H Sako ASRCJPARC JAEA for JPARC HeavyIon Collaboration TGSW2016 Session 6 Universe Evolution and Matter Origin Tsukuba 2016921 Outline Introduction HI acceleration ID: 547387
Download Presentation The PPT/PDF document "J-PARC Heavy-Ion Program (J-PARC-HI)" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
J-PARC Heavy-Ion Program (J-PARC-HI)
H.
Sako (ASRC/J-PARC, JAEA) for J-PARC Heavy-Ion CollaborationTGSW2016 Session 6 "Universe Evolution and Matter Origin” Tsukuba, 2016/9/21
OutlineIntroductionHI accelerationPhysics goalsExperimental designSummary and prospect
1Slide2
J-PARC-HI Collaboration
88 members : Experimental and
Theoretical Nuclear Physicists and
Accelerator Physicists ExperimentH. Sako, S. Nagamiya, K. Imai, K. Nishio, S. Sato, S. Hasegawa, K. Tanida, S. H. Hwang, H. Sugimura, Y. Ichikawa K. Ozawa, K. H. Tanaka, S. Sawada, M. Chu, G. David, T. Sakaguchi, K. Shigaki, A.
Sakaguchi, T. Chujo, S. Esumi, Y. Miake, O. Busch, T. Nonaka, B. C. Kim, H. Masui, K. Sato, M. Inaba, T. Gunji, H. Tamura, M. Kaneta, K. Oyama
, Y. Tanaka, H.
Hamagaki
, M. Naruki,S. Yokkaichi, T. Hachiya, T. R. Saito, X. Luo, N. Xu, B. S. Hong, J. K. Ahn, E. J. Kim, I. K. Yoo,M. Shimomura, T. Nakamura, S. Shimansky, J. Milosevic, M. Djordjevic, L. Nadjdjerdj, D. Devetak, M. Stojanovic, P. Cirkovic, T. Csorgo, P. Garg, D. MishraTheoryM. Kitazawa, T. Maruyama, M. Oka, K. Itakura, Y. Nara, T. Hatsuda, C. Nonaka, T. Hirano,K. Murase, K. Fukushima, H. Fujii, A. Ohnishi, K. Morita, A. Nakamura, Y. AkamatsuAcceleratorH. Harada, P. K. Saha, M. Kinsho, Y. Liu, J. Tamura, M. Yoshii, M. Okamura, A. KovalenkoASRC/JAEA, J-PARC/JAEA, J-PARC/KEK, Tokyo Inst. Tech, Hiroshima U, Osaka U, U Tsukuba, Tsukuba U Tech, CNS, U Tokyo, Tohoku U, Nagasaki IAS, Kyoto U, RIKEN, Akita International U, Nagoya U, Sophia U, U Tokyo, YITP/Kyoto U, Nara Women’s U, KEK, BNL, Mainz U, GSI Central China Normal U, Korea U, Chonbuk National U, Pusan National U, JINR, U Belgrade, Wigner RCP, KRF, Stony Brook U, Bhaba Atomic Research Centre, Far Eastern Federal U
2Slide3
Goals of J-PARC HI Project
-physics of extremely dense matter-
RHIC/LHC discovered QGP at high T and low
rHowever, no direct evidence for the critical point and phase boundaries discovered. At J-PARC, the highest density matter in the lab can be created.5-10 r
0 ~ neutron star coreGoals at J-PARCStudies of phase structuresHadron/nuclear properties at high density Utilizing world’s highest intensity HI beams
3
LHC
RHIC
GSI-SIS
m
B
J
-PARC
Location unknown theoreticallySlide4
4
NICA (collider)
CBM
FAIR SIS-100
RHIC BES II
NN
NICA
(fixed target)
Highest baryon density
HI experiments for high density physics
Aiming at world’s highest
Beam rate
of 10
11
Hz
Interaction r
ate
1
0
8
Hz
Note
: experimental limitation not considered(2019-2020)
(2022-)
(2020-)
J-PARC
(2017-)
SIS-100 beam rate
：
~5x
10
9
Hz
Ion species
p, …, Au, U
Beam energy
1-
19 A GeV
Extremely important as accelerator science
Collision energy √S [GeV]
Interaction rate [Hz]Slide5
HI accelerator scheme
RCS
(H
- p)0.4 3 GeVMR330 GeV (p)H-
Linac: 0.4 GeV
MLF
p to NU proton (existing)p to HDU86+62 735 AMeVstripping
U
92+
0.73
11.2
AGeV
p/
HI
to HD
HI (under plan)Figures: Not to scaleHI boosterU
35+→U66+20 67 AMeV
stripping
stripping
HI
Linac
U
35+
20
AMeV
5
400MeV p
Parallel
oper
HI(MR)
p
(MLF)
50m
Booster
Linac
50mSlide6
Observables for QCD phase structures
DileptonsPenetrating probes of dense matterModification of
r/w/f linked to chiral symmetry restorationHadron measurements (high statistics)
Event-by-event fluctuationsCollective flow (searching for 1st order transition)CharmJ/y, D,…Sensitive to initial dense matter? Photons (real and virtual)Thermal radiations from QGP6Slide7
Approaching to even higher density
In addition to centrality, event selection with large strangeness and net baryon numberu
tilizing extremely high statistics at J-PARC
7A. Ohnishi,J. Phys. Conf. Ser. 668 (2016) 012004
J. RandrupPRC82 (2010) 034902Critical pointMixed phase
Unstable
region
Beam-energy scan(no event selection)
Baryon-rich events
High
m
region can be studied
by selecting baryon rich eventsSlide8
Net-proton fluctuations
8X. Luo, Quark Matter 2015
M.A.
Stephanov,PRL107, 052301 (2011).
J-PARCTheoryEbe fluctuations : Probe to search for the critical pointw/ higher-order fluctuationsEnhancement of 4th-order fluctuations at low energies Indications of the critical point?Slide9
NA60
In+In, 158AGeV/cHADES Ar+KCl
1.76AGeV/cCERES Pb+Au
40AGeV/cCERES Pb+Au 158AGeV/c CERES S+Au 200 AGeVPHENIX Au+Au 200 AGeV MB (Phys. Rev. C 93, 014904)
STAR Au+AuLow-mass dileptonsMaximum low mass enhancement aroundJ-PARC energies?Dielectrong conversion at low mass (background)Dimuon
p
,K
m decay (background)Higher rate beam can be usedHigh statistics at J-PARCMoment analysisDirect comparison to theoretial models (e.g. QCD sum rules, related to quark and gluon condensate) Hayano and Hatsuda, RMP82, 29499J-PARC●NA60 In+In, 158AGeV/cHADES Ar+KCl 1.76AGeV/cCERES Pb+Au 40AGeV/cCERES Pb+Au 158AGeV/c CERES S+Au 200 AGeVPHENIX Au+Au 200 AGeV (PRC81,034911(2010))STAR Au+AuHighest baryon density 5-8GeV? (J. Randrup, PRC74(2006)047901)
T.
Galatyuk
,
EM probes
of
Strongly Interacting
Matter
ECT
*, Trento
2007
(PHENIX data updated)
Baryon density
J.
Randrup
, PRC
74
047901
(2006)
Low-mass
dilepton
enhancement factor
Measured / cocktail in m=0.2-0.8
GeV
/c
2
Slide10
|
S|>=3 hypernuclei
Extension of Hadron nuclear physics to high density with HI collisions
10HI experiment
Neutron StarChiral restorationdilepton in A+AChiral restoration dilepton in p+A
(E16)
Meson beam experiments
YN YY interactionsNeutron star densityEOSExotic hadronsPentaquark (E19)H-dibaryon (E42)Exotic hadrons(distinguish structure by production yield)Hypernuclei|S|<=2 (E10,E13)Normal nuclear density太陽質量の２倍⇒硬いEOSＹ,Ｎ三体力?Quark-hadron phase transition?Kaonic nuclei：K-pp(E15, E27)中性子過剰ハイパー核中性ハイパー核: nnL, nnLL
L
*
Cluster
Strangelet
(strange quark matter)
Collective
f
low
2-particle correlation (HBT)Slide11
Particle production rates
11
Beam
: 1010 Hz0.1 % target Min-bias event rate 107HzIn 1 month experiment:r,w,fee 109
-1011Hypernuclei 103 -1011HSD calculations in FAIR Baseline Technical Report (Mar 2006)A. Andronic, PLB697 (2011) 203
Dilepton
Hypernuclei
AGSStrangelets: P. Braun-Munzinger J.Phys.G21 (1995)L17Y, pt spectraEvent selectionsMeasurementsand Search10-13 sensitivity at J-PARCSlide12
Experimental challenges
High rate capabilityFast detectorsSilicon trackers, GEM trackers, …Extremely fast DAQMin-bias event rate = 10MHz
Triggerless
DAQ Large acceptance (~4p)Coverage for low beam energies Maximum multiplicity for e-b-e fluctuationsElectron measurementField free region for RICH near the target Toroidal magnet spectrometer12
(CBM<30o, beam energy>=8AGeV/c)Slide13
3.2
m
Neutron counter
EMCAL
ZCAL
Beam
RICH
4
m
Muon
Tracker
R=1
m
Top
View
13
Toroid
coils
0.25
m
0.5
m
1.4
m
0.65
m
1.90m
TOF
SVD
ZCAL
4.4m
Centrality
MC
+ ZCAL
Multiplicity
counter
C
5
F
12
radiator
p<3.4GeV/c
e-
p
separation
EMCAL (
e,
g
ID)
PbWO
4,
15X
0
JHITS
m
–
p
separation
Fe absorbers
+trackers
GEM trackers
Neutron detectorSlide14
Hypernuclear spectrometer (JHYPER)
14
H. Tamura,
Remei Workshop, 10 Aug 2016, Tokai, Japan
At 10
7
Hz interaction rate
Track rate in TPC : 9.3x106 HzTrigger rate : 4.0x103 HzExperiment with full beam rate may be feasible!Slide15
Summary and Prospect
15
Rich physics for high density matter in HI collisions
Acceleration at 4x1011/cycle by adding
a linac and a booster to RCS and MRLarge acceptance toroidal spectrometer for lepton/hadron measurementsHypernuclear spectrometer utilizing full beam intensityProspectsAccelerator R&D of ion source, linac, and boosterDetector R&D with the high-p beamline experiments at J-PARC (E16, E50) and heavy-ion experimentalistsMRPC-TOF (Tsukuba, JAEA, KEK) in J-PARC E16 (p+A) DAQ (JAEA, Nagasaki IAS), Collaboration with ALICE Online-Offline Computing (O2)
W
hite paper completed in June
2016 (http://asrc.jaea.go.jp/soshiki/gr/hadron/jparc-hi/index.html)LOI submitted to J-PARC PAC in Jul 2016Discussions in J-PARC and in nuclear physics community are going on Goal : Start earliest in 2025Slide16
backup
16Slide17
Hypernuclear
spectrometer
Search for|S|>=3
HypernucleiStrangeletHypernuclear production at ybeam Life time Magnetic moment17
12C Target12C BeamCollimator (W)
1
m
Dipole magnet0.5mPrecession magnet TOFChargecounterZCAL1.5mBdL = 6Tm Precession angle ~ 68o (assuming mL
)
1
m
Trigger counter
for
decay
p
-
TPC
hypernucleus
p
-
nucleus
Fragment separation at TPC
Ideas b
ased on
M.
Asakawa
et al, KEK Report 2000-11
T. R. Saito et al,
HypHI
Letter of Intent, 2005
Beam
bg
c
t
(
L
) ~
1.6m
Total
BdL
= 6Tm
Precession angle ~ 68
o
(assuming
m
L
)
JHIPER
Horizontal
positions at
TPC
All particles
At 10
7
Hz interaction rate
Track rate in TPC :
9.3x10
6
Hz
Trigger rate :
4.0x10
3
Hz
Experiment with full beam rate may be feasible!
PRC54
, R15 (1996)
PRC76
011901(R
)
(2007)
3
He
p
-
3
L
H
3
He
+
p
-
C+C at 15
AGeV
/c
JAM-1.622 (RQMD/S mode)
+ GEANT4
Y. Nara, et al
, Phys. Rev. C61,024901(1999)
M.
Isse
, et al,
Phys.Rev
. C72 (2005) 064908
Side
Top
viewSlide18
Hyperon c
orrelation in HI collisions (STAR)
18
STAR, PRL114 (2015) 022301
(Morita et alPRC91 (2015) 024916)
Search for H-
dibaryon
and study of baryon-baryon interactions from LL momentum correlationXN, WN correlation also possibleX- and W multiplicities = 0.6/0.03 at 10 AGeVWp : K. Morita et al, Phys.Rev. C94 (2016) 031901LL correlation functionQS+BB interactionNagaraSTARSTARSlide19
Advantage of J-PARC HIC program:
high-luminosity/statistics Example: event selection by
①
Net-baryon number② Total-strange numbervarious event selections
Beam-energy scan
(no event selection)
Baryon-rich events
average transverse energy High m region can be studied by selecting baryon rich events
faster
increase
non-monotonic
behavior
as evidence of 1st.
tr
?
Baryon-rich
events
19
Courtesy of M. Kitazawa
Event selectionSlide20
Possible HI spectrometer location
20
High-p beam line
High-p beam lineSpace for HI spectrometerRadiation shieldSlide21
Search for strangelet at AGS-E886
~10-7 sensitivity (~ ybeam)
21
PID of fragments is done with TOF and Z measurements
TOFA. Rusek, PRC54 R15
Search region
dE
/dx vs brelationp=1.8GeV/cJ-PARC20mAGS D6 Beamline (30m)Z=1Z=2Z=3Z=4HI beamHadrons/nucleiDESlide22
Beam
View
RICH
Muon
Tracker
22
Neutron counter
EM
CAL
Toroid coils
12-fold coils
B
f
v
ariations ~+-20%
Coils = insensitive
area
JHITS
J-PARC Heavy Ion
Toroidal SpectrometerSlide23
Distinguishing exotic hadron structures in HIC
S. Cho et al (ExHIC collab), PRC84 (2011) 064910
23
Yields depend on the system size assuming a quark coalescence model (at RHIC or LHC)Application to J-PARC?e.g. L(1405) is KbarN or 5-quark state? Slide24
24Slide25
25Slide26
26Slide27
AGS D6 beamline
27Slide28
EOS from collective flow
To measure EOS is one of the ultimate goals of nuclear experimentsFlow as a function of sqrt(s) may have important information of EOSDanielewicz et al., Science 298 (2002) 1592
28Slide29
Spectrometer performance
Acceptance >= 78 %p/K separation 2.5GeV/c (2.5
s)
Assuming TOF resolution of 50 ps29Forward trackers Acceptance = 77.5
%Acceptance = 64.2%Acceptance = 95.0%Dp/p
p
(GeV/c)
U+U at 10AGeV/c with JAM + GEANT4Assumption for simplicity Half-spherical toroidal shapeUniform Bf fieldNo dead area due to coilsH. Sako, B.C. Kimp+pyym2 (GeV/c2)p/Z (GeV/c)Slide30
Reconstructed
dilepton
spectra
heegh’ee
greewee
f
ee
p0eegm+m- cocktail (500 M events)No K,p weak decaysqee>5o2o<q<80opT>0.1 GeV/cVery PreliminaryGeneratedReconstructedLike-sign pairsLike-sign mixedSignalDielectrons
30
Very Preliminary
q
ee
>2
o
2
o
<
q
<80op
T>0.1GeV/cDimuonsB/S~23(CERES)B/S~4(J-PARC)wp0eehmmgh’
mmg
r
mm
w
mm
f
mm
w
p
0
mm
e
+
e
-
cocktail (8.6 M events)
No
g
external conversionSlide31
Comments on S=-3 nuclei
Smallest triple L nuclei will be 14CLLL
, since 3rd
L should be in p-shell which is only bound larger than A=11 (13CL) .Possible smaller s=-4 nuclei can be; 4He+LL+X0 system ~10-7
A. J.
Baltz
,
C. B. Dover et al, PLB325 (1994) 7Slide32
Dileptons at J-PARC energy
Penetrating probes of dense matterLow Mass Rangein-medium modification of vector mesons (link to chiral symmetry restoration)
Intermediate Mass RangeDD is suppressed
Sensitive to QGP thermal radiation?32Axel Drees
T. Sakaguchi, JHI2014Talk by T. Hatsuda (20th)Slide33
PBM’s Thermal model
33Slide34
34Slide35
ZCAL
Beam
Muon
Tracker
Top View
35
0.5
m1.2mGEM trackers1.4m
Dimuon
trigger
A positive and a negative particles after
7
l
absorbers
At the interaction rate of 10MHz
Dimuon trigger rate (background)
=3x104 Dimuon trigger rate (signal)
~104(forward muon tracker (
q<33o))Experiment with full beam rate may be feasible!SVD
0.4 m
Pb
absorbers
Dimuon
specialized spectrometer (preliminary)
0.4
m
0.5
m
Dipole
Magnetic
field
Fe
absorbersSlide36
Hadron physics in HI collisions
Two particle correlationsYN, YY correlations in high baryon densityCollective flow
(related to EOS?)Exotic hadrons
L(1405), pentaquarksDibaryons (H-dibaryon, WN, DD,…)Kaonic nucleus (K-pp,…)Hadron structures distinguished with production yields compared to quark/hadron coalescence mechanisms? S. Cho et al (ExHIC Collaboration) PRC 84, 064910Hypernuclei
36J-PARC experiments with p/K beamsJ-PARC E16 p+ASlide37
37Slide38
Pictures of
h
eavy-ion collisions
Lower energy
(J-PARC)
P
beam
= 10-20 AGeV/c
Nuclei stop
Nucleons pile up
High energy (LHC/RHIC)
Center of mass energy >=200
AGeV
Nuclei
penetrate
each other
Quark-gluon plasma
3/30/2012
38
Hadron seminar @J-PARC
K.
Itakura
, T.
Sakaguchi
Very hot and low density matter
Hot and dense matterSlide39
QCD sum rule and spectral function
39http://macdls.lbl.gov/DLS_WWW_Files/DLSWorkshop/proceedings.html
Comment by Tetsuo Hatsuda
International Conference on Soft Dilepton ProductionLBNL, 1997See also, Hatsuda, Hayano, RMP82, 2949 スペクトル自身よりも、積分値の方がより直接的に実験と
QCD凝縮を比較できるWith integrated values (moments), QCD condensates can be compared to the experimental data more directly than with the spectral function itself.Courtesy of M. KitazawaSlide40
JAM RQMD/S mode (v1.622)
Inelastic hadron-hadron collisions are modeled by the resonance and string productions and their decays (similar to the RQMD and UrQMD models). Nuclear mean field is simulated based on the framework of the simplified version of relativistic Quantum Molecular Dynamics.
40Slide41
g
external conversionMaterial budget from the target to photon L/X0 ~ 4.32%
Np0 = 240
e+ and e- from g conversion~Np0 * L/X0 * 2 = 21 / event 41detectorR(cm)thickness
MaterialL/X0Target(0.1%)00.051mmAu(1/2) (0.508mm)
1.52%
SVD
7.50.3mmSi(0.2mm)+polyimide1.24%GEM Photon detector1800.025mm0.100mm0.027mmKapton(286mm)Mylar(285mm)Cu(14.35mm)G-10 (1.5mm)1.52%4.32%Slide42
Muon weak decay
Muon multiplicity (U+U 10AGeV/c, JAM)Nm+(p>1.5GeV/c)=2.07Nm-(p>1.5GeV/c)=2.41N(
m++m
-) = 4.48Weak decay rejection by track matching~ 80%The expected muon weak decay contamination4.48*(1-0.8) = 0.89 / event42Slide43
Muon ID performance
43
p
+ survival probability~2x10-3~70%
Track matching before and after the first absorberm+ efficiencyp(GeV/c)p(GeV/c)D
y
(mm)
Dx(mm)low p cut-off~1.5GeV/c6lint absorberSlide44
44
KenIchi
Imai
,
J-PARC
HI meeting (2013/4/24)Slide45
Hypernuclear physics with HI
GoalsDiscovery of new hypernuclei and extension of hypernuclear chart
S=-1,-2,-3 hypernucleiProton-rich and Neutron-rich hypernuclei
Can be done in mid-rapidity or beam/target rapidityIdentification with weak decay to a (light) nucleus + p-Study of weak decays at beam rapidityWith meson beams, due to short decay length these measurements are difficultlife time measurementMesonic decay e.g. 4ΛH→ π−+4He (4He ground state) standard way to identify a hypernucleusNon-mesonic weak decayΛp →
pn (p,n : high momentum) the rest nucleus is exited state, and will break.Measurements of residuesMagnetic moment Never measured!Sensitive to hyperon wave function inside hypernucleusSpin and angular momentum structureSpin-dependent YN interaction 45Slide46
Strange meson/baryons
Systematic energy scan below the “horn” at ~8 GeV
There is almost no
X, W measurements46
A. Andronic et al, Nucl. Phys. A 837 (2010) 65J-PARCSlide47
Hypernuclei
Maximum yield at J-PARCCoalescence of high-density baryonsS=-3 HypernucleiPrecise secondary vertex reconstruction (mid rapidity)
47
A. Andronic, PLB697 (2011) 203 J-PARCSlide48
Kaonic nuclei production in HIC
Andronic, PBM, et al, NPA 765 (2006) 211–225Evidence of K-
pp state at J-PARC (E27) (p++d K
++K-pp), but no other states yetStatistical thermal model calculationMaximum yields at J-PARC energy range48
J-PARCJ-PARCSlide49
49
Existing 3 GeV and 50 GeV
synchrotrons HI injector and injection section in RCS are necessary
Large acceptance(transverse e>486πmmxmrad, longitudinal Dp/p>1%)⇒ Multi-turn injection of high-intensity HI beamProven performance for high-intensity proton beam Current status of MRSlowly extracted proton beam at 30 GeV 2.5x1013
/cycle (6s)1.3x1014 (2017) Well understood accelerator performance Optics, lattice imperfections, acceleration, beam lossAdvantages of RCS/MR for HI beam11/21/2014Slide50
Heavy-ion acceleration
ＲＣＳ beam loss simulationU86+
ion 4×1011
/cycleBeam loss < 0.05%HI injection section50
H
-
H
-
stripping
injection
Stripper
foil
H
-
H
+
Extraction
section
RF section
HI injection
Inj. beam
dump
HI
From H
-
Linac
From HI Booster
Collimators
section
Proton
to MLF
Proton
/
HI
to MR
Pulse
Bending (
PB
)
f
or beam switching
to MLF
to MR
RCS ring
●
No any unexpected beam losses.
●
Beam survival > 99.95% even
f
or 1.1×10
11
/b of U
86+
ions
●
Beam loss localized at ring collimator.Slide51
51Slide52
52Slide53
53Slide54
Simulation for
U86+acceleration in the RCS
54
Time [ms]
Code: ORBIT-3DSteps:(1) Single particle w/o SC(2) Multi-particle w/ SC● BM, QM, Sextuples are kept unchanged as optimized for 1MW proton (
for MLF).
Those can’t be changed pulse-to-pulse.
● rf patterns are differently used. Upgrades might necessary. (may not be a big issue.) Injection energy: 61.8 MeV/uExtraction energy: 735 MeV/u (1) Successfully confirmed by the single particle simulation.rf patterns(1)Slide55
HI LINACとHI
Booster RingLINAC とbooster
を同じ建屋に建設- スペースとコスト
の節約boosterからの出射エネルギーは可変- RCSへの様々なイオン種に対応boosterの設計- 大強度のビーム蓄積RCSには injection kickerのみ追加必要- コスト節約
5550m
HI booster
周
長：131.6mHI LINACSlide56
Charmed particles
c-c produced in the early stage of collisions
D,J/
y may be modified Probe of high density stateJ-PARC energies close to the production thresholdsD (5.07 AGeV),J/y (4.77 AGeV)May be possible with increased beam energy 12 19 AGeV/c√s= 4.96.2GeV (U)Enhancement due to multi-step processes in A+A?
56CBM Physics Book,W. Cassing, E. L. Bratkovskaya andA. Sibirtsev, Nucl. Phys. A 691 (2001) 753Slide57
Event-by-event fluctuations
Search for the critical pointand phase boundaryw/ 3rd and 4th-order fluctuations
Direct comparison to lattice-QCD may be possibleNet-chargeNet-proton
StrangenessHigh statistics in J-PARCWide y-pT acceptance required57STAR PRL112 (2014) 032302
S
Slide58
Exotic particles in HI collisions
DibaryonHLL
p-p
p-pd*(2380)dp+p-Kaonic nucleusK-ppLpp-pp
ResonancesK*(892)pKD(1232)ppS(1385)LpL(1520)
pK
-
X(1530)XpWLK-X-Lp-Penta uarksQ+(uudd sbar)pKsQ+++(uuuu sbar)pp+p+Q0(uddd sbar)pK-Ns(uudd ubar)LKS5(udds ubar)LpS5(uuds dbar)pK0barπ-pφn (udd ssbar)58Slide59
59
“d*
resonance”
70 MeV
Total cross section pn d
0
0 P. Adlarson et. al Phys. Rev. Lett. 106:242302, 2011NN*(1440)Slide60
60
Total cross section
pN d
P. Adlarson et. al Phys. Lett. B721 (2013) 229
Slide61
Simulated di-electron spectrum
(preliminary)Based on p0 spectra of
JAM Other hadrons m
T-scaledb<1fm (0.25% centrality)Momentum resolution 2%Electron efficiency 50%(No detector response)1011 events⇔100 kHzx 1 month runningeisolation
= rejection efficiency of close opening angle Dalitz pair8/28/201561Calculations by T. Gunji and T. Sakaguchif
w
r
p0Solenoid+Dipole setupSlide62
62
X. Luo, CPOD2014Slide63
Ring reconstruction
Assumed 2x2mm2 pad size of photon detectorTransform to spherical photon detector surface coordinateHough transformation : r = 32.4mm (b
=1 ring)1 JAM U+U event
63Hough clustersRing fitHough amplitude distSlide64
RICH-track association
R = 32 mmNo. of photons / ring ~ 22
64
Ring-track matching at photon detector planeRing radius vs momentumep
Number of photons / ring vs momentummpSlide65
Electron ID with p vs m2
Electron-like track cutP<3GeV/c, m2<0.017GeV/c265
Electron cocktail + GEANT
JAM + GEANTSlide66
Electron reconstruction eff
B=2TEff ~ 100% (p>=0.5 GeV/c)50% at p=0.2 GeV/c
66
generated e tracksreconstructed ringsreconstructed ring+tracksreconstructed rings/generated tracksreconstructed r
ing+tracks/generated tracksSlide67
GEANT4 (C+C @ 15AGeV/c)
Proper physics list necessary for ion-ion collisions67Slide68
JAM-1.622 (Y. Nara)
JAM-RQMD/S mode with clusteringSome physics description necessary from Nara-san15 AGeV C+C, minimum bias, 1000 events
fragment
L hypernuclei
S0 hypernucleiS- hypernucleiS+ hypernucleiNch = 33.77Nfrag=1.968NhypL=0.010Nhyp
S
=0.007
NL = 0.343hypL/L = 0.0293LH/L = 6x10-3MultiplicitySlide69
y
-pT distributions
Looks reasonableMesons peak at ymid, nucleons/fragments peak at
ybeam and ytarget69pp+
dt3He
4HeSlide70
Strategy to measure Hypernuclear weak decays
Stop produced particles except fragments and beams with a collimator after the first dipole magnet Beams pass through the hole in the TPC but a part of fragments either Z/A<0.5 or Z/A>0.5 pass the sensitive area of TPCWeak decays of
hypernucleus to pi- and a nucleus will be measured by the TPCThe secondary vertex can be reconstructed if the mother hypernucleus
passes the TPCAlternative approach is to remove beams after the target, to extract fragments with an angle with respect to the beam. In this case, we don’t need to make a hole in the TPC but measure all the fragments. An produced angle is necessary to polarize the produced hypernucleus for magnetic moment measurements70Slide71
Polar angle selection
Polar angle cut of q<10mrad with a collimator rejects most of charged particles except protons71
Charged particles
p
fragmentsq(rad)q(rad)Slide72
Bending power of magnets
X-deflection vs Z/A72
After 1
st dipole (before collimator)After 2st dipole (end of TPC)Slide73
Horizontal track positions
73
Collimator hole
All chargedfragmentsAt collimatorAt end of TPC
TPC holefragmentsCharged + fragmentIn TPCPass fragments in the collimatorBut stop other particlesMake a hole in the TPC to be insensitive
t
o the beam, but measure fragments with
Z/A<0.5 or Z/A>0.5Slide74
L magnetic moment
74
■
:B=0●:B in y+ direction〇:B in y- direction
Polarization measurement (from p asymmetry w.r.t the reaction plane)Precession angle vs BdLSlide75
Introduction
Hypernuclear production in heavy-ion collisions75
L
L
p
n
rapidity
L absorption infragmentstarget nucleusbeam nucleustarget fragmentsbeam fragmentsp+K+participantsspectators
coalescence
L
HI collision : Spectator-participant pictureSlide76
Vertex resolution
76
Barrel xca
Forward xcaBarrel zcaForward zca
Xca,zcaClosed approachOf the trackTo the targetPositionGood resolutionWith 4 layer40umx40umand 80umx80umpixelss=45um
s
=51um
s=54ums=62umSlide77
HypHI at GSI
6Li beam 3x 106 /s3.5-day experiment12C graphite target
8.84g/cm2interaction
prob 10%B=0.75TTR0-TR2 : SciFiBDC, SDC: drift chambers77p-
PositiveparticlefragmentsReconstructed decaysVertex cut required!Slide78
HypHI Results
Comparison of the absolute yields (dN/dy)6Li+12C minimum-bias cross section :
stotal =0.667b
N(L) = 2.6x10-3N(3LH)= s(3LH)/stotal = 3.9x10-6/0.667= 5.8x10-6N(4LH)= s(4LH)/
stotal = 3.1x10-6/0.667= 4.6x10-678
~3x10
-6
in p+Cat E16?p+C/Li+C~1/6Energy cor=3Slide79
Preliminary setup
79
Muon
tracker
Solenoid
(BL=1Tm)
2m2m0.3m30oTOF (5m from target)
TOF
EMCAL
GEM Trackers
RICH
h
adron-ID (
q
<110
o
)
e
-ID : q<30om-ID
: q<30o20o = ymid
at 10AGeV/c
1m
1m
RICH
Top View
target
Silicon pixel
/strip
trackers
GEM
trackers
Dipole
(BL=1.5Tm)
1.5mSlide80
80
Candidate TOF position?
Flight path ~1.25m?15<
q<45S0S1S2S3
S0:-15<q<15S1: 15<q<45S2: 45<q<75S3: 75<q<105S4: 105<q<135MRPC : 0.67mx0.67m at 1.25m distanceDq = Df = 30Fit in 1 section
S4Slide81
81Slide82
ＡＧＳ－Ｅ８８６ strangelet
search using D6-line 82Slide83
10-6~-7 sensitivity (near target rapidity)
83
PID of fragments is easy if Z can be measured
TOF
AGS-E886, A. Rusek, PRC54Slide84
84
Y. Nara, Heavy
Ion Pub
2015/07/14Slide85
RICH
Design based on HADES-RICHTarget shifted to downstream of RICH centerSlightly small theta acceptance (<80deg)But rings detected at photon detector at larger theta (avoid overlap with high density charged track at the photon detectorRadiator C5F12
radiator (n=1.002)p rejection p<3.4 GeV/c
85
1
m
RICH
R=1m0.5m1.8m0.25mPhoton detectorSlide86
Toroid (12 coil configuration)
Increasing number of coils improves phi uniformity
12 coil configuration is good
86z=250mm, R at coil centerz=750mmz=1300mm
CLAS12rf(mm)B(T)Slide87
87
Support beam/pipingSlide88
Muon ID performance
(preliminary)EMCAL (~1
lint
)+Fe absorber (~1lint)x6+GEM trackers （7 layers）・Goal π suppression：1/10 of π→μ decay probability (5m,2GeV/c):4.4x10-3Π
, μ rejection performance by simulationΠ suppression = 2-4 x 10-3 m detection eff ~70%punch through p / m (p decay) = 0.16Decay rejection by track matchingP (80%), K (95%)
88
p
+m+survival probabilitySurvival probabilityp+ and decayed m+ before/after muon absorbers p (GeV/c)p (GeV/c)p (GeV/c)p+ m+ Slide89
Baryon density at different energies
89
U+U Central
JAM modelY. Nara, et al, Phys. Rev. C61,024901(1999)Slide90
Hypernuclear physics with HI
GoalsDiscovery of new hypernuclei and extension of hypernuclear chart
S=-1,-2,-3 hypernucleiProton-rich and Neutron-rich hypernuclei
Can be done in mid-rapidity or beam/target rapidityIdentification with weak decay to a (light) nucleus + p-Study of weak decays at beam rapidityWith meson beams, due to short decay length these measurements are difficultlife time measurementMesonic decay e.g. 4ΛH→ π−+4He (4He ground state) standard way to identify a hypernucleusNon-mesonic weak decayΛp →
pn (p,n : high momentum) the rest nucleus is exited state, and will break.Measurements of residuesmagnetic moment never measured!sensitive to hyperon wave function inside hypernucleusSpin and angular momentum structureSpin-dependent YN interaction Special closed-geometry setup is required We could utilize full 1010 Hz beam? Simulation study necessary90Slide91
(T , m
B ) and √sNNFocusing effect toward the critical point in the system evolution
We can measure (T,m
B) as a function of √s with fine steps (almost continuously) and systemactically with the same spectrometerSignature for the critical point = step structure?91
A. Andronic, et al, NPA837 (2010) 65-86
?
?
M. Stephanov PRL81(1998)4816Higher √sSlide92
U+U at 5
AGeV/c
92Slide93
U+U at 1 AGeV/c
93Slide94
Rapidity and pT
distributions94
10AGeV/c
5AGeV/c1AGeV/cSlide95
Photon feasibility study
0.1 T events 1<y<2, b<1fmBlue: pi0, Black: eta, Red: decay photons from pi0 and etaDirect photon signal is assumed to be 2% of background photonsStatistical error onlyNo hadron contamination, photon efficiency is taken into account.
95Slide96
E27
96
π
+
K
+
K
+ppπ+ π+d→ K+X X=K-pp→Λ
p
→
Σ
0
p →
Yπp
p
p
Search for a K-pp bound stateNo tagging 2p : inclusive measurementTagging 2p : exclusive measurementSlide97
Missing mass spectrum of d(
π+, K+) 97
Quasi-free B.G.
- Λ, Σ+/0, - Y*: Λ(1405), Σ(1385)+/0, - Λπ, Σπ
There are a lot of B.G (quasi-free hyperon production).
→
It is difficult to identify the K-pp from inclusive spectrum.In the Λ and Σ region, observed spectrum is almost consistent with simulation.“Puzzling ” Y* peak shift = -32.4 ± 0.8 MeV/c2Y*N final state interaction might explain it?Slide98
ZCAL
Beam
Muon
Tracker
Top View
98
0.5
m1.2mGEM trackers1.4m
Dimuon
trigger
A positive and a negative particles after
6
l
(7
l
)
absorbersAt forward muon tracker system (q<33
o)Interaction rate = 107Hz
Dimuon trigger rate (background)JAM(U+U, 10AGeV/c)+GEANT4=105 (after 6l)=3x104 (after 7l)Dimuon trigger rate (signal)~104The experiment may be feasible!
SVD
0.4
m
Pb
absorbers
Dimuon
specialized spectrometer (preliminary)
0.4
m
0.5
m
Dipole
Magnetic
field
Fe
absorbersSlide99
Electron reconstruction
Cherenkov ring reconstructionMatching with electron candidate tracks99
Cherenkov Ring fit
Ring-track matchingU+U at 10 AGeV, JAMx(mm)y(mm)