Mass Spectrometry, Cyclotrons, and Particle Accelerators

All flashcards

What is the role of gas chromatography when paired with mass spectrometry?

It separates mixture components over time before mass spectrometry analyzes them.

What observation indicates a leak in a helium leak test?

Helium is detected in the compartment intended to remain isolated.

What are the two main functions of the fields in a cyclotron?

The electric field accelerates particles across the gap; the magnetic field bends them inside the dees.

Why does a conventional cyclotron lose synchrony at relativistic speeds?

The particle’s orbital period changes, while the cyclotron’s voltage frequency remains fixed.

How does a synchrotron keep a beam in an approximately fixed-radius orbit?

It increases the bending magnetic field as particle momentum rises.

Quiz questions

1. What condition allows an ion to pass straight through a velocity selector?Answer: The electric and magnetic forces have equal magnitudes and opposite directions.
2. Two ions have the same speed and charge magnitude in the same analyzer field. If one has twice the mass, how do its path radius and the other ion’s radius compare?Answer: The more massive ion follows a path with twice the radius.
3. In the classical model, what is the orbital period of a particle with charge magnitude $q$ and mass $m$ in a uniform magnetic field $B$?Answer: $T=2\pi m/(qB)$
4. A positively charged particle crosses a cyclotron gap through a potential difference of magnitude $V$. By how much does its kinetic energy increase?Answer: By $qV$.
5. What limits the energy of a basic cyclotron when particles approach the speed of light?Answer: The particle’s changing orbital period causes it to fall out of step with the fixed-frequency voltage.