Discussion Overview
The discussion centers around the interpretation of the beam momentum of 158 A*GeV/c in lead-lead (Pb + Pb) collisions at the SPS accelerator at CERN. Participants explore the implications of this momentum in the context of nuclear physics, particularly regarding the energy per nucleon and the historical context of SPS energy levels.
Discussion Character
- Technical explanation
- Debate/contested
- Historical
Main Points Raised
- One participant inquires whether the momentum of 158 A*GeV/c should be divided by the nuclear mass number A to find the momentum of individual nucleons.
- Another participant asserts that 158 GeV/c refers to the energy per nucleon.
- A subsequent post questions if the SPS can achieve 400 GeV, suggesting this is also per nucleon.
- One participant explains that the radius of curvature of a charged particle's orbit remains consistent whether alone or within a nucleus, relating this to the SPS's capability to accelerate protons and nuclei.
- Another participant challenges the 400 GeV figure, stating that the SPS now provides proton beams at 450 GeV, referencing the LHC's energy levels for lead and proton collisions.
- A participant agrees with the updated energy figure but notes that the experiment discussed in the article occurred in 2000, when the SPS likely operated at 400 GeV.
Areas of Agreement / Disagreement
Participants express differing views on the current and historical energy levels of the SPS, with some asserting that the SPS has been upgraded to 450 GeV while others maintain that the article refers to an earlier operational state at 400 GeV. There is no consensus on the implications of the beam momentum in relation to individual nucleons.
Contextual Notes
The discussion reflects uncertainty regarding the historical context of SPS energy levels and the implications of beam momentum per nucleon. There are unresolved questions about the accuracy of energy figures and their relevance to the specific experiment discussed.