1. What is the Absorbed Dose Formula?

The absorbed dose formula calculates the energy absorbed per unit mass in a medium from ionizing radiation. It's a fundamental concept in treatment planning systems (TPS) for radiation therapy.

2. How Does the Calculator Work?

The calculator uses the absorbed dose equation:

Where:

• \( D \) — Absorbed dose (Gy)
• \( \mu_{en} / \rho \) — Mass energy absorption coefficient (m²/kg)
• \( \Phi \) — Fluence (1/m²)
• \( E \) — Energy (J)

Explanation: The equation calculates the energy absorbed per unit mass by considering the material's absorption properties, the number of particles, and their energy.

3. Importance of Absorbed Dose Calculation

Details: Accurate dose calculation is crucial for radiation therapy treatment planning, ensuring sufficient dose to the target while sparing healthy tissues.

4. Using the Calculator

Tips: Enter the mass energy absorption coefficient in m²/kg, fluence in 1/m², and energy in Joules. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between absorbed dose and equivalent dose?
A: Absorbed dose measures energy deposited, while equivalent dose accounts for radiation type using radiation weighting factors.

Q2: How is μ_en/ρ determined?
A: It's typically obtained from published tables based on material composition and photon energy.

Q3: What are typical fluence values in radiation therapy?
A: Fluence varies greatly depending on treatment modality, but may range from 10⁵ to 10¹² particles/cm².

Q4: How does this relate to clinical dose calculations?
A: TPS use more sophisticated algorithms, but this formula represents the fundamental physics principle.

Q5: What units are used in clinical dose reporting?
A: Gray (Gy) is the standard unit, with 1 Gy = 1 J/kg.