Magnetic network elements in solar cycle 23

Jin Chunlan, cljin@nao.cas.cn, National Astronomical Observatories, Chinese Academy of Sciences
Wang Jingxiu, wangjx@nao.cas.cn, National Astronomical Observatories, Chinese Academy of Sciences

Abstract
In the report, we present our recent effort to understand the cyclic behavior of network magnetic elements based on the unique database from full-disk observation provided by Michelson Doppler Imager on board the Solar and Heliospheric Observatory (SOHO/MDI) in the interval including the entire cycle 23. The following results are unclosed. (1) The quiet regions dominate the solar magnetic flux for about 8 years in solar cycle 23, and from the solar minimum to maximum they contribute (0.94--1.44) X10^{23} Mx flux to the solar photosphere. In the entire cycle 23, the magnetic flux of the quiet regions is 1.12 times that of active regions. The occupation ratio of quiet region flux equally characterizes the course of a solar cycle. (2) With the increasing magnetic flux per element, the variations of numbers and total flux of the network elements show three-fold scenario: no-correlation, anti-correlation, and correlation with sunspots, respectively. The anti-correlated elements covering the range of (2.9 - 32.0) X10^{18} Mx occupy 77.2% of total element number and 37.4% of quiet Sun flux. (3) The anti-correlated elements show the broadest latitude distribution, and their time-latitude distribution is anti-correlated with that of sunspots; the correlated elements display the similar butterfly diagram of sunspots but with wider latitude distribution. These results seem to imply that the correlated elements are the debris of decayed sunspots, and the source of anti-correlated elements is modulated by sunspot magnetic field. We consider three possibilities of how to understand the anti-correlated elements.