Глосарій

E detector, ΔE detector /  E детектор, ΔE детектор       
The E detector is a detector with a thickness enough to cover the range of high energy particles. It is designed for detecting the total energy of a particle. The ΔE detector in contrast is made thin enough to allow the particles being detected to pass through it so that the specific energy loss in the particle can be detected. A combination of a ΔE detector and E detector is called the ΔE-E detector and is an effective means of identifying particles.

ENI (Equivalent Noise Input) - Photomultiplier tube /  Еквівалентний шумовий вхідний сигнал – Фотоелектронний помножувач
ENI indicates the photon-limited signal-to-noise ratio. ENI refers to the amount of light in watts necessary to produce a signal-to-noise ratio of unity in the output of a photomultiplier tube. The value of ENI is given by the equation on the left. 

q = electronic charge (1.60 x 10^-19 coul.)
Idb = anode dark current in amperes after 30-minute storage in darkness
μ = gain
△f = bandwidth of the system in hertz (usually 1 hertz)
S = anode radiant sensitivity in amperes per watt at the wavelength of interest       

eV (electron volt) /  еВ (електрон-вольт)      
Energy acquired by an electron when it is accelerated through a potential difference of 1 V in a vacuum. This is generally used as a unit to express the energy of elementary particles, atomic nuclei, atoms, molecules, etc.

Eye diagram /  Очна діаграма       
This is a superimposed display of all waveforms for possible encoded strings, used to perform a comprehensive evaluation of the waveform distortion of the transmitted encoded pulses. This is also called the eye pattern.

Excitation /  Збудження       
In semiconductors, excitation refers to the process of raising electrons from a low-energy valence band to the higher-energy conduction band. If electrons are excited by heat, this process is called thermal excitation. If an electron is excited by light, then this process is called photoexcitation. It occurs when light is absorbed by a photodiode.

Extinction ratio /  Коефіцієнт затухання
The ratio of the minimum value to the maximum value in the light power that varies during intensity modulation of light waves. In digital optical communications, this is defined as the ratio of the light power for transferring logic “1” to the light power for transferring logic “0.” This extinction ratio is ex- pressed in either linear ratio, dB, or %.

[Extinction ratio in digital optical communications]
Extinction ratio (linear ratio) = I(1)/I(0)
Extinction ratio [dB] = 10 log10 {extinction ratio (linear ratio)}
Extinction ratio [%] = I(0)/I(1) × 100

I(1): light power for transferring logic “1”
I(0): light power for transferring logic “0”