Status of DA  NE upgrade project C. Biscari for the DA  NE team Napoli -19 september 2005

DA  NE today L peak = 1.53 cm -2 sec -1 Integrated luminosity = 9.4 pbarn September 430 nbarn -1 /hour -> 10 pbarn -1 per day

KLOE FINUDA SIDDHARTA SRFF ? TODAY2008?

Starting point for the accelerator Energy (cm) (GeV) Integrated Luminosity per year (ftbarn -1 ) 8 Total integrated luminosity 203 Peak luminosity > (cm -1 sec -2 ) Collider e+ e-

It is not possible to meet all the requirements of the collider with present DA  NE hardware 3 to 4 years from T o (project approval) needed for R&D, designing, constructing, testing, installing new components 1 year commissioning at low luminosity 2006 T o - Design 2007Design + Construction 2008Construction + Delivery 2009Delivery + Decommissioning + Installation 2010First beam 2011First beam to 1 st experiment

Do we need to modify completely DA  NE?

Even if the possibility to run also at the Φ-energy is taken into account, optimizing the performance in the low energy range is not considered July 2005 Possibility of upgrading the energy in DA  NE up to 2.4 GeV

IR Dipoles Splitters Vacuum chamber Control system Diagnostics Ancillary systems (Injection at 510 MeV keeping the present injection chain) Minimum modifications needed for energy upgrade

Different considerations with respect to G-63 are necessary to increase luminosity at  – energy of one order of magnitude

Total current Rf frequency Crossing angle xx yy Damping time Bunch length

Total current Rf frequency Crossing angle Bunch length NowNew F rf (MHz) Bunch spacing (cm)8460 Bunch spacing (nsec) h NbNb I tot (A) V max (MV)  c max I Boussard (mA)115  l 15 mA 2-31 Lower impedance, higher  E /E, higher  c

xx yy Damping time Beam-beam tune shift

NowNew N (10 10 ) 2.4 – I (A) 1.3 –  x (  rad)  x ( m ) 1.81  y ( cm ) 1.81  L (cm)  (  % ) 1.51  d ( msec ) 3712 I 2 ( m -1 ) 1030 U o ( keV ) 927 P ( kW ) 9 x 5A27 x 2.5A New IR, shorter bunch length, new RF, Lower impedance (e-) Shorter damping time, shielded pc, new IR New wigglers New vacuum system New rf system, higher  c, new lattice

How all these parameters fit in a single machine

One IR Same detector for all experiments Flexibility of lattice, all independent quads New normal conducting dipoles (as in G63) New sc wigglers New sc rf system New layout and vacuum chamber Upgraded injection system Future upgrades Strong rf focusing –  L,  y in the mm range. Ring layout not preventing the possibility of installing harmonic and powerful cavity – test can be done in DA  NE in ( Increase by a factor 4 the luminosity with the same current

IR design

KLOE detector for all experiments Energy (GeV) B det (T) B L (Tm)  rot (°) Transverse plane rotation: Quadrupole rotation different for different energies and/or B det Use of SC low beta quads with skew windings No need of mechanical rotation Technology already used in HERA, BEPC, CESR Strong R&D for ILC 10° Q1 Q2

IR design parameters

IR optical functions E = 0.51 GeV  x * = 1 m  y * = 1 cm  cross = 15 mrad E = 1.2 GeV  x * = 1 m  y * = 2 cm  cross = 12 mrad

Parasitic crossing Beam – Beam tune shift E = 0.51 GeV Bunch spacing 60 cm In the first 1.5 m : 5 pc (every 30 cm) E = 1.2 GeV Bunch spacing 3 m First pc after 1.5 m

Synchrotron radiation integrals Emittance - I 2, I 4, I 5 Damping time - I 2 Energy spread - I 3, I 4 Natural bunch length - I 3, I 4 Emitted power - I 2 Choice of lattice, dipoles, wigglers

Damping time and radiation emission Energy emitted per turn Damping time In DAFNE now: I 2 = 9.5 m -1, U o = 9 keV,  x = 37 msec I 2 = 4.5 dipoles + 5 wigglers

1.8 T Dipole Magnet, POISSON simulation DIPOLES Dipoles per ring12 B (T)0.77 – 1.8  (m) 2.22 Gap (cm)3 Angle (°)26.6(5) 33.3(5) 37.3(1) 22.6(1) Magnetic length (m)1.03 (5) 1.29 (5) 1.45 (1) 0.88 (1) Current (A)150, 430 Choice of normal conducting dipoles Maximum field: 1.8 GeV I 2 = 2.8 m -1

Wigglers are needed to increase radiation and make beam stronger against instabilities by decreasing damping time Once decided the damping time, I 2 is defined: In our case:  x MeV) = 13 msec : I 2 = 26 m -1 L w = B = 4 T With same wigglers and scaled  x =5 msec I 2 = 6.5 m -1

Why wigglers are important? To achieve the short damping times and ultra-low beam emittances needed in LC Damping Rings To increase the wavelength and/or brightness of emitted radiation in synchrotron light sources To increase radiation damping and control emittance in colliders E. Levichev Recent progress in wiggler technology Operating experiences: CESRc, ELETTRA, CAMD R&D in progress: ILC, ATF, PETRA3, …

Emittance Dispersion I5I5 WW DDD Wigglers in dispersive zones increase I 5 and emittance depending on  and D functions. Wigglers in non-dispersive zones increase I 2 and lower emittance

Wigglers influence beam parameters and dynamics: Change the radiation integrals Non-linear effects: affecting dynamic aperture, lifetime, beam-beam behavior The non linear effects are enhanced if the bunch has large transverse dimensions : Large beta functions and dispersion. Placing wigglers in a non-dispersive zone with low betas minimizes non linear kicks.

Good field region centered around wiggler axis Trajectory centered on wiggler axis, independently of E and B Trajectory position with respect to wiggler axis, depends on E and B Usual wiggler design: odd # poles CESRc design: even # poles E = 0.51 GeV E = 1.2 GeV B = 4 T Choice of wiggler shape

Choice of pole length, w Once defined L total and B max Radiation, emittance, energy spread are determined Transverse non-linearities: increase with w Longitudinal non-linearities: decrease with w

Energy spread – bunch length – rf system More radiation – larger energy spread – longer bunch Bunch length can be shortened by increasing h, V Natural bunch length and energy spread at low current are defined by the magnetic lattice, the momentum compaction and the rf system

Short bunch length at high current: Low impedance High  c High voltage Above the microwave instability current threshold  L increases with the current, not depending on  c MEASUREMENTS ON DA  NE

RF system A possible candidate cavity 500 MHz SC cavity operating at KEKB Higher frequencies – lower acceptance Lower frequencies – higher voltage R&D on SC cavities with SRFF experiment in DAFNE

Touschek beam lifetime and natural bunch length as a function of rf voltage (energy acceptance) E (GeV)  E /E (10 -4 ) cc

High currents NOW: I - = 1.8 A I + = 1.3 A routinely Maximum stored current: I - = 2.4 A I + = 1.5 A Experience in Feedbacks Going to 2.5 A – no expected difficulties for e- While e-cloud limiting e+ R&D in progress, simulations, possible cures, possibility of Ti coating DA  NE vacuum chamber Maximum e- current Stored in any accelerator

 N-N Energy per beamE GeV CircumferenceC m 100 LuminosityL cm -2 sec Current per beamI A N of bunchesNbNb Particles per bunchN Emittance  mm mrad Horizontal beta* xx m 11 Vertical beta* yy cm 12 Bunch length LL cm 12 Coupling  % 11 Energy lost per turnUoUo (keV) H damping time xx (msec) 135 Beam PowerPwPw (kW) 62 (55w + 7d)94.6 (42w + 53d) Power per meterP w /m (kW/m) 8.6w + 0.5d8.4w + 3.8d

Two rings One IR SKETCH OF NEW LAYOUT DAFNE HALL KLOE Rf cavities wigglers

Optical functions at  - energy IP Wigglers injection  tuning

IR + section for background minimization DIPOLE 180° Phase advance between last dipole and QF in IR. Particles produced in the dipole will pass near the axis in the quadrupole, and wont be lost Scrapers along the ring to stop particles produced elsewhere Beam direction

Optical functions at 1.2 GeV

Cryogenic system KLOE solenoid Two compensators 4 low beta quads 6 wigglers 2 rf cavities

Injection system Linac + Accumulatore OK Doubling transfer lines for optimizing New kickers (R&D in progress) Ramping for high energy option To be studied the possibility of using on – energy injection for the HE and compatibility with SPARXINO The High Luminosity option needs continuous injection

STUDIES FOR NEW DAFNE INJECTION KICKERS present pulse length ~150ns t t VTVT VTVT Schematic of the present injection kicker system and kicker structure 2 kickers for each ring  ~ 10mrad Beam pipe radius = 44 mm Kicker length = 1m aimed FWHM pulse length ~5.4 ns E=510 Mev # of bunches=120(max) Stored current= A K K K K Courtesy of D. Alesini F. Marcellini

L f - 2L=L B =4 z inj 140mm L r +L f =2D B 1.6m Let’s assume: L r /c=300ps L  680mm L f /c = 5ns (Θ norm =0.69mrad.MeV/cm/kV) GENERATOR REQUIREMENTS (Θ norm =0.69mrad.MeV/cm/kV) t V IN L f /c L r /c Generator pulse shape L r /c Beam energy510 MeV Angle of deflection6 mrad Stripline length68 cm Stripline radius (optimized covarage angle)30 mm Required voltage from pulse generator~65 kV Average power (max rep. rate 50Hz)24.5 W Pulser output current1400A t (2L+L r )/c (L f -2L)/c=L B /c Deflecting voltage V T (2L+L r )/c 2D B EVALUATION OF THE KICKER LENGTH (L) AND THE PULSE SHAPE (Lf, Lr) L f - 2L=L B =0 L  750mm L f /c = 5ns Stripline length75 cm Required voltage from pulse generator ~45 kV Neglecting the bunch length... Courtesy of D. Alesini F. Marcellini

Injection system upgrade The proposed transfer lines pass in existing controlled area Additional shielding needed in the area between the accumulator and DAFNE buildings new e- line new e+ line

Use of DAFNE2 as Synchrotron light source Energy (GeV) Current (A) B dipoles (T) B wigglers (T)4. New scenarios

Tentative costs: 41 M euro including IVA + 10% contingency The option for only energy upgrade: About 22 M euro difference due to Wigglers, rf, cryogenics

Tentative schedule To -> Project approval(2006) To + 1 year ->TDR call for tender To + 2 years ->construction To + 3 years ->construction and delivery, DAFNE decommissioning To + 4 years ->installation and commissioning To + 5 years -> 1 st beam for 1 st experiment (2011) Different experiments must be planned in temporal sequence since they use the same IR

manpower Richiesta di personale in vista dei programmi futuri Servizio Elettronica e Diagnostica N. 1 Fisico o Ingegnere Elettronico N. 1 Diplomato in Elettronica Servizio Impianti a Fluido N. 2 Diplomati Impiantisti Servizio Impianti Criogenici - Servizio Impianti di Potenza e Magneti N. 2 Ingegneri N. 2 Diplomati Elettrotecnica-Elettronica Servizio Impianti Elettrici N. 1 Diplomato Elettrotecnico Servizio Ingegneria Meccanica N. 1 Ingegnere Meccanico N. 2 Diplomati Progettisti Meccanici Sevizio Linac e Sicurezze N. 1 Fisico o Ingegnere Elettronico RF N. 2 Diplomati Elettrotecnica-Elettronica Servizio Radiofrequenza - Servizio Sistema di Controllo N. 2 Fisici o Ingegneri Informatici N. 1 Diplomato Informatica Servizio Vuoto N. 1 Fisico o Ingegnere dei Materiali N. 1 Diplomato Impiantista Per il gruppo di fisica di macchina è inoltre necessario un rinforzo di almeno un paio di giovani fisici. D.A Physicists – Engineers 12 Technicians