Physica

A catalog of its own — every working relation by specialty, with the formula, a live calculator, and a taught explanation.

• 00 FoundationsHow a photon dies in tissueThree ways a photon can vanish — and why the one that wins depends on energy and atomic number.8 min · EN FR AR ES
• 01 TherapyFrom isocenter to monitor unitsInverse square, percent depth dose, and the MU you will actually type.9 min · EN FR AR ES
• 02 ImagingDose indices you will be askedCTDI, DLP, SSDE, and why a single CTDI is not the patient's dose.8 min · EN FR AR ES
• 03 NuclearActivity, wait, and the number on the reportDecay is not a nuisance. It is the clock of every elution, every SUV, every delayed image.8 min · EN FR AR ES
• 04 ProtectionTime, distance, shielding — then the wallThe three controls you already know, written so a barrier calculation has a place to start.7 min · EN FR AR ES
• 05 BiologyFractionation is a languageLinear-quadratic survival, BED, and EQD2 — how a 2-gray fraction and a 8-gray fraction stop being comparable until you convert.8 min · EN FR AR ES
• 06 DoseFrom charge in a cavity to gray in waterBragg–Gray, TG-51, kQ and kTP — the chain that turns a coulomb into absorbed dose.8 min · EN FR AR ES
• 07 MRIA clock, a tip, a recoveryLarmor frequency, the RF tip, and T1/T2 — contrast is a timing choice.8 min · EN FR AR ES
• 08 UltrasoundA click, an echo, a shiftImpedance sends the echo home. Time is depth. Motion is Doppler. That is the whole craft.7 min · EN FR AR ES

A lecture cinema of its own — specialty films and machine films, with voice, a laser you can hide, and a notebook.

• 
  00 FoundationsHow a photon dies in tissueThree ways a photon can vanish — and why the one that wins depends on energy and atomic number.8 min · Lecture
• 
  01 TherapyFrom isocenter to monitor unitsInverse square, percent depth dose, and the MU you will actually type.9 min · Lecture
• 
  02 ImagingDose indices you will be askedCTDI, DLP, SSDE, and why a single CTDI is not the patient's dose.8 min · Lecture
• 
  03 NuclearActivity, wait, and the number on the reportDecay is not a nuisance. It is the clock of every elution, every SUV, every delayed image.8 min · Lecture
• 
  04 ProtectionTime, distance, shielding — then the wallThe three controls you already know, written so a barrier calculation has a place to start.7 min · Lecture
• 
  05 BiologyFractionation is a languageLinear-quadratic survival, BED, and EQD2 — how a 2-gray fraction and a 8-gray fraction stop being comparable until you convert.8 min · Lecture
• 
  06 DoseFrom charge in a cavity to gray in waterBragg–Gray, TG-51, kQ and kTP — the chain that turns a coulomb into absorbed dose.8 min · Lecture
• 
  07 MRIA clock, a tip, a recoveryLarmor frequency, the RF tip, and T1/T2 — contrast is a timing choice.8 min · Lecture
• 
  08 UltrasoundA click, an echo, a shiftImpedance sends the echo home. Time is depth. Motion is Doppler. That is the whole craft.7 min · Lecture

• Linear acceleratorC-arm linac in the bunker — monitor chamber, MLC, and the beam at isocenter.58 eq.
• CT scannerDiagnostic CT — tube and detectors in the gantry, dose along the scanned length.7 eq.
• MRI scannerWide-bore magnet — B₀, gradients, and the RF coil on the patient.23 eq.
• PET/CTHybrid scanner — coincidence ring behind, CT for attenuation in front.16 eq.
• Gamma cameraDual-head SPECT — crystal, PMTs, and the collimator facing the patient.6 eq.
• Radiography roomCeiling tube, table, and wall Bucky — geometry, technique, and detector dose.25 eq.
• UltrasoundProbe on tissue — impedance, Doppler, and the console that sets PRF and MI.21 eq.
• Mammography unitC-arm with compression paddle — target/filter and average glandular dose.1 eq.
• Brachytherapy suiteHDR afterloader and C-arm — source in the safe, dwell in the applicator.4 eq.
• Water phantomScanning tank under the linac — TG-51 / TRS-398 reference dosimetry.20 eq.
• Treatment vaultMaze and barriers — time, distance, shielding, WUT, and weekly dose.18 eq.
• Hot labGenerator, dose calibrator, and L-block — activity, breakthrough, Marinelli.12 eq.
• Proton gantryNozzle and snout — residual range, RBE 1.1, and the Bragg peak in the patient.5 eq.