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Universal flow-driven conical emission in ultrarelativistic heavy-ion collisions
Barbara Betz1, Jorge Noronha, Giorgio Torrieri
1Department of Physics, Columbia University, New York, 10027, USA.
Physical Review Letters
|January 15, 2011
Summary
The double-peak structure in heavy-ion collisions may not indicate a Mach cone. This pattern can emerge from averaging jet events in an expanding background, offering new avenues for experimental testing.
Area of Science:
- Nuclear Physics
- High-Energy Physics
- Quantum Chromodynamics
Background:
- The double-peak structure in soft-hard hadron correlations is often attributed to Mach cones from supersonic jets in ultrarelativistic heavy-ion collisions.
- Mach cones are theoretical constructs representing shock waves generated by energetic particles traversing a medium.
Purpose of the Study:
- To investigate alternative explanations for the double-peak structure in soft-hard hadron correlations.
- To determine if the observed structure can arise from phenomena other than Mach cones.
Main Methods:
- Theoretical modeling of jet interactions within a transversally expanding medium.
- Analysis of soft-hard hadron correlations under various background conditions.
- Comparison of jet-induced yields independent of specific energy-momentum deposition details.
Main Results:
- The double-peak structure can be reproduced by averaging over multiple jet events within a transversally expanding background.
- The jet-induced away-side yield is found to be independent of plasma energy-momentum deposition, jet velocity, and system size.
- This finding challenges the exclusive interpretation of the double-peak structure as a signature of Mach cones.
Conclusions:
- The observed double-peak structure in soft-hard hadron correlations does not solely signify a Mach cone.
- Averaging effects in a transversally expanding medium provide a viable alternative explanation.
- Experimental verification can be achieved by comparing heavy-flavor and light-flavor jet-induced correlations.
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