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A-58 - Coalescence and thermal production models bound dangerous strangelet yield near 1e-46 per collision, peaking below AGS energies rather than at RHIC

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Properties9
type
argument
id
A-58
statement
Both empirically calibrated production mechanisms make a dangerous strangelet hopeless at RHIC: the AGS-fitted coalescence model (penalty 0.02 per added baryon, 0.2 per unit strangeness, transition to a single quark bag generously taken at unit probability) yields ~1e-46 per collision for an A=20, Z=-1, S=22 strangelet, i.e. p ≈ 2e-35 over RHIC's lifetime; the thermal model (T = 140 MeV, mu_B = 540 MeV at AGS) gives ~2e-27 per central collision even for a benign A=20, Z=+2, S=16 strangelet, with negative-charge yields far smaller — and both models predict production falls as collision energy rises, so the optimum energy lies below the AGS, while the speculative strangeness-distillation mechanism is contradicted by the observed rapid adiabatic expansion and the failure of CERN heavy-ion experiments to see strangelets despite probable QGP formation.
source
S-3 - Busza, Jaffe, Sandweiss, Wilczek- Review of Speculative Disaster Scenarios at RHIC
locator
§V.B (refs [26]-[29])
affects_observations
affects_hypotheses
status
approved
reason_if_not_false
checked

Reasoning:

  1. Qualitative core, before any model: strangelets are cold (bound by tens of MeV) while collisions are hot (≥100 MeV if equilibrated) — condensing one is like making an ice cube in a furnace; s-sbar pairs concentrate at central rapidity while baryon chemical potential peaks in the fragmentation regions, so the two required inputs live in different places; more negative charge means more s quarks, and larger (more stable) strangelets are harder to make — production difficulty and stability requirements pull in opposite directions.
  2. Coalescence numbers: deuteron yield ~1 per collision; each added baryon costs 0.02 (AGS fit), each strangeness unit 0.2 (possibly 0.03); A=20, Z=-1, S=22 → ~1e-46 per collision → p ≈ 2e-35 for 2e11 collisions. Coalescence factors decrease with energy (produced particles are more energetic, less likely to sit in the narrow relative-momentum window), confirmed dramatically from Bevalac → AGS → CERN; the most favorable energy is below the AGS.
  3. Thermal numbers: Braun-Munzinger-Stachel AGS fits give 2e-27 per central collision for A=20, Z=2, S=16 (~1 per 2e27 collisions using centrality 0.2), before the much larger negative-charge penalty; rising T and falling mu_B make this drop quickly with energy.
  4. Distillation, the only mechanism claimed to favor colliders: requires a baryon-rich QGP cooling slowly by surface evaporation; contradicted by evidence for rapid, approximately adiabatic bulk expansion, by falling baryon density at central rapidity at RHIC, and by null CERN strangelet searches despite substantial evidence a QGP forms there. If distillation worked, the CERN nulls argue against strangelets themselves.

Step 6 verdict

Verdict: approved (checked). Traced the coalescence arithmetic: ~1 deuteron/collision x 0.02^19 (added baryons) ~ 5e-33, x 0.2^22 (strangeness) ~ 4e-16 gives ~2e-48, consistent with the quoted ~1e-46 within the model’s stated penalty-range slack (0.2 vs 0.03 per strangeness unit spans orders); x 2e11 collisions ~ 1e-35 as claimed. The thermal-model figure and the energy-scaling direction (coalescence penalties worsen with energy, confirmed Bevalac → AGS → CERN; thermal T rising / mu_B falling) follow from the calibrated-model premises. The distillation rebuttal is a separate empirical modus tollens (rapid adiabatic expansion + null CERN strangelet searches despite probable QGP), valid as evidence-against. Conclusion - dangerous production hopeless at RHIC, optimum energy below AGS - follows conditional on the models; model truth is priced downstream.

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