Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8186913 | Physics Letters B | 2018 | 6 Pages |
Abstract
In non-central relativistic heavy ion collisions, the created matter possesses a large initial orbital angular momentum. Particles produced in the collisions could be polarized globally in the direction of the orbital angular momentum due to spin-orbit coupling. Recently, the STAR experiment has presented polarization signals for Î hyperons and possible spin alignment signals for Ï mesons. Here we discuss the effects of finite coverage on these observables. The results from a multi-phase transport and a toy model both indicate that a pseudorapidity coverage narrower than |η|<â¼1 will generate a larger value for the extracted Ï-meson Ï00 parameter; thus a finite coverage can lead to an artificial deviation of Ï00 from 1/3. We also show that a finite η and pT coverage affect the extracted pH parameter for Î hyperons when the real pH value is non-zero. Therefore proper corrections are necessary to reliably quantify the global polarization with experimental observables.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Nuclear and High Energy Physics
Authors
Shaowei Lan, Zi-Wei Lin, Shusu Shi, Xu Sun,