PEP II Status. H. - Ulrich (UZi) Wienands PEP-II Run Coordinator. SLAGEPAC Meeting November 8,200O. Intro; 11/7/O 19:55

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1 PEP II Status H. - Ulrich (UZi) Wienands PEP-II Run Coordinator SLAGEPAC Meeting November 8,200O Intro; 11/7/O 19:55

2 Run Statistics In CY 2000, PEP delivered 23.6 fb- (86% of 27.3 fb- ) of which BaBar logged 22.1 fb-. Off -resonance running: (logged, incl. in 22.1 fb-l) Including the 1999 run, PEP delivered 2.6 fb fb-. Peak luminosity achieved: 3.1 xl 033 with BaBar logging: 3.02x1 033 Best day: Best week: Best month: 171 pb-l 0.95 fb fb-l Statistics ;11/7/0 19:56

3 25000 PEP-11 Total Delivered Lu

4 Luminosity History Jan 11, Oct. 31,200O Lumi history.cvs; 11/7/O 19:56

5 Typical W-hr delivery period Average length of fill min x10 3 Cwrected Luminosity 10ww3Wcmw3&'5 or &b/s G 1+5 I O+O -0+5 Typical 24hr; 11/7/O 19:57

6 PEP-II Daily Integrated LundmwMy for 20~

7 PEP II Status H. - Ulrich (UZi) Wienands PEP-II Run Coordinator SLAGEPAC Meeting November 8,200O Intro; 11/7/O 19:55

8 Run Statistics In CY 2000, PEP delivered 23.6 fb- (86% of 27.3 fb- ) of which BaBar logged 22.1 fb-. Off -resonance running: (logged, incl. in 22.1 fb-l) Including the 1999 run, PEP delivered 2.6 fb fb-. Peak luminosity achieved: 3.1 xl 033 with BaBar logging: 3.02x1 033 Best day: Best week: Best month: 171 pb-l 0.95 fb fb-l Statistics ;11/7/0 19:56

9 25000 PEP-11 Total Delivered Lu

10 Luminosity History Jan 11, Oct. 31,200O Lumi history.cvs; 11/7/O 19:56

11 Typical W-hr delivery period Average length of fill min x10 3 Cwrected Luminosity 10ww3Wcmw3&'5 or &b/s G 1+5 I O+O -0+5 Typical 24hr; 11/7/O 19:57

12 PEP-II Daily Integrated Lundnas~i~y for 20~

13 PEP-II Weekly Integrated Luminosity for 2000 \ II Q Q Week

14 PEP-II Monthly Luminosity

15 Raisina Luminosity Luminosity equation: => raise beam currents I => lower beam sizes C,... emittances, a* => keep number of bunches b small... until beam-beam limit reached Luminosity;11/7/0 19:57

16 z 0..,A+, Pm & LJ II, 20. hkn Br L6ṛ ma. :, n*, ::+ &#.I. 3. iis > ::. Km..> L?* ZP. 28, **. e.. :x 3. Y L,> 23% Em. :, w /I,I.%.?g: L E r,. k L3.. :b mu. e 16, h. ::,,:, m he.5 1 tl 27. u( * % 1Pb II*. 6. ::. > llxi. R,I), m,i1, cc,. :. 1 2: I %

17 LER Beam BIOWUD LER beam size vs beam current i 1::: 9 * w v i /\ ly 0.59 r* ; I s 1 * I 1 1 I ; 13 * I; 1 I I BEAh CURRENT, A Cflb& ~-i.$ /,i\,+ & 'il/,bl LER blowup.cvs;11/7/0 19:58 1

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21 Backgrounds Managed jointly by BaBar and PEP Protect detector while allowing operational efficiency and machine to be developed Weekly review of beam-abort thresholds SVTRAD doing most of the protection 3 levels of beam abort thresholds & timescales: Fast (ms), protect SVT from p-stop shorts: Chronic : integrated over a few set Timer (5min), protect from lossy injection: 50 mr (Thresholds in effect for most of the run) EMC is limiting injection if too lossy DCH currents have been an issue Collimation works, esp. in LER HER bunches with short lifetimes troublesome Backgrounds; 11/7/O 19:58

22 Accumu SVTRAD : ated Dose and Budget 2000/l 1 /Ol T.Meyer zi PO : I Inner MID ----outer-iviic plane (HERX ;plan.e.(lerj _ ( Radiation Dose Budget e- i Day of Run 2000

23 ~~ ~_~~~~_~_--_-- -Radiation Protection using most sensiiive PIN diodes (in IR horiz. plane) I I I I I / I I I I I All Daily Trips o Dailv Tritx during Stable Beams J 1 BABM 2 60 Tb \.& E= b Day of Year 2000 T. Meyer

24 Issues encountered HER vacuum leaks High-power sr. dump, IR 2b: guard vacuum Flange leak at IR 2b frangible link: guard vacuum Limit HER beam to 650 ma. Rf HV power supplies HV capacitors not rated for high temperatures Two supplies back at vendor for repairs Use test-stand supply to have at least 4 HER rf stations Beam-related heating Bellows: add forced-air cooling Long. feedback components: add heat sinks Vertex chamber: still being investigated, limits 1LER Issues;ll/7/0 19:59

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26 -- PEP-II Downtime Improvements LER rf station 4-3 for beam currents up to 2.8 A LER arc anti-photoelectron solenoids LER longitudinal feedback thermal upgrade handle the higher beam currents HER upstream IR-2 low-pressure chamber known source of backgrounds reduce pressure by = factor of 10 HER high power sr. dump. HER beam separators reduce injection losses. Plans;11/7/0 20:00

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29 The 2001 Run Turn-on Feb. 1, expect one month to recover full operational luminosity Luminosity goal 5x1 033 peak 35 fb-l delivered Run to end Aug. 31,200l 1 c bz* Further upgrades are being pursued Luminosity of 1O34 by the end of 2003 looks feasible Run 2001; 11/7/O 20:02

30 PEP-II Luminosity Upgrade Timeline I J. Seeman for the PEP- II Staff 1 O/9/00 item Upgrade Luminosity Target Activity Hardware Probable Max t&r MaxHER increase luminosity start date ready date luminosity Current Current factor xe33fcm2ls date (A) (A) 1 Starting luminosity 1.oo 2.64 Ott-00 Ott-00 act Near tern? projecfs: 2 Lower betay* (12.5 mm to 9 mm) Ott-00 Jul-00 Mar Raise beam-beam tune shifts to Ott-00 Sep-00 Mar Raise the number of bunches to Ott-00 Ott-00 May-O Third LER RF station (bunches=l024) I Ott-99 Feb-01 Aug Medium term projects: 6 Raise beam-beam tune shifts to Feb-01 Feb-01 Jul Sixth HER Station (bunches=1 125),-I Ott-00 Nov-02 Dee Fourth LER RF Station (bunches=l658) Ott-00 Nov-02 Dee Long term projects: 9 Lower beta y to 5 mm (new IR?) Ott-02 Ott-04 Feb IO Raise beam-beam tune shifts to Ott-02 act-04 Apr Seventh HER RF station Ott-02 Ost-04 Jun Reduce HER bunch length from 9 to 6 mm Ott-02 Ott-04 Jul Fifth LER RF station Ott-02 Ott-04 Ott Improve LER longitudinal feedback Ott-02 Ott-04 Dee Page 1