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qmri.constants

Physical constants for MRI.

This module provides:

  • Gyromagnetic ratios
  • Tissue relaxation times at various field strengths
  • Blood-brain partition coefficients
  • Water diffusivity

GAMMA_H module-attribute 

GAMMA_H: float = 42577478.92

Gyromagnetic ratio for ¹H (proton) in Hz/T.

GAMMA_C13 module-attribute 

GAMMA_C13: float = 10708400.0

Gyromagnetic ratio for ¹³C in Hz/T.

GAMMA_F19 module-attribute 

GAMMA_F19: float = 40052000.0

Gyromagnetic ratio for ¹⁹F in Hz/T.

GAMMA_P31 module-attribute 

GAMMA_P31: float = 17235000.0

Gyromagnetic ratio for ³¹P in Hz/T.

GAMMA_NA23 module-attribute 

GAMMA_NA23: float = 11262000.0

Gyromagnetic ratio for ²³Na in Hz/T.

LAMBDA_BRAIN module-attribute 

LAMBDA_BRAIN: float = 0.9

Blood-brain partition coefficient in ml/g.

D_WATER_37C module-attribute 

D_WATER_37C: float = 0.003

Water diffusivity at 37°C in mm²/s.

__all__ module-attribute 

__all__ = [
    "GAMMA_H",
    "GAMMA_C13",
    "GAMMA_F19",
    "GAMMA_P31",
    "GAMMA_NA23",
    "LAMBDA_BRAIN",
    "D_WATER_37C",
]