The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR...The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR NOAA 12411 was studied.Based on the continuum intensity images and vector magnetic field data with stray light correction from Solar Dynamics Observatory/Helioseismic and Magnetic Imager,the area,vector magnetic field and magnetic flux in the umbra and penumbra are calculated with time,respectively.Our main results are as follows:(1) The decay curves of the sunspot area in its umbra,penumbra,and whole sunspot take the appearance of Gaussian profiles.The area decay rates of the umbra,penumbra and whole sunspot are-1.56 MSH day^(-1),-12.61 MSH day^(-1) and-14.04 MSH day^(-1),respectively;(2) With the decay of the sunspot,the total magnetic field strength and the vertical component of the penumbra increase,and the magnetic field of the penumbra becomes more vertical.Meanwhile,the total magnetic field strength and vertical magnetic field strength for the umbra decrease,and the inclination angle changes slightly with an average value of about 20°;(3) The magnetic flux decay curves of the sunspot in its umbra,penumbra,and whole sunspot exhibit quadratic patterns,their magnetic flux decay rates of the umbra,penumbra and whole sunspot are-9.84 × 10^(19)Mx day^(-1),-1.59 × 10^(20)Mx day^(-1) and -2.60 × 10^(20)Mx day^(-1),respectively.The observation suggests that the penumbra may be transformed into the umbra,resulting in the increase of the average vertical magnetic field strength and the reduction of the inclination angle in the penumbra during the decay of the sunspot.展开更多
基金supported by the National Natural Science Foundation of China(11973084,11873087,12003066 and 11527804)Yunnan Key Laboratory of Solar Physics and Space Science under number 202205AG070009+5 种基金Yunnan Science Foundation of China under number:202201AT070194Youth Innovation Promotion Association,CAS(No.2019061)CAS“Light of West China”ProgramYunnan Science Foundation for Distinguished Young Scholars(No.202001AV070004)Key Research and Development Project of Yunnan Province under number 202003AD150019Young Elite Scientists Sponsorship Program by YNAST.9。
文摘The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR NOAA 12411 was studied.Based on the continuum intensity images and vector magnetic field data with stray light correction from Solar Dynamics Observatory/Helioseismic and Magnetic Imager,the area,vector magnetic field and magnetic flux in the umbra and penumbra are calculated with time,respectively.Our main results are as follows:(1) The decay curves of the sunspot area in its umbra,penumbra,and whole sunspot take the appearance of Gaussian profiles.The area decay rates of the umbra,penumbra and whole sunspot are-1.56 MSH day^(-1),-12.61 MSH day^(-1) and-14.04 MSH day^(-1),respectively;(2) With the decay of the sunspot,the total magnetic field strength and the vertical component of the penumbra increase,and the magnetic field of the penumbra becomes more vertical.Meanwhile,the total magnetic field strength and vertical magnetic field strength for the umbra decrease,and the inclination angle changes slightly with an average value of about 20°;(3) The magnetic flux decay curves of the sunspot in its umbra,penumbra,and whole sunspot exhibit quadratic patterns,their magnetic flux decay rates of the umbra,penumbra and whole sunspot are-9.84 × 10^(19)Mx day^(-1),-1.59 × 10^(20)Mx day^(-1) and -2.60 × 10^(20)Mx day^(-1),respectively.The observation suggests that the penumbra may be transformed into the umbra,resulting in the increase of the average vertical magnetic field strength and the reduction of the inclination angle in the penumbra during the decay of the sunspot.
