Comparison of Resonance Models
Today is Tuesday, July 01, 2025, 10:05 PM PDT.
### IntroductionIn particle physics, resonances are excited states of particles observed as peaks in scattering experiments. This page compares two models for predicting the masses of two specific resonances: the Delta resonance (Ξ(1232)) and the N(1440) resonance (Roper resonance).
### Proton Radius CalculationThe quantized superfluid model calculates the proton radius using:
\[ R_p = \frac{\hbar n}{m_p c} = 4 \times \frac{\hbar}{m_p c} \]
With \( \hbar c = 197.32698 \, \text{MeV·fm} \) and \( m_p c^2 = 938.272 \, \text{MeV} \), this yields:
\[ R_p = 4 \times \frac{197.32698}{938.272} \approx 0.8412 \, \text{fm} \]
The measured proton charge radius is approximately \( 0.841 \, \text{fm} \), showing excellent agreement.
### Quantized Superfluid ModelThis model views the proton as a quantized superfluid with a characteristic speed \( v = c \) (speed of light) and a quantum number \( n = 4 \). Resonance masses are calculated as:
\[ m_n c^2 = \frac{n}{4} m_p c^2 \]
For the Delta resonance (\( n = 5 \)) and Roper resonance (\( n = 6 \)), masses are derived from the proton mass \( m_p c^2 = 938.272 \, \text{MeV} \).
### Accepted Quark ModelThe quark model describes baryons as three-quark systems. Resonance masses are predicted using parameters like constituent quark masses and coupling constants, fitted to experimental data. Here, we use typical literature values for comparison.
### Comparison TableResonance | Measured Mass (MeV) | Superfluid Model Mass (MeV) | Quark Model Mass (MeV) | Superfluid % Error | Quark % Error |
---|---|---|---|---|---|
Delta (n=5) | 1232 | 1232 | 0.00 | ||
Roper (n=6) | 1440 | 1400 |
The quantized superfluid model predicts the proton radius with high accuracy without tuning parameters. It also approximates the Delta and Roper resonance masses with percent errors of approximately -4.8% and -2.3%, respectively.
The quark model, however, relies on parameter fitting. For instance, the Delta mass is often fitted to match the measured 1232 MeV (0% error), but this leads to a larger error for the Roper resonance (approximately -2.8% here).
The superfluid model's ability to predict these values without adjustments suggests it may capture fundamental aspects of proton structure and resonance behavior, offering a compelling alternative to the parameter-dependent quark model.
I’ve had this model for a few years and just realized it predicts the resonances more accurately and simply than QCD.
ReplyDeleteAnd some of the error is probably due to error in the constants.
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