Dihadron azimuthal correlations in Au$+$Au collisions at $\sqrt{s_{NN}}=$ 200 GeV

The collaboration
Phys.Rev.C 78 (2008) 014901, 2008.

Abstract (data abstract)
BNL-RHIC. Azimuthal angle ($\Delta\phi$) correlations are presented for a broad range of transverse momentum ($0.4 < p_{\rm T} < 10$~GeV/$c$) and centrality (0-92%) selections for charged hadrons from di-jets in Au+Au collisions at $\sqrt{s_{\rm{NN}}}$ = 200 GeV. With increasing $p_{\rm T}$, the away-side $\Delta\phi$ distribution evolves from a broad and relatively flat shape to a concave shape, then to a convex shape. Comparisons to $p+p$ data suggest that the away-side distribution can be divided into a partially suppressed "head" region centered at $\Delta\phi\sim\pi$, and an enhanced "shoulder" region centered at $\Delta\phi\sim \pi\pm 1.1$. The $p_{\rm T}$ spectrum for the associated hadrons in the head region softens toward central collisions. The spectral slope for the shoulder region is independent of centrality and trigger $p_{\rm T}$. The properties of the near-side distributions are also modified relative to those in $p+p$ collisions, reflected by the broadening of the jet shape in $\Delta\phi$ and $\Delta\eta$, and an enhancement of the per-trigger yield. However, these modifications seem to be limited to $p_{\rm T}\lesssim4$ GeV/$c$, above which both the hadron pair shape and per-trigger yield become similar to $p+p$ collisions. These observations suggest that both the away- and near-side distributions contain a jet fragmentation component which dominates for $p_{\rm T}\gtrsim5$ GeV and a medium-induced component which is important for $p_{\rm T}\lesssim4$ GeV/$c$. We also quantify the role of jets at intermediate and low $p_{\rm T}$ through the yield of jet-induced pairs in comparison to binary scaled $p+p$ pair yield. The yield of jet-induced pairs is suppressed at high pair proxy energy (sum of the $p_{\rm T}$ magnitudes of the two hadrons) and is enhanced at low pair proxy energy. The former is consistent with jet quenching; the latter is consistent with the enhancement of soft hadron pairs due to transport of lost energy to lower $p_{\rm T}$.

• #### Figure 6, pp, part 2/2

10.17182/hepdata.96764.v2/t1

Per-trigger yield versus $\Delta\phi$ for various trigger and partner $p_T$ ($p^a_T \otimes p^b_T$), arranged by increasing pair proxy energy (sum...

• #### Figure 6, pp, part 1/2

10.17182/hepdata.96764.v2/t2

Per-trigger yield versus $\Delta\phi$ for various trigger and partner $p_T$ ($p^a_T \otimes p^b_T$), arranged by increasing pair proxy energy (sum...

• #### Figure 6, AuAu, part 1/2

10.17182/hepdata.96764.v2/t3

Per-trigger yield versus $\Delta\phi$ for various trigger and partner $p_T$ ($p^a_T \otimes p^b_T$), arranged by increasing pair proxy energy (sum...

• #### Figure 6, AuAu, part 2/2

10.17182/hepdata.96764.v2/t4

Per-trigger yield versus $\Delta\phi$ for various trigger and partner $p_T$ ($p^a_T \otimes p^b_T$), arranged by increasing pair proxy energy (sum...

• #### Figure 7, p + p collisions

10.17182/hepdata.96764.v2/t5

RHS versus $p^b_T$ for p + p collisions for four trigger selections.

• #### Figure 7, Au + Au collisions

10.17182/hepdata.96764.v2/t6

RHS versus $p^b_T$ for Au + Au collisions for four trigger selections.

• #### Figure 8

10.17182/hepdata.96764.v2/t7

RHS versus $N_{part}$ for 2-3 $\otimes$ 2-3 GeV/$c$. Shaded bars (brackets) represent $p_T$ -correlated uncertainties due to elliptic flow (ZYAM...

• #### Figure 9

10.17182/hepdata.96764.v2/t8

Per-trigger yield $\Delta\phi$ distribution and corresponding fits for 2-3 $\otimes$ 2-3 GeV/c in 0-5% Au+Au collisions.

• #### Figure 10

10.17182/hepdata.96764.v2/t9

a) D versus centrality from FIT 1 and FIT2 for 2 - 3 GeV/$c$ bin. The error bars are the...

• #### Figure 11, FIT1, 2-3

10.17182/hepdata.96764.v2/t10

Values of D determined from FIT1 as function of partner $p_T$ for 2-3 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 11, FIT1, 3-4

10.17182/hepdata.96764.v2/t11

Values of D determined from FIT1 as function of partner $p_T$ for 3-4 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 11, FIT1, 4-5

10.17182/hepdata.96764.v2/t12

Values of D determined from FIT1 as function of partner $p_T$ for 4-5 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 11, FIT2, 2-3

10.17182/hepdata.96764.v2/t13

Values of D determined from FIT2 as function of partner $p_T$ for 2-3 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 11, FIT2, 3-4

10.17182/hepdata.96764.v2/t14

Values of D determined from FIT2 as function of partner $p_T$ for 3-4 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 11, FIT2, 4-5

10.17182/hepdata.96764.v2/t15

Values of D determined from FIT2 as function of partner $p_T$ for 4-5 GeV/c $p_T$ range in 0-20% Au+Au.

• #### Figure 12, 0-20%, head

10.17182/hepdata.96764.v2/t16

Per-trigger yield as function of partner $p_T$ for the HR region for the 0-20% Au + Au collisions. Results for...

• #### Figure 12, 20-40%, head

10.17182/hepdata.96764.v2/t17

Per-trigger yield as function of partner $p_T$ for the HR region for the 20-40% Au + Au collisions. Results for...

• #### Figure 12, 40-60%, head

10.17182/hepdata.96764.v2/t18

Per-trigger yield as function of partner $p_T$ for the HR region for the 40-60% Au + Au collisions. Results for...

• #### Figure 12, 60-92%, head

10.17182/hepdata.96764.v2/t19

Per-trigger yield as function of partner $p_T$ for the HR region for the 60-92% Au + Au collisions. Results for...

• #### Figure 12, p + p, head

10.17182/hepdata.96764.v2/t20

Per-trigger yield as function of partner $p_T$ for the HR region for the p + p collisions. Results for four...

• #### Figure 12, 0-20%, shoulder

10.17182/hepdata.96764.v2/t21

Per-trigger yield as function of partner $p_T$ for the SR region for the 0-20% Au + Au collisions. Results for...

• #### Figure 12, 20-40%, shoulder

10.17182/hepdata.96764.v2/t22

Per-trigger yield as function of partner $p_T$ for the SR region for the 20-40% Au + Au collisions. Results for...

• #### Figure 12, 40-60%, shoulder

10.17182/hepdata.96764.v2/t23

Per-trigger yield as function of partner $p_T$ for the SR region for the 40-60% Au + Au collisions. Results for...

• #### Figure 12, 60-92%, shoulder

10.17182/hepdata.96764.v2/t24

Per-trigger yield as function of partner $p_T$ for the SR region for the 60-92% Au + Au collisions. Results for...

• #### Figure 12, p + p, shoulder

10.17182/hepdata.96764.v2/t25

Per-trigger yield as function of partner $p_T$ for the SR region for the p + p collisions. Results for four...

• #### Figure 16, Au + Au

10.17182/hepdata.96764.v2/t26

Near-side Gaussian widths versus partner $p_T$ for four trigger $p_T$ ranges for 0-20 % Au + Au.

• #### Figure 16, p + p

10.17182/hepdata.96764.v2/t27

Near-side Gaussian widths versus partner $p_T$ for four trigger $p_T$ ranges for 0-20 % p + p.

• #### Figure 17

10.17182/hepdata.96764.v2/t28

Near-side Gaussian widths versus $N_{part}$ for five successively increasing $p^a_T$ $\otimes$ $p^b_T$. The most left point in each panel represents...

• #### Figure 18, p + p, near-side

10.17182/hepdata.96764.v2/t29

Near-side yield in $\lvert \Delta\phi \rvert$ < $\pi$/3 versus partner $p_T$ for four trigger $p_T$ selections for 0-20% p +...

• #### Figure 18, 0-20%, near-side

10.17182/hepdata.96764.v2/t30

Near-side yield in $\lvert \Delta\phi \rvert$ < $\pi$/3 versus partner $p_T$ for four trigger $p_T$ selections for 0-20% Au +...

• #### Figure 18 Supplemental, 20-40%, near-side

10.17182/hepdata.96764.v2/t31

Near-side yield in $\lvert \Delta\phi \rvert$ < $\pi$/3 versus partner $p_T$ for four trigger $p_T$ selections for 0-20% Au +...

• #### Figure 18 Supplemental, 40-60%, near-side

10.17182/hepdata.96764.v2/t32

Near-side yield in $\lvert \Delta\phi \rvert$ < $\pi$/3 versus partner $p_T$ for four trigger $p_T$ selections for 0-20% Au +...

• #### Figure 18 Supplemental, 60-92%, near-side

10.17182/hepdata.96764.v2/t33

Near-side yield in $\lvert \Delta\phi \rvert$ < $\pi$/3 versus partner $p_T$ for four trigger $p_T$ selections for 0-20% Au +...

• #### Figure 23, AuAu

10.17182/hepdata.96764.v2/t34

Per-trigger yield versus $\Delta\eta$ for 0-20% central Au + Au collisions. Results are shown for four $p^a_T \otimes p^b_T$ selections...

• #### Figure 23, pp

10.17182/hepdata.96764.v2/t35

Per-trigger yield versus $\Delta\eta$ for 0-20% central p + p collisions. Results are shown for four $p^a_T \otimes p^b_T$ selections...

• #### Figure 24, eta

10.17182/hepdata.96764.v2/t36

The projection of 2-D per-trigger yield in $\lvert \Delta\eta \rvert$ < 0.7 $\otimes$ $\lvert \Delta\phi \rvert$ < 0.7 and 0-20%...

• #### Figure 24, phi

10.17182/hepdata.96764.v2/t37

The projection of 2-D per-trigger yield in $\lvert \Delta\eta \rvert$ < 0.7 $\otimes$ $\lvert \Delta\phi \rvert$ < 0.7 and 0-20%...

• #### Figure 25, head Au+Au

10.17182/hepdata.96764.v2/t38

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the head region for Au...

• #### Figure 25, away-side shoulder Au+Au

10.17182/hepdata.96764.v2/t39

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the away-side shoulder region for...

• #### Figure 25, near-side Au+Au

10.17182/hepdata.96764.v2/t40

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the near-side region for Au...

• #### Figure 25, head p+p

10.17182/hepdata.96764.v2/t41

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the head region for p...

• #### Figure 25, away-side shoulder p+p

10.17182/hepdata.96764.v2/t42

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the away-side shoulder region for...

• #### Figure 25, near-side p+p

10.17182/hepdata.96764.v2/t43

Truncated mean $p_T$, $\langle p_T \rangle$, in 1 <pbT < 5 GeV/c versus centrality for the near-side region for p...

• #### Figure 26, 3-4 GeV/c Au+Au

10.17182/hepdata.96764.v2/t44

Truncated mean $p_T$, $\langle p_T \rangle$, calculated for five partner pT ranges in the HR. Results for triggers in 3-4...

• #### Figure 26, 4-5 GeV/c Au+Au

10.17182/hepdata.96764.v2/t45

Truncated mean $p_T$, $\langle p_T \rangle$, calculated for five partner pT ranges in the HR. Results for triggers in 4-5...

• #### Figure 26, 3-4 GeV/c p+p

10.17182/hepdata.96764.v2/t46

Truncated mean $p_T$, $\langle p_T \rangle$, calculated for five partner pT ranges in the HR. Results for triggers in 3-4...

• #### Figure 26, 4-5 GeV/c p+p

10.17182/hepdata.96764.v2/t47

Truncated mean $p_T$, $\langle p_T \rangle$, calculated for five partner pT ranges in the HR. Results for triggers in 4-5...

• #### Figure 28 0-20% Au+Au

10.17182/hepdata.96764.v2/t48

The near-side pair suppression factor $J_{AA}$ in 0-20% Au + Au collisions as function of $p^b_T$ for various ranges of...

• #### Figure 30, 20-40%

10.17182/hepdata.96764.v2/t49

The near-side $J_{AA}$ as function of $p^b_T$ and $p^{sum}_T$ for four $p^a_T$ bins and three centrality bins. Data for 20-40%.

• #### Figure 30, 40-60%

10.17182/hepdata.96764.v2/t50

The near-side $J_{AA}$ as function of $p^b_T$ and $p^{sum}_T$ for four $p^a_T$ bins and three centrality bins. Data for 40-60%.

• #### Figure 30, 60-92%

10.17182/hepdata.96764.v2/t51

The near-side $J_{AA}$ as function of $p^b_T$ and $p^{sum}_T$ for four $p^a_T$ bins and three centrality bins. Data for 60-92%.

• #### Figure 31, 0-20%, away-side

10.17182/hepdata.96764.v2/t52

The pair suppression factor $J_{AA}$ for the away-side HR in 0-20% Au + Au collisions as function of $p_b^T$ for...

• #### Figure 31, 20-40%, away-side

10.17182/hepdata.96764.v2/t53

The pair suppression factor $J_{AA}$ for the away-side HR in 20-40% Au + Au collisions as function of $p_b^T$ for...

• #### Figure 31, 40-60%, away-side

10.17182/hepdata.96764.v2/t54

The pair suppression factor $J_{AA}$ for the away-side HR in 40-60% Au + Au collisions as function of $p_b^T$ for...

• #### Figure 31, 60-92%, away-side

10.17182/hepdata.96764.v2/t55

The pair suppression factor $J_{AA}$ for the away-side HR in 60-92% Au + Au collisions as function of $p_b^T$ for...

• #### Figure 36, Au + Au

10.17182/hepdata.96764.v2/t56

Per-trigger yield versus $\Delta\phi$ for successively increasing trigger and partner $p_T$ ($p^a_T \otimes p^b_T$) in 0-20 % Au + Au...

• #### Figure 37, Au + Au

10.17182/hepdata.96764.v2/t57

Per-trigger yield versus $\Delta\phi$ for successively increasing trigger and partner $p_T$ ($p^a_T \otimes p^b_T$) in 20-40 % Au + Au...

• #### Supplemental, 40-60% Au + Au

10.17182/hepdata.96764.v2/t58

Per-trigger yield versus $\Delta\phi$ for successively increasing trigger and partner $p_T$ ($p^a_T \otimes p^b_T$) in 40-60 % Au + Au...

• #### Figure 38, Au + Au

10.17182/hepdata.96764.v2/t59

Per-trigger yield versus $\Delta\phi$ for successively increasing trigger and partner $p_T$ ($p^a_T \otimes p^b_T$) in 60-92 % Au + Au...

• #### Figure 36-38, p + p

10.17182/hepdata.96764.v2/t60

Per-trigger yield versus $\Delta\phi$ for successively increasing trigger and partner $p_T$ ($p^a_T \otimes p^b_T$) in p + p collisions.

Version 2 modifications: Multiple corrections of plots