antiproton physics experiments

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Antiproton Physics Antiproton Physics Experiments Experiments Keith Gollwitzer -- Fermilab •Antiproton Sources •Accumulator Antiproton Physics Experiments –Precision measurements •Method •Charmonium •XYZ States •Antiproton Physics Experiments Beyond the Accumulator XYZ p p p p D D p p c c p p e e p p p p q q c c p p nMesons p p e H Z p

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Antiproton Physics Experiments. Antiproton Sources Accumulator Antiproton Physics Experiments Precision measurements Method Charmonium XYZ States Antiproton Physics Experiments Beyond the Accumulator. Keith Gollwitzer -- Fermilab. Antiproton Sources. - PowerPoint PPT Presentation

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Page 1: Antiproton Physics Experiments

Antiproton Physics Antiproton Physics ExperimentsExperiments

Keith Gollwitzer -- Fermilab

•Antiproton Sources•Accumulator Antiproton Physics Experiments

–Precision measurements•Method•Charmonium•XYZ States

•Antiproton Physics Experiments Beyond the Accumulator

XYZpp

ppDDpp ccpp

eepp

pp qqccpp

nMesonspp

eHZp

Page 2: Antiproton Physics Experiments

Yearly Production

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Year

e10

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ipro

tons

CERN FNAL

Antiproton SourcesAntiproton Sourcese1

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ear

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tons

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YearYear

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Fermilab and CERN have/had the only Antiproton Sources.Currently, the operating Antiproton Sources are used for the Tevatron low energy/trapping programs, respectively. Schedules beyond 2010 do not exist for either Antiproton Source.

GSI (Darmstadt, Germany) is to construct an Antiproton Source as part of the Facility for Antiproton and Ion Research project. At the design peak production rate, FAIR will make <1014 antiprotons/year starting ~2016.

Fermilab has the best Antiproton Source now and the future

Page 3: Antiproton Physics Experiments

Accumulator Antiproton Accumulator Antiproton PhysicsPhysics

• Precision measurements of Charmonium

• Precision measurements of XYZ States

• Measurements of continuum processes– Associated production of

Charmonium– Proton Form Factor– Multi-meson final states

• Searches/confirmations – Excited Charmonium

states, – Exotics/hybrids – Glueballs

• Partial Rate Asymmetries of Hyperon Decays– CP violation

• Rare Hyperon Decays– Dimuon resonance search

• Relativistic Antihydrogen– Lamb Shift

• Open Charm– D-mixing; CP violation

• Charmonium produced in different nuclear targets

• Polarized hydrogen target – Electric and magnetic

contributions to the Proton Time-like Form Factor

Page 4: Antiproton Physics Experiments

Beam Profiles

Breit-Wigner line shape

Beam Scan of ψ(2S)

Most precise measurement of the ψ(2S) width despite

much smaller statistics than e+e- experiments

Precision Measurement Method

Convolution results in the

observed cross section

Page 5: Antiproton Physics Experiments

The precision of the mass and width of the c needs to be improved

E760 & E835 only reported pbarp

Need to observe c in more channels

Page 6: Antiproton Physics Experiments

1P1 or hc JPC = 1+-

The hc mass is important to understanding hyperfine splitting.

The hc width has not been measured. Need more channels.

pbarp hc c ()

E760: pbarp hc J/ 0 (e+e-) ()

Page 7: Antiproton Physics Experiments

Searched for pbarp ηc/

PDGM = 3637 ± 4 MeVГ = 14 ± 7 MeV

Need more channels.

Page 8: Antiproton Physics Experiments

Also in March 2008 CERN Courier

Study in pbarp in the A

ccumulator?

Page 9: Antiproton Physics Experiments

X(3872) has been seen to decay via Charmonium and Charm Mesons

resulting in different masses. 1 or 2 states? Only upper limit on width.

Accumulator could scan this resonance(s)

Page 10: Antiproton Physics Experiments

Charmonium ReactionsCharmonium Reactions

0/ Jpp

pppp // Jpp c

eeψJpp /

/Jpp /0 Jpp c

/cpp

pppp c /

/cpp

0cpp

0cpp

pphpp c

pppp c 0

2cpp 2cpp

0/Jhpp c

/Jpp

/1 Jpp c

pppp c 2

pppp c 2

ppJpp /

ccpp /

/cpp

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cpp 0cpp 2cpp

eeψpp

/2 Jpp c

pppp c

cpp

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0/Jhpp c

Page 11: Antiproton Physics Experiments

XYZ ReactionsXYZ Reactions

pp X(3872) D0D00

pp X(3872) D0D*0

pp Z(3930) D Dpp X(3940) D*Dpp X(4160) D*D*

pp X(3872) J/ pp X(3872) J/ pp X(3872) J/ pp Y(3940) J/ ωpp Y(4008) J/ pp Y(4260) J/ pp Y(4260) J/ KK

Page 12: Antiproton Physics Experiments

pp J/ 0

pp J/ ωpp c 0

pp c ωpp c0 0

pp c1 0

pp c2 0

pp / 0

pp c/ 0

pp 0pp

pp J/ pp J/ /

pp c pp c /

pp c0 pp c1 pp c2 pp / pp c

/ pp pp ω

pp J/ pp J/ pp c pp c pp c0 pp c1 pp c2 pp / pp c

/

pp 0ωpp /ω

pp 0pp 0/

pp 00

pp /

pp /

pp //

pp ωpp ωω

pp φφpp KK

pp

eeppContinuum ProcessesContinuum Processes

Page 13: Antiproton Physics Experiments

Facilities Beyond the Facilities Beyond the AccumulatorAccumulator• Low Energy Ring/Stopping

– Decelerate in MI and extract to new ring capable of further deceleration and cooling

• Slow Antiprotons and Trapping• Antihydrogen and Antiprotonic Atoms

• Medium Energy Ring– Accumulator freed from experiment to stack full

time– Extend energy reach of experiment; electron

cooling?• Bottomonium

– Precision Measurements– Small collider (asymmetric?) – Internal jet target (50-70GeV/c)

Page 14: Antiproton Physics Experiments

SummarySummary• The world’s most productive Antiproton

Source is here at Fermilab and could continue to be for the next decades

• The Fermilab Accumulator has hosted successful experiments

• The Fermilab Accumulator can be ready to perform experiments ~6months after Run II

• Many different measurements can be made• First physics results could be in 2011• New rings could exploit the Fermilab

Antiproton Source capabilities.

Page 15: Antiproton Physics Experiments

Extra Slides

Page 16: Antiproton Physics Experiments

Charmonium Masses and Widths11

F i g u r e1 . 7 :Thecharmoniums pectrumbe l ow t h eopencharmt h r e s h o l dwitht h e1P1

l oc a t e da tt h es p i nwe i g ht e dave r a g eo ft h et r i p l e tP wave s t a t e s .Thick s o l i dl i n e s

d e n o t et h es t a t e swhich a r ed i r e c t l yp r oducedby e+e# a n n i h i l a t i o n ;s t a t e swhichwe r e

unseeno rneededt obe ve r i f i e dbe f o r et h i sexperiment a r er e p r e s e nt e dby t h i ckbrokenl i n e s .Theknown andexpe c t e dh a d r o n i cande l e c t r o m a g n e t i ct r a n s i t i o n sanddecay st h a tE760cand e t e c ta r es h own.

E760/E835 main purposes were to do precision measurements of the

Charmonium spectrum as well as the

discovery/confirmation of 1P1 and ηc

/

Page 17: Antiproton Physics Experiments

TechniqueThe Accumulator is the Spectrometer

Annihilation of pbar p to form each state

All quantum numbers can be formed

Detector is a big scalar

Scan beam energy to map out resonance

Page 18: Antiproton Physics Experiments

“Clean” electron/positron Signals

/ J/ X e+e- X

/ e+e- Threshold CernekovShower shape

Page 19: Antiproton Physics Experiments

1-- State Scans (1990-1)

Page 20: Antiproton Physics Experiments

PRECISION

PRECISION

PRECISION

PRECISION 1 & 2 Scans

Page 21: Antiproton Physics Experiments

0 Scan

Could be more precise with more integrated luminosity

Interference will be shown later

Page 22: Antiproton Physics Experiments

pbarp 0 0

0

Two Photon Final States

Takes work to understand the feed-

down from multi-photon final states

CCAL threshold of 5/20MeV

These data are from the c peak

Page 23: Antiproton Physics Experiments

pbarp 0 & 2 In

terfe

renc

e ne

xt s

lide

Page 24: Antiproton Physics Experiments

Interference can be your friend

The continuum “amplifies” the resonance

E835 example in 4 photonspbarp c0 0 0 , , /

Should expand interference analyses to

more channels; in particular pbarp at 90o

in the center of mass system

Page 25: Antiproton Physics Experiments

Search using inclusive J/

c/ s

earc

h fo

r pos

sibl

e hi

nder

ed

M1

trans

ition

to J

/

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imum

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umul

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rist P

oint

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ent

Page 26: Antiproton Physics Experiments

The States

J PC

1 - -

2 + +

1 + +

? ? ?

/0 12

c c/hc

Page 27: Antiproton Physics Experiments

pbarp +

Page 28: Antiproton Physics Experiments

pbarp two neutral mesons

00 0

Page 29: Antiproton Physics Experiments

Scaling Rule?

Page 30: Antiproton Physics Experiments

pbarp two neutral particles

Page 31: Antiproton Physics Experiments

Proton Magnetic Form Factor

Page 32: Antiproton Physics Experiments

pbarp 6

Page 33: Antiproton Physics Experiments

Steering Group Report• P19 Precision Physics – muons: “An intense 8 GeV beam and the

Accumulator and Debuncher rings, …, would make this LFV search possible.”

• P20 Precision Physics – Charm and hyperon physics with antiprotons (1 paragraph sub-section)

• P24 SNuMI: “SNuMI uses antiproton facilities….”• P25 Project X: “…compatible with reconfigurations of the Debuncher

ring and the Tevatron to support slow spill programs….”• P25 Existing Rings: Debuncher Slow Extraction (1 paragraph sub-

section)• P27 Summary paragraph: “The SNuMI project is based on reusing

existing antiproton rings for proton accumulation.”• P44 Appendix G Facilities Considered: table entry of Antiproton

Facility with Performance Parameters of “Incompatible with SNuMI. Minor hit on proton availability from Project X”

• Most overview presentations of the Steering Group Report and Project X spend time discussing reusing the Antiproton Source rings (sometimes even emphasizing existing accelerator) with little or no mention of Antiproton Physics