EXPLORING THE HIGH-𝝁𝑩 REGION OF THE
QCD PHASE DIAGRAM WITH CBM AND HADES
Joachim Stroth
Tsukuba Global Science Week
Universe Evolution and Matter Origin

September 27, 2022

Sep. 27, 2022

Opportunities
GW170817 / GRB 170817A|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

QCD matterin the cosmos

Cosmic matterin the laboratory2

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

The State of Hesse funded Cluster ELEMENTS(Univs. Darmstadt, Frankfurt, Gießen)

WA1
equation-of-stateWA2
simulationsand GWs

WA3
nucleosynthesis

WA4

crust
composition3

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

4

Heavy-ion collisions and neutron star mergers
Gravitational wave signal can probe thedense EOS during “ring down“
if frequencies in kHZ range are detected.
Moderately dense but hot medium inthe surface region of the merger. Coldand dense in the interior.
HIC observables!?

M. Hanauske, J. Steinheimer (priv. com.)
L. Rezzolla et al. arXiv:1807.03684

H. Stöcker courtesy Jocelyn Read

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth5

Some basic facts on high 𝜇! facilities
Program needs ever more precise data andsensitivity for rarest signals

Interaction rate [Hz]108
Heavy ion collisions

CBM@FAIR SIS100

7

Fixed-target experiments

10

106
5

10

CEE+@HIAF
NA60+@SPS

o HADES: established thermal radiation at high µ! ,

BM@N
LAMPS
@RAON
HADES@GSI

104

ALICE@LHCsPHENIX@RHIC

STAR FXT

limited capabilities for rare probes

o BM@N: running (light systems);

STAR@RHIC
Collider experiments

102
10
1

2

3 4 5 67 10

limited to 20kHz and s"" =2.4 GeV

o STAR FXT@RHIC: BES program completed;

MPD@NICA

NA61/SHINE103

o CBM will play a unique role in the exploration of
the QCD phase diagram in the region of high µ!
with rare and electromagnetic probes:
high-rate capability

J-PARC-HI

20 30

100

200

Collision energy sNN [GeV]
NPA 982 (2019), update 2021 https://github.com/tgalatyuk/interaction_rate_facilities
CBM, EPJA 53 3 (2017) 60

limited capabilities for rare probeso CEE+@HIAF proposal: multipurpose detector

based on TPC; anticipated rate capability 500 kHz

o J-PARC-HI proposal: highest proton beam

intensities, addition of heavy-ion option (HIbooster); state of the art detectors (e, µ, hadrons)

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

FAIR and GSI – “The Universe in the Laboratory”

6

7|T|G|S|W| Universe Evolution and Origin of Matter | Joachim
StrothSep. 27, 2022

ProgramAgendao Motivationo HI collisions with HADESo Bulk observables
o Strangeness phenomenology
o Meson baryon couplingo Thermal radiation

Introductiono The Future at
FAIR

Emissivity of baryons
CBM & HADES
Dielectrons from cold and dense matter
Strangeness production and propagation
OutlookSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

HADES as FAIR Phase-0 Detector
Large acceptance DiElectron Spectrometer – several upgrades since 2002

8

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth9

The HADES mission
Characterize the microscopic properties of compressed baryonic mattero From medium modifications to novel phases of QCD matter

𝜌, 𝜔, 𝜙o Dynamics of meson baryon coupling

0.2 𝑞'𝑞 #C.P. / FO ?
0.8 𝑞'𝑞 #𝑞 𝑞" : lQCD

arXiv:0711.3444
arXiv:1011.0615
HADES prelim.
arXiv:0511.071
arXiv:9903-063
STAR prelim.
HADES prelim.
arXiv:1005.3508
arXiv:1308.5596

𝟎. 𝟖𝟓 𝟎. 𝟕𝟓 𝒒𝒒 𝟎
𝟎. 𝟖
𝟎. 𝟗

𝑞' 𝑞 : 𝜒 EFT+FRG

JS, JPS Conf. Proc. 26 (2019) 011013

K. Fukushima, T. Kojo, W. Weise; arXiv:2008.08436v2(also G. Baym, QNP2018)

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth10

Freeze-out conditions from SIS18 to LHC
ALICE ( 𝑠 = 2.76 𝐴TeV): 𝑻𝒄𝒉 = 𝟏𝟓𝟔. 𝟓 𝟏. 𝟓 ; 𝝁𝑩 = 𝟎. 𝟕 (𝟑. 𝟖)
HADES ( 𝑠 = 2.42 𝐴GeV): 𝑻𝒄𝒉 = 𝟔𝟖. 𝟐 𝟏. 𝟓 ; 𝝁𝑩 = 𝟖𝟖𝟑 (𝟐𝟓 ) (?)
o

Factor 1000 in beam energy / factor ~2 in temperatureoStrangeness canonical treatment at low beam energies!

o

Calculation carried out with vacuum masses!

Pb+Pb ÖsNN= 2.76 TeV
1 ppm

Nature 561, 321–330, 2018

Au+Au ÖsNN= 2.42 GeV

HADES preliminary

1 ppm

HI COLLISIONS WITH HADESSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

12

Ag+Ag – offline analysis
From recorded to clean events - reasons for losses:

10 kHz * 𝝐𝐝𝐮𝐭𝐲 (0.7)

o Reactions outside the target stacko Pile-up events

45 % losses due
to parasitic users,
beam breaks.

o Time-zero detector inefficiency

after cuts

𝑦 vs 𝑧 [mm]

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Particle identification

13

Time-of-flight (𝛽) vs momentum/charge+ 𝑑𝐸/𝑑𝑥 (Kaons, light nuclei)+ Cherenkov rings (electrons / positrons)

BULK OBSERVABLES

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Sep. 27, 2022

E-b-E Proton Distributions from 𝐴𝑢 + 𝐴𝑢

15

𝑠 = 2.42 AGeV

y0 = 0.74

HADES y − p, coverage for protons
Purity < 0.999, use β and dE/dx
Useful acceptance y = y- ± 0.5
HADES Phys. Rev. C 102 (2020) 2, 024914

Centrality is derived from thedE/dx signal in the forward
hodoscope Σ..

Analysis based on 1.6 ⋅ 10+ evts.

Loose cut on spectrometer activity
to suppress peripheral reactions.

30-40%, 20-30%, 10-20%, and 0-10%

Divided into eight centrality classes:

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

16

Corrections applied to the data
Volume fluctuations
o Corecctions of proton cumulants based on “volume

cumulants” derived from 𝑁/0, distributions in N2LO.
V. Skokov et al. Phys.Rev.C 88, 034911 (2013)
PBM et al. Nucl.Phys.A 960, 114 (2017)

Detector responseo Studied with the HADES simulation packageo Corrected using factorial moment method

M. Kitazawa, Phys. Rev. C 93, 044911 (2016).
T. Nonaka et al., Phys. Rev. C 95, 064912 (2017).
o

HADES Phys.Rev.C 102 (2020) 2, 024914

Sep. 27, 2022

17

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth𝑁𝑝 scaling of factorial cumulants 𝐶𝑛
3

C1 ∝ 𝑁2
𝛼 = 3.89 ± 0.14

8 centrality bins (color,
5% steps)
5 rapidity bins(sequence)y ∈ 𝑦 + Δ# (Δ# =0.1 … 0.5)

HADES
Au+Au 1.23 A
GeVcharacteristic 𝑁$ scaling
indicates long-range correlations
Bzdak, Koch, Strodthoff, PRC 95,
054906 (2017)3

C4 ∝ 𝑁2
𝛼 = 1.86 ± 0.04

3C5 ∝ 𝑁2
𝛼 = 2.84 ± 0.05

Thermal susceptabilities → fluctuations of conserved charges:" $#𝜒! = − # $%with 𝑥 = 𝐵, 𝐶, 𝑆&

diverges at 𝑇'
𝐶% = 𝐾%
𝐶& = 𝐾& − 𝐾%
𝐶' = 𝐾' − 3𝐾& + 2𝐾%
𝐶( = 𝐾( − 6𝐾' − 11𝐾& + 6𝐾%
𝐾) : cumulants𝐶) : factorial cumulants/correlator

STAR, PRL 128 (2022) 20, 202303
HADES, PRC 102 (2020) 2, 024914

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

18

Performance studies in CBM (simulations)
Corrections for volume fluctuations and conservation laws
Event-by-event changes of efficiency
Impact of theeffects is being
Proper selection of pT – y bite
scrutinized(Net-)baryons vs. protons, neutrons, nuclei

Crucial:centrality determination withindependent detector
à avoids bias on e-b-efluctuation observables

After 3 years of running:• Completion of the excitation function for κ1 (p)• First results on κ7 (p)• Extension into strangeness sector κ1 (Λ)

Low pT and midrapidity coverage(better than STAR s66=3 GeV)
Reconstruction efficiency allows for
precision measurement of cumulants

Statistics sufficient to study
derivatives of order > Ο(4)Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

19

Proton higher-order flow components (𝐴𝑢 + 𝐴𝑢 𝑠 = 2.42 AGeV)The collective motion (flow) of protons,
deuterons and tritons shows a distinct
pattern which encodes properties ofthe fireball (e.g. equation-of-state).
Hillmann, Steinheimer et al., J.Phys.G 45 (2018)

The flow is encoded in the transverse
mass spectra and in the angularvariation of the yields.

;d𝑁∝ 1 + 2 ] 𝑣8 cos 𝑛 𝜑 − Ψ8d𝜑
89:

HADES, Phys. Rev. Lett. 125 (2020)

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

20

Sensitivity to the EoS: v3{YRP} and v4{YRP}
UrQMD with Skyrm potential– EOS A + coalescence in space and momentum

preliminary

p

EOS

A

B

a (MeV)

-124

-356

b (MeV)

71

303

g

2

1.17

preliminary

preliminarydp“... this ansatz provides a very good description of the measured deuteron flow data, if a hard equation of state is used ...“
[P. Hillmann, J. Steinheimer, M. Bleicher, J.Phys G45 (2018) 085101]

STRANGENESS PHENOMENOLOGYSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Universal strangeness centrality dependence
Strangeness production at
SIS18 energies enabled bymedium-effects
Suggests density-dependenceof production
𝑁𝑁 → 𝑁ΛK <:s = 2.5 GeV

𝑁𝑁 → 𝑁𝑁𝐾 <𝐾 =:s = 2.9 GeV

Data can be explained with asingle slope:𝜶

𝑴𝒊 ∝ 𝑨𝐩𝐚𝐫𝐭 .

22

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Refined fits including light nuclei

23

A

B

C

https://github.com/vlvovch/Thermal-FIST (V. Vovchenko, HS)
Comput. Phys. Commun. 244, 295 (2019), 1901.05249 [nucl-th])

𝑻 [𝐌𝐞𝐕]

64.0 ± 1.2

64.2 ± 1.1

66.2 ± 0.7

𝝁𝑩 [𝐌𝐞𝐕]783 ± 2.5782 ± 2.5801 ± 1.5

A: strangeness canonical, excited nuclear states
B: grand canonical, excited nuclear states
C: strangeness canonical, w/o excited nuclear st.

𝑹 [𝐟𝐦]

9.9 ± 0.2

9.9 ± 0.17

8.7 ± 0.14

𝑹𝒄 [𝐟𝐦]3.39 ± 0.4−

2.68 ± 0.14

𝜸𝒔

10.056 ± 0.007

1

𝝌𝟐

2.5

3.5

6.5

all non-interacting gas, const. Breit-Wigner width
HADES
work in progressSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

24

Canonical suppression of strangeness production (?)
ooDeviation from grand canonical behavior clearly observed
Strangeness canonical description near to the data

G.N. Xie for STAR 2108.05424 [nucl-ex]

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth25

Hypernuclei measurements in Ag+Ag systemooBased on 6 B events
In line with results from other HI
experiments (STAR, ALICE)MESON BARYON COUPLING

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

The HADES Pion Beam Facilityo Pion production target 40 m upstream theexperiment target positiono Direct excitation of baryon resonance and exclusivereconstruction of final stateso Combination with dilepton spectrometer world-

wide unique27

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth28

Extraction of partial waves from two-pion channel

Ø 𝑝; = 656, 690, 748, 800 MeV
o 𝜋< + 𝑝 → 𝜋< + 𝜋= + 𝑛– Hadronic final states used in PWA– (Bonn/Gatchina code)– Use invariant masses and angular
distribution.
o 𝜋< + 𝑝 → 𝑒< + 𝑒= + 𝑛–

Prediction for dilepton invariant mass
assuming strict VMD.

–

Two-component model.

HADES Phys. Rev. C 102 (2020) 2, 024001

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth29

𝜋& + 𝑝 → 𝑒'𝑒& + 𝑛 ( 𝑠 = 1487 𝑀𝑒𝑉)
Effective transition form factor (time-like) extracted
by subtracting QED expectation from exclusive
invariant mass distribution.
Resonance-Dalitz decay (VMD ?)is analogous to baryonic contribution to in-medium𝜌 selfenergyD, N(1520), …

>
>

r

h

HADES arXiv:2205.15914 [nucl-ex]

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

30

Pion cloud effect in Δ(1323)
o Exclusive dielectron production in p+p collisions.
o Effect of the pion cloud observed in the time-likeelectromagnetic transition formafactor(off-shell 𝜌 meson).

Peña, Ramalho; arXiv-1205-2575
Peña, Ramalho + GiBUU.; arXiv-1512-03764

o Moderate contribution to the in-medium propagator

π
π

r

π

B*,a1

Δ
N-1

N,𝜋

r

ll+
HADES: arXiv:1404.2136 [nucl-th]THERMAL RADIATIONSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

32

Theoretical approaches to medium radiation
Medium (excess) radiation from Thermal Emission Rates 𝝐 (“standard candle”):𝑑? 𝑁
𝛼 B 𝐿 𝑀B=- C B𝑓@ 𝑞 ⋅ 𝑢; 𝑇 ImΠDE 𝑀, 𝑞; 𝑇, 𝜇@ 𝑑𝒙
𝜋 𝑀 𝑀B𝑑𝑀𝑑𝑦𝑑𝑝A 𝑑𝛼
𝑑? 𝜖≡𝑇 𝒙 , 𝜇@ 𝒙 , 𝑣⃗ 𝒙 𝑑𝒙
𝑑𝒒coarse graining

shining

F. Seck, MSc 2015

UrQMD

or

isentropic expansion,hydro𝜌i, 𝑇i, 𝑉i

Dilepton emission fromMicroscopic Transport.

Sep. 27, 2022

33

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Thermal dileptons Au+Au ( 𝑠 = 2.4 𝐴 GeV)o Microscopic transport(2):• Vacuum 𝜌 spectral function and Δ regeneration• Explicit broadening and density dependent massshift

o Coarse-grained UrQMD(3)• Thermal emissivity within-medium propagator (4)• 𝜌 − 𝑎: chiral mixing(5)(not measured so far)

HADES, Nat. Phys. 15(2019) 1040

(4) Rapp, van Hees; arXiv:1411.4612v(2) E. Bratkovskaya;(3) CG FRA Endres, van Hees, Bleicher;arXiv:1505.06131
CG GSI-TAMU; Galatyuk, Seck, et al.
arXiv:1512.08688(4) Rapp, Wambach, van Hees;
arXiv:0901.3289(5) Rapp, Hohler; arXiv:1311.2921v

Sep. 27, 2022

34

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Strothπ
1/Nπ0 dN4excess/dMee [GeV/c2]-1

Thermal dileptons Au+Au ( 𝑠 = 2.4 𝐴 GeV)
10−2

o

Au+Au sNN=2.42 GeV−310〈Tfireball〉 = 71.8±2.1 MeV/kB

10−4
10−5

Coarse-grained UrQMD(3)– Thermal emissivity within-medium propagator (4)– 𝜌 − 𝑎: chiral mixing(5)(not measured so far)
– Finer grid for calculation ofemissivities at high 𝜇> andmoderate 𝑇.

10−6
−7

10

HADES data 0-40%
in-medium ρ spectral function
3/2

−8

10

0

Mee × exp(-Mee/ 〈T〉)

0.2

0.4

0.6 0.8 1 1.2
e+e- invariant mass [GeV/c2](4) Rapp, van Hees; arXiv:1411.4612v(2) E. Bratkovskaya;(3) CG FRA Endres, van Hees, Bleicher;arXiv:1505.06131
CG GSI-TAMU; Galatyuk, Seck, et al.
arXiv:1512.08688(4) Rapp, Wambach, van Hees;
arXiv:0901.3289(5) Rapp, Hohler; arXiv:1311.2921v

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth35

CBM dielectron performance (first 3 years, 5 days / energy)
Isolated dielectron thermal radiation yield, corrected for acceptance x efficiency:• Dominated by 𝜌 contribution at low mass (𝑀ℓℓ <1GeV/c2); can be reconstructed with precision of 1.5 – 4.5%
- allows fireball lifetime measurement- transport properties – electrical conductivity?

−6

10

10−7
10−8
10−9
10−10
0

0.5

1

1.5

2

M ee

2.5

(GeV/c 2)

min-bias, IR =100kHz

10−4

2×10 ev 'measured'
thermal radiation
Rapp in-medium SF
Rapp QGP

10−5
−6

10

10−7
10−8
10−9
10−10
0

0.5

1

1.5

2

M ee

2.5

10−3

min-bias, IR =100kHz

2×1010 ev 'measured'
Rapp in-medium SF

10−4
10−5
−6

10

10−7
10−8
10−9
10−10
0

0.5

1

(GeV/c 2)

𝑇 vs. baryon density effects
from partonic to hadronic fireballs

1.5

2

M ee

2.5

(GeV/c 2)

10−1
10−2
10−3

CBM Simulations
Au+Au sNN=2.9 GeV
min-bias, IR =100kHz

2×1010 ev 'measured'
Rapp in-medium SF

10−4
10−5
10−6

3.5×10& raw pairs

10−5

10−3

10−2

CBM Simulations
Au+Au sNN=3.2 GeV

1/Nev dN/dM ee (GeV/c 2)-1

10−4

2×10 ev 'measured'
thermal radiation
Rapp in-medium SF
Rapp QGP

10

10−1

4.9×10& raw pairs

min-bias, IR =100kHz

10−2

CBM Simulations
Au+Au sNN=4.1 GeV

1/Nev dN/dM ee (GeV/c 2)-1

10−3

10

10−1

1.1×10% raw pairs

10−2

CBM Simulations
Au+Au sNN=4.9 GeV

1/Nev dN/dM ee (GeV/c 2)-1

10−1

1.4×10% raw pairs

1/Nev dN/dM ee (GeV/c 2)-1

• Intermediate mass range (𝑀ℓℓ>1GeV/c2) accessible, statistics will not (yet) be sufficient to extract physics

10−7
10−8
10−9
10−10
0

0.5

1

1.5

2

2.5

M ee (GeV/c 2)

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

36

DILEPTON SIGNATURE OF A FIRST-ORDER PHASE TRANSITIONoo𝑒𝑚 spectral function from FRG
flow equations
dilepton rates at
CEP 𝑻=𝟏𝟎 𝑴𝒆𝑽, 𝝁=𝟐𝟗𝟐 𝑴𝒆𝑽

Seck, Galatyuk, Mukherjee, Rapp, Steinheimer, Stroth,Phys.Rev.C 106 (2022) 014904
Feng Li and Che Ming Ko,
Phys. Rev. C 95 (2017) no.5, 055203

Hydro with PT

120
110
100
90

10

80
70

1

60
50

−1

10
40
0.5

1

1.5

2

2.5

3

3.5

4

4.5

ρ /ρ
B

0

spectra ratio: with PT / no PTodilepton radiation inhydrodynamical simulations
factor of ~2 extra radiationin case of hydro with PT

4-volume (fm4/c)o

T (MeV)

Tripolt, Jung, Tanji, v. Smekal, Wambach,Nucl. Phys. A982 (2019) 775
Jung, Rennecke, Tripolt, v. Smekal, Wambach,Phys. Rev. D 95 (2017) 036020

2.4

inmed. SF rate
qq rate

2.2
2
1.8
1.6
1.4
1.2
1
0

0.2

0.4

0.6

0.8

1

1.2

1.4

Mee (GeV/c2)

THE FUTURE

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

The Future at FAIR
Shell construction accelerator tunnel finished38

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

Painting of CBM cave started

39

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth40

The C.B.M. experiments
Systematic exploration of baryon dominated matter in A+A collisions from 2 − 11 𝐴 GeV beam energy

ction in the CBM experiment

Entr

Entr

Tracks/ µs

Entr

Entr

Entri

Entri

Entri

Tracks/ µs

pressed Baryonic M

Entri

Λ
Sigma
Sigma
Sigma
2
Sigma
1.3
1
1.2
Sigma
Sigma
Sigma
2
Sigma 0.88 1
0.88
1.3
Ω+ 1.2rm andKF Particle
Finder90
2160
depicts
Efficiency,2 %3D
0.1 MHz
10 MHz80
Sep. 27, 2022
|T|G|S|W| Universe Evolution andOrigin of Matter | Joachim
Stroth41
140
central1
1 collisions
Event Selection
1
70
All tracks
92.5 193.8
91.7
1ansport
1
120
1
1
60
MC
QualityCheckhemical100
Ghost level
1.8
0.6
0.6
50
undant80• CBM is the future fixed-target heavy-ion experiment40
Figureof1.4: Particle
multiplicities times branching ratio for central Au+Au 0collisions at 25 AGeV
0 0
0
0
0
ecay
0 13.60
Time, model
ms/ev
11.70 0 −5time-slice
11.97
−5 −5
0 t0
5 5
−5
0
5
−5 60
0
5
−5
0
5
−5
0 the vector
505instead of−5 isolated
05collisions
30
atthe
FAIR.
as
calculated
with
HSD
transport
code
[12]
and
the
statistical
[14].
For
2
•
Cellular
Automaton
trackfinderfor track search Pullin tthe/137) ,
Pull
t
Pull
q/p
Pull
x
x
Pull tx
Pull q/p
Pull xPull t Intel Xeon
2 decay into lepton pairs• was340
mesons (ﬂ, Ê, „, J/Â, Â Õ ) the
assumed,forDmesonsthehadronic
20
efficientand (e.g.
stable track reconstruction;
Silicon Tracking System (STS).Intel Xeon Phi• Observables include extremelyrare probes
to theE7- 4860
decay into kaons and pions.
20• Free streaming data.
105110P
6 collisions).
one Ω̅+ per 10event•
Kalman filter based
fitter for track parametersa)b)track
Real-time
selectionfromfree-streaming
data
with
the
• vectorised and parallel algorithm;
0
0
0
10
20
30
40
50
60
70
80
0
50
100
150
200
250
• Continuous time-slices instead of individualn cross5
7
Numberof
LogicalCoresestimation.
Number of Logical Cores• Unprecedented rates of 10 -10 collisions per
Level
Event
Selector• linear(FLES).
scalability on parallel computer
systems;
collisions.
11.3
MHz.CBMFirst
physics
cases
observables
Linearscalabilityondifferent
systems
second withup andto 1000
charged particles are• Event
Finder based on
400 the obtained set of tracks.
120
rated Up
tp 1 isTB/s– fullyinspected
inperformancereal time comparable• On-line time-based
requiredsufficientin measurements.
• time-basedwith event-based
The CBM research
program forfocusedon thestatistics
following
physics
cases:• KF parameters
Particle Finderwith
for350short-lived
particles• unbiased tracka high resolution;n collision reconstruction• tracks

2, Ivan Kisel1,2,3, Maksym Zyzak2, Iouri
Vassiliev
CBM high-rate operation – FLES

ity, Germany, GSI, Darmstadt, Germany, FIAS, Frankfurt, Germany

Intel Xeon E7-4860, 2.27 GHzIntel Xeon Phi 5110P, 1 Ghz

Tracks/ µs

Tracks/ µs(for the CBM Collaboration)vel Data-processing
Conceptof CBManditizatiois required in the first trigger
analysis;reconstruction and physics analysis.
Observables have complex signatures,no simple
Digselection• correctly estimatederrors;
100

3

3

Mean
Sigma

0.0018

based

300

Mean
0.0013level.

×103

3
×10
×103

Mean
Mean −0.053
0.18
Sigma
16
Sigma
1.1

×103

Mean
Sigma

0.0018

×103

Mean
Sigma

0.0013

×103

Mean

0.18

250
• Module
for a Sigma
quality 1.1
check.
0.018

1.2

0.1 MHz00

0.6

0−4500−010−5−150

5 0.1

0
×10
0

3

150
00

450
5 10

Entries

Entries

3
3

3

00 0
−2 −5−5350
50

Event Finder1Λ→p→π- pπ- 1 Λ
Λ
→
p
π
→ pπ
KF ParticleΛFinder

00 0

0

5 52
−5
00
−0.1
Event
Selectionreco

Residual (treco
- tmc
Pull
x ) [mrad]x
Pullx t3

Entries
Entries

3

Residual (p3

10 MHzt332Λ σ = 1.7
Λ MeV/c
σ=
80 1.7 MeV/c2
ΛS/B
σ == 1.7
ΛMeV/cσ ==1.7 MeV/c2
8.42
70 8.42
S/B
1
S/B 1= 8.42
S/B =60 8.42

0.1
80

0

0
0

10

Residual (treco - tmc) [ns]Mean −0.011
0.18
Mean
Sigma
1.1
Sigma
1.3

12

×103
2

Mean
Sigma

0.18

20

40

60

80

100
120
Local Item SizeKF Particle

1

10• short-lived
particles are of particular phy
2• particles are reconstructed via decay pro
110• events from event finder serve as input f
00
−5
−10

5 0.1

mc)/ptmc- pPull
x

00

5

0

10

−5

0

5

1 Pull t• time-based
reconstruction performance
0
2000
4000
6000
8000
10000
0.18
procedure;Time [ns]1

Residual (treco Pull
- tmc)q/p
[ns]

0
0 1.1
0.5
0.6
0.5
0.6
1.1
1.2
(x, y,×Checktx-,1.2
ty, q/p,t)
×10 ×10Mean
10×10−0.010.18State
Mean
Mean
−0.011Mean−0.011
Mean
Quality
0 ×10 vector:
0 1.1 0.0066
2
2
+ 2
22
+
0.5
0.6
Sigma
Sigma
0.5
0.6
1.1
0.88
1.3
1.2
m
{
π
π
}
[GeV/c]minv {pmπ 1.2} Sigma[GeV/c]Sigma inv1.3 m2{π π Sigma} [GeV/c 1]{pπ-1.2} [GeV/c
]
3

2
2
+ inv
minv {πmπ2inv} [GeV/c]{π+π-90} [GeV/c
]
2

0 60

Entries

40

Residual (preco - pmc)/pmc

Entries0
2 0

0Residual (treco- tmcx ) [mrad]x

Entries
Entries

Entries
Entries
Entries

Entries
Entries350500.511mc) [µmc
Residual(xreco -(txreco
Pull
Residual- t m])q/p[ns]mc)/ptmc
Residual (preco - pPullx

Entries
Entries

1.8

3

Entries
Entries1
1

1
time-slice
instead of92.5
isolated collisions
All tracks
93.8 20 20 91.7
20
20
1

3

inv
2
2
minv {pmπ-160} [GeV/c]{pπ-} [GeV/c
]
- inv
2
-

Mean
MC
Sigma

Ξ σ = 2.6
Ξ MeV/cσ = 2.6 MeV/c2
140
-1
2
ΞS/B
σ ==2.6
MeV/c
ΞS/B
σ ==2.6
MeV/c2
11.7
11.7
1
120
S/B = 11.7
S/B = 11.7

• Monte-Carloparticle identification is curr
102

• Cellular Automaton track finder for track search in the• work in progress: multi-vertex analysis a1

Silicon Tracking System (STS).

0.6

100

100
100
80 - + 40 +Ξ- →
Λ
100 0 100Ξ→
Λπ5-track 0parametersΛ→p-0 for
0 •π
0
-π
Λ
→
p
π
0
Kalmanfilter−5 +0 0+ 5 5−5 based0
5 track fitter
−5 60
−5
0
5
5
−5
30
Ξ
→
Λ
π
Ξ
→
Λ
π
Λ→pΛπ→pπ5010Conclus0
0 13.60
Time, ms/ev
11.70 0 −5
11.97
−5
0
5
0
5 10
0
10−5
Particle
FinderPull tPull q/p
Pull Pullx t Intel Xeon
Pull tPull
t 10• Continuous time-slices
Pull q/p
insteadofindividual
Pull x10
estimation.
Intel Xeon Phi• efficient and stable track reconstruction;
Reconstructed
E7- 4860
Reconstructed
track timein STS
5110P
packageis efficient, fast and• The 1FLES
collisions.
track time in STSb) obtained set of tracks.
• a)
Event Finder based on the• vectorised and parallel algorithm;
4300
4350
4400
4450
4500
4550
4600
and
task
levels.
•• On-line
time-based
collisionreconstruction
0
0 Finder0 1.1
0Time [ns]linear scalability
on parallel
computersystems;• 1.2KF1.2
Particlefor1.3short-lived
particles
1.4
1.1
1.4
Linearscalability
on different
systems
0
0 1.3
0
0
2
2
+
1.1
1.2
1.3
1.4
1.1
1.3
1.4
2
2
selectionis requiredin the first
trigger• The reconstruction chain of CBM is beinminv {pmπinv}1.2[GeV/c]minv {Λmπ- inv} [GeV/c]{pπ++} [GeV/c{Λπ- } 2[GeV/creconstruction
andphysics
analysis.
• andtime-based
performancecomparablewith event-based
2 ]track parameters
2 ]
2
+
high
resolution;{•pπunbiased} [GeV/c]×10 Mean{Λπ } [GeV/c]• tracks are split into collision-corresponding groups
minv
πMean
} [GeV/c]minv with{Λm
πinv} a[GeV/c
]
×10
×10
Mean
0.0018×10{pm0.00130.18
inv
×10 level.
Mean
0.0013×10 Mean
Mean −0.053
0.18
analysis;10
streaming
data processing.
2
Sigma
Sigma
Sigma
• •Modulefora Sigmaquality
check.
16
0.57
0.018
1.1
correctly
estimated
errors;basedon the evaluated
time;
2
Sigma
Sigma
0.018
1.1
• 4D tracking is able to recover speed
andefficienciesof1strong scalabilityon MCvarious300k
mbias AuAu 10 AGeV• events
at 10 MHz,PIDcomputer systems;Itallowstoreconstructindividual
events•• adding all sub-detectors information
is in progress;
x

40
20

0
0

0
0

30

40

100

80

50
60
70
80
Number of Logical Cores

Tracks/ µs

20

Tracks/ µs

10

400

3

Entries

Entries

3Intel Xeon Phi 5110P, 1 Ghz

10

120

3

3

Entries

Entries
Entriesx

20Intel Xeon E7-4860, 2.27 GHz

3

3

Entries0.57

00.00660

3K00s→K5π+0s10+2→π-- π+π-Ks →K
πsπ
→π+π

0
−5
−0.1

52

Mean
Sigma

1

Ghost level

450
10AMD Radeon HD 7970, 925 MHz50

0100 −10120
Local Item Size

Entries3D020−0.1

Entries

×103

0 150

Entries

0.88

−150

Residual(xreco- xmc
Residual(treco- t)mc[µ) m][ns]

Tracks/ µs

−0.01

0
−2

Nvidia GTX 480, 700 MHz

4D Kalman Filter Track Fit

Entries
Entries

Efficiency,2 %0Entries
Entries

Mean
Sigma

Entries

Entries×103−5

Residual (treco- tmc
Pull xx ) [mrad]
x

3

3
3

10
10

Entries00.1

Entries0−20collisions

450• Free streaming data.

ressure10
10

CA Track Finder
1500Residual (preco - pmc)/pmc

100

c)
d)
Strange
Particle
Reconstruction
Time-slices
EventinFinderCA Track Finder

00
−450
−10

Entries
Entries

0.51

−150

1

20

Tracks/ µs

5

0
−450

40

150

0.5

Entries
Entries
Entries

1
2

5

0
−0.1

2

Entries

3
××10
103

0

Residual (treco - tmcx ) [mrad]• adding

Parallel and SIMD-ised algorithm allows for timeslice-based recons

1

Entries−0.053

200

2

2

x 3
0
2
2
0
×103 ×10
103 ×103
Ks σ = 4.3
Λ×10
σ = 1.8
Ks MeV/cσ = 4.3−0.053
MeV/c2 ×Λ MeV/cσ = 0.0013
1.8 MeV/c2 ×10
××10
Mean
0.0018
Mean
10
×10
×10
Mean
0.001810Mean0.0013 0 10 ×10××1010Mean
Mean2 −0.011
0.18
−0.01
Mean
0.0066
3 ××10×103 Mean
Mean
−0.01
Mean
0.0066
Mean
Mean 3 KF
0.18Track2
3
Fitter
0
2
×
10
×
10
2σ =
KS/B
4.3
MeV/c
ΛS/B
MeV/c
Sigma
Sigma
Sigma
×10
×
10
16 1.1
0.57
0.018
=1.8
12.2
s σ == 9.16
Sigma
Sigma
K
σ
=
4.3
MeV/c
Λ
σ
=
1.8
MeV/c2
S/B
=
9.16
S/B
=
12.2
2
Sigma
Sigma
Sigma
0.88
1.2
0.57
0.018
20
s
Sigma
Sigma
Sigma
2
Sigma
p
0.88
1.3
1
20
reconstructed tracks 1.2
1
S/B = 9.16
S/B = 12.2
S/B = 9.16
S/B = 12.2
2
20
20

Entries
Entries
Entries
Entries

Mean

0
−2

450

Entries
Entries

×103

Residual (xreco - xmc) [µm]0.0018150Λ

Ω+

5 AGeV
vectoradronic−150

Residual (xreco - xmc) [µm]Entries
Entries

Entries

4D Cellular Automaton Track Finder
10

1

2

First Level Event Selection
FLESPackage (FLES)

Κ+
0

Sigma
CBM STS detector
hits 16

80

0.57
60

• The excitation functions of multi-strange
π+ hyperon5 yields in Au+Au and0.5 C+C collisions atenergies from 2 to 11 AGeV (SIS100). At subthreshold energies, andhyperons are

−450

Sigma

2

Entries1

Entries
Entries

Entries

Entries

Entries

16
0.57
0.018
• 4D tracking
is able to recover
speed andefficiencies of
AuAu(UrQMD)• strong scalability on various computer systems;• The excitation functionof the collisioncollective flowof hadrons which is driven by the pressure
event-based
analysis.
Geometry
Hitscreated in the early fireball (SIS100);Rare probe measurements require novel data-processing
concept.
Sigma

10

Event Finder•
The equation-of-stateof baryonic matter at neutron star densities.
×10
Mean−0.053×10
The relevant measurements
10
hardwareare:
triggers.

350
300
250

50

100

150
200
250
Number of Logical CoresSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

The Green Cube at GSI as FLES

Up to 40.000 processor cores forseen for event selection

42

Sep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

43

Preliminary CBM program for the first 3 years

Year

Setup

Reaction

Beam Energies
Tlab [AGeV]

Days on Target

Number of
eventsRemarks

0

HAD/ELEHAD

C+C, Ag+Ag, Au+Au

2,4,6,8,10,max

60

Commissioning

1

ELEHAD

Au+Au

2,4,6,8,10,max

30 (5 each)2∙1010 each

EB minBias

1

ELEHAD

C+C

2,4,6,8,10,max

18 (3 each)4∙1010 each

minBias1

ELEHAD

p+Be

3,4,8,29

12 (3 each)2∙1011 each

minBias

2

MUON

Au+Au

2,4,6,8,10,max

30 (5 each)2∙1011 each

minBias

2

MUON

C+C

2,4,6,8,10,max

18 (3 each)4∙1011 each

minBias

2

MUON

p+Be

3,4,8,29

12 (3 each)2∙1012 each

minBias

3

HADR

Au+Au

2,4,6,8,10,max

12 (2 each)4∙1011 each

EB + Selector(s)

3

HADR

C+C

2,4,6,8,10,max

6 (1 each)8∙1011 each

3

HADES

Ag+Ag

2,4

28 (14 each)1010 each

3

ELEHAD

Ag+Ag

2,4

8 (4 each)2∙1010 each

minBiasSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth

HADES during FAIR Phase-0<1A
Au+Au BES

GeV

G-PAC
Proposed ton form
EM transitio
peronsfactors of hy

effects
Cold mattere
including lin RCSdnashapes44

15 Billion events Ag+Ag taken in 2019,the only HADES Phase-0 run so far!
nances,Baryon resoonmeson bary e 3rdthcoupling ingion
resonance re

cts
Iso-spin effe
in dilepton
production

in 2022
Completedd yet
Not submitte

G-PAC
Proposed tod yet
Not submitteSep. 27, 2022

|T|G|S|W| Universe Evolution and Origin of Matter | Joachim Stroth45

Summaryo HADES aims at a comprehensive program during FAIR Phase-0.
o

Au+Au BESoCold matter studiesod, p, 𝜋 beam induced „elementary“ reactionso Upgrades of the detector to enhance physics performance and enable reconstruction of exclusive

channels in proton induced reactions.

o Strangeness production still not fully understood in transport model calculations. Thermal

description work reasonably well.

o Very consistent picture of the dilepton continuum.
o Many data on multi-differential observables thanks to high statistics (Bayesian analysis). Will be thehunting ground of CBM.

o Prepare for BES with CBM & HADES. Unique opportunities to exploit rare probes.

THANK YOU