First Detection of Low-frequency Striae in Interplanetary Type III Radio Bursts

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F25%3A00635631" target="_blank" >RIV/68378289:_____/25:00635631 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/25:10510432

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.3847/2041-8213/add688" target="_blank" >https://iopscience.iop.org/article/10.3847/2041-8213/add688</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3847/2041-8213/add688" target="_blank" >10.3847/2041-8213/add688</a>

Jazyk výsledku

angličtina

Název v původním jazyce

First Detection of Low-frequency Striae in Interplanetary Type III Radio Bursts

Popis výsledku v původním jazyce

We report the first detection of type III solar radio burst striae in the 30-80 kHz range, observed by the Cluster-4 spacecraft during an exceptionally quiet solar period. These low-frequency fine structures, which drift slowly in frequency and exhibit narrow bandwidths, provide a novel diagnostic of plasma processes in the inner heliosphere. The detected striae, interpreted as fundamental plasma emission, exhibit a frequency drift rate of 0.328 Hz s-1 and a bandwidth of 1.3 kHz. By combining high-resolution radio observations with well-calibrated in situ electron velocity distribution function data from the Wind spacecraft, we characterized the plasma properties of the burst source region near 0.32 au. Our analysis estimates relative density fluctuations, at the effective turbulence scale length, as approximately 3.4% (inferred from striae bandwidths), 0.62% (from intensity fluctuations), and 3.5% (from a heliocentric distance-based empirical model). These findings offer critical insights into small-scale density inhomogeneities and turbulence that affect electron beam propagation. This study underscores the potential of combining well-calibrated in situ electron data with radio burst measurements to probe the physical conditions of the solar wind and to refine our understanding of solar radio bursts across a broad frequency range.

Název v anglickém jazyce

First Detection of Low-frequency Striae in Interplanetary Type III Radio Bursts

Popis výsledku anglicky

We report the first detection of type III solar radio burst striae in the 30-80 kHz range, observed by the Cluster-4 spacecraft during an exceptionally quiet solar period. These low-frequency fine structures, which drift slowly in frequency and exhibit narrow bandwidths, provide a novel diagnostic of plasma processes in the inner heliosphere. The detected striae, interpreted as fundamental plasma emission, exhibit a frequency drift rate of 0.328 Hz s-1 and a bandwidth of 1.3 kHz. By combining high-resolution radio observations with well-calibrated in situ electron velocity distribution function data from the Wind spacecraft, we characterized the plasma properties of the burst source region near 0.32 au. Our analysis estimates relative density fluctuations, at the effective turbulence scale length, as approximately 3.4% (inferred from striae bandwidths), 0.62% (from intensity fluctuations), and 3.5% (from a heliocentric distance-based empirical model). These findings offer critical insights into small-scale density inhomogeneities and turbulence that affect electron beam propagation. This study underscores the potential of combining well-calibrated in situ electron data with radio burst measurements to probe the physical conditions of the solar wind and to refine our understanding of solar radio bursts across a broad frequency range.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GA22-10775S" target="_blank" >GA22-10775S: Analýza plazmových vln a dopadů prachových částic pozorovaných přístrojem RPW-TDS na sondě Solar Orbiter</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astrophysical Journal Letters

ISSN

2041-8205

e-ISSN

2041-8213

Svazek periodika

985

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

L27

Kód UT WoS článku

001492421700001

EID výsledku v databázi Scopus

2-s2.0-105005784428