在434微米处检测星际一氧化碳的亚毫米异质检测
概括
天文学家使用新型射线计在猎户座分子云中检测到一氧化碳. 产生这种排放的气体在光学上很薄,温度高于180K.
科学领域:
- 天文学和天体物理学
- 亚毫米光谱学 细毫米光谱学
- 分子云研究 分子云研究
背景情况:
- 在天文观测中,亚毫米异体放射仪至关重要.
- 了解像猎户座这样的分子云需要详细的光谱分析.
研究的目的:
- 为天文应用开发和使用一种新型的亚毫米异体放射仪.
- 检测和描述一氧化碳在猎户座分子云中的旋转转变.
主要方法:
- 开发了一种望远镜上装的放射仪,配有光激光局部振荡器和肖特基二极管混合器.
- 高频和空间分辨率测量.
- 在434微米处检测到一氧化碳的J = 6 --> 5旋转过渡.
主要成果:
- 开发的辐射计实现了噪声温度低于4000 K (双侧带).
- 在猎户座分子云中成功检测到一氧化碳过渡.
- 测量结果显示,排放源于一个光学上薄的气体,其温度超过180K.
结论:
- 新的辐射计对于天文观测是有效的,提供高灵敏度和分辨率.
- 猎户座的分子云中含有大量热的,光学上薄的气体,其痕迹是由一氧化碳.
相关概念视频
Atomic Emission Spectroscopy: Instrumentation
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.
Atomic Emission Spectroscopy: Interference
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,...
¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
IR Spectroscopy: Molecular Vibration Overview
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Attenuated Total Reflectance (ATR) Infrared Spectroscopy: Overview
Attenuated total reflectance (ATR) infrared spectroscopy is a powerful analytical technique used to study the composition of materials. It is widely employed in chemistry, materials science, forensic science, and other fields where sample characterization is required. ATR has several advantages over traditional transmission IR spectroscopy, including the requirement of little to no sample preparation and the ability to analyze a wide range of samples.
The ATR process begins by directing a beam...
The ATR process begins by directing a beam...
Atomic Emission Spectroscopy: Lab
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...


