STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI

Cho, I. -H.; Cho, K. -S.; Bong, S. -C.; Lim, E. -K.; Kim, R. -S.; Choi, S.; Kim, Y. -H.

doi:10.1088/0004-637X/811/1/49

Title: STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI

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Abstract

We carried out an extensive statistical study of the properties of pores and sunspots, and investigated the relationship among their physical parameters such as size, intensity, magnetic field, and the line-of-sight (LOS) velocity in the umbrae. For this, we classified 9881 samples into three groups of pores, transitional sunspots, and mature sunspots. As a result, (1) we find that the total magnetic flux inside the umbra of pores, transitional sunspots, and mature sunspots increases proportionally to the powers of the area and the power indices in the three groups significantly differ from each other. (2) The umbral area distribution of each group shows a Gaussian distribution and they are clearly separated, displaying three distinct peak values. All of the quantities significantly overlap among the three groups. (3) The umbral intensity shows a rapid decrease with increasing area, and their magnetic field strength shows a rapid increase with decreasing intensity. (4) The LOS velocity in pores is predominantly redshifted and its magnitude decreases with increasing magnetic field strength. The decreasing trend becomes nearly constant with marginal blueshift in the case of mature sunspots. The dispersion of LOS velocities in mature sunspots is significantly suppressed compared to pores. From our results, wemore »« less

Authors:

Cho, I. -H.; Cho, K. -S.; Bong, S. -C.; Lim, E. -K.; Kim, R. -S.; Choi, S.; Kim, Y. -H. ^[1]

Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of)

Publication Date:: Sun Sep 20 00:00:00 EDT 2015

OSTI Identifier:: 22525392

Resource Type:: Journal Article

Journal Name:: Astrophysical Journal

Additional Journal Information:: Journal Volume: 811; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; GAUSS FUNCTION; MAGNETIC FIELDS; MAGNETIC FLUX; PHOTOSPHERE; RED SHIFT; SUN; SUNSPOTS; VELOCITY

Citation Formats


                    Cho, I. -H., Cho, K. -S., Bong, S. -C., Lim, E. -K., Kim, R. -S., Choi, S., Kim, Y. -H., and Yurchyshyn, V., E-mail: kscho@kasi.re.kr. STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI.  United States: N. p., 2015. 
        Web.  doi:10.1088/0004-637X/811/1/49.

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                    Cho, I. -H., Cho, K. -S., Bong, S. -C., Lim, E. -K., Kim, R. -S., Choi, S., Kim, Y. -H., & Yurchyshyn, V., E-mail: kscho@kasi.re.kr. STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI.  United States.  https://doi.org/10.1088/0004-637X/811/1/49

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                    Cho, I. -H., Cho, K. -S., Bong, S. -C., Lim, E. -K., Kim, R. -S., Choi, S., Kim, Y. -H., and Yurchyshyn, V., E-mail: kscho@kasi.re.kr. 2015.  
        "STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI".  United States.  https://doi.org/10.1088/0004-637X/811/1/49.

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@article{osti_22525392,

  title        = {STATISTICAL COMPARISON BETWEEN PORES AND SUNSPOTS BY USING SDO/HMI},

  author       = {Cho, I. -H. and Cho, K. -S. and Bong, S. -C. and Lim, E. -K. and Kim, R. -S. and Choi, S. and Kim, Y. -H. and Yurchyshyn, V., E-mail: kscho@kasi.re.kr},

  abstractNote = {We carried out an extensive statistical study of the properties of pores and sunspots, and investigated the relationship among their physical parameters such as size, intensity, magnetic field, and the line-of-sight (LOS) velocity in the umbrae. For this, we classified 9881 samples into three groups of pores, transitional sunspots, and mature sunspots. As a result, (1) we find that the total magnetic flux inside the umbra of pores, transitional sunspots, and mature sunspots increases proportionally to the powers of the area and the power indices in the three groups significantly differ from each other. (2) The umbral area distribution of each group shows a Gaussian distribution and they are clearly separated, displaying three distinct peak values. All of the quantities significantly overlap among the three groups. (3) The umbral intensity shows a rapid decrease with increasing area, and their magnetic field strength shows a rapid increase with decreasing intensity. (4) The LOS velocity in pores is predominantly redshifted and its magnitude decreases with increasing magnetic field strength. The decreasing trend becomes nearly constant with marginal blueshift in the case of mature sunspots. The dispersion of LOS velocities in mature sunspots is significantly suppressed compared to pores. From our results, we conclude that the three groups have different characteristics in their area, intensity, magnetic field, and LOS velocity as well in their relationships.},

  doi          = {10.1088/0004-637X/811/1/49},

  url          = {https://www.osti.gov/biblio/22525392},
  journal      = {Astrophysical Journal},

  issn         = {0004-637X},

  number       = 1,

  volume       = 811,

  place        = {United States},

  year         = {Sun Sep 20 00:00:00 EDT 2015},

  month        = {Sun Sep 20 00:00:00 EDT 2015}

}

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