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Title: SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY

Abstract

In this work, we take advantage of 11 different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of photospheric magnetic structures. We find that, when taken separately, different databases are better fitted by different distributions (as has been reported previously in the literature). However, we find that all our databases can be reconciled by the simple application of a proportionality constant, and that, in reality, different databases are sampling different parts of a composite distribution. This composite distribution is made up by linear combination of Weibull and log-normal distributions—where a pure Weibull (log-normal) characterizes the distribution of structures with fluxes below (above) 10{sup 21}Mx (10{sup 22}Mx). Additionally, we demonstrate that the Weibull distribution shows the expected linear behavior of a power-law distribution (when extended to smaller fluxes), making our results compatible with the results of Parnell et al. We propose that this is evidence of two separate mechanisms giving rise to visible structures on the photosphere: one directly connected to the global component of the dynamo (and the generation of bipolar active regions), and the other with the small-scale component of the dynamo (and the fragmentation of magnetic structures due to their interaction with turbulentmore » convection)« less

Authors:
; ; ;  [1];  [2];  [3];  [4];  [5]; ;  [6];  [7];  [8];  [9];  [10];  [11]
  1. Department of Physics, Montana State University, Bozeman, MT 59717 (United States)
  2. Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)
  3. Kislovodsk Mountain Astronomical Station of the Pulkovo Observatory, Kislovodsk 357700 (Russian Federation)
  4. Pulkovo Astronomical Observatory, Russian Academy of Sciences, St. Petersburg 196140 (Russian Federation)
  5. National Solar Observatory, Sunspot, NM 88349 (United States)
  6. San Fernando Observatory, Department of Physics and Astronomy, California State University Northridge, Northridge, CA 91330 (United States)
  7. Department of Mathematical Sciences, Durham University, South Road, Durham DH1 3LE (United Kingdom)
  8. National Solar Observatory, Tucson, AZ 85719 (United States)
  9. Institute for Astronomical, Terrestrial and Space Sciences (ICATE-CONICET), San Juan (Argentina)
  10. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
  11. Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303 (United States)
Publication Date:
OSTI Identifier:
22364203
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 800; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CONVECTION; MAGNETIC FIELD CONFIGURATIONS; MAGNETIC FIELDS; MAGNETIC FLUX; PHOTOSPHERE; SUN; SUNSPOTS

Citation Formats

Muñoz-Jaramillo, Andrés, Windmueller, John C., Amouzou, Ernest C., Longcope, Dana W., Senkpeil, Ryan R., Tlatov, Andrey G., Nagovitsyn, Yury A., Pevtsov, Alexei A., Chapman, Gary A., Cookson, Angela M., Yeates, Anthony R., Watson, Fraser T., Balmaceda, Laura A., DeLuca, Edward E., and Martens, Petrus C. H., E-mail: munoz@solar.physics.montana.edu. SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY. United States: N. p., 2015. Web. doi:10.1088/0004-637X/800/1/48.
Muñoz-Jaramillo, Andrés, Windmueller, John C., Amouzou, Ernest C., Longcope, Dana W., Senkpeil, Ryan R., Tlatov, Andrey G., Nagovitsyn, Yury A., Pevtsov, Alexei A., Chapman, Gary A., Cookson, Angela M., Yeates, Anthony R., Watson, Fraser T., Balmaceda, Laura A., DeLuca, Edward E., & Martens, Petrus C. H., E-mail: munoz@solar.physics.montana.edu. SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY. United States. doi:10.1088/0004-637X/800/1/48.
Muñoz-Jaramillo, Andrés, Windmueller, John C., Amouzou, Ernest C., Longcope, Dana W., Senkpeil, Ryan R., Tlatov, Andrey G., Nagovitsyn, Yury A., Pevtsov, Alexei A., Chapman, Gary A., Cookson, Angela M., Yeates, Anthony R., Watson, Fraser T., Balmaceda, Laura A., DeLuca, Edward E., and Martens, Petrus C. H., E-mail: munoz@solar.physics.montana.edu. Tue . "SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY". United States. doi:10.1088/0004-637X/800/1/48.
@article{osti_22364203,
title = {SMALL-SCALE AND GLOBAL DYNAMOS AND THE AREA AND FLUX DISTRIBUTIONS OF ACTIVE REGIONS, SUNSPOT GROUPS, AND SUNSPOTS: A MULTI-DATABASE STUDY},
author = {Muñoz-Jaramillo, Andrés and Windmueller, John C. and Amouzou, Ernest C. and Longcope, Dana W. and Senkpeil, Ryan R. and Tlatov, Andrey G. and Nagovitsyn, Yury A. and Pevtsov, Alexei A. and Chapman, Gary A. and Cookson, Angela M. and Yeates, Anthony R. and Watson, Fraser T. and Balmaceda, Laura A. and DeLuca, Edward E. and Martens, Petrus C. H., E-mail: munoz@solar.physics.montana.edu},
abstractNote = {In this work, we take advantage of 11 different sunspot group, sunspot, and active region databases to characterize the area and flux distributions of photospheric magnetic structures. We find that, when taken separately, different databases are better fitted by different distributions (as has been reported previously in the literature). However, we find that all our databases can be reconciled by the simple application of a proportionality constant, and that, in reality, different databases are sampling different parts of a composite distribution. This composite distribution is made up by linear combination of Weibull and log-normal distributions—where a pure Weibull (log-normal) characterizes the distribution of structures with fluxes below (above) 10{sup 21}Mx (10{sup 22}Mx). Additionally, we demonstrate that the Weibull distribution shows the expected linear behavior of a power-law distribution (when extended to smaller fluxes), making our results compatible with the results of Parnell et al. We propose that this is evidence of two separate mechanisms giving rise to visible structures on the photosphere: one directly connected to the global component of the dynamo (and the generation of bipolar active regions), and the other with the small-scale component of the dynamo (and the fragmentation of magnetic structures due to their interaction with turbulent convection)},
doi = {10.1088/0004-637X/800/1/48},
journal = {Astrophysical Journal},
number = 1,
volume = 800,
place = {United States},
year = {Tue Feb 10 00:00:00 EST 2015},
month = {Tue Feb 10 00:00:00 EST 2015}
}
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