DAFNE UPGRADE DAFNE Upgrade Team Scientific CommitteeMay 14

DAFNE UPGRADE DAFNE Upgrade Team Scientific Committee-May 14 -15, 2007 LNF - Italy

Crabbed Waist in 3 Steps 1. Large Piwinski’s angle F = tg(q)sz/sx 2. Vertical beta comparable with overlap area by sx/q 3. Crabbed waist transformation y = xy’/(2 q) P. Raimondi, November 2005

Crabbed Waist Advantages a) Geometric luminosity gain 1. Large Piwinski’s angle 2. b) Very low horizontal tune shift F = tg(q)sz/sx 3. 2. Vertical beta comparable 4. with overlap area by s x/ q 3. Crabbed waist transformation y = xy’/(2 q) a) Geometric luminosity gain b) Lower vertical tune shift c) Vertical tune shift decreases with oscillation amplitude d) Suppression of vertical synchro-betatron resonances a) Geometric luminosity gain b) Suppression of X-Y betatron and synchro-betatron resonances

Parameters used in simulations Horizontal beta @ IP Vertical beta @ IP 0. 2 m (1. 7 m) 0. 65 cm (1. 7 cm) Horizontal tune 5. 057 Vertical tune 5. 097 Horizontal emittance 0. 2 mm. mrad (0. 3) Coupling 0. 5% Bunch length 20 mm Total beam current 2 A Number of bunches 110 Total crossing angle 50 mrad (25 mrad) Horizontal beam-beam tune shift 0. 011 Vertical beam-beam tune shift 0. 080 L => 2. 2 x 1033 cm-2 s-1

SIDDHARTA IR Luminosity Scan Crab On --> 0. 6/q Crab Off 0. 2 0. 18 0. 16 0. 14 0. 12 0. 1 0. 08 0. 06 0. 08 0. 12 0. 14 0. 16 0. 18 0. 2 Lmax = 2. 97 x 1033 cm-2 s-1 Lmax = 1. 74 x 1033 cm-2 s-1 Lmin = 2. 52 x 1032 cm-2 s-1 Lmin = 2. 78 x 1031 cm-2 s-1

Dynamic Aperture tune scan Luminosity tune scan D. Shatilov, M. Zobov

Off Energy Dynamic Aperture D. Shatilov, M. Zobov

Beam Lifetime Comparison between Siddharta and FINUDA lattices for the same beam parameters RF 1% No scrapers Touschek lifetime is evaluated taking into account vacuum chamber aperture but no dynamic aperture S. Guiducci

Trajectories of Touschek particles generated all along the ring that get lost at the IR Simulation shows how collimators strongly reduce background at the IR SCHPS 101 SCHPL 201 SCHPL 110 IP SCHPS 201 SCHPL 101 Set of scrapers minimizing IR background SCHPL 101 = 8. 5 sx = 11 mm (moved at s = -8. 2 m from IP) SCHPL 110 = 18 sx = 18 mm SCHPS 201 = 21 sx = 21 mm (moved at s = -44 m from IP) M. Boscolo

Beam lifetime as a function of the scraper’s aperture S. Guiducci

New Crossing Regions Layout • remove splitters (on both interaction regions) • new vacuum chambers for IP regions • adjust dipole fields and position (Blong lower, Bshort higher - splitters power supplies) • new permanent magnets in the IP 1 region • readjust all the other elements (quads, sexts etc) • new components construction (kickers, bellows, diagnostics, etc) • new vacuum system for IP regions

Crossing Region layout cont. New beam line IP QF 1 s QD 0 s

Large Crossing Angle and Crabbed Waist Scheme

Large Crossing Angle and Crabbed Waist Scheme

S. Tomassini et all.

• Aluminum made (very cheap) • Thin window thickness= 0. 3 mm • Mechanical and Vacuum test done • Construction in progress 150 W F. Marcellini and D. Alesini permanent Sm. Co quads mode 1 mode 2 mode 3 mode 4

new compensator position, will not installed in SIDDHARTA setup new pumping system needed to replace previous slitter pumping system power new bellows

New Shielded bellows Axial working stroke = ± 5 mm Radial offset = ± 3 mm HFSS simulation • Beam excited fields in the bellows structure • No significant fields in the volume beyond the shield F. Marcellini, G. Sensolini

tilted and separately powered dipoles bellows crab sextupoles compensator

“half moon” chamber complete beam separation shape to fit inside existing quads

IP 2 Y is completely symmetric to IP 1 except for crab waist sextupoles and compensator

New Injection Kickers New injection kickers with 5. 4 ns pulse length have been designed to reduce the perturbation on the stored beam during injection VT VT 3 bunches 50 bunches present pulse length ~150 ns (old kickers) t FWHM pulse length ~5. 4 ns t Expected benefits: • higher maximum stored currents • Improved stability of colliding beams during injection • less background allowing acquisition on during injection F. Marcellini, D. Alesini, G. Sensolini , S. Pella

Fast Kickers • Kicker prototype preliminary test performed • Kicker final design completed • Pulse generator prototype under test (80 hours tested @3 Hz done) • 50 KV final feedthrough will be tested next week • Delivery of the first Kicker by the end of May • Engineering of pulse system supply and controls implementation already order to the manufacture • Improved pulser version by the end of May • Remote controls implementation for August F. Marcellini, D. Alesini, G. Sensolini, S. Pella

VACUUM CHAMBER modifications • 80 m long of storage ring reshaped (40% of DAFNE storage ring) • 70 m long of new vacuum chambers designed and under manufacturing • Designed new shielded bellows • Vacuum plant upgraded; quotation for new pumping units in progress • New fast kickers manufacturing in progress QTÀ Esistenti DA COSTRUIRE NUMERO PARTE DESCRIZIONE 6 4 2 SR 02 -100 Disegni OK / Richieste offerte 8 1 7 SR 02 -092 Disegni OK / Richieste offerte 2 2 0 SR 02 -093 Riusata 4 4 0 SR 02 -123 Riusata 8 8 0 RF-All-Metal Gate Valve 4 0 4 SR 02 -009 -000 4 2 2 sr 02 -133 Disegni OK / Richieste offerte 2 2 0 SR 02 -131 Riusata 4 0 4 SR 02 -013 -000 4 SR 02 -006 -000 2 SR 02 -000 16 1 0 1 RF-All-Metal Gate Valve NOTE Riusate CV-soffietto KEK Like or FRASCATI Like? Camera x_C Disegni 90% / richieste offerte

SIDDHARTA Setup SIDDHARTA Kaon monitor focusing quads bhabha monitor lead shield gamma monitor

Machine luminosity monitors and IP diagnostics tool • e+ e- g (8. 5 e-26 cm-2 s-1@E>100 Me. V, e+ e- Z g (<10% background) 95% 1. 7 mrad) • e+ e- g g (6. 6 e-29 cm-2 s-1@E>100 Me. V, 15% 1. 7 mrad) now limited by accidentals (@10^32 and chamber vertical acceptance) • e+ e- Bhabha scattering - more clean process 312. 5 Hz @ 18 o<q<27 o @ 1033 cm-2 s-1 F. Bossi, P. Branchini, B. Buonumo, G. Mazzitelli, F. Murtas, P. Valente DAFNE-KLOE collaboration with the support of SSCR

Luminosity monitor for SIDDAHRTA run TILE CALORIMETER g MONITOR Pb. WO 4 crystal GEM RING

Tile Bhabha calorimeter (lumi) • 4 calorimeter composed by 5 30 o sectors • 7 lead sheet 5 mm - 3 final lead sheet 10 mm • 12 30 o scintillating tile for sector • 3 WLS each tile • 1 PM for any sector (20 PM) • 12. 5 X 0 15% resolution @ 510 Me. V • First tail Russian sample arrived • WLS installed and light emission tested • BTF test planed for October • PM, Electronics and DAQ by KLOE

A 3 GEM Monitor for DAFNE rectangular GEM prototype under test @ DAFNE 10 cm 2. 4 cm Annular gem foil design for bhabha detector @ DAFNE 64 pads 10 cm The read out has been realized using 8 chip ASDQ (8 channel each) Test at BTF 99% efficiency for electron (signal in bhabha measure) ~ 1% efficiency for photons (background in bhabha measure) 32 + 32 channels

3 GEM monitor test on DAFNE On April 2007 the 3 gem chamber has been put at zero degree on DAFNE for photon detection coming from the FINUDA interaction region ee+ 3 GEM lead beamstrahlung number of photon vs time and FINUDA luminosity photon spot-size g

Order Status Progress … Layout desig. Estimate (Keuro) request order IP QUADS OK 380 OK OK IP 1 chambers OK 47 OK OK Complete of vacuum test (CECOM) chambers OK 20. 8 OK OK Complete of vacuum test (RMP) chambers OK 30 OK IP 2 chambers OK 30 In prog. KCK chamber OK 18 In prog. Vacuum pumps OK 150 OK IP 1/IP 2 bellows OK 70 OK 45 OK OK OK Manpower IP 2 platform OK 10 OK Chamber Supports OK 20 In prog LUMI (sigle/bhaba/GEM) OK 45 OK Total 865. 8 In prog. Note (ASTER) tender

Time line

Time line

LHC Upgrade

spare

DAFNE-UP & KLOE

DAFNE-UP & FINUDA

Luminosity and crossing angle + crossing angle q (Piwinski angle F) luminosity is limited by hourglass and tune -shift effects y high density N low by low sx y by by z The introduction of a crossing angle do NOT improve luminosity z

luminosity and tune-shift bat allows to play with transversal dimension sx and by optical function, kipping limited the vertical tune-shift and strongly depressing horizontal tune-shift qsz large sx small bat a large Piwinski angle can generate strong sincro-bethatron oscillation

Performing horizontal oscillations: 1. Particles see the same density and the same (minimum) vertical beta function 2. The vertical phase advance between the sextupole and the collision point remains the same (p/2) upo le Horiz sext ontal oscill ation s Suppression of X-Y Resonances

Increase Positron Current 1. New Injection Kickers 2. New Feedback Systems 3. Ti-Coating

Optical Function

Wiggler linearization CURVED POLE Reduction of the octupole around the beam trajectory in the region of the poles Proposed by Pantaleo MOVING MAGNETIC AXIS Compensation of the integrated octupole in each semiperiod New method S. Bettoni 28/3

Shifted Poles Model For the moment shifted the coils with the poles S. Bettoni 28/3

Analysis of the results: comparison with the experimental data S. Bettoni 28/3