[C ii] 158-μm发射来自受阻莱曼-阿尔法系统的主体星系
Marcel Neeleman1, Nissim Kanekar2, J Xavier Prochaska3
1University of California Observatories-Lick Observatory, University of California, Santa Cruz, CA 95064, USA. marcel@ucsc.edu.
Science (New York, N.Y.)
|March 25, 2017
概括
天文学家检测到来自高红移吸收的星系的[C ii]线和尘埃辐射. 这些星系类似于巨大的恒星形成系统,
科学领域:
- 天文学与天体物理学
- 宇宙学
背景情况:
- 研究高红移星系周围的气体对于理解宇宙进化至关重要.
- 与背景类星体相比,这些星系的观测具有挑战性.
研究的目的:
- 识别和描述具有高红移 (z ~ 4) 的吸收线系统的星系.
- 研究这些星系及其周围气体的物理性质.
主要方法:
- 使用阿塔卡马大毫米/亚毫米阵列 (ALMA).
- 检测[C ii]158μm线和尘埃连续性的排放.
主要成果:
- 成功检测到两个星系在z~4的[Cii]和尘埃连续辐射.
- 这些星系与高金属性吸收系统有关.
- 宿主星系表现出与巨大的恒星形成星系相似的特性.
结论:
- 这项研究证实了超越这些星系的星际环境的缩中性气体储备.
- 这为早期星系的环银河系介质提供了新的见解.
相关概念视频
02:39Emission Spectra
77.2K
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
77.2K
01:20Atomic Emission Spectroscopy: Overview
4.0K
Atomic emission spectroscopy (AES) is an analytical technique used to determine the elemental composition of a sample by analyzing the light emitted from excited atoms. In AES, atoms in a sample are excited to higher energy levels by thermal energy from high-temperature sources, such as plasma, arcs, or sparks. When these excited atoms return to lower energy states, they emit light at specific wavelengths characteristic of each element. The resulting atomic emission spectrum, which consists of...
4.0K
01:29Atomic Emission Spectroscopy: Lab
739
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
739
01:22Atomic Emission Spectroscopy: Instrumentation
1.4K
The instrumentation of atomic emission spectrometry (AES) involves various components, including atomization devices that convert samples into gas-phase atoms and ions. There are two main types of atomization devices: continuous and discrete atomizers. Continuous atomizers, like plasmas and flames, introduce samples in a constant stream, while discrete atomizers inject individual samples using syringes or autosamplers. The most common discrete atomizer is the electrothermal atomizer.
1.4K
01:30Atomic Emission Spectroscopy: Interference
706
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
706
01:12Interaction of EM Radiation with Matter: Spectroscopy
3.6K
Electromagnetic (EM) radiation can be considered an oscillating electric and magnetic field propagating through a medium that can interact with matter in its path. The electric field in the radiation can interact with electrical charges in the atoms or molecules in the matter. On the other hand, the magnetic field can interact with the magnetic field in the atomic nucleus. The study of the interaction between electromagnetic radiation and matter is termed spectroscopy. Spectroscopy is the study...
3.6K