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# Observing the epoch of galaxy formation

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## Abstract

Significant observational progress in addressing the question of the origin and early evolution of galaxies has been made in the past few years, allowing for direct comparison of the epoch when most of the stars in the universe were forming to prevailing theoretical models. There is currently broad consistency between theoretical expectations and the observations, but rapid improvement in the data will provide much more critical tests of theory in the coming years.

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... Иллюстрация метода многоцветной фотометрии, используемого при поиске далеких галактик. Показано изменение наблюдаемого спектра за счет красного смещения [18] Корреляция между активностью галактик и их взаимодействием и слияниями также является сейчас уже хорошо установленным наблюдательным фактом [6,19,11]. Малая концентрация квазаров и радиогалактик позволяет возникать им даже за счет очень редких соударений или слияний. ...
... При таких наблюдениях используется метод многоцветной фотометрии в полях глубоких обзоров космического телескопа Хаббла и крупнейших наземных телескопов [1,2]. Принцип легко понять из рисунка, заимствованного из обзора [18] одного из авторов этого метода (Рис.1). Благодаря большому красному смещению, изображения далеких галактик исчезают в ультрафиолетовых и оптических фильтрах, и галактика видна только в красной или даже в ИК-области спектра (Рис. ...
... в разных фильтрах при использовании метода многоцветной фотометрии [18] 2.2. ЭВОЛЮЦИЯ КОНЦЕНТРАЦИИ НЕЙТРАЛЬНОГО ВОДОРОДА Другим эффектом, свидетельствующим о появлении звезд и галактик на больших красных смещениях, служит наблюдение вызываемой ими вторичной ионизации водорода. ...
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1 Институт радиофизики и электроники НАН Украины, Харьков; 2 Радиоастрономический институт НАН Украины, Харьков; 3 Харьковский национальный университет им. В.Н. Каразина, Харьков E-mail: ak_04@rambler.ru, vkont@ri.kharkov.ua Быстрая эволюция числа массивных галактик при красном смещении z =6, обнаруженная в последние годы при анализе сверхглубокого поля Хаббла и Субару, может быть объяснена взрывным характером про-цесса слияния галактик. 1. ВВЕДЕНИЕ Сообщение [1,2] об обнаружении в сверхглубо-ких полях Хаббла и Субару "внезапного" появления массивных галактик при красном смещении z=6 (см. также [3]), а также сообщение о наблюдении заклю-чительной стадии процесса вторичной ионизации в этот же период [4] (см. литературу и обсуждение в обзоре [5]) может свидетельствовать, по нашему мнению, так же как и эпоха возникновения квазаров [6], о взрывном характере эволюции галактик в ре-зультате слияний [7, 8]. Долгое время считалось, что после своего обра-зования в результате развития гравитационной не-устойчивости (из газового протогалактического об-лака), галактики эволюционируют сугубо индивиду-ально. Наблюдательные данные последних трех де-сятилетий, в особенности данные космического те-лескопа Хаббла и крупнейших наземных телеско-пов, дают убедительные доказательства опреде-ляющей роли слияний в космогонии галактик. Об-стоятельный обзор Кенникута, Швейцера и Барнса [9], посвященный взаимодействию и слиянию га-лактик и вызванному им индуцированному звездо-образованию (около 1000 ссылок и более 200 иллю-страций!) позволяет опустить здесь подробное опи-сание соответствующей библиографии и наблюда-тельных аргументов. Процессы слияний происходят в темной холодной материи (CDM), джинсова длина в которой мала, не-смотря на то, что эволюция происходит в горячей Вселенной. Первоначально возникшие флуктуации малых масс, порядка массы шаровых скоплений в эпоху рекомбинации водорода, сливаясь (и скучива-ясь) образуют за космологическое время массивные объекты – галактики (и их скопления). При этом све-тящееся барионное вещество представляет собой ма-лую примесь к темной материи в галактиках. ___________________________________________________________ ВОПРОСЫ АТОМНОЙ НАУКИ И ТЕХНИКИ. 2010. № 4. Серия: Плазменная электроника и новые методы ускорения (7), с.137-142. 137 В работах римской и харьковской групп в 90-е годы [7,8,10-14] показана возможность кинетиче-ского «фазового перехода» [15-17] в системе галак-тик, проявляющегося в самоускоряющемся процессе образования массивных галактик за счет слияний галактик малых масс – «эпоха» возникновения га-лактик. То есть процесс слияний при гравитацион-ном взаимодействии носит «взрывной характер». Взрывное поведение слияний существенно связано с зависимостью вероятности слияния от масс галак-тик. А именно, к взрывной эволюции и фазовому переходу приводит рост вероятности более быст-рый, чем первая степень массы [8, 10]. В современ-ных космологических теориях это обстоятельство либо игнорируется, либо учитывается недостаточно детально. "Внезапное" появление галактик при z = 6 можно пытаться рассматривать как наблюдательное свидетельство "взрывной" эволюции, чему и посвя-щена данная работа.
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