相关实验视频
Updated: Jul 12, 2026

06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
双类星0957+561:在6厘米波长的无线电研究
概括
双类星体0957+561可能是两个独立的类星体,而不是一个引力透镜. 它们相似的光学和无线电特性表明,它们在相似的初始条件下同时形成.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
背景情况:
- 天体0957+561,称为光学双类星,已被理论化为一个重力透镜成两个图像的单个物体.
- 引力透镜是一种现象,大质量物体扭曲时空,扭曲背景光源的光.
研究的目的:
- 为了研究光学双类星0957+561.1.的性质.
- 为了区分引力透镜假设和两个不同的类星体的可能性.
主要方法:
- 利用国家射电天文台的非常大阵列 (VLA) 来创建0957+561.1.的详细无线电地图.
- 分析了光学和无线电数据,以比较观察到的源的特征.
主要成果:
- 无线电地图揭示了与光学图像一致的未解决的源头,以及复杂的扩展无线电发射.
- 虽然不能完全排除引力透镜,但观察到的无线电结构更符合两个独立的类星体.
- 这两个明显类星体的光学和无线电特性具有很强的相似性.
结论:
- 0957+561的复杂无线电结构更有可能由两个单独的类星体解释.
- 类似的特性表明,这两个类星体可能是在相似的初始条件下同时形成的.
更多相关视频
09:38Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
11:27Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2
Published on: December 8, 2016
相关概念视频
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...
Emission Spectra
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.
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,...
Doppler Effect - II
The Doppler effect has several practical, real-world applications. For instance, meteorologists use Doppler radars to interpret weather events based on the Doppler effect. Typically, a transmitter emits radio waves at a specific frequency toward the sky from a weather station. The radio waves bounce off the clouds and precipitation and travel back to the weather station. The radio frequency of the waves reflected back to the station appears to decrease if the clouds or precipitation are moving...
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: Overview
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...