Главная     Введение     Выжить во Вселенной    
Inhabited Sky
    News@Sky     Астрофотография     Коллекция     Форум     Blog New!     Помощь     Пресса     Войти  

HD 44327


Оглавление

Изображения

Загрузить ваше изображение

DSS Images   Other Images


Публикации по объекту

New periodic variables from the Hipparcos epoch photometry
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.

The chemical evolution of the solar neighborhood. I - A bias-free reduction technique and data sample
The possible ways of measuring the age-metallicity relation for thegalactic disk in the neighborhood of the sun are discussed. It is shownthat the use of a field star sample chosen on the basis of effectivetemperature introduces a bias which results in a monotonic increase inthe metal abundance of the disk with time. However, if theage-metallicity relation for the disk can be shown to satisfy certaincriteria, the bias introduced in such a sample can be neglected: thegalactic disk apparently satisfies the criteria. It is concluded that asample analyzed through the use of uvby and H(beta) photometry inconjunction with a self-consistent set of theoretical isochronesprovides the least biased, most accurate estimate of the age-metallicityrelation for the disk.

Добавить новую статью


Внешние ссылки

  • - Внешних ссылок не найдено -
Добавить внешнюю ссылку


Группы:


Наблюдательные данные и астрометрия

Созвездие:Столовая Гора
Прямое восхождение:06h07m05.22s
Склонение:-81°03'47.4"
Видимая звёздная величина:7.123
Расстояние:161.812 парсек
Собственное движение RA:2.9
Собственное движение Dec:32.5
B-T magnitude:7.448
V-T magnitude:7.15

Каталоги и обозначения:
Собственные имена   (Edit)
HD 1989HD 44327
TYCHO-2 2000TYC 9391-877-1
USNO-A2.0USNO-A2 0075-01112281
HIPHIP 28993

→ Запросить дополнительные каталоги и обозначения от VizieR