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Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
从档案数据中,IIn型超新星的红移z大约为2的超新星
Jeff Cooke1, Mark Sullivan, Elizabeth J Barton
1Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, California 92697-4574, USA. cooke@uci.edu
Nature
|July 10, 2009
概括
三个IIn型超新星被发现在高红移使用一种新的方法. 这一发现支持了巨大的恒星形成模型,并挑战了恒星初始质量函数演变的理论.
科学领域:
- 天文学 天文学
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
背景情况:
- 观察到的Ia型超新星的红移值为z ≈1.7,II型超新星的红移值为z ≈0.7.
- 类型IIn超新星,大质量恒星的发光核心崩爆炸,在紫外线中很亮,表现出强烈的辐射线,使得在高红移 (z ≈ 2) 时的检测成为可能.
研究的目的:
- 报告发现了三颗光谱学证实的IIn型超新星在高红移的发现.
- 利用利用IIn型超新星独特特性用于高红移检测的方法.
- 在高红移时探测大质量恒星形成.
主要方法:
- 使用专门的检测方法进行档案数据分析.
- 超新星类型和红移的光谱确认.
- 利用IIn型超新星的紫外线亮度和排放线特征.
主要成果:
- 发现了三颗IIn型超新星,它们的红移z=0.808,2.013和2.357.
- 观察到的IIn型超新星的数量与当地的恒星初始质量函数一致.
- 这些发现挑战了不断演变的初始质量函数的模型.
结论:
- IIn型超新星是早期宇宙中大质量恒星形成的宝贵探测器.
- 目前的观测与标准的恒星初始质量函数模型保持一致.
- 需要进一步的研究来使观测与不断发展的初始质量函数理论相协调.
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