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在红移 z = 0.7 的高丰度
J K Webb1, R F Carswell, K M Lanzetta
1School of Physics, University of New South Wales, Sydney, Australia.
Nature
|July 17, 1997
概括
原始到 (D/H) 的测量结果不一致. 这项研究报告了新的中间红移D/H值,表明早期宇宙中存在显著的不均性.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 核物理 核物理 核物理
背景情况:
- 原始与比 (D/H) p是宇宙质密度参数omegaB的关键诊断指标.
- 现有的高红移D/H测量显示出显著的差异,可能是由于观测不确定性.
- 不一致的D/H值对宇宙学模型和银河系化学进化构成挑战.
研究的目的:
- 报告D/H比率在中间红移 (z = 0.7010) 的第一个测量.
- 为了研究原始D/H丰度中的潜在不均性.
- 提供一个值,可以帮助解决宇宙参数估计中的差异.
主要方法:
- 选择了中间红移 (z = 0.7010) 的气体云,以最大限度地减少观测不确定性.
- 在选定的气体云中测量了与的比率 (D/H).
- 在现有的高红移测量和宇宙学模型的背景下分析了D/H值.
主要成果:
- 在z = 0.7010.10时测定了 (2.0 +/- 0.5) x 10[-4]的D/H值.
- 这个测量值位于高红移测量所观察到的范围的上端.
- 这些结果与其他观察结果相结合,表明 (D/H) p中可能存在至少十倍的不均性.
结论:
- 这些发现支持了原始丰度存在显著不均性的假设.
- 这种不均性对D/H测量作为宇宙学探测器的解释有影响.
- 需要进一步测量以确认 (D/H) p变化的程度和影响.
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