Studying the engineering design of a Mass Spectrometer and learned that an element undergoing mass spectrometry is first ionized by being bombarded by electrons. The electrons comes from a source like a tungsten metal and then once atoms gets collided with electrons, the atoms’ electrons get stripped away turning the atom from neutral into an ion, positive ion . Then these ions gets accelerated by an electric field until it reaches a magnetic field which deflects these ions. The deflection angle varies and serves as specific signatures for the different isotopes of an element.
It turns out that a mass spectrometer is a kind of a particle accelerator which I am very much interested to learn since 2015 but didn’t have much time and with the lack of foundational knowledge back then. Today I am very much excited to learn about this.
An interesting note here is the generation of electrons for use on bombarding the target element. The process to emit electrons is to introduce a high energy into the atom, say a metal like tungsten with heat. Energy input into the metal goes to the metal’s atoms and the energy input triggers specific electrons on orbitals to move to a different orbital levels. With the appropriate amount of energy input, the electrons can escape the orbital and became free electrons which is then moves to an attractor and passes through the target element in the form of a molecular cloud as a gas.
The term thermoionic emission got me confused and I was scratching my head, how did an electron been classified as an ion? The confusion stems from the historic usage of the word thermoionic in which the root word ion was historically associated with charged particles such as an electron.
Now that thermoionic emission is clear, the next conceptual jump is on my rudimentary understanding of an electric field. I initially thought that the positive ions are moved by following an attractor, such as an electron in a moving charge in a circuit. That understanding is wrong.
Deep diving on the concept of an Electric Field brings me back to my readings on theoretical physics about Fields. So What is an Electric Field? It is a space where an electric charge exist and experiences a force. That means a positive ion can be made to accelerate by having it in between two points where electrical potential difference exist, which is a voltage, without the need for a moving charge or an electron. The positive ion will accelerate from the direction of the positive potential to a negative potential.
For the magnetic field, because of the lack of academic treatment on Maxwell’s Equations, I lack the mathematical knowledge and intuition for a magnetic field. This is the next action item, I need to understand a magnetic field in order to understand how it deflects an accelerating positive ions in a mass spectrometer device.
On the other hand, I need to plan for the new route for the 30km run upgrade for the end of the year. My 21km run route starts from my place then follows the road along the long shoreline up to the end of it in the next town then I head back which completes the 21km distance. For the 30km distance I need to add a 9km distance but I don’t want to keep traversing the same path because it is boring.
Time runs so fast and the annual IEEE membership is coming. I think there is discount if I renew for 2027 membership before the year ends. Will have to remove society membership on oceanic engineering and the one on cyber-physical systems and will return to control systems society while retaining my aerospace and electronics system society membership. I might add an new society membership such as nuclear and plasma science society and probably another one.
This site will hold short thoughts, daily observations, technical discoveries, project progress, and records that do not require a full article.