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Title: Association of Plages with Sunspots: A Multi-Wavelength Study Using Kodaikanal Ca ii K and Greenwich Sunspot Area Data

Abstract

Plages are the magnetically active chromospheric structures prominently visible in the Ca ii K line (3933.67 Å). A plage may or may not be associated with a sunspot, which is a magnetic structure visible in the solar photosphere. In this study we explore this aspect of association of plages with sunspots using the newly digitized Kodaikanal Ca ii K plage data and the Greenwich sunspot area data. Instead of using the plage index or fractional plage area and its comparison with the sunspot number, we use, to our knowledge for the first time, the individual plage areas and compare them with the sunspot area time series. Our analysis shows that these two structures, formed in two different layers, are highly correlated with each other on a timescale comparable to the solar cycle. The area and the latitudinal distributions of plages are also similar to those of sunspots. Different area thresholdings on the “butterfly diagram” reveal that plages of area ≥4 arcmin{sup 2} are mostly associated with a sunspot in the photosphere. Apart from this, we found that the cyclic properties change when plages of different sizes are considered separately. These results may help us to better understand the generation andmore » evolution of the magnetic structures in different layers of the solar atmosphere.« less

Authors:
; ;  [1]
  1. Indian Institute of Astrophysics, Koramangala, Bangalore 560034 (India)
Publication Date:
OSTI Identifier:
22663955
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CALCIUM; COMPARATIVE EVALUATIONS; DISTRIBUTION; OSCILLATIONS; PHOTOSPHERE; PLAGES; POTASSIUM; SOLAR CYCLE; SPECTRA; STELLAR CHROMOSPHERES; SUN; SUNSPOTS; WAVELENGTHS

Citation Formats

Mandal, Sudip, Chatterjee, Subhamoy, and Banerjee, Dipankar, E-mail: sudip@iiap.res.in. Association of Plages with Sunspots: A Multi-Wavelength Study Using Kodaikanal Ca ii K and Greenwich Sunspot Area Data. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/2/158.
Mandal, Sudip, Chatterjee, Subhamoy, & Banerjee, Dipankar, E-mail: sudip@iiap.res.in. Association of Plages with Sunspots: A Multi-Wavelength Study Using Kodaikanal Ca ii K and Greenwich Sunspot Area Data. United States. doi:10.3847/1538-4357/835/2/158.
Mandal, Sudip, Chatterjee, Subhamoy, and Banerjee, Dipankar, E-mail: sudip@iiap.res.in. Wed . "Association of Plages with Sunspots: A Multi-Wavelength Study Using Kodaikanal Ca ii K and Greenwich Sunspot Area Data". United States. doi:10.3847/1538-4357/835/2/158.
@article{osti_22663955,
title = {Association of Plages with Sunspots: A Multi-Wavelength Study Using Kodaikanal Ca ii K and Greenwich Sunspot Area Data},
author = {Mandal, Sudip and Chatterjee, Subhamoy and Banerjee, Dipankar, E-mail: sudip@iiap.res.in},
abstractNote = {Plages are the magnetically active chromospheric structures prominently visible in the Ca ii K line (3933.67 Å). A plage may or may not be associated with a sunspot, which is a magnetic structure visible in the solar photosphere. In this study we explore this aspect of association of plages with sunspots using the newly digitized Kodaikanal Ca ii K plage data and the Greenwich sunspot area data. Instead of using the plage index or fractional plage area and its comparison with the sunspot number, we use, to our knowledge for the first time, the individual plage areas and compare them with the sunspot area time series. Our analysis shows that these two structures, formed in two different layers, are highly correlated with each other on a timescale comparable to the solar cycle. The area and the latitudinal distributions of plages are also similar to those of sunspots. Different area thresholdings on the “butterfly diagram” reveal that plages of area ≥4 arcmin{sup 2} are mostly associated with a sunspot in the photosphere. Apart from this, we found that the cyclic properties change when plages of different sizes are considered separately. These results may help us to better understand the generation and evolution of the magnetic structures in different layers of the solar atmosphere.},
doi = {10.3847/1538-4357/835/2/158},
journal = {Astrophysical Journal},
number = 2,
volume = 835,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}