Pozdn\u00ed v\u00fdvojov\u00e9 f\u00e1ze hmotn\u00fdch hv\u011bzd obest\u00edr\u00e1 cel\u00e1 \u0159ada nevy\u0159e\u0161en\u00fdch nejasnost\u00ed. Pozorov\u00e1n\u00ed t\u011bchto hv\u011bzd \u010dasto nesouzn\u00ed s teoretick\u00fdmi modely, co\u017e komplikuje stanoven\u00ed jejich parametr\u016f a pozice na v\u00fdvojov\u00e9m diagramu. Julieta S\u00e1nchez Arias se v p\u0159edstavovan\u00e9 pr\u00e1ci, kter\u00e1 je prvn\u00ed z \u0159ady publikac\u00ed na toto t\u00e9ma, zab\u00fdvala zevrubnou anal\u00fdzou t\u0159ech nadob\u0159\u00edch hv\u011bzd. <\/p>\n\n\n\n
Velmi hmotn\u00e9 hv\u011bzdy jsou v centru z\u00e1jmu astrofyzik\u016f nejen kv\u016fli jejich vz\u00e1cnosti, ale p\u0159edev\u0161\u00edm proto, \u017ee jsou nesm\u00edrn\u011b d\u016fle\u017eit\u00fdmi slo\u017ekami hv\u011bzdn\u00e9 populace. Kv\u016fli sv\u00e9mu rychl\u00e9mu v\u00fdvoji a spektakul\u00e1rn\u00edm konc\u016fm jsou kl\u00ed\u010dov\u00fdmi faktory pro obohacov\u00e1n\u00ed mezihv\u011bzdn\u00e9ho prost\u0159ed\u00ed o t\u011b\u017e\u0161\u00ed prvky, tvorbu dal\u0161\u00edch generac\u00ed hv\u011bzd a celkov\u00fd v\u00fdvoj galaxi\u00ed. Jejich fyzik\u00e1ln\u00ed popis je ov\u0161em pon\u011bkud komplikovan\u011bj\u0161\u00ed, nebo\u0165 tato pozdn\u00ed st\u00e1dia v\u00fdvoje hmotn\u00fdch hv\u011bzd jsou spojena s celou \u0159adou dynamick\u00fdch proces\u016f. S p\u0159ekotnou konvekc\u00ed v rozepnut\u00fdch ob\u00e1lk\u00e1ch, s pulsacemi, s v\u00fdskytem obecn\u011b t\u011b\u017eko popsateln\u00e9ho hv\u011bzdn\u00e9ho v\u011btru. V\u0161echny tyto jevy jsou pops\u00e1ny jen s omezenou p\u0159esnost\u00ed.<\/p>\n\n\n\n
V d\u016fsledku t\u011bchto i jin\u00fdch neznalost\u00ed je pak obt\u00ed\u017en\u00e9 ur\u010dit z\u00e1kladn\u00ed parametry takov\u00fdch hv\u011bzd, jako je hmotnost, rozm\u011bry, nebo chemick\u00e9 slo\u017een\u00ed. Dokonce i mal\u00e9 nep\u0159esnosti mohou v\u00e9st k velk\u00fdm nejistot\u00e1m ve v\u00fdvojov\u00fdch modelech. I p\u0159es \u00fasil\u00ed v\u00fdzkumn\u00fdch t\u00fdm\u016f se spolehlivost anal\u00fdz zat\u00edm nedostate\u010dn\u011b zlep\u0161ila. Velmi hmotn\u00e9 hv\u011bzdy v t\u00e9to f\u00e1zi v\u00fdvoje mohou opakovan\u011b proch\u00e1zet st\u00e1diem modr\u00e9ho nadobra (co\u017e je term\u00edn popisuj\u00edc\u00ed pozorovan\u00e9 vlastnosti) a na prvn\u00ed pohled nen\u00ed jasn\u00e9, zda jde o hv\u011bzdu p\u0159ed st\u00e1diem rud\u00e9ho obra, o hv\u011bzdu po pr\u016fchodu posloupnost\u00ed rud\u00fdch obr\u016f, p\u0159i nich\u017e ztratila chladn\u00e9 ob\u00e1lky a jev\u00ed se zd\u00e1nliv\u011b mod\u0159ej\u0161\u00ed, nebo zda jde o hv\u011bzdu, kter\u00e1 spolkla sv\u00e9ho m\u00e9n\u011b hmotn\u00e9ho pr\u016fvodce a na jeho \u00fakor se zd\u00e1nliv\u011b omladila.<\/p>\n\n\n\n
T\u00fdm kolem Juliety S\u00e1nchez Arias zah\u00e1jil systematick\u00fd v\u00fdzkum modr\u00fdch nadobr\u016f s\u00a0c\u00edlem z\u00edskat v\u00edce informac\u00ed o\u00a0jejich v\u00fdvojov\u00e9m st\u00e1diu. Tento rozs\u00e1hl\u00fd projekt vych\u00e1z\u00ed jednak z\u00a0po\u0159\u00edzen\u00ed nov\u00fdch spektroskopick\u00fdch dat s\u00a0vysok\u00fdm rozli\u0161en\u00edm, s\u00a0vyu\u017eit\u00edm archivn\u00edch pozorov\u00e1n\u00ed, ale sou\u010dasn\u011b v\u00a0kooperaci s\u00a0modelov\u00e1n\u00edm vlastnost\u00ed t\u011bchto hv\u011bzd s\u00a0pomoc\u00ed nejmodern\u011bj\u0161\u00edch po\u010d\u00edta\u010dov\u00fdch model\u016f. P\u0159edstavovan\u00e1 pr\u00e1ce je prvn\u00ed z\u00a0p\u0159edpokl\u00e1dan\u00e9 s\u00e9rie, kter\u00e1 na p\u0159\u00edpad\u011b t\u0159\u00ed exempl\u00e1\u0159\u016f odhaluje pou\u017e\u00edvanou metodologii.<\/p>\n\n\n\n
Pokra\u010dov\u00e1n\u00ed na webu ASU<\/a><\/p>\n\n\n\n Popis obr\u00e1zku<\/strong>: Adhara (\u03b5 CMa) je dvojhv\u011bzdou nach\u00e1zej\u00edc\u00ed se ve vzd\u00e1lenosti asi 430 sv\u011bteln\u00fdch let. Prim\u00e1rn\u00ed slo\u017eka (modr\u00fd nadobr) je nejjasn\u011bj\u0161\u00edm zdrojem na obloze v extr\u00e9mn\u00ed ultrafialov\u00e9 oblasti spektra a nejsiln\u011bj\u0161\u00edm ionizuj\u00edc\u00edm zdrojem vod\u00edku ve slune\u010dn\u00edm okol\u00ed. P\u0159ed 4,7 miliony lety byla Adhara nejjasn\u011bj\u0161\u00ed hv\u011bzdou na obloze. (cc) Pablo Carlos Budassi, velikostn\u00ed srovn\u00e1n\u00ed se Sluncem p\u0159idala Julieta S\u00e1nchez Arias.<\/p>\n<\/blockquote>\n\n\n\n Pozdn\u00ed v\u00fdvojov\u00e9 f\u00e1ze hmotn\u00fdch hv\u011bzd obest\u00edr\u00e1 cel\u00e1 \u0159ada nevy\u0159e\u0161en\u00fdch nejasnost\u00ed. Pozorov\u00e1n\u00ed t\u011bchto hv\u011bzd \u010dasto nesouzn\u00ed s teoretick\u00fdmi modely, co\u017e komplikuje stanoven\u00ed jejich parametr\u016f a pozice na v\u00fdvojov\u00e9m<\/p>\n","protected":false},"author":1,"featured_media":2871,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[37,32],"tags":[],"class_list":["post-2869","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-horke-hvezdy","category-novinky"],"_links":{"self":[{"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/posts\/2869","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/comments?post=2869"}],"version-history":[{"count":3,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/posts\/2869\/revisions"}],"predecessor-version":[{"id":2874,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/posts\/2869\/revisions\/2874"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/media\/2871"}],"wp:attachment":[{"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/media?parent=2869"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/categories?post=2869"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/stel.asu.cas.cz\/cs\/wp-json\/wp\/v2\/tags?post=2869"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\n
Dal\u0161\u00ed informace<\/h4>\n\n\n\n
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