future of hadron physics experiments at j-parc k. ozawa (kek) contents: j-parc & hadron facility...

Future of Hadron Physics Experiments at J-PARC

K. Ozawa (KEK)

Contents:J-PARC & Hadron FacilitySome topics at J-PARC and related Facility(Future plan of J-PARC & Hadron Facility)Summary

2014/10/25 K. Ozawa, Hadrons in nuclear medium 2

Nara

J-PARCTokyo

KEK

600km


J-PARC (Japan Proton Accelerator Research Complex)

J-PARC (Japan Proton Accelerator Research Complex)

Tokai, JapanTokai, Japan

MR30 GeV Synchrotron

400 MeV LinacRCS

3 GeV Synchrotron

Material and Life Science Facility

Neutrino Experimental Facility

Hadron Hall60m x 56m

Hadron Experimental Facility

30 GeV Accelerator & Hadron Experimental Facility


30GeV proton Accelerator

Branch Point from Acc. to Hadron

Transfer Line from Acc. to Hadron


Current Production target for secondary beams

New Beamline (under construction)

K. Ozawa, Hadrons in nuclear medium 5


K1.8BR

KL

K1.8

K1.1High-p

COMET

Name Species Energy IntensityK1.8 p±, K± < 2.0 GeV/c ~105 Hz for K+

K1.8BR p±, K± < 1.0 GeV/c ~ 104 Hz for K+

K1.1 p±, K± < 1.1 GeV/c ~ 104 Hz for K+

High-pproton 30GeV ~ 1010 Hz

Unseparated < 20GeV/c ~ 108 Hz

2014/10/25

Under Construction

What we know about hadrons?• Colored quarks are confined.• u, d, s quarks are no longer light.• Pseudo-scalar mesons are light. • Flavor SUf(N) symmetry exists

2014/10/25 6

What we naively think? Perturbative region• Current quark• SUL(N) X SUR(N)

Nonperturbative region• Constituent quark• SUV(N)

• Dynamical mass generation• the presence of p, K, h

as NG bosons

SSB

K. Ozawa, Hadrons in nuclear medium

Puzzles in hadron physics• Missing resonances.• States cannot be easily explained by a quark model.

(e.g. Roper, L(1405), …)• Unexpected states. (e.g. narrow resonances at Belle)

2014/10/25 7

What we want to know?• What are inside structures of hadron?

Constituent quark?, Di-quark? Hadron as a constituent of hadron?

• How can hadrons interact with other hadrons ?• How mass is dynamically generated?


Aspects of hadron physics


Inside Structure

QCD Phase Diagram

Hadron-Hadron Interaction

Building blocks? Interaction btw building-blocks in hadron

QCD medium and hadron properties

Interaction btw “color-less” particles

These aspects are strongly related,

especially in interpretations of

experimental results

We should aware of the difference


• Fundamental Reactions– g+N, N+N, p+N, e+N

• Nuclear Target – g+A, N+A, p+A, e+A

• Heavy Ion Collisions

Inside Structure

Hadron-Hadron

Interaction

QCD Phase

Diagram

• When we found an interesting object for our physics, then we should take all data below, because effects of these aspects should be figured out.– Each reaction and energy has a suitable physics explanation.

• If we could have a “standard model” for all reactions, it would be happy. However, it’s difficult, I think.

h’


• Physics:– It is a very interesting object in terms of partial restoration of chiral

symmetry• (I omitted other interesting object, p meson. Sorry.)

• Past, On-going, and Future Experiments:– Fundamental reactions

• pp @ COSY • gp, gd @ BGOegg – Spring-8• pp @ J-PARC (LOI)

– Nuclear target• p-He results @ COSY• 12C(p,d) reaction @ GSI and Future FAIR• g-C reaction @ BGOegg

– Heavy Ion Collisions• Large mass reduction in AA collisions at sNN = 200 GeV

– T. Csorgo et al., Phys. Rev. Lett. 105 (2010) 182301


LOI: Measurements of π-p→η n ′• h’ meson is interesting

– Related to UA(1) anormaly– Large mass reduction is expected in nucleus, theoretically.

• η N interaction is important as a basic information, however, ′current experimental data seems contradictive– weakly interacting?

←COSY-11 (pp→ppη′), |aη N′ |~0.1fm– strongly attractive?

←near-threshold cross section of π-p→η n ′ reaction (against s-wave behavior: σ/p*=const.)

• indicating N* resonance near η N threshold?′

• Precise measurement at J-PARC– with γ detector and neutron counter

2014/10/25

PLB482, 356 (2000)

arXiv: 1109.0394PLB709, 87 (2012)

Nuovo Cimento A75, 163 (1983)

H. Fujioka

h’


• Physics:– It is a very interesting object in terms of partial restoration of chiral

symmetry• (I omitted other interesting object, p meson. Sorry.)

• Past, On-going, and Future Experiments:– Fundamental reactions

• pp @ COSY • gp, gd @ BGOegg – Spring-8• pp @ J-PARC (LOI)

– Nuclear target• p-He results @ COSY• 12C(p,d) reaction @ GSI and Future FAIR• g-C reaction @ BGOegg

– Heavy Ion Collisions• Large mass reduction in AA collisions at sNN = 200 GeV

– T. Csorgo et al., Phys. Rev. Lett. 105 (2010) 182301 • We should keep our collaborations and competitions• Guidance of theorists may must be important

L(1405) and K-pp• Physics:

– Interplay of hadron-hadron interactions and inside structure

• Experiments:– Many many experiments

• At J-PARC, E15 and E31 are on-going.

– Another results from J-PARC • Y. Ichikawa et al., Inclusive spectrum of the d(π+, K+) reaction

at 1.69 GeV/c, Prog. Theor. Exp. Phys. (2014) 101D03– Inclusive spectrum only. Exclusive histogram and ratio will come next.

– Future physics extension• K-K-pp


Future exp: K-K-pp bound states

• K-pp bound states are studied at K1.8/BR (E27/E15). As a physics extension, K-K-pp bound states are also predicted theoretically.

• Produce the system using high momentum (~8GeV/c) proton beam and double L* production.


Experiment

Missing Mass

Invariant Mass

F. Sakuma

Vector Mesons in nucleus • It seems Jido-san said “We don’t need condensates!”. However,

Let’s start with a discussion btw vector mesons and condensates


Relations between mass spectra of V-AV mesons and condensates is developed using a sum rule.

Hatsuda, Koike and Lee, Nucl. Phys. B394 (1993) 221Kapusta and Shuryak, Phys. Rev. D49 (1994) 4694

In free space, there is a good measurement done by ALEPH group.（ ALEPH, Phys. Rep. 421(2005) 191 ）

However, identifications of Axial-Vector mesons in nucleus and high-temperature matter are difficult due to its large width.

QCD sum rule is developed to connect vector meson mass spectrum only and condensates under some assumptions

T. Hatsuda and S.H. Lee, PRC 46 (1992) R34I’m interested in measurements of vector mesons

w meson• Physics:

– Condensates in nucleus– Interplay of w-N interactions and nuclear matter effects

• Experiments– gN @ FOREST-ELPH

• Near threshold w meson photo production, R. Hashimoto et al., Few-Body Syst. (2013) 54:1135

– gA @ CB-ELSA TAPS• No mass modification (Phys. Rev. C 82 (2010) 035209)• Large width of w meson in nucleus is suggested by measurements of A-dependence

of production cross section. (Phys. Rev. Lett. 100 (2008) 192302)• Recently, they also report a depth of real part potential (Phys. Lett. B736 (2014) 26)

– Heavy Ions• As far as I know, no significant results for w mesons• HADES collaboration reports mass modification of r even in pp and AA reactions and

they study effects of N* (Phys. Rev. C84 (2011) 014902, Eur. Phys. J. A48(2012) 64)

– pA @ J-PARC• Good opportunity to study BOTH nuclear matter effects and w-N interactions,

simultaneously. 2014/10/25 K. Ozawa, Hadrons in nuclear medium 16

w in nucleus and w-N Interaction(E26)

• Measurements of w meson in nucleus using p0 g decays using an exclusive reaction

– Focus on low momentum w meson and clear mass spectrum in nucleus

– Missing mass spectroscopy and detection of an exclusive production process using the forward

• Beam Momentum is 2.0 GeV/c. – To generate w meson at rest– K1.8 or High-p


g g

gp

w p0

n

p-A + n+X

p0g

2ppm

g detector around the target

Neutron counter at the forward direction

• Detectors– High precision g detector

• DE/E = ~ 1% @ Eg = 1 GeV

– Neutron counter• DTOF ~ 80ps

2014/10/25

f meson• Physics:

– Condensates of strangeness in nucleus

• Experiments:– gA @ LEPS

• Large Width (Phys. Lett. B608 (2005) 215)

– gA @ CLAS• Large Width (Phys. Rev. Lett. 105 (2010) 112301)

– Heavy Ions• Strangeness has less absorption in high temperature matter

– For example, see Journal of Physics: Conference Series 509 (2014) 012002

– pA @ KEK-PS & J-PARC• Di-electron mass spectrum• Experimentally, only hadron beam can measure mass spectra of f mesons

clearly.


Measurements of f meson


R. Muto et al., PRL 98(2007) 042581

Indication of mass modification!

Cu

bg<1.25 (Slow)

e+e- invariant mass

Decays inside nucleusDecays outside nucleus

fmeson has mass modification

Modification is shown as an Excess

fmeson has NO mass modification

Blue line shows expected line shape including all experimental effectswo mass modification

New Goal

2014/10/25 20

Pb

Proton

A clear shifted peak needs to be identified to establish QCD-originated effects

Momentum Dependence w large statistics

E325 resultsExtrapolate


Experimental set up

2014/10/25 21

Cope with 1010 per spill beam intensity (x10)Extended acceptance (90 in vertical) (x5)Increase cross section (x2)


Construct a new beam line and new spectrometer

Deliver 1010 per spill proton beam Primary proton (30GeV) beam

New high momentum beam line

29: E f bound state?

2014/10/25 K. Ozawa, Hadrons in nuclear medium

ssuud

K+

Λ

Φ

p ud

s

us

fp -> K+L

pp -> ff

22

Mass shift of f in nucleus can produce a bound state?

Production

Detection

J. Yamagata-Sekihara, D. Cabrera, M. J. Vicednte-Vacas, S. Hirenzaki; 'Formation of Φ mesic nuclei'; Progress of Theoretical Physics 124, 147-162 (2010).

H. Ohnishi

Charm

• Physics:– Understand internal structure and interactions of “light” hadrons through Heavy

flavor hadrons

• Reactions:– (We should find a suitable reaction. Generated charm have a large momentum

due to a kinematics. Two step interactions should be considered)• DN interaction, Charmed Deuteron• Heavy Flavor in nucleus

– High Energy, High Luminosity ee collisions• Several new states are found

– Heavy Ion Collisions • Charm quarks are also thermalized in high-temperature hadronic matter. Production can

be affected by quark interactions.– Example: Lc/D0 ratio increasment, S.H. Lee et al., PRL 100 (2008)222301 – Exotic Hadrons in HI, S. Cho et al.(ExHIC Col.), PRC84(2011) 064910

– Charmed Baryon Spectroscopy • Di-quark correlation


Di-quark correlation• One of possible strong effects is a quark-quark (Di-quark)

correlationColor-Magnetic Interaction of two quarks

VCMI ～ [as/(mimj)]*(li,lj)(si,sj)

“Good Diquark”: Strong Attraction

VCMI(1S0, 3c) = 1/2*VCMI(1S0, 1c)

[qq] [ qq]

• Diquarks are emerged due to the color magnetic interaction between two quarks.

• The so-called “good diquark” has a color anti-symmetric 3bar and spin singlet configuration. It’s strong enough.

• One expects that a “good diquark” may be formed in a baryon.2014/10/25 K. Ozawa, Hadrons in nuclear medium 24

Emergent DiquarksBaryons as well as Mesons seem to be well described by a

Rotating String Configuration with a universal string tension.

“diquark”in low-lying modes


qq

qA diquark-quark picture of baryons seems valid in low-lying modesHowever, it is difficult to study strength of a di-quark correlation only using light quarks, because all combination of qq contribute and interfere.

Charmed baryon spectroscopy (E50)• Missing mass spectroscopy of excited charmed baryon using pp

-> D*X reactions to study a di-quark correlation in a baryon

K. Ozawa, 20/May/2014 26

Level structure of Charmed BaryonExperiment

Expected results

Current design of the spectrometer

Physics is approvedDetector R&D is just started.

Physics extension w the same technique• The charm baryon experiment introduces new experimental

techniques– Multi-particle measurements in the forward region– Missing mass measurements in relatively high momentum region

• K/p separation up to 10 GeV/c

– High precision measurements

2014/10/25 27

p

virtual p, K

N*, D*, Y* (slow)

high-p π r, K* (fast)

• Such new features open new experiments also in light quark .• Production of Baryon

resonance is well controlled.• Study further dependences

on momentum and reaction. K. Ozawa, Hadrons in nuclear medium

T. Ishikawa

Summary• Hadron Experimental Facility at J-PARC has following

beams

• Several experiments are on-going and planned. • Please make our facility (and related facilities) productive

as much as possible!


Name Species Energy IntensityK1.8 p±, K± < 2.0 GeV/c ~105 Hz for K+

K1.8BR p±, K± < 1.0 GeV/c ~ 104 Hz for K+

K1.1 p±, K± < 1.1 GeV/c ~ 104 Hz for K+

High-pproton 30GeV ~ 1010 Hz

Unseparated < 20GeV/c ~ 108 Hz

FUTURE UPGRADE OF THE FACILITY



+

Summary of Beam line

K10 (π,K 4 GeV/c p,pbar 10 GeV/c)HRHI (π < 2GeV/c)K1.1 (π,K,p < 1.1 GeV/c )

After Hall extractionK1.8 (π,K,p < 1.8 GeV/c)K1.8BR (π,K,p < 1.1 GeV/c)High-p ( 30 GeV proton,

< 20 GeV/c unseparated )

Existing

Physics with High-p Kaon• Ξc Spectroscopy

– Investigate Strangeness and Charm sector– K- + p -> Ξc + D- (Production Threshold: 10 GeV/c)– Use the same spectrometer with charm baryon

spectroscopy. Experimental issues, such as yield, background, resolutions, are being evaluated.

• Charmed exotic baryons– Qcs can be searched using a similar reaction.

– K- + p -> Qcs + D+


Future: Heavy Ion Beam


f in nucleus using Inverse Kinematics• Beam & Target

– 1010 ions per second 10A GeV– 40 cm H2 target ( 5% Interaction Length)

• cf. KEK-PS E325 case, 12 Gev 3 x 108 protons per sec. on 0.2 % interaction length target (Cu)

• If we assume a similar production cross section, ~1000 times larger statistics can be expected

• Production of vector meson– Maximum momentum of produced vector mesons is 9.5 GeV/c– Velocity (b) at the nuclear rest frame is 0.013

• Small enough

• Decay Measurements– Muon

• Enough momentum to identify muon due to a Lorentz boost– Acceptance is in Forward region

• 0.035 < θ < 0.14 radian, 100% particle ID• 30 % of f mesons are detected


BACK UP


New Beam Line is under construction

Construction of New Beam Line is on-going. Multi Purpose beam line for following beams

Primary Proton Beam (30GeV), 1010-12 per spillHigh Momentum un-separated secondary beam (20GeV/c), 108 per spillPrimary Proton Beam (8GeV) for COMET

PhysicsHadrons in nucleusHadron spectroscopy mu-e conversion (COMET)

2014/10/25 36K. Ozawa, Hadrons in nuclear medium

In this lecture, I will introduce new experiments using a new beam line.

KL

K1.1BR

North side

South sideH

igh

Mom

en

tum

SKS

K1.8BR


Observables


However, the quark condensate is not an observable and one need to find observables which are related to the quark condensate.

We need to find out observables related to quark condensates.Relations between mass spectra of V-AV mesons and condensates is developed using a sum rule.

Hatsuda, Koike and Lee, Nucl. Phys. B394 (1993) 221Kapusta and Shuryak, Phys. Rev. D49 (1994) 4694

In free space, there is a good measurement done by ALEPH group.（ ALEPH, Phys. Rep. 421(2005) 191 ） See the next slide.

Condensates and spectra


ALEPH, Phys. Rep. 421(2005) 191

QCD Sum rule


q

q

Vacuum Vacuum

QCD sum rule

Average of Imaginary part of P(w2)

vector meson spectral function

T.Hatsuda and S.H. Lee,PRC 46 (1992) R34

03.0;10

*

B

V

V

m

m

Prediction

Spectrum

mV

Theoretical Assumption

Example:

Measurements of axial vector mesons in a medium is difficult.Different type of sum rule is proposed.

Measurements of vector mesons can be done in nucleus and high energy collisions.

Current status of experiments

• High energy heavy ion collisions– SPS-NA60 (PRL 96 (2006) 162302)

• Modification of r meson due to hadronic effects– RHIC-PHENIX (PRC81(2010) 034911)

• Origin of the enhancement is under discussion

• Nuclear targets– CBELSA/TAPS (Phys.Rev. C82 (2010) 035209)

• Modification of w is not observed– J-LAB CLAS G7 (PRL 99 (2007) 262302)

• Mass broadening of r due to hadronic effects– KEK-PS E325 (PRL 96 (2006) 092301)

• Peak shift and width broadening of /r w

2014/10/25 41

Most measurements are done for /r w mesons

Large uncertainty in background subtraction method


Several hadronic and experimental effects cause difficulties in /r w measurements.

How about f meson?• /r w

– Dynamical mass contribution is dominantMp ~ 130 MeV/c2 Mr ~ 770 MeV/c2

– Large hadronic effects and background issues are large• f

– Still, dynamical mass contribution is dominantMh ~ 550 MeV/c2 Mf ~ 1020 MeV/c2

– Narrow width ( 4.3 MeV/c2)• Small background issue

– Small effects of hadron-hadron interactions• e.g. Binding energy of fN is 1.8 MeV (Phys. Rev. C 63(2001) 022201R)

2014/10/25 42

To see QCD-originated effects, f meson is the most promising probe.


KEK-PS E325 Experiment• Finite density matter• Stable system• Saturated density

Measure Vector meson spectrum


Use Nucleus

Generate vector mesons using proton beamMeson mass spectrum in nucleus can be measured using decays and compared to the prediction.Leptonic (e+e-) decay is suitable, since

lepton doesn’t have final state interaction.

T.Hatsuda and S. Lee,PRC 46 (1992) R34

03.0;10

*

B

V

V

m

m

Prediction

Experimental Setup


12 GeV proton induced. p+A f + X

Electrons from f decays are detected.

KEK E325

E325 Spectrometer



Target/Momentum dep.bg<1.25 (Slow) 1.25<bg<1.75

Only one momentum bin shows a mass modification under the current statistics.

To see clear mass modification, significantly larger statistics are required.

e+e- invariant mass

Two nuclear targets:Carbon & CopperInside-decay increases in large nucleus

Momentum binSlowly moving f mesons have larger chance to decay inside nucleus

Same as previous slide

Excess

What can be achieved?


Pb

fModified f

[GeV/c2]

f from Proton

Invariant mass in medium

ff

ff

ff

ff

p dep.

High resolution

Dispersion relation

Next step


Then, calculate quark condensate using QCD sum rule.

Experimental requirements

1. High statics2. Good mass resolution

Average of Imaginary part of P(w2)

Assumed Spectrum

Evaluate quark condensate directly.

Replace by average of measured spectra

p

Detector components


Tracker~Position resolution 100μmHigh Rate(5kHz/mm2)Small radiation length(~0.1% per 1 chamber)

Electron identificationLarge acceptanceHigh pion rejection @ 90% e-eff.

100 @ Gas Cherenkov25 @ EMCal

R&D Items


Develop 1 detector unit and make 26 units.① GEM foil

③ Hadron Blind detectorGas Cherenkov for electron-ID

② GEM Tracker

Ionization (Drift gap)+ Multiplication (GEM)

High rate capability + 2D strip readout

CsI + GEMphoto-cathode

50cm gas(CF4) radiator~ 32 p.e. expected

CF4 also for multiplication in GEM

Beam test results of prototype detectors (2012)

100x100 200x200 300x300

10 p.e.

QE upto 40%

Required position

resolution (~100m) is

achieved

UV Cherenkov

photons are

detected with

CsI-evaporated

LCP-GEM

and CF4 gas

● Large size (300x300mm) PI- and LCP-GEM are successfully worked for a electron beam– Stability and response for a pion beam should be checked at J-PARC.

● GEM Tracker is successfully worked. ● Improvement of the photo-detection efficiency of HBD is on going.

GEM Tracker

HBD (Hadron-Blind Cherenkov detector )


GEM Tracker : first prod. type is testedislands for Y-strip(Ni plated)

X-strip(Ni plated)

Y-strip

200mm

125mm

x

Y

island

100mm

Y.Komatsu, NIM A 732(2013)241

BVH type 2D R/O PCB2014/10/25 K. Ozawa, Hadrons in nuclear medium 52

53

HBD @ J-PARC

2014/10/25 K. Ozawa, Hadrons in nuclear mediumCerenkov blob, f ~34mm

Electron

HBD (Hadron Blind Detector) ● Test @ J-PARC K1.1BR in 2013/Jan (T47)

● pion rejection is improved with a higher gain of new PI-GEM and smaller-size readout pad

– measure the distributed charge: selecting 3 fired pads or more• → pion rejection factor 100 with e-efficiency 70% achieved, same level as

PHENIX, in spite of the less #p.e.

e-eff. 70%

rejection>100


Emergent DiquarksBaryons as well as Mesons seem to be well described by a

Rotating String Configuration with a universal string tension.

M2~ *W LA distance of [qq]-q/ q-q increases as L increases.

q

q


qq

q

L L

Emergent Diquarks

0 1 2 3 4 5 6 70

1

2

3

4

5

6

7

8

9

10

NDeltaLambdaSigmaXi

0 1 2 3 4 5 6 70

1

2

3

4

5

6

7

8

9

10

rho/aomega/fphi/fK*

Baryons Mesons

LL

M2 (

GeV

2 ) M2 1.1∝ L M2 1.1∝ L

Baryons as well as Mesons seem to be well described by a Rotating String Configuration with a universal string tension.

2014/10/25 56K. Ozawa, Hadrons in nuclear medium

Experiment• Observable is a production cross section of vector meson as a

function of t.• Charmed baryon spectrometer will be used also for this

experiment. There is enough acceptance. Missing mass resolution of 10 MeV/c2 can be achieved.


Measurements of K* production are also under discussions to investigate strange

quark sector.

By T. Ishikawa

Muon decays of f mesons• Simple calculation for the easiest

case– f mesons are produced in the beam

direction with a momentum of 9.5 GeV/c

– f mesons are decayed into muon pairs isotropically at the f rest frame

• Momentum and emitted angle of muons are calculated– Momentum distribution is almost

flat • Large fraction has enough momentum

– Muons are generated in the forward region

• Acceptance is calculated– 0.035 < θ < 0.14 radian, 100%

particle ID– 30 % of f mesons are detected


Momentum distribution of muons from f decays

50 10 [GeV/c]

A.U

.

0.50 1 [rad]

A.U

.

Angle distribution of muons from f decays

future of hadron physics experiments at j-parc k. ozawa (kek) contents: j-parc & hadron facility...

Documents

constituent of hadron

jparc hadron facility

aspects of hadron physics

hadron qcd medium

hadron properties interaction

inside structures of

hadron transfer line

nuclear medium slide