F Tevatron Operations Ron Moore DOE Tevatron Operations Review March 27, 2007 SC-1 Breakout.

f

Tevatron OperationsTevatron Operations

Ron MooreDOE Tevatron Operations Review

March 27, 2007SC-1 Breakout

2007 DOE Tevatron Operations Review – R. Moore 2

f Since the 2006 shutdown ended…Since the 2006 shutdown ended…

209 HEP stores (give/take a few…not counting ones lost before HEP)

Record delivered lumi / week 24.4 → 44.9 pb-1

Record peak luminosity 180 → 292 1030 cm-2 s-1

Record # pbars at start HEP ≈ 3072 109

Delivered > 1 fb-1 to CDF and D0

Run 2 total delivered now > 2.6 fb-1, recorded > 2.0 fb-1


f Run II Peak LuminosityRun II Peak Luminosity


f 2006 Tevatron Shutdown Tasks2006 Tevatron Shutdown Tasks

Fixed known cold leaks in E2, A3, B4; replace failed dipole in F4

Replaced all ≈1200 LHe Kautzky valves

Cause of 2 magnet failures prior in Nov 06 and Feb 07

Completed reshimming on remaining 228 dipoles

Needed 3 shutdowns to do! Cryostat sagging – causing coupling

Unrolled quads in A3 (~10 mrad); unroll ~60 magnets with small rolls

Installed 2 new separators (B48, A17), replace 3 separators (A49)

Repaired TEL-1 and installed TEL-2

Pulled cables for new sextupole circuits (2nd order chromaticity correction)

Completed IPM detector installation

Completed ring-wide hydrostatic level sensor installation

Many smaller tasks, lots of maintenance…

Smooth start-up after such a long shutdown

Run II upgrades effectively complete


f Highlights since 2006 ShutdownHighlights since 2006 Shutdown

More pbars to HEP Thanks to Pbar Source and Recycler

More protons to HEP Injecting more protons Better lifetime @ 150 GeV from new helical orbit

Improved luminosity lifetime Additional separators increase beam-beam separation

Commission TEL-2 Spare abort gap cleaner & demonstration of beam-beam

compensation

Smooth orbits to desired HEP position every store Improvement on orbit stabilization

Faster halo removal – save few minutes Get to HEP sooner

Online luminosity fits and model comparison New tools based on SDA/SuperTable data


fBeam Intensities at Injection

0

500

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4300 4500 4700 4900 5100 5300

Store #

Pb

ar In

ten

sity

[E

9]

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1000

2000

3000

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6000

7000

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9000

10000

11000

12000

Pro

ton

Inte

ns

ity

[E

9]

Pbar

Proton

Injecting More Proton and PbarsInjecting More Proton and Pbars

2006

shu

tdow

n


fBunched Beam Inefficiency @ 150 GeV

-5

0

5

10

15

20

25

30

4300 4500 4700 4900 5100 5300

Store #

Inef

fici

ency

[%

]

Pbar

Proton

Improved Proton Efficiency @ 150 GeVImproved Proton Efficiency @ 150 GeV

2006

shu

tdow

n


fProton Inefficiency @ 150 GeV

0

5

10

15

20

25

30

500 1000 1500 2000 2500 3000 3500 4000

Pbar Intensity @ Injection [E9]

Pro

ton

Inef

ficie

ncy

[%

]

Dec 04 - Feb 06

Jun 06 -

Last 10 Stores

Last Store

Improved Proton Efficiency vs Pbar Improved Proton Efficiency vs Pbar IntensityIntensity

New injection helix increased separation between beams

(Yu. Alexahin)


f FY07 Integrated LuminosityFY07 Integrated Luminosity

D32-5 failurefeeder 46B

fault

E39/43 vacuum failure

A18 vacuum leak


fBeam Intensities at Start of HEP

0

500

1000

1500

2000

2500

3000

3500

4000

4500

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5500

4300 4500 4700 4900 5100 5300

Store #

Pb

ar In

ten

sity

[E

9]

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11000

Pro

ton

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ity

[E

9]

Pbar

Proton

Getting More Proton and Pbars to HEPGetting More Proton and Pbars to HEP

2006

shu

tdow

n


f Long-range beam-beam effects degrade lumi lifetime +

integral Nearest parasitic crossings (≈59 m from IPs) especially bad

Additional separators installed to allow increased separation More separation reduced beam-beam effects

~20% increase @ upstream IP

Not as much @ downstream IP

Luminosity lifetime improved ~20% compared to pre-shutdown Increased integrated luminosity per store (for similar

luminosities and store lengths)

Luminosity LifetimesLuminosity Lifetimes


f Comparing HEP Stores to Model Comparing HEP Stores to Model withoutwithout Beam- Beam-BeamBeam

After shutdown, luminosity

evolution agrees better to

model without beam-beam

effects

Most pbars lost during HEP

are burned in luminosity

That’s good!

Protons suffer more from

beam-beam effects

Especially with smaller

pbars

V. Lebedev


f Better Lifetime Better Lifetime More Delivered Luminosity More Delivered Luminosity

Normalized Lumi Integral / 24 hr vs Initial Luminosity

0

10

20

30

40

50

60

0 50 100 150 200 250 300

Initial Luminosity [1030 cm-2 s-1]

Lu

mi

Inte

gra

l /

Init

ial

Lu

mi

[n

b-1

per

24

hr

/ 10

30 c

m-2

s-1

] Dec 04 - Feb 06

Jun 06 -

Based on luminosity lifetime fits and adjusting to 24 hour store

duration


f Bunch-by-Bunch Tune Shifts: Store 5245Bunch-by-Bunch Tune Shifts: Store 5245

Higher pbar intensities proton/pbar head-on tune shifts ≈ equal! Proton / pbar intensity ≈ 3, but proton/pbar emittance ≈ 3, too!

Consistent beam intensities store-to-store is helpful operationally Otherwise, tune changes needed in advance to prevent lifetime problems Pbar intensities vary more - lost stores, problems in upstream machines, etc.

Bunch leveling in Recycler also helpful for Tevatron and experiments More uniform bunch dynamics, more uniform bunch-by-bunch luminosity


f Tune FootprintTune Footprint

Currently operate between 7/12 and 3/5 for collisions

Considering moving near ½

integer


f Beam LifetimesBeam Lifetimes

Pbar lifetime dominated by luminosity – good Most protons lost in non-luminous processes – not so good

Luminosity[μb-1/s]

Pbar Lifetime

/ ExpectedLifetime from

Luminosity

Store 5245

Proton Lifetime

/ ExpectedLifetime from

Luminosity


f Smaller Pbar Emittance Smaller Pbar Emittance Worse Proton Lifetime Worse Proton Lifetime

Non-Luminous Proton Lifetime vs Pbar Horz FW Emittance since June 2006 (first 2 hrs of HEP)

0

50

100

150

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350

400

0 2 4 6 8 10 12 14

Pbar Horz FW Emittance @ Remove Halo

Pro

ton

No

n-L

um

ino

us

Lif

etim

e [

hr]

Proton Non-Lumi


f

0 1 2 3

Beam-beam force Proton density Antiproton density

r/

Schematic of Beam-Beam Force on Proton BunchSchematic of Beam-Beam Force on Proton Bunch


f Example of Tight Tune Space for ProtonsExample of Tight Tune Space for Protons

Operator error – tune pushed too high

Longitudinal shaving

Store 5008 L = 207


f Store 5245 – Comparison to Model w/o Beam-Store 5245 – Comparison to Model w/o Beam-BeamBeam

Initial Lumi = 286 μb-1/s

~10% loss from beam-beam


f ReliabilityReliability

Replaced all He Kautzky valve poppets in 2006 shutdown

Successfully tested higher bandwidth quench protection electronics (VFCs) Implemented in 3 houses, gradually propagate to whole ring

Helps detect quench and pull abort in ≈350 μs (< 20 turns)

Migrated control applications from VMS to Linux A BIG job requiring careful testing and implementation in operational

environment

2 Tevatron failure-driven shutdowns since June 2006 Mouse-induced feeder glitch resulted in D3 dipole failure (Oct)

Failed O-ring caused loss of E3 cryo insulating vacuum (Nov)

New pbar cogging for ramp since early Jan 2007 Pbars were in the abort gap previously – quench if abort up ramp

Now clear abort gap should prevent needless quenches (OK in only “trial” so far)

Implement new BLM electronics to allow aborts on high beam losses Current system too inflexible – BLM aborts masked out during HEP


f Tevatron ReliabilityTevatron Reliability

Collider Run II ReliabilitySince 2006 Shutdown

0

24

48

72

96

120

144

168

274 276 278 280 282 284 286 288 290 292 294 296 298 300 302 304 306 308 310 312 314

Run II Week #

Ho

urs

Store Hours Set Up Studies Shutdown Failure Miscellaneous


f Integrated Lumi and Store Hours per Integrated Lumi and Store Hours per WeekWeek

5 store running average scaled to 1 week


f Looking AheadLooking Ahead

Implement 2nd order chromaticity correct @ low β Correct second-order chromaticity @ low β better lifetime

Also required for possible new working point (near ½ integer)

Work with experiments in optimizing integrated vs peak luminosity Multiple interactions cause difficulties for trigger and tracking

When is peak too high? Do we need higher intensities afforded by new working point?

Other minor improvements – they all add up! Scrape (higher intensity) protons @ 150 GeV

• Remove beam that would be lost anyway on ramp and squeeze

• Get “brighter” protons to HEP

Investigating new cogging between pbar injections• Reduce beam-beam effects by changing locations of long-range crossings

• Improve proton lifetime @ 150 GeV (bunch-dependent)

More reliable tune measurements• New 1.7 GHz Schottky electronics designed by FNAL (LARP) for LHC (better dynamic range)

• New digital tune monitor to measure individual bunches (with tickling)

Better helices, improved transfer line matching, faster shot-setups, etc.


f New Sextupole CircuitsNew Sextupole Circuits

Move 22 elements from existing SF&SD circuits to 12 new circuits

Correct 2nd order chromaticity in low-β lattice Should reduce non-luminous proton losses

Operational with new power supplies since early February Cables pulled during 2006 shutdown Still configured as “normal” chromaticity sextupoles

Conducting proton-only studies to implement in final configuration

New circuits to run at zero current except @ low-β Need short access to flip polarity of some elements when ready Could be operational in ~1 month

Simulation results in Alex Valishev’s slides


f Luminosity ProjectionsLuminosity Projections

Refer to slides in R. Dixon’s talk

Projections assume ≈100 store hrs/week on average Takes into account possible unplanned downtime (failures)

Based on current pbar stacking rate, appear on track to deliver 5.5-6.5 fb-1 total

Likely need increased stacking rates to go higher

Approaching design 320 μb-1/s peak luminosity Consult with experiments if higher is OK for them

Goal is to maximize integrated luminosity on tape


f Integrated LuminosityIntegrated Luminosity

0

1

2

3

4

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7

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9

10

9/29/03 9/29/04 9/30/05 10/1/06 10/2/07 10/2/08 10/3/09

Date

Inte

gra

ted

Lu

min

osi

ty (

fb-1)

30mA/hr25mA/hr20mA/hr

Peak Pbar Stacking

Rates

We’re in this area now2.6 fb-1

≈22 mA/hrMarch ‘07


f One Example of Model ParametersOne Example of Model Parameters

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5

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25

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40

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Store Length (Hours)In

tegr

ated

Lum

inos

ity

per

Wee

k (

pb

-1)

2 Transfers

3 Transfers

4 Transfers

5 Transfers

6 Transfers

7 Transfers

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5 10 15 20 25 30 35 40

Store Length (Hours)

Init

ial

Lu

min

osi

ty (

b-1

/sec

)

2 Transfers

3 Transfers

4 Transfers

5 Transfers

6 Transfers

7 Transfers

In general, weekly integrated luminosity ≈ independent of store length in 20-30 hr range → flexible running schemes

Pbar stacking rate important factor


f SummarySummary

Tevatron delivering record peak and delivered luminosity Great start-up following long 13-week shutdown Higher beam intensities to HEP, improved lifetime

Protons suffering more from beam-beam effects Operationally challenging to stay in desired tune space when

pbar intensities vary from store-to-store

Implementing 2nd order chromaticity compensation circuits Should improve lifetimes in collisions Prerequisite for investigating ½ integer working point

Maximize integrated luminosity to CDF and D0 On track for 5.5-6.5 fb-1 at current pbar stacking rates Let’s find the Higgs!


f Backup SlidesBackup Slides


f

Accelerator Highest Energy

Cockroft Walton 750 keV

Linac 400 Mev

Booster 8 GeV

Main injector 150 GeV

TEVATRON 980 GeV

NuMI (120 GeV)MiniBoone

(8 GeV)

P1 Line

A1 Line


f FY Integrated LuminosityFY Integrated Luminosity


f FY07 Peak LuminosityFY07 Peak Luminosity


f FY05-FY07 Weekly Integrated LuminosityFY05-FY07 Weekly Integrated Luminosity

5 store running average scaled to 1 week


f FY 2007 Average Store Hours per WeekFY 2007 Average Store Hours per Week


f Machine Studies and MaintenanceMachine Studies and Maintenance

Averaged ≈6.5 hrs / week since last shutdown

Does not include parasitic studies

Exploit natural breaks in machine operation

Lost stores, pbar stacks, etc.

Exploit end-of-store studies

Focus on specific, well-prepared studies

Be efficient, prevent unnecessary quenches/downtime

Start with proton-only stores before trying in HEP

If we really need study time to implement something

new for HEP, will get the time

e.g., proton-only for commissioning new sextupole circuits


f Bunch-by-Bunch Proton Losses @ 150 Bunch-by-Bunch Proton Losses @ 150 GeVGeV

Lifetime of a proton bunch degrades when it has a parasitic crossing with

pbar bunch near B13

Proton #1 [E9]

Proton #19 [E9]

PbarInt. [E9]

Pbar cog [bkts]

Proton #22 [E9]

Proton #34 [E9]


f New Injection HelixNew Injection Helix

Increased separation at “worst” parasitic crossing

20 40 60 80 100 120 140

3

4

5

6

7blue – old red – present

Parasitic Crossing Number (from B0)

Sep

ara

tion

in

σ


f New Collision HelixNew Collision Helix

After adding the A17H and B48V separators in 2006 shutdown

blue – old red – present

Distance from B0 [m]

Sep

ara

tion

in

σ


fNormalized Lumi Integral / 24 hr vs Initial Luminosity

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

0 50 100 150 200 250 300

Initial Luminosity [1030 cm-2 s-1]

Lu

mi

Inte

gra

l [n

b-1

per

24

hr

]

Dec 04 - Feb 06

Jun 06 -

Better Lifetime Better Lifetime More Delivered Luminosity More Delivered Luminosity

Based on luminosity lifetime fits and adjusting to 24 hour store

duration


f Separation at IPs with different cogging at injection

222

221 )/()/(),,max(/ yxyx yxSyxS

S1min

S2min

Injection cogging ncog=61

ncog - cogging w.r.t. the collision one, ncog=0

Measured helix and optics used, reference emittance 15mmmrad


f Beam-Beam Resonance Strengths vs Injection Beam-Beam Resonance Strengths vs Injection CoggingCogging

Nominal values @ injection ncog=61 (before change)

Collision cogging: ncog=0

ncog=-2 is the best for

7Qy

ncog=10 is good for 5Qx

while not bad for 7Qy

5Qx

7Qy

ncog RDTs (Resonance Driving Terms) calculated for 3 amplitudeYuri Alexahin

Now implemented for

ramp


f Kautzky Valve PoppetsKautzky Valve Poppets

During quench, pressure forces valve open, allows He to escape

Poppet can break off, remain in closed position

1 similar failure in 20 years, then 2 in three months

→ Replaced all ≈1200 He Kautzky valve poppets during 2006 shutdown

No poppet failures since replacement

Closed Kautzky valveBroken poppet from B17

spool Kautzky valve


f Online Luminosity Evolution FitsOnline Luminosity Evolution Fits

Bunch-by-bunch lumi and beam intensities, too

Different fit functions and results stored in database, spreadsheets, etc.

Useful for Run Coordinator to determine end-of-store time


fD32-5 dipole beam tube

Holes from

arcing

Flashover in Feeder 46B cubicle

D32-5 Dipole Failure in Oct 2006D32-5 Dipole Failure in Oct 2006

Mouse caused feeder fault Glitch → D3 quench response Dipole failed during quench Previous D3 quench 9/11/02

Failure lying in wait?


f Tevatron Electron Lenses (TEL)Tevatron Electron Lenses (TEL)

TEL-1 installed 2001; repaired & reinstalled 2006 Used mainly to clean abort gap Few studies demonstrating (horz) compensation on pbars (2003) Test bed for electron gun designs

TEL-2 installed 2006 Used as spare abort gap cleaner Successful (vertical) tune-shifting on protons during HEP!

TEL-2

TEL-2 on P12


f TEL-2 in ActionTEL-2 in Action

TEL-2 increases proton lifetime by raising vertical tune away from 7/12 TEL-1 could do same for horz tune on leading bunches of train

Little emittance growth, little/no increase in losses Currently doing studies with TEL-1 while TEL-2 cleans abort gap Could try simultaneous operation to level bunch tunes to help lifetime TEL-2 Marx generator suffers from radiation damage – added steel shielding

TEL-2 ON P12

TEL-2 off

P12/24/36 lowest vertical tune

(PACMAN) P12 intensity

[E9]

P36 intensity

[E9]


f IPMIPM

Detectors installation completed during 2006 shutdown Waiting for full complement of production electronics Observed TBT quadrupole oscillations on injection

Will improve transfer line matching, emittance dilution

Protons & Pbars at InjectionProton Bunch Injection Oscillations

Turn #0 20

1

2

RM

S s

ize

[mm

]


f Peak LuminosityPeak Luminosity

0

50

100

150

200

250

300

350

9/29/03 9/29/04 9/30/05 10/1/06 10/2/07 10/2/08 10/3/09

Date

Pea

k Lu

min

osity

[m b

-1/s

]

30mA/hr25mA/hr20mA/hr

Peak Pbar Stacking

Rates


f Delivered Luminosity per WeekDelivered Luminosity per Week

0

10

20

30

40

50

60

9/29/03 9/29/04 9/30/05 10/1/06 10/2/07 10/2/08 10/3/09

Date

Inte

gra

ted L

um

inosi

ty p

er

We

ek

(pb-1

) 30mA/hr25mA/hr20mA/hr

Peak Pbar Stacking

Rates

F Tevatron Operations Ron Moore DOE Tevatron Operations Review March 27, 2007 SC-1 Breakout.

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Transcript of F Tevatron Operations Ron Moore DOE Tevatron Operations Review March 27, 2007 SC-1 Breakout.