Spektrum / The Electromagnetic Spectrum

ozn.	kmitočet vln. délka	ozn.	příklady
velmi nízké myriametrové	3–30 kHz 100–10 km	VLF	zvuk: 20 Hz – 20 kHz 15 000–15 km
nízké kilometrové	30–300 kHz 10–1 km	LF/LW	International AM radio
střední hektometrové	300–3000 kHz 1000–100 m	MF/MW	AM broadcast SV ~1000 kHz ~300 m
vysoké dekametrové	3–30 MHz 100–10 m	HF/SW	odraz od ionosféry
velmi vysoké metrové	30–300 MHz 10–1 m	VHF/VKV	FM,TV; ~100 MHz ~3 m
ultravysoké decimetrové	300–3000 MHz 100–10 cm	UHF <30 cm Microwave	TV mobily GSM Evropa: 900 MHz~30 cm, USA: 1900 MHz~16 cm GPS: L1 (1575.42 MHz ~19 cm), L2 (1227.60 MHz ~24.4 cm) mikrovlnná trouba: 2,45 GHz ~12,23 cm Wi-Fi: 2,4 GHz ~12,5 cm; 5 GHz ~6 cm Bluetooth: 2.4–2.4835 GHz ~12,1–12,5 cm
superiorní centimetrové	3–30 GHz 10–1 cm	SHF cm Microwave	kanály GEO družic (uplink/downlink): C 6/4 GHz; Ku 14/11 GHz; Ka 30/20 GHz
extrémně vysoké milimetrové	30–300 GHz 10–1 mm	EHF mm Microwave

1 mm –790 nm 2.898–3400 K 300 GHz –380 THz	IR, infračervené záření	near IR .79–5 μm (3400–600 K) mid IR 5–25 μm (600–115 K) far IR 25–200 μm (115–14.5 K) (sub-)millimeter .1–1000 mm (30–2.898 K) Dominating radiation: near IR (solar) .7–2.5 μm far IR (terrestrial) 2.5–1000 μm	reliktní záření: 1,06 mm ~ 2,74 K lidské tělo 37°C ~ 9.3 μm
790–390 nm 3400–7400 K	viditelné záření 380–770 THz 1,6–3,18 eV		fotosféra ~5800 K ~500 nm slun. skvrny ~4000 K ~725 nm
390–10 nm 7400–300 tis. K 770 THz –30 PHz (peta-) 3.18–124 eV	UV, ultrafialové záření	EUV/XUV 10–100 nm (300 000–30 000 K) FUV/VUV 100–200 nm (30 000–15 000 K) MUV 200–300 nm (15 000–9700 K) NUV 300–390 nm (9700–7400 K)	V biomedicíně: UV-C 15–280 nm; UV-B 280–315 nm UV-A 315–400 nm chromosféra ~20 000 K ~145 nm fotoionizace (prahové hodnoty): O 102.7 nm ,O₂ 91.1 nm, N₂ 79.6 nm
10–0.01 nm (10 pm) 300 000–300 mil. K 30 PHz – 30 EHz 124 eV – 124 keV	X rays, rentgenové záření	soft, měkké hard, tvrdé	slun. koróna ~1–2 mil. K slun. erupce >~2 mil. K
>0.01 nm = 10 pm >300 mil. K > 30 EHz (exa-)	gamma rays, záření gama		solar flares terrestrial lightning (?)

Spektrum – přepočty vlnových délek, frekvencí, teplot – výpočetní pomůcka
Lithium fluoride is the material with the most extreme UV transmission of all and is used for special UV optics. It transmits well into the VUV region at the hydrogen Lyman-alpha line (121nm) and beyond. http://www.crystran.co.uk/lifdata.htm
vacuum ultraviolet (VUV). Usually considered to be the portion of the electromagnetic spectrum between 100 nm and 200 nm. Due to the light-absorbing characteristics of air for wavelengths below 200 nm, measurement equipment must be evacuated of air. Hence the term "vacuum ultraviolet."
near infrared (NIR). The area of the spectrum between 700 nm and 2500 nm (2.5 µm) http://www.acton-research.com/aro/library-glossary.shtml
geomagnetická bouře: 1989, March 13, in Montreal, 6 million people were without commercial electric power for 9 hours ( the Hydro-Quebec electric power system)
ionizační energie vodíku, hladina s nejnižší energií 13,6 eV ~91.2 nm, začátek Lymanovy UV série, n=1; začátek Balmerovy VIS série, n=2, má 365 nm (UV-A), druhý stav 656 nm, a bright red line in the spectrum of Hydrogen, usually called the "hydrogen alpha" line Hα
UV-A covers the wavelength range 320–400 nm. UV-A is not absorbed by the ozone layer and is the least harmful UV radiation.
UV-B covers the wavelength range 280–320 nm. UV-B is more energetic than UV-A, and is partially absorbed by the ozone layer. UV-B rays that are not filtered out cause sunburn and other harmful effects to humans.
UV-C covers the wavelength range 100–280 nm. UV-C is the most dangerous form of UV radiation, but is completely absorbed by the ozone layer. Artificial UV-C (for example emitted by electric discharges) is a threat for certain occupational group, like welders.

Ionosférické vrstvy:

ozn	km	LUF	MUF	ionty	max. absorpce
D	50–95				f <7 MHz; tvrdé X <5 nm; NO pohl. UV>102.6 nm, zejm. 121.6 Ly_α
E	90–150	3 MHz	5 MHz	O₂⁺	90–100 nm; měkké rentg.
F1	150–200		10 MHz	NO⁺	10–80 nm
F2	200–500		20 MHz	O⁺

Mimosa datová linka: 2 kanály 2,281 GHz a 2,282 GHz (13,1 cm);
povelová linka: 2 linky 450,200 MHz a 450,250 MHz (66,6 cm);
majáček: 137,150 MHz (2,186 m)
Interstellar hydrogen with a wavelength of 21 cm Interstellar space is filled with extremely tenuous clouds of gas which are mostly Hydrogen. The neutral hydrogen atom (HI in astronomer's shorthand) consists of 1 proton and 1 electron. The proton and electron spin like tops but can have only two orientations; spin axes parallel or anti-parallel. It is a rare event for Hydrogen atoms in the interstellar medium to switch from the parallel to the anti-parallel configuration, but when they do they emit radio waves with a wavelength of 21 centimeters (about 8 inches) and a corresponding frequency of exactly 1420 MHz.
chromosféra: H_α 656,3 nm ~ 4416 K; H_β 486,1 nm ~ 5962 K
ionized calcium Ca II - the K line: 393.4 nm ~ 7366 K; the H line: 396.8 nm ~ 7303 K
hélium: D3 587,6 nm ~ 4932 K

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