{"id":3721,"date":"2025-03-05T11:41:36","date_gmt":"2025-03-05T10:41:36","guid":{"rendered":"http:\/\/www.zsvltava.cz\/fyzika\/?p=3721"},"modified":"2025-04-10T07:55:22","modified_gmt":"2025-04-10T05:55:22","slug":"zareni-radiace-atomu","status":"publish","type":"post","link":"https:\/\/www.zsvltava.cz\/fyzika\/?p=3721","title":{"rendered":"Z\u00e1\u0159en\u00ed a radiace atom\u016f"},"content":{"rendered":"

Elektromagnetick\u00e9 z\u00e1\u0159en\u00ed – vznik\u00e1 p\u0159i p\u0159echodech elektron\u016f mezi energetick\u00fdmi hladinami v elektronov\u00e9m obalu atomu. Zahrnuje \u0161irok\u00e9 spektrum vlnov\u00fdch d\u00e9lek od gama z\u00e1\u0159en\u00ed p\u0159es rentgenov\u00e9, ultrafialov\u00e9 a viditeln\u00e9 sv\u011btlo a\u017e po infra\u010derven\u00e9 z\u00e1\u0159en\u00ed. Energie vyz\u00e1\u0159en\u00e9ho fotonu odpov\u00edd\u00e1 rozd\u00edlu energi\u00ed mezi po\u010d\u00e1te\u010dn\u00ed a kone\u010dnou hladinou elektronu.<\/strong><\/p>\n

\u010c\u00e1sticov\u00e9 z\u00e1\u0159en\u00ed<\/strong> – emitovan\u00e9 p\u0159i procesech v atomov\u00e9m j\u00e1d\u0159e, typicky p\u0159i radioaktivn\u00edch p\u0159em\u011bn\u00e1ch. Zahrnuje p\u0159edev\u0161\u00edm:<\/p>\n

– Alfa z\u00e1\u0159en\u00ed (proud jader helia)
\n– Beta z\u00e1\u0159en\u00ed (proud elektron\u016f nebo pozitron\u016f)
\n– Neutronov\u00e9 z\u00e1\u0159en\u00ed<\/p>\n

Zat\u00edmco elektromagnetick\u00e9 z\u00e1\u0159en\u00ed souvis\u00ed p\u0159ev\u00e1\u017en\u011b s procesy v elektronov\u00e9m obalu, \u010d\u00e1sticov\u00e9 z\u00e1\u0159en\u00ed je spojeno p\u0159edev\u0161\u00edm s jadern\u00fdmi reakcemi a p\u0159em\u011bnami nestabiln\u00edch izotop\u016f.<\/p>\n

Radiace atom\u016f<\/h2>\n

Toto ozna\u010den\u00ed se pou\u017e\u00edv\u00e1 v souvislosti s energetick\u00fdm vyza\u0159ov\u00e1n\u00edm (ionizuj\u00edc\u00ed radiace). M\u016f\u017ee zahrnovat radioaktivn\u00ed procesy (nap\u0159. radium emituje alfa \u010d\u00e1stice) i elektromagnetick\u00e9 z\u00e1\u0159en\u00ed (nap\u0159. atomy v excitovan\u00e9m stavu vyza\u0159uj\u00ed fotony).<\/p>\n

Ka\u017ed\u00e9 elektromagnetick\u00e9 z\u00e1\u0159en\u00ed z atomu je jeho radiace, ale ne ka\u017ed\u00e1 radiace atomu je elektromagnetick\u00e9 z\u00e1\u0159en\u00ed \u2013 m\u016f\u017ee to b\u00fdt i \u010d\u00e1sticov\u00e9 z\u00e1\u0159en\u00ed.<\/p>\n

\u010c\u00edm d\u00e1le je elektron od j\u00e1dra, t\u00edm v\u011bt\u0161\u00ed energii m\u00e1\/pot\u0159ebuje k udr\u017een\u00ed v dan\u00e9 hladin\u011b. Pokud se uvoln\u00ed m\u00edsto v ni\u017e\u0161\u00ed hladin\u011b (bl\u00ed\u017ee k j\u00e1dru), elektron se na tuto hladinu p\u0159em\u00edst\u00ed. V ni\u017e\u0161\u00ed hladin\u011b ji\u017e tolik energie nepot\u0159ebuje a tak se p\u0159ebytek uvoln\u00ed – vyz\u00e1\u0159\u00ed<\/strong>. <\/p>\n

Energie se vyza\u0159uje postupn\u011b, ale v kvantech<\/strong> – p\u0159edem stanoven\u00fdch mno\u017estv\u00edch (bal\u00ed\u010dc\u00edch). Kvantum energie vyz\u00e1\u0159en\u00e9 p\u0159i p\u0159echodu elektronu z vy\u0161\u0161\u00ed vrstvy do ni\u017e\u0161\u00ed ozna\u010dujeme jako foton<\/strong>. Foton je druh \u010d\u00e1stice. Na\u0161e oko je senzor schopn\u00fd tyto \u010d\u00e1stice zaznamenat.<\/p>\n

Energie se \u0159\u00edd\u00ed n\u00e1sleduj\u00edc\u00edm vztahem:<\/p>\n

  <\/span>   <\/span>\"\[<\/p>\n

Kde h<\/em> je Planckova<\/a> konstanta a f<\/em> je frekvence z\u00e1\u0159en\u00ed. Jeliko\u017e je energie jednotliv\u00fdch vrstev dan\u00e1, konstanta se tak\u00e9 nem\u011bn\u00ed, vid\u00edme, \u017ee elektrony z r\u016fzn\u00fdch vrstev budou vykazovat r\u016fzn\u00e9 frekvence.<\/p>\n

– Energie p\u0159echodu je dan\u00e1 rozd\u00edlem mezi dv\u011bma hladinami a z\u016fst\u00e1v\u00e1 stejn\u00e1.
\n– Frekvence fotonu se m\u011bn\u00ed podle t\u00e9to energie, proto\u017ee foton m\u00e1 specifickou frekvenci, kter\u00e1 souvis\u00ed s jeho energi\u00ed.<\/p>\n

Pokud je p\u0159echod mezi vy\u0161\u0161\u00edmi hladinami (v\u011bt\u0161\u00ed energetick\u00fd rozd\u00edl), frekvence fotonu bude vy\u0161\u0161\u00ed (co\u017e odpov\u00edd\u00e1 sv\u011btlu na modr\u00e9m nebo ultrafialov\u00e9m konci spektra), a pokud je p\u0159echod mezi ni\u017e\u0161\u00edmi hladinami (men\u0161\u00ed energetick\u00fd rozd\u00edl), frekvence bude ni\u017e\u0161\u00ed (co\u017e odpov\u00edd\u00e1 sv\u011btlu na \u010derven\u00e9m konci spektra).<\/p>\n

Tento mechanizmus funguje i obr\u00e1cen\u011b. Pokud elektron p\u0159ech\u00e1z\u00ed do vy\u0161\u0161\u00ed vrstvy, mus\u00ed nejprve z\u00edskat – absorbovat ur\u010dit\u00e9 mno\u017estv\u00ed energie.<\/p>\n

Podle vlnov\u00e9 d\u00e9lky (frekvence) d\u011bl\u00edme z\u00e1\u0159en\u00ed:<\/p>\n