Physics
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Compton Scattering Calculator.
Calculate Compton wavelength shift and scattered wavelength for a photon.
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Results update as you type.
Results update automatically as you type.
This page applies only the stated idealized equation and explicit inputs; verify specialized engineering, medical, or safety decisions against applicable standards.
Use Cases
Physics homework and lab verification
Students and educators can quickly verify Compton scattering calculations for assignments or lab experiments, ensuring accurate wavelength shifts.
Example: Check the shift for a 0.01 nm X-ray scattered at 90°.
Research and experimental planning
Researchers can estimate the expected wavelength shift for given scattering angles to design experiments or interpret data in X-ray and gamma-ray studies.
Example: Plan a scattering experiment with 0.02 nm photons at 60°.
Frequently Asked Questions
- What does the Compton scattering calculator compute?
- It computes the Compton wavelength shift (Δλ) and the scattered wavelength (λ') for a photon given its incident wavelength and scattering angle. The shift is based on the Compton formula Δλ = h/(m_e c)(1 - cosθ).
- What units are used for wavelength and angle?
- Incident wavelength is entered in meters (m), and scattering angle is entered in degrees (°). The calculator outputs the wavelength shift and scattered wavelength in meters.
- Can I use this calculator for any photon energy?
- Yes, as long as you provide the incident wavelength in meters. The calculator applies the Compton scattering formula, which is valid for photons scattering off free electrons, typically X-rays or gamma rays.
Tips & Common Mistakes
Tips
- Ensure the incident wavelength is in meters; convert from nanometers by multiplying by 1e-9.
- The scattering angle is measured between the incident and scattered photon directions, typically from 0° to 180°.
- The Compton shift is independent of the incident wavelength; it depends only on the scattering angle.
- For small angles, the shift is minimal; for 180° (backscattering), the shift is maximum.
Common Mistakes to Avoid
- Forgetting to convert wavelength from nanometers to meters before entering it.
- Using degrees instead of radians in manual calculations, but the calculator handles degrees automatically.
- Assuming the scattered wavelength is the same as the incident wavelength; the shift is always positive for non-zero angles.
Last updated: August 13, 2026