Using Raidation2D
Tsumoru Shintake 2008
Shintake@oist.jp
1. About 2008 Version
After starting delivering original version of Radiation2D.exe, it has been 10 years past.
There were about 5000 downloads from whole over the world	  This 2008 version is single executable file: Radiation2D.exe, which can be start up from
Desktop or USB memory.
2. Starting program.
Copy or download program to desktop or your preferred folder. Double click icon, then it
will start to run. In case if you use Mac, you need Windows emulation software, such as,Parallels.
Mac and iPad version will be ready soon.
3. Initial condition is “Moving by Mouse”
Bring your mouse pointer on to center circle (electron), press left button and drag to mover.
Wave like motion starts to run along with blue lines (electric field lines), this is the radiationof electro-magnetic wave.
In reality, the speed of the wave is the speed of the light, which is very fast: c = 3 x 108
m/sec, thus your eye
cannot catch. To show iton graphics, the speed ofthe light is made very
slow: ~10 cm/sec, or you
may think time elapses
very slowly.

By moving red circle (electron) at the center, using you mouseby pressing left button, the wave start to propagate outward, thisis the electromagnetic wave.

4. Controls View
Expanding: Pressing left mouse button and drag. Selected area is expanded.

Rset expand: Press left mouse button, and drag to left-up direction, then expansion will be rest.

Panning: Press right mouse button, and drag to any direction.	 

5. Pause Motion
You may pause execution by press yellow pause button at left upper corner. Press button again,
single simulation step will be executed. You may restart by pressing green arrow button.

When Ration2D runs, it uses fully 100% CPU resource. When you want to show Radiation2D
during your presentation, it will be a good idea to pause execution when you show otherpresentation.
6. Selecting various kinds of radiations.
You can select kinds of radiations, i.e., preset automatic motion of electron, from the “SetupTrajectory” pull down menu.

From the top
by Mouse: using mouse, you may move electron in any directions. Maximum speed is limited
below speed of light (speed of wave propagation).
Line: constant speed motion along straight line.
Dipole radiation: Sinuous oscillation along straight line, which generates dipole radiation pattern.
Actually this type of radiation is utilized as radiofrequency wave, which plays key role oftelecommunications systems, such as cell phones. In shorter wavelength, most of all visible
radiations are from dipole motion of electrons in atoms, when it jumps from one quantum state to theothers. Random zigzag motion of electrons also generates random electromagnetic radiation as
thermal radiation (such as the heat from sun).
Circle: When electron runs in circular trajectory, it creates spiral pattern. This is the synchrotron
radiation. Scientists use circular accelerator to generate synchrotron radiation at X-ray wavelength,
which is very useful radiation to analyze materials. On the other hand, far galaxy, high-energy
electrons are running with curved trajectory in the space magnetic field, generating visible light andalso X-rays, known as cosmic synchrotron radiations, important radiation to study cosmology.
Undulator: When an electron passes through a periodic magnetic field produced “undulator”, itgenerates focused quasi-monochromatic X-ray beam, called undulator radiation. Modern
synchrotron radiation facilities equipped many undulators, to produce high quality X-ray beams forvarious scientific analysis, most importantly analyze atomic structure of protein crystals.
Racetrack: Electron runs on racetrack trajectory. You may learn the radiation is only created fromthe curved trajectory, not from linear motion. Radiation is only generated by the accelerating motionof charged particle.
Bending Magnet: Incoming electron enters to bending magnet, suddenly start turning, and generates
radiation. By looking carefully the field pattern along electron motion, you will find longitudinal
field components in front of electron, which becomes source of CSR effect.