edu.ucar.opensky::articles:44013 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T17:44:00.021326 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.net/ark:/85065/d7g73k6r Observation and modeling of small spatial structures of solar radio noise storms using the uGMRT 2025-08-01T00:00:00Z publication https://n2t.net/ark:/85065/d7g73k6r https://doi.org/10.1007/s11207-025-02519-8 Mondal, S. author Zhang 张, PeiJin 沛锦 author Kansabanik, Devojyoti author Oberoi, D. author Pearce, G. author UCAR/NCAR - Library publisher One of the most commonly observed solar radio sources in the metric and decametric wavelengths is the solar noise storm. These are generally associated with active regions and are believed to be powered by the plasma emission mechanism. Since plasma emission is emitted primarily at the fundamental and harmonic of the local plasma frequency, it is significantly affected by density inhomogeneities in the solar corona. The source can become significantly scatter-broadened due to the multi-path propagation caused by refraction from the density inhomogeneities. Past observational and theoretical estimates suggest some minimum observable source size in the solar corona. The details of this limit, however, depend on the modeling approach and details of the coronal turbulence model chosen. Hence pushing the minimum observable source size to smaller values can help constrain the plasma environment of the observed sources. In this work, we for the first time, use data from the upgraded Giant Metrewave Radio Telescope in the 250&#8201;&#8211;&#8201;500&#160;MHz band, to determine multiple instances of very small-scale structures in the noise storms. We also find that these structures are stable over timescales of 15&#8201;&#8211;&#8201;30 minutes. By comparing the past observations of type III radio bursts and noise storms, we hypothesize that the primary reason behind the detection of these small sources in noise storm is due to the local environment of the noise storm. We also build an illustrative model and propose some conditions under which the minimum observable source size predicted by theoretical models, can be lowered significantly. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication <span style="font-family:Arial;font-size:10pt;font-style:normal;font-weight:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span> None eng geoscientificInformation