クラブパルサーの強いプラズマ渦巻からナノ秒の電波が爆発する
関連する実験動画
Updated: May 6, 2026

11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
16.9K
T H Hankins1, J S Kern, J C Weatherall
1Physics Department, New Mexico Tech, Socorro, New Mexico 87801, USA. thankins@aoc.nrao.edu
Nature
|March 14, 2003
まとめ
研究者らは,ナノパルスと呼ばれる,クランブパルサーからの微小で明るいラジオバーストを発見しました. これまでに検出された最小の銀河外物体は,パルサーの放出に関する特定のプラズマモデルをサポートしています.
科学分野:
- 天文学と天体物理学について
- パルサー物理学 パルサー物理学
- プラズマ物理学 プラズマ物理学
背景:
- クラブパルサーは珍しい,非常に明るい"巨大"パルスを発し,その起源や一般的なパルサー発射メカニズムについて決定的な説明はありません.
- パルサー電波発射メカニズムに関する既存のモデルは,一貫した発射の時間構造によって区別されています.
研究 の 目的:
- クラブパルサーからの巨大パルサーの性質を調査するために.
- パルサー発射機構の競合するモデルをテストするために.
主な方法:
- カラブパルサーからの巨大無線パルスの観測と分析.
- 巨大パルス内のサブパルス構造の高時間解像度検出.
主要な成果:
- カラブパルサーの巨大パルスの中で,孤立した,高度に極化した,2ナノ秒のサブパルスを発見した.
- これらのサブパルスは,1メートル未満のプラズマ構造から発生し,太陽系外で検出された最小の天体を表しています.
- これらは,これまで観測された中で最も明るく輝く一時的な無線源です.
結論:
- 観測されたナノパルスは,パルサー磁気圏のプラズマ-渦巻波のパケットの崩壊によって最もよく説明されます.
- この発見は,パルサー放射の特定の理論モデルを強く支持しています.
関連する概念動画
Atomic Nuclei: Larmor Precession Frequency
3.5K
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession,...
3.5K
Atomic Nuclei: Magnetic Resonance
1.3K
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
1.3K
NMR Spectrometers: Radiofrequency Pulses and Pulse Sequences
1.8K
A pulse is a short burst of radio waves distributed over a range of frequencies that simultaneously excites all the nuclei in the sample. Upon passing a radio frequency pulse along the x-axis, the nuclei absorb energy corresponding to their Larmor frequencies and achieve resonance. This shifts the net magnetization vector from the z-axis toward the transverse plane. This angle of rotation of the magnetization vector, or the flip angle, is proportional to the duration and intensity of the pulse.
1.8K
Electromagnetic Waves
10.3K
James Clerk Maxwell formulated a single theory combining all the electric and magnetic effects scientists knew during that time, calling the phenomena his theory predicted “Electromagnetic waves”. He brought together all the work that had been done by brilliant physicists such as Oersted, Coulomb, Gauss, and Faraday and added his own insights to develop the overarching theory of electromagnetism. Maxwell’s equations, combined with the Lorentz force law, encompass all the laws...
10.3K
Electromagnetic Waves in Matter
2.8K
Electromagnetic waves can travel in the vacuum as well as in matter. For example light, which is an electromagnetic wave, can travel through air, water, or glass.
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium,...
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium,...
2.8K
Momentum And Radiation Pressure
1.8K
An object absorbing an electromagnetic wave would experience a force in the direction of propagation of the wave. This force occurs because electromagnetic waves contain and transport momentum. The force accounts for the wave's radiation pressure exerted on the object. Maxwell's prediction was confirmed in 1903 by Nichols and Hull by precisely measuring radiation pressures with a torsion balance. The measuring instrument had mirrors suspended from a fiber kept inside a glass container.
1.8K

