Related Experiment Video
Updated: Oct 6, 2025
11:20
Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
15.1K
NuSTAR Observation of Energy Release in 11 Solar Microflares
Jessie Duncan1, Lindsay Glesener1, Brian W Grefenstette2
1University of Minnesota, Minneapolis, MN, USA.
The Astrophysical Journal
|January 17, 2022
Summary
This study analyzed 11 solar microflares using the Nuclear Spectroscopic Telescope Array (NuSTAR), revealing they share properties with larger solar flares. Findings suggest microflares often involve hotter plasma, offering new insights into solar energy release.
Area of Science:
- * Solar physics
- * Astrophysics
- * Plasma physics
Background:
- * Solar flares are explosive magnetic energy releases.
- * Hard X-ray (HXR) emission provides insight into flare energy release mechanisms.
- * The Nuclear Spectroscopic Telescope Array (NuSTAR) offers enhanced sensitivity for HXR observations.
Purpose of the Study:
- * To analyze 11 microflares observed by NuSTAR.
- * To compare microflare properties with larger solar flares.
- * To investigate the origin of HXR emission in microflares.
Main Methods:
- * Observation and analysis of 11 microflares using NuSTAR data.
- * Examination of temporal, spatial, and energetic properties.
- * Spectral fitting to model HXR emission.
Main Results:
- * Microflares exhibited impulsive time profiles and earlier HXR peaks at higher energies, similar to large flares.
- * Spatial analysis showed no complexity, with emission centroids consistent across energy ranges.
- * Spectral fitting revealed a high-energy excess, attributed to hotter plasma in most events and accelerated particles in one.
Conclusions:
- * Microflares share characteristics with larger solar flares, indicating common energy release processes.
- * The study provides the first collective analysis of a significant number of NuSTAR microflare events.
- * A new correction method for NuSTAR gain variations in low livetime regimes was established for future solar studies.
Keywords:
Non-thermal radiation sources (1119)Solar flare spectra (1982)Solar flares (1496)Solar physics (1476)Solar x-ray flares (1816)The Sun (1693)More Related Videos
Related Concept Videos
02:45Nuclear Fusion
32.3K
The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons.
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
32.3K
01:20Atomic Emission Spectroscopy: Overview
2.8K
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...
2.8K
02:39Emission Spectra
69.6K
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.
69.6K
01:29Atomic Emission Spectroscopy: Lab
273
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...
273
01:22Atomic Emission Spectroscopy: Instrumentation
682
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.
682
01:30Atomic Emission Spectroscopy: Interference
308
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,...
308