Related Experiment Video
Updated: Feb 25, 2026
14:18
Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
12.0K
Significant and variable linear polarization during the prompt optical flash of GRB 160625B
E Troja1,2, V M Lipunov3,4, C G Mundell5
1Department of Astronomy, University of Maryland, College Park, Maryland 20742-4111, USA.
Nature
|July 28, 2017
Summary
We detected significant, variable linear polarization in a prompt optical flash from a gamma-ray burst (GRB). This finding reveals insights into the magnetic field structure within relativistic jets close to the central black hole.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Black hole physics
Background:
- Stellar-mass black holes launch relativistic jets, powering gamma-ray bursts (GRBs).
- Measuring radiation polarization probes magnetic fields within these jets.
- Previous polarization studies of GRBs yielded controversial results, especially during the prompt emission phase.
Purpose of the Study:
- To investigate the magnetic field configuration during the prompt phase of a gamma-ray burst (GRB).
- To understand the origin of prompt GRB radiation by analyzing polarization properties.
Main Methods:
- Polarimetric observations of a prompt optical flash accompanying GRB 160625B.
- Analysis of linear polarization degree and variability during the prompt emission phase.
Main Results:
- Detection of substantial (8.3 ± 0.8 per cent) and variable linear polarization in the prompt optical flash.
- The results probe the magnetic field structure closer to the central black hole, at an early jet stage.
Conclusions:
- The prompt GRB phase is generated by fast-cooling synchrotron radiation.
- A large-scale magnetic field, advected from the black hole and distorted by dissipation, permeates the jet.
Related Concept Videos
01:01Group Polarization
39.2K
Group polarization is the strengthening of an original group attitude following the discussion of views within a group (Teger & Pruitt, 1967). That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition.
39.2K
01:26Variables Affecting Phosphorescence and Fluorescence
1.7K
Fluorescence and phosphorescence are essential phenomena in fields like analytical chemistry, biological imaging, and materials science, where they detect molecular properties and visualize cellular structures. Understanding the variables that influence these luminescent behaviors is crucial for maximizing accuracy and efficiency in their applications. These variables can broadly be grouped into chemical structure, solvent properties, and external conditions, each playing a distinct role in...
1.7K
01:29Potential Due to a Polarized Object
838
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
838
01:25Fluorescence and Phosphorescence: Instrumentation
1.7K
Fluorometers and spectrofluorometers are two types of instruments used for measuring molecular fluorescence. These instruments differ in how they select excitation and emission wavelengths and the type of light sources they utilize. Fluorometers use absorption interference filters to choose excitation and emission wavelengths. The excitation source in a fluorometer is typically a low-pressure mercury vapor lamp that emits intense lines distributed throughout the ultraviolet and visible regions.
1.7K
01:15Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)
1.1K
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT) is an advanced Nuclear Magnetic Resonance (NMR) technique specifically designed to detect and enhance the signals of low-abundance nuclei, such as carbon-13 and nitrogen-15, in small molecules. The fundamental principle behind INEPT is the transfer of polarization from a more abundant and highly polarizable nucleus, typically hydrogen-1, to the low-abundance nucleus of interest. This process effectively boosts the NMR signal of the...
1.1K
01:23Photoluminescence: Fluorescence and Phosphorescence
4.1K
Photoluminescence is a process where a molecule absorbs light energy and re-emits it in the form of light. This phenomenon occurs when a substance absorbs photons, promoting its electrons to higher energy level excited states, followed by a relaxation process in which the electrons return to their original ground state energy levels and emit light. Photoluminescence is widely observed in various materials, including semiconductors, and organic and inorganic compounds.
A pair of electrons in a...
A pair of electrons in a...
4.1K