τ- Charm Vacuum System Preliminary La Biodola - Isola d'Elba, Italy 26-31 May 2013 τ- Charm Vacuum System Preliminary Simone BINI, Fara CIOETA, Alberto CLOZZA

Injection System Layout La Biodola - Isola d'Elba, Italy 26-31 May 2013 Injection System Layout τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Vacuum System First hypothesis on: DAMPING RING LINAC TRANSFER LINES La Biodola - Isola d'Elba, Italy 26-31 May 2013 Vacuum System First hypothesis on: DAMPING RING LINAC TRANSFER LINES MAIN RINGS τ- Charm - Injection System Vacuum preliminary S. Bini, F.Cioeta, A. Clozza

Number of Damping Ring Dipoles La Biodola - Isola d'Elba, Italy 26-31 May 2013 Number of Damping Ring Dipoles Damping Ring Parameter Units Value Maximum Beam Energy GeV 1 Maximum Beam Current mA 8 Dipole field T 1.7 Working pressure mbar 1×10-9 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

La Biodola - Isola d'Elba, Italy 26-31 May 2013 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

La Biodola - Isola d'Elba, Italy 26-31 May 2013 Parameter Units Value Total photon flux s-1 6.5×1018 S.R. Desorption coefficient η   1×10-5 Surface specific thermal outgassing mbar l s-1 cm-2 5×10-12 Vacuum chamber inner surface cm2 1×105 S.R. Gas load mbar l/s 2.6×10-6 Thermal Gas Load 3.5×10-7 Total Gas Load 3×10-6 Working pressure mbar 1×10-9 Total needed net pumping speed l/s 3000 Total SR power load W 400 Number of 120 l/s Ion Pumps 36 Total installed pumping speed 4320 Number of UHV gauges 9 Number of gate valves 4 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

DR Vacuum Pumps Positioning La Biodola - Isola d'Elba, Italy 26-31 May 2013 DR Vacuum Pumps Positioning The Hypothesis is to insert a couple of ion pumps on each bending magnet τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

DR Gate Valves and Gauges Positioning La Biodola - Isola d'Elba, Italy 26-31 May 2013 DR Gate Valves and Gauges Positioning Valves (4) Gauges (9) τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

DR Pressure Profile Analysis La Biodola - Isola d'Elba, Italy 26-31 May 2013 DR Pressure Profile Analysis τ- Charm - Injection System Vacuum Preliminary S. Bini, F.Cioeta, A. Clozza

DR Results Vacuum profile La Biodola - Isola d'Elba, Italy 26-31 May 2013 DR Results Vacuum profile Simulations show that a mean pressure of about 3×10-9mbar is expected. The Pressure profile for Damping ring has been simulated for nitrogen gas at 293K, taking into account thermal gas load too. The SIP are assumed to be StarCell 120 l/s, connected to vacuum chamber by means of RF screened ports. τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

LINAC Requirements Zone Pressure RF Gun 10-10 mbar LINAC 10-9 mbar La Biodola - Isola d'Elba, Italy 26-31 May 2013 LINAC Requirements Zone Pressure RF Gun 10-10 mbar LINAC 10-9 mbar RF WAVE GUIDES 10-8 mbar τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Scheme of Pumping System La Biodola - Isola d'Elba, Italy 26-31 May 2013 Scheme of Pumping System Pumping Station τ- Charm - Injection Vacuum System S. Bini, F. Cioeta, A. Clozza

Transfer Lines Requirements La Biodola - Isola d'Elba, Italy 26-31 May 2013 Transfer Lines Requirements TL Pressure 1×10-8 mbar Vacuum Chamber cross section Straight Φ 60 mm PUMPING SPEED 120 l/s every 8 m τ- Charm - Injection Vacuum System S. Bini, F. Cioeta, A. Clozza

Average Working Pressure[mbar] La Biodola - Isola d'Elba, Italy 26-31 May 2013 Main Ring PRELIMINARY Parameters Values Energy [GeV] 2.3 Current LL[A] 1.570 Current HL [A] 2.340 Average Working Pressure[mbar] 1x10-9 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Machine Requirements No specific requests on vacuum pressure La Biodola - Isola d'Elba, Italy 26-31 May 2013 Machine Requirements No specific requests on vacuum pressure Hp: 1x10-9 mbar τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Vacuum System Dimensioning La Biodola - Isola d'Elba, Italy 26-31 May 2013 Vacuum System Dimensioning Γ = 8.08×E×I×1020 (total photon flux) LL HL E=2 GeV I=1.570A I=2.340A ΓL=2.5×1021 photons/s ΓH=3.8×1021photons/s τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Gas Load Distribution along the Machine La Biodola - Isola d'Elba, Italy 26-31 May 2013 Gas Load Distribution along the Machine τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Dipole Magnets As Synchrontron Radiation Sources La Biodola - Isola d'Elba, Italy 26-31 May 2013 Dipole Magnets As Synchrontron Radiation Sources Total Irradiate Power: 216.2627139 [kW] ~ 700 W/m τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

QH=1.5×10-4 mbar l/s Total Gas Load η=1×10-6 (desorption efficiency) La Biodola - Isola d'Elba, Italy 26-31 May 2013 Total Gas Load η=1×10-6 (desorption efficiency) 1mbar l=2.5×1019molec. (conversion factor) Q=Γ η / 2.5×1019 (gas load) QH=1.5×10-4 mbar l/s τ- Charm - Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Mean Pressure & Pumping La Biodola - Isola d'Elba, Italy 26-31 May 2013 Mean Pressure & Pumping <P>≈10-9 mbar (mean working pressure) S=Q/P (pumping speed) SH=1.5×105 l/s (HL total pumping speed) L=325 m S0H= SH/L S0H=460 l/sm (linear net pumping speed) τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Possible Solutions La Biodola - Isola d'Elba, Italy 26-31 May 2013 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

La Biodola - Isola d'Elba, Italy 26-31 May 2013 Pumping System The main process of gas desorption in beam operation is photodesorption i.e. desorption caused by SR In order to evacuate the beam pipes we can use several approaches (all together if possible): A distribuited pumping scheme using a strip-type nonevaporable getter (NEG) and we can use these pumps irrespective of the presence of magnetic fields.(The maximum Pumping Speed is 160l/s )* Lumped NEGs and Sputter Ion Pumps must be used on the straight section . Coating: NEG (Ti-Zr-V), TiN, Graphite *Design and Construction of the SuperKEKB vacuum system – Yusuke Suetsugu,Ken.ichi Zanazawa, Kyo Shibata, Takuya Ishibashi, Hiromi Hisamatsu, Mitsuru Shirai, Shinji Terui – High Accelerator Research Organization (KEK), Japan τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Pumping System Where possible to be verified La Biodola - Isola d'Elba, Italy 26-31 May 2013 Pumping System In order to evacuate the beam pipes we can use several approaches (all together if possible): Dafne Like Vacuum System: Titanium Sublimators Sputter Ion Pumps Synchrotron Light Absorbers Distributed Sputter Ion Pumps inside bendings (Maximum Pumping Speed 165 ls-1m-1* @ 10-8 mbar, no need of any reactivation) Where possible to be verified *References: Brookhaven National Laboratory - Calderon ,PAC_1993 τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

VACUUM CHAMBER DESIGN OF DAFNE WITH SYNCHROTON RADIATION DISTRIBUTION La Biodola - Isola d'Elba, Italy 26-31 May 2013 VACUUM CHAMBER DESIGN OF DAFNE WITH SYNCHROTON RADIATION DISTRIBUTION τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

BARC MAGNET DIPOLE BENDING BARC VACUUM CHAMBER La Biodola - Isola d'Elba, Italy 26-31 May 2013 BARC MAGNET DIPOLE BENDING BARC VACUUM CHAMBER τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Synchroton Radiation into the Bending Magnet La Biodola - Isola d'Elba, Italy 26-31 May 2013 Two main parameters assist to select the vacuum chamber material: the synchrotron radiation power density; the secondary electron yield coefficient. The material that fulfills these requirements is Aluminum. Moreover, a suitable water cooling must be adopted. Synchroton Radiation into the Bending Magnet RF Screen Straight Section Vacuum Pump τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Disadvantages of NEG Coating La Biodola - Isola d'Elba, Italy 26-31 May 2013 Disadvantages of NEG Coating Small absorbiting capacity of the coating can be a problem for relatively high gas-loaded machines; Slow deposition rate and possible sediment Reactivation Process every 8 hours is possible only by heating the vacuum chamber NEG:150°C Aluminum max 130°C τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

Ti27%V47%Zr26% Average Composition : Deposition Rate : La Biodola - Isola d'Elba, Italy 26-31 May 2013 VACUUM PUMPING STUDY OF TITANIUM-ZIRCONIUM-VANADIUM THIN FILMS Yulin Li# and Simon Ho, LEPP, Cornell University, Ithaca, NY 14853, USA Average Composition : Ti27%V47%Zr26% Deposition Rate : τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

DISTRIBUTED NEG CONSTRAINS La Biodola - Isola d'Elba, Italy 26-31 May 2013 DISTRIBUTED NEG CONSTRAINS Activation is required approximately every month for continuos full-current operation (21 days SuperKEKB (Japan)) τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

La Biodola - Isola d'Elba, Italy 26-31 May 2013 WIGGLER If installed on the machine, They are intense Synchrotron Radiation sources. There contribution to gas load must be very carefully evaluated. τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza

2. It’s necessary to evaluate the Vacuum Chamber Impedance La Biodola - Isola d'Elba, Italy 26-31 May 2013 CONCLUSION Many studies remain to be performed to confirm the choices 1. Deep interaction with other Systems (Beam Diagnostics, RF Feedback, Mechanics) is necessary to go ahead with the design of the machine 2. It’s necessary to evaluate the Vacuum Chamber Impedance τ- Charm - Injection Vacuum System Preliminary S. Bini, F. Cioeta, A. Clozza