αclusters and collective flow in ultrarelativistic carbon–heavy-nucleus collisions

Abstract

We investigate ultrarelativistic collisions of the 12 C nucleus with heavy targets and show that the harmonic flow measures based on ratios of cumulant moments are particularly suited to study the intrinsic deformation of the 12 C wave function. That way one can probe the expected α clusterization in the ground state, which leads to large initial triangularity in the shape of the fireball in the transverse plane. We show that the clusterization effect results in very characteristic behavior of the ratios of the cumulant moments as functions of the number of participant nucleons, both for the elliptic and triangular deformations. Thus the experimental event-by-event studies of harmonic flow in ultrarelativistic light-heavy collisions may offer a new window to look at the ground-state structure of light nuclei.

Nuclear cluster structure effect on elliptic and triangular flows in heavy-ion collisions

“…In Ref. [33,34], the collective flow ratio between the flow from four-particle cumulant and the flow from two-particle cumulant is proposed as a signature of α-clustered 12 C. In this work another observable will be presented to distinguish the geometry pattern of 12 C. Figure 5 presents the second and third order participant eccentricity coefficients, namely ǫ 2 {P P } and ǫ 3 {P P }, as a function of N track in 12 C + 197 Au collisions at √ s N N = 200 GeV and 10 GeV in the AMPT model with different configuration pattern of 12 C. ǫ 2 {P P } slightly increases for the Chain structure pattern of 12 C and decreases for the other patterns, with the increasing of N track . So does for ǫ 3 {P P }.…”

“…As discussed in Ref. [33], κ n depends on the details of collision system and model, the linearity of Eq. (6) allows for model-independent studies for collective flow.…”

“…It was proposed that the intrinsic geometry of light nuclei can be studied in heavy-ion collisions by exploring elliptic and triangular flow formed in the collisions [33,34]. In these works the carbon is considered with 3-α and collides against a heavy nucleus at very high energies.…”

Clustering structure effect on Hanbury-Brown–Twiss correlation in $$^{12}\hbox {C} {+^{197}}\hbox {Au}$$ collisions at 200 GeV

“…where r and φ are the polar coordinate positions in transverse plane of participant nucleons. Table III presents the final eccentricity estimated by 2R 2 s,2 /R 2 s,0 and the initial eccentricity for different configurations of 12 C. It is expected that the second-order eccentricity takes the largest value for chain structure and the third-order eccentricity is larger for triangle structure than that for other cases as |R 2 s(o),3 | listed in [20][21][22][23]. Further, the system scan experiments around 12 C may provide the platform to examine if there are α clusters in the carbon nuclei and to distinguish the structure by comparing the HBT correlation and collective flow between 12 C+A collisions and other colliding systems.…”

Elliptic flow in ultrarelativistic collisions with light polarized nuclei

“…Early studies of collectivity in small systems were carried out in [8][9][10][11][12], followed by investigations of triangularity in 3 He-A collisions [13][14][15], or studies of the α clusterization effects in 12 C-A collisions [16][17][18][19] and other light clustered nuclei [20][21][22].…”