Core-corona separation in ultrarelativistic heavy ion collisions

Area of Science:

• Nuclear Physics
• High Energy Physics
• Particle Physics

Background:

• High energy nuclear collisions are studied to understand matter under extreme conditions.
• The collision zone's structure influences experimental observables.
• Distinguishing between central and peripheral contributions is crucial for accurate interpretation.

Purpose of the Study:

• To introduce a method for separating the 'core' and 'corona' contributions in nuclear collisions.
• To quantify the relative importance of the 'corona' in different collision centralities.
• To analyze the impact of this separation on interpreting experimental results.

Main Methods:

• Utilizing simple geometrical considerations to define core and corona regions.
• Developing calculation methods to disentangle core and corona contributions.
• Analyzing collision data from Relativistic Heavy Ion Collider (RHIC) and Super Proton Synchrotron (SPS).

Main Results:

• The collision zone can be divided into a high-density 'core' and a lower-density 'corona'.
• The corona contribution is small but non-negligible in central collisions.
• The corona's importance increases significantly as collisions become less central (larger impact parameters).

Conclusions:

• The proposed separation method provides a more nuanced understanding of nuclear collisions.
• Experimental results from RHIC and SPS should account for the corona's contribution, especially in non-central collisions.
• This work refines models of particle production in high energy nuclear interactions.