На Правах Рукописи Удк 524.3, 524.4, 524.6 Глушкова Елена

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На Правах Рукописи Удк 524.3, 524.4, 524.6 Глушкова Елена МОСКОВСКИЙ ГОСУДАРСТВЕННЫЙ УНИВЕРСИТЕТ имени М.В. ЛОМОНОСОВА ГОСУДАРСТВЕННЫЙ АСТРОНОМИЧЕСКИЙ ИНСТИТУТ имени П.К. ШТЕРНБЕРГА На правах рукописи УДК 524.3, 524.4, 524.6 Глушкова Елена Вячеславовна КОМПЛЕКСНОЕ ИССЛЕДОВАНИЕ РАССЕЯННЫХ ЗВЁЗДНЫХ СКОПЛЕНИЙ ГАЛАКТИКИ Специальность 01.03.02 ± астрофизика и звёздная астрономия Диссертация на соискание ученой степени доктора физико-математических наук Москва ± 2014 1 Оглавление Введение ...................................................................................................................................................4 Глава 1. Собственные движения и лучевые скорости РЗС..................................................................19 1.1. Абсолютные собственные движения..........................................................................................19 1.1.1 Абсолютизация собственных движений звёзд в 21 рассеянном скоплении.....................20 1.1.2 Оценка ошибок каталога 4М...............................................................................................27 1.1.3 Оценка параметров кривой вращения по собственным движениям 21 РЗС....................28 1.1.4 Абсолютные собственные движения 181 молодого скопления.........................................28 1.1.5 Кривая вращения подсистемы молодых рассеянных скоплений......................................37 1.1.6 Каталог абсолютных собственных движений РЗС.............................................................38 1.1.7 Членство звёзд в скоплениях...............................................................................................39 1.2 Лучевые скорости .......................................................................................................................40 1.2.1 Каталог лучевых скоростей рассеянных скоплений..........................................................40 1.2.2 Лучевые скорости скоплений NGC 6494, NGC 6694, NGC 6755 и NGC 6819................42 1.2.3 Исследование рассеянного звёздного скопления NGC 6811............................................48 1.2.4 Красные гиганты в поле NGC 1817.....................................................................................58 1.2.5 Переменность лучевых скоростей ярких красных звёзд в РЗС........................................64 Глава 2. Рассеянные скопления и цефеиды..........................................................................................66 2.1 Исследование изменяемости периодов цефеид, входящих в состав рассеянных скоплений и ассоциаций .........................................................................................................................................67 2.2 Распределение цефеид, рассеянных скоплений и ассоциаций в Галактике ...........................73 Глава 3. Поиск и открытие новых скоплений.......................................................................................77 3.1 Появление больших обзоров неба и первые работы по поиску новых скоплений..................77 3.2 Открытие новых звёздных скоплений в ГАИШ МГУ...............................................................79 3.2.1 Программа автоматического поиска звёздных скоплений...............................................80 3.2.2 Приложение разработанного метода к данным обзора 2MASS.......................................84 3.2.3 Результаты исследования области антицентра Галактики...............................................88 3.2.4 Открытие и исследование РЗС в галактической плоскости.............................................99 3.3 Интернет-каталог физических параметров РЗС......................................................................110 Глава 4. Изучение рассеянных скоплений по данным многоцветной фотометрии.........................114 4.1 Фотометрическое исследование РЗС в направлении рукава Персея.....................................114 4.1.1 Скопления King 13, King 18, King 19, King 20, NGC 136 и NGC 7245...........................114 Наблюдения и обработка данных..........................................................................................116 Результаты исследования скоплений....................................................................................121 4.1.2 Скопления Be 96, Be 97, King 12, NGC 7261, NGC 7296 и NGC 7788............................128 Получение данных ПЗС фотометрии в поле скоплений.....................................................129 Физические параметры РЗС...................................................................................................133 Изучение функции масс скоплений......................................................................................139 4.2 Оптическая фотометрия скоплений, открытых по обзору 2MASS ....................................142 4.2.1 Скопления Koposov 12, Koposov 53 и Koposov 77...........................................................142 Наблюдения и обработка данных..........................................................................................143 Определение параметров скоплений....................................................................................146 4.2.2 Скопления SAI 63 и SAI 75...............................................................................................155 Глава 5. Исследование структуры и кинематики молодого населения галактического диска......158 2 5.1 Анализ кривой вращения Галактики и параметры солнечного апекса..................................158 5.1.1 Использованные данные.....................................................................................................159 Расстояния до объектов.........................................................................................................160 Лучевые скорости...................................................................................................................161 Собственные движения..........................................................................................................162 5.1.2 Модель галактического вращения .............................................................................162 5.1.3 Определение расстояния до центра Галактики................................................................165 5.1.4 Результаты анализа.............................................................................................................166 5.2 Статистические параллаксы и кинематические параметры классических цефеид и молодых рассеянных скоплений.....................................................................................................................171 5.2.1 Метод анализа ....................................................................................................................173 5.2.2 Учет движения Солнца и дифференциального вращения выборки. ............................175 5.2.3 Преобразование координат, скоростей и тензора ковариации.......................................177 5.2.4 Распределение остаточных скоростей и функция правдоподобия................................179 5.2.5 Наблюдательный материал и вычисления........................................................................180 Классические цефеиды..........................................................................................................180 Молодые рассеянные скопления...........................................................................................182 5.2.6 Обсуждение результатов...................................................................................................190 5.3 Сравнение полученных нами результатов с современными...................................................192 ЗАКЛЮЧЕНИЕ....................................................................................................................................194 ЛИТЕРАТУРA......................................................................................................................................200 3 Введение Рассеянные звёздные скопления ± это, пожалуй, самые подходящие и наиболее ªинформативныеº объекты для исследования нашей Галактики. С точки зрения современных представлений о звёздообразовании скопления ± это ªкирпичикиº, из которых построена не только наша Галактика (или, как её часто называют, Млечный Путь), но и другие звёздные системы. Почти все звёзды рождаются в группах, которые сначала наблюдаются как концентрации звезд, погружённые в туманности, т.е. в родительские газо-пылевые облака (embedded clusters). По мере эволюции такие объекты превращаются, в зависимости от начальных условий, либо в гравитационно-связанные скопления, либо в несвязанные ассоциации звёзд, которые распадаются через несколько миллионов лет. Звездные скопления принято делить на рассеянные (РЗС) и шаровые (ШЗС) в зависимости от массы и размера. К настоящему моменту подсистемы скоплений открыты и, в разной степени, изучены в нескольких сотнях галактик (Уитмор, 2003; Ларсен, 2006). Многие исследователи внегалактических звёздных скоплений полагают, что разделение изучаемых объектов на рассеянные и шаровые утратило смысл, так как во множестве галактик обнаружены подсистемы скоплений, которые по внешнему виду и массе подобны ШЗС Млечного Пути, но по возрасту и химическому составу похожи на РЗС нашей Галактики. Исследования, о которых пойдёт речь в настоящей работе, касаются только галактических объектов, где граница между РЗС и ШЗС хорошо заметна: две подсистемы различаются, прежде всего, своим пространственным распределением в Галактике, возрастом и содержанием тяжёлых элементов, а также массой, размерами, кинематическими параметрами. Связано это с тем, что в современную эпоху в
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