physics Issues (2)

• Emittance Preservation ( A. Latina )

Other Beam Physics Issues in TDR• ISR

Vertical emittance growth is negligible • Beam-Ion instability ( L.Wang, et al )

– < 2mPa• Halo Formation from Scattering( S.M.Seletskiy )

– 2mPa 2e-6 of beam intensity < tolerance of 1e-5• Space-Charge Effect

– Incoherent space charge tune shift is O(0.15) in v– To be studied

Horizontal emittance growth

Arc( RTL ) 90nm (1.1 % )

Turn-around 430nm ( 5.4 % )

Back Up

K.Kubo

K.Kubo