1. Hadron experimental facility at J-PARC
K. Ozawa (KEK)

2. J-PARC (Japan Proton Accelerator Research Complex)
Tokai, Japan
50 (30) GeV Synchrotron (15 mA)
Material and Biological Science Facility
Hadron Hall
60m x 56m
3 GeV Synchrotron (333 mA)
400 MeV Linac (350m)
Neutrino Facility
World-highest beam intensity : ~1 MW
x10 of BNL-AGS, x100 of KEK-PS
2014/03/07
K. Ozawa

3. Nuclear & Hadron Physics at J-PARC
L,X N Z
L, S Hypernuclei
LL, X Hypernuclei
Strangeness
Hypernuclei -1 -2 d u s
Pentaquark +
He 6
K1.8 KL
K1.1BR
High p (not yet)
SKS
K1.8BR
K1.1
Implantation of
Kaon and the
nuclear shrinkage
K meson
Free quarks
Bound
quarks
Why are bound quarks haevier？
Quark
Mass without Mass Puzzle
On the other hand, the hadron experimental hall looks like this.
● Proton beam comes here and various kaon beam lines are prepared, where K=1.8 means kaons with momentum of 1.8 GeV/c.
● At SKS, hypernuclear spectroscopy will be performed for a variety of nuclei. ● In particular, searches for double hypernucleus and pentaquark are the highlights in here.
● In this beamline, kaon implantation is planned. When kaon is implanted inside the nucleus, there is a possibility that high density matter is created. ● Kaonic atom and kaonic nucleus will be studied.
● This beam line is the neutral kaon line to study CP violation, and ● this line is for T-violation experiment.
● Finally, this line, which is not yet completed, is dedicated to the study of chiral symmetry, namely, the mass generation mechanism of bound quarks.
Kaonic nucleus
Kaonic atom
Ｘray Ｋ−
Proton Beam
2014/03/07
K. Ozawa 3

4. Summary of existing beam lines
K1.8 KL
K1.1BR
High p (not yet)
SKS
K1.8BR
K1.1(not yet)
Name
Species
Max. Mom.
Max. Intensity
K1.8
p, K, p (2 separators)
< 2.0 GeV/c
~105 Hz for K+
K1.8BR
p, K, p (1 separator)
< 1.0 GeV/c
~104 Hz for K+
K1.1BR
< 1.1 GeV/c KL
Neural Kaon
~ 2 GeV/c
~106 Hz
2014/03/07
K. Ozawa

5. South side North side KL SKS High Momentum K1.8BR K1.1BR 2014/03/07
絵の説明
2014/03/07
K. Ozawa 5

6. SKS Spectrometer K1.8 Beam Spectrometer Q13 Q12 D4 Q11 Q10 2014/03/07
実験エリアの現状　2009年秋からビームタイム開始 D4
Q11
Q10
2014/03/07
K. Ozawa 6

7. Physics Program @ J-PARC
Hadron-Hadron interaction
Strangeness Nuclear Physics
Hyperon-Nucleon interaction
Meson-Nucleon interaction
Hadron in Nuclear Medium
Chiral symmetry and hadron mass origin
Internal structure of Hadron
Exotic baryon (Penta Quark, H di-baryon)
Di-quark correlations
Hadron form factors
I will pick up few examples. (Not cover all experiments. )
and introduce a new beam line.
2014/03/07
K. Ozawa

8. E19:Penta quark - results
2010 data
Search for the Θ+ via the p+π-→K-+X　Reaction at 1.97GeV/c
No peak of Q+ was observed.
U.L. (90%CL) 0.26mb/sr (2-14°) in GeV/c2
U.L.(90%CL) of GQ
0.72 MeV (1/2+)
3.1 MeV (1/2-)
PRL 109 (2012)
The first published (physics) paper from J-PARC Hadron.
2014/03/07
K. Ozawa

9. Experiment using Kaon beam
Example…
More experimental information on LN, XN, LL, SN interactions are awaited.
Several related experiments are under preparation at J-PARC.
Baryon fraction in neutron star
g spectroscopy for light hyper nuclear using (K-, p-) reaction at pK=1.5 (or 1.1) GeV/c.
Schaffner-Bielich, NP A804 (2008).
Important Input from experiments.
UL = - 28 MeV (c.f. UN = -50 MeV)
Determined by Hypernucleus experiment
at KEK-PS
2014/03/07
K. Ozawa

10. New Beam Line
Construction of New Beam Line is proposed as a high priority plan of the lab.
Characteristics of the beam line is following.
Primary Proton Beam (30GeV), per spill
High Momentum un-separated secondary beam (< 20GeV/c), 108 per spill
Primary Proton Beam (8GeV) for COMET
Basic Design of the beam line is done.
Beam line components are under construction
Physics
Vector mesons in nucleus
Charmed Baryon and hadron structure
mu-e conversion (COMET)
2014/03/07
K. Ozawa

11. Experiment @ new beam line
Hadron Mass as excitation levels of “vacuum”
In light quarks (u, d, s) sector, hadron mass consists of Bare mass (Higgs) and Dynamical mass (QCD).
Dynamical mass part is strongly related to a surrounded medium and reliable experimental information in a different medium is important.
Vector mesons (r, w, f meson) are used as probes.
Mass spectra of vector mesons can connect to qq condensates
e.g. Hatsuda and Lee, PRC 46 (1992) R34
Use leptonic (electron) decays to avoid the final state interaction
Mass [GeV]
Obtain constituent quak mass
Pseudo scalar meson as a NG boson （Jp=0-）
2014/03/07
K. Ozawa

12. Measurements of f meson at KEK-PS.
The only one measurement on medium modification of f meson.
R. Muto et al., PRL 98(2007) Cu
bg<1.25 (Slow)
e+e- invariant mass
Decays outside nucleus
Decays inside nucleus
meson has NO mass modification
Blue line shows expected line shape including all experimental effects
wo mass modification
meson has mass modification
Modification is shown as an Excess
Indication of mass modification!
2013/2/11
J-PARC Future 2013, K. Ozawa

13. Next Goal @ J-PARC Pb 100 times larger statistics will be collected.
A clear shifted peak needs to be identified to establish QCD-originated effects
Momentum Dependence Pb
E325 results
Extrapolate
Proton
100 times larger statistics will be collected.
2013/2/11
J-PARC Future 2013, K. Ozawa

14. High momentum secondary beam
The same beam line will be used as a high momentum secondary beam line which delivers un-separated secondary beam.
Main component is p mesons
K mesons and protons are also contained
Phsyics
Charmed baryon spectroscopy
pN exclusive di-lepton production related to a structure function
2014/03/07
K. Ozawa

15. Key components
High resolution of the beam momentum measurements using a dispersive focal plane method.
Dp/p ~ 0.12%
Spectrometer
Small extraction angle to maximize a beam intensity.
2014/03/07
K. Ozawa

16. Production target & extraction
Using beam swingers, extraction angle of 0 degree can be achieved.
2014/03/07
K. Ozawa

17. Secondary beam intensity
2014/03/07
K. Ozawa

18. Experiment: Heavy quark baryon
l: orbital motion
r: di-quark correlation
When single quark picture is still a good picture, excited states are degenerated.
If Cqq (q=u,d) system is considered as C and di-quark correlations, orbital motion of l is lowered due to the collectivity of the di-quark motion.
Spin correlations between light quarks give additional level separations.
Level pattern tell us:
Mass of di-quark
Strength of di-quark correlation
Spin dependent correlation between light quarks
2013/2/11
J-PARC Future 2013, K. Ozawa
Measurements of all levels are important

19. Missing mass Spectroscopy
2.3 Tm Dipole K+ DC
PID
Use forward D mesons production
No Bias measurements up to 3GeV/c2 of Charmed Baryon mass
H2 TGT
PID
Beam p-
High rate Trackers
(Fiber, SSD) DC p-
TOF p-
LAMPS
Large Acceptance, Multi-Particle
K, p from D0 decays
Soft p from D*- decays
(Decay products from Yc*)
High Resolution
High Rate
SFT/SSD op. >10M/spill at K1.8
2013/2/11
J-PARC Future 2013, K. Ozawa

20. Summary Hadron experimental hall has following beam lines.
K1.8, K1.8BR, K1.1BR, KL
A new beam line for a primary proton beam is under construction
In future, a high momentum secondary beam using the newly constructed beam line is under consideration.
2014/03/07
K. Ozawa

21. 2014/03/07
K. Ozawa

22. Back up
2014/03/07
K. Ozawa

23. High-p/COMET beam line
Steel-septum (Lambertson) magnet,
Current-septum magnets x2
New Beamline magnets
Dx7, Qx8
Collimators
(H, V)
3 of existing beamline magnets
(Dx1, Qx2) are replaced to avoid interference with new line
Most of beamline magnets
(D:7/7, Q:6/8) are reused ones
Existing steering magnets (x2) to make a bump orbit vertically for beam extraction to high-p/COMET
2014/03/07
K. Ozawa

24. High-p/COMET beam line
Beam plugs
High-p beamline magnets
Dx5, Qx3
Spectrometer Magnet
Beam plugs
high-p
beam dump
COMET beamline magnets
Dx5, Qx4
COMET
beam dump
Capture Solenoid
Most of beamline magnets
(D:8/10, Q:5/7) are reused ones
2014/03/07
K. Ozawa

25. K- beam @ K1.8 K rate : 320k /spill (K/all=71%)
MR power : 20 kW ( 2.51013 ppp )
ESS voltage :  250 kV
1.5 GeV/c
1.8 GeV/c K- K-
Black : all events
Green : BAC
π-,μ-,e-
π-,μ-,e-
IFY=+2.7/-1.1mm, MS1/MS2=±1.7mm
IFY=+1.8/-0.2mm, MS1/MS2=±0.9mm
K rate : 320k /spill (K/all=71%)
K rate : 290k /spill (K/all=75%)
We can start nuclear/particle physics using Kaon beam.
2014/03/07
K. Ozawa