NTRODUCTION : : Su INT Sumit Ba Basu su Lu Lund Un University ty, , Departm tment t of of Physics, , Divi Di vision of of Particle Physics, , Bo Box 118, 118, SE-221 221 00, 00, Lund, Sweden ema email: sumi umit.ba basu@ u@cer ern. n.ch h
1 I am from India • Ph.D (2016) ( VECC & • ALICE Expt. CERN) Post-Doctoral Fellow • (Wayne State University, USA) (Dec 2016 – Mar 2020) and Now, Post-Doctoral Fellow • (Lund University, Sweden) 2018 à Sumit V2.0
Ph.D.: Temperature Fluctuations 2 Sources Temperature (T) ( L. Stodolsky, Phys. Rev. Lett. 75, 1044 (1995) ) 1. Initial State fluctuations Chemical Freeze-out 2. Thermodynamical fluctuations Kinetic 3. Statistical fluctuations Phy. Rev. C 94 034909 (2016) Chemical potential (μ) b 2 ∫ p T F ( p t ) dp T 8 STAR Au+Au 0-5% ⎛ ⎞ F ( p t ) ~ exp − p T p T = a STAR Cu+Cu 0-10% 7 ⎜ ⎟ b HRG ⎜ ⎟ ∫ p T F ( p t ) dp T eff HM ⎝ ⎠ 6 a T HM via QGM 〉 N QGM 5 C AMPT 〈 c v = C n = C = 4 Sp. Heat dN/dp T VT 3 v c 3 2 70 ----- 3 SB limit = N ∆ = VT ∆ 〈 〉 T , T , µ µ 60 ch ch B B 1 Lattice prediction T , µ = 0 T , µ = 0 a b kin kin B B 50 p T 0 2 3 40 10 10 10 C ∆ = S (GeV) v 30 c NN 20 10 0 2 3 10 10 1 10 S (GeV) NN
Ph.D.: Multiplicity Fluctuations 3 ω ch = h N 2 ch i � h N ch i 2 = σ 2 h N ch i µ where, N is the charged particle multiplicity k T expressed in fm 3 GeV -1 Phys. Lett. B784 (2018) 1-5 k T = − 1 # ∂ V & % ( V $ ∂ P ' T $ % ) + ,- ) ! " = ! * " = < ' > % < ' > ! * "
Two-particle transverse momentum correlations 4 Sean Gavin et. Al PRL 97 162302 (2006) PRC 94 024921 (2016)
Sean Gavin et. Al 5 Two-particle transverse momentum correlations PRL 97 162302 (2006) PRC 94 024921 (2016) PLB Phys Lett. B, Volume 804 (2020) 135375 Ongoing further developments: Extend this study for pp and pPb and study the variation of G2 observable with dNch/dη Promising results, soon will be reported from ALICE, about System size dependence of G2 (Momentum Correlator)
6 General D Ge Defi finiti tion o of B f Balance F Functi tions d σ C 2 ( x 1 , x 2 ) = ρ 2 ( x 1 , x 2 ) − ρ 1 ( x 1 ) ρ 1 ( x 2 ) ρ ( x ) = 1 Cumulant x ≡ { y , ϕ , p T } σ dx R 2 is a robust observable! C 2 ( x 1 , x 2 ) Single track efficiencies R 2 ( x 1 , x 2 ) = Normalized Cumulant ρ 1 ( x 1 ) ρ 1 ( x 2 ) cancel out of the ratio LS = 1 { } 2 ( ++ ) + ( −− ) 4 different charge combinations for R 2 : US = 1 { } (+ -), (- +), (+ +), and (- -) 2 ( + − ) + ( − + ) CI = 1 { } 2 LS + US Charge Independent (CI) combinations For Charged particle, Signs (+) & (-) represents charge. CD = 1 { } Charge Dependent (CD) combinations 2 US − LS For Λ’s being neutral particle, we define (+) for baryon number & (-) for antibaryon number. R 2CD is proportional to the Balance Function Similary, LS means same-type Baryonic CD = dN ch + − − R 2 ++ + R 2 − + − R 2 B ( Δ x ) ≈ dN ch 1 ⎡ ⎤ −− dx R 2 2 R 2 number and US means opposite-type ⎣ ⎦ dx Baryonic number
Im Import rtance of Studying Balance Functions 7 Conservation of quantum numbers. -> for each positive general charge, a negative balancing charge produced at approx. the same space-time. The width of the BF was initially proposed to be related to the time of hadronization. Understand / Probe 1. Two-wave quark production model: π ± p( 𝒒 ) : predominantly produced at late stage K ± : predominantly produced at early stage 2. Collision dynamics, e.g., radial flow 3. Hadro-chemistry – Charge / Strangeness / Baryon / Resonance production Pratt PRL. 108, 212301 (2012) # of quarks Bass, Danielewicz, Pratt PRL 85 2689 (2000)
Tw Two-pa particl cle N Num umbe ber (Δ η ,Δ φ ) Co Correlations 8
Mo Motiva vation: 9 h ✓ h Q
Mo Motiva vation: π K p Balance Functions 10 h π k p ✓ h Q Q π ? ? ? k Q S ? ? ? P ? ? ? Q B # of quarks Run I : Pb+Pb @ 2760 GeV
Strange Meson Non-Strange Baryon Non-Strange Meson Charged Hadrons = 11 = Kaon (K ± ) = Proton (p( ̅ 𝑞 )) = Pion (π ± ) Strange( )+ Non-Strange( ) Centrality ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV NN NN NN NN NN NN p ± p ± £ £ ± £ £ 0.2< p <2 GeV/ c 0-5% 0.2 p 2 GeV/ c K 0-10% 0.5 p 2.5 GeV/ c p p 0-20% T T T 0.15 0.06 0.4 ) -1 ) (rad ) ) j 0.3 0.1 0.04 j D D y, j y, 1. What about 𝝡 0.2 D D D 0.02 0.05 B( y, B( 0.1 D Strange Baryon ?? B( 0 0 0 - - - 1 1 1 - 0.5 0 0 0 D D D 4 4 0.5 4 y 1 2 y y 2 2 1 0 2. Strange Baryons: 0 1 0 (rad) D j j (rad) d ) D D j ( r a Lambda ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV NN NN NN NN Cascade NN NN p ± p ± ± 0.2< p <2 GeV/ c 30-40% £ £ £ £ 0.2 p 2 GeV/ c K 30-40% 0.5 p 2.5 GeV/ c p p 20-40% T T T 0.15 0.06 Omega 0.15 ) -1 ) (rad ) ) j 0.1 0.04 j D 0.1 D y, y, j D D D 0.02 0.05 B( y, B( 0.05 3. Strangeness- D B( 0 0 0 Dependent Net - - - 1 1 1 - 0.5 0 0 0 D D 4 D Baryon? y 1 4 0.5 4 2 y y 1 2 2 0 1 0 0 j (rad) D (rad) ) D j D j r a d ( ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV ALICE Pb-Pb ALICE Pb-Pb s s = 2.76 TeV = 2.76 TeV NN NN NN NN NN NN p ± p ± 0.2< p <2 GeV/ c 70-90% ± £ £ £ £ 0.2 p 2 GeV/ c K 60-90% 0.5 p 2.5 GeV/ c p p 40-80% T T T 0.15 0.06 0.06 ) -1 ) (rad ) j ) 0.04 0.1 j D 0.04 D y, j y, D D D 0.02 B( 0.05 y, B( 0.02 D B( 0 0 0 - - 1 - 1 1 - 0.5 0 0 0 D 4 D D y 1 2 4 0.5 4 y y 0 2 2 1 1 0 0 j (rad) D j (rad) j a d ) D D ( r Increasing Mass ( MeV) 139 496 938
B(Δy) Projections & Widths 12 π ± K ± p(p) π ± K ± p(p) 0.02 - - - this thesis 0 5 % 0 10 % 0 20 % p this thesis - p - - 0 5 % 0 10 % p 0 20 % p K p p K 0.6 - - - Pb-Pb s = 2.76 TeV 0.1 - - - 30 40 % 30 40 % 20 40 % Pb-Pb s = 2.76 TeV 30 40 % 30 40 % 20 40 % NN 0.02 NN p p p p - - - - - - 70 90 % 60 90 % 40 80 % 70 90 % 60 90 % 40 80 % 0.4 π ± 0.4 0.05 0.01 0.05 0.01 0.2 0.2 0 0 0 0 0 0 - - - 0 2 4 0 2 4 0 2 4 1 0 1 1 0 1 1 0 1 - - - 0 10 % 0 10 % 0 20 % p - - - p 0 10 % 0 10 % Kp 0 20 % K Kp KK K KK 0.4 0.03 0.6 - - - 30 40 % 30 40 % 20 40 % - - - 30 40 % 30 40 % 20 40 % 0.4 0.15 - - - - - - 60 90 % 60 90 % 40 80 % ) 60 90 % 60 90 % 40 80 % -1 0.04 0.3 ) (rad y) 0.02 0.4 0.1 K ± D 0.2 B ( 0.2 j 0.02 D 0.01 0.2 0.05 B( 0.1 0 0 0 0 0 0 - - - 1 0 1 1 0 1 1 0 1 0 2 4 0 2 4 0 2 4 - - - 0 20 % 0 20 % 0 20 % p p - - - p p 0 20 % pK 0 20 % 0 20 % pK pp pp 0.4 - - - 0.15 0.15 0.1 0.1 20 40 % 20 40 % 20 40 % - - - 20 40 % 20 40 % 20 40 % 0.3 - - - - - - 40 80 % 40 80 % 40 80 % 40 80 % 40 80 % 40 80 % 0.3 0.1 0.1 0.2 0.2 0.05 0.05 p(p) 0.1 0.05 0.05 0.1 0 0 0 0 0 0 - - - 1 0 1 1 0 1 1 0 1 0 2 4 0 2 4 0 2 4 D D j y Δɸ (rad) (rad) Δy
BF Widths and Integrals 13 0.2 < p T ( π ± , K ± ) < 2.0 GeV/ c ALICE Pb-Pb s = 2.76 TeV 1 NN 0.5 < p T ( p(p) ) < 2.5 GeV/ c ± p ± - p ± - p ± - p ± K p( p ) ± ± ± ± p ± - - - K K K p( p ) K ± p ± - - - p( p ) K p( p ) p( p ) p( p ) 0.8 y D s 0.6 STAR PRC 82, 024905 (2010) 0.4 0 20 40 60 80 Au-Au @ 200 GeV 1.5 0.2 < p T < 0.6 GeV/ c j D s 1 ALICE, PRC 88, 044910 (2013) 0 20 40 60 80 0.6 0.4 B Y 0.2 0 0 20 40 60 80 Centrality (%)
Mo Motiva vation: 14 h π k p Λ ✓ h Q ✓ ✓ ✓ Q π ✓ ✓ ✓ k Q S ✓ ✓ ✓ P Q B B S Λ Work in Progress Run II : Pb+Pb @ 5020 GeV Run I : Pb+Pb @ 2760 GeV
Re Resu sults: s: R2 R2 15 0-10% Same Opposite Baryon/Strange Baryon/Strange ΛΛ + $ Λ $ Λ$ Λ Λ 30-40% C 2 ( x 1 , x 2 ) R 2 ( x 1 , x 2 ) = ρ 1 ( x 1 ) ρ 1 ( x 2 ) Ref: Eur.Phys.J. C77 (2017) 569 p+p @ √s =7 TeV 60-80%
Re Resu sults: s: B 16 Two Wave quark Production??? Radial Flow effect???
At At Lu Lund: Λ# 1. Make a multiplicity dependent RT & SO analysis for analysis Λ and make a connection Between Balance Function & Per Trigger Yield analysis 2. Extend Jonatan’s study of 𝚶 𝚶 correlation to Ω Ω Correlation 3. Grid MC: for Rope Tune CD based CR 4. Pythia ANTAGYR Study and Make a comparison with QCD- QGP(EPOS) approach to regular PYTHIA MPI model(Lund string model), Strange (Rope Hadronization framework/ Flavour Ropes ) and Flow(Rope Hadronization framework/ String shoving) 5. … Thank You
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