{
  "id": "2211.01140",
  "version": "v1",
  "published": "2022-11-02T14:19:09.000Z",
  "updated": "2022-11-02T14:19:09.000Z",
  "title": "Ripples and Rush-to-the-Poles in the photospheric magnetic field",
  "authors": [
    "Elena S. Vernova",
    "Marta I. Tyasto",
    "Dmitrii G. Baranov"
  ],
  "comment": "15 pages, 12 figures",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "The distribution of magnetic fields of positive and negative polarities over the surface of the Sun was studied on the basis of synoptic maps NSO Kitt Peak (1978-2016). To emphasize the contribution of weak fields the following transformation of synoptic maps was made: for each synoptic map only magnetic fields with modulus less than 5 G (|B| < 5 G) were left unchanged on each synoptic map while larger or smaller fields were replaced by the corresponding limiting values +5 G or -5 G. Cyclic variations of the magnetic field polarity have been observed associated with two types of magnetic field flows in the photosphere. Rush-to-the-Poles (RTTP) form near the maximum of solar activity and have the same sign as the following sunspots. The lifetime of RTTP is 3 yrs, during which time they drift from latitudes 30 - 40 deg. to the pole, causing the polarity change of the Sun's polar field. We studied another type of variations which has the form of series of flows with individual flows of 0.5-1 yr and with alternating polarity (ripples). Ripples are located in time between two RTTP and drift from the equator to the latitudes of 50 deg. Magnetic field variations were considered in 6 time intervals along the latitudes +33 deg. in the northern and -33 deg. in the southern hemispheres. The time change of the field strength was approximated by the sinusoidal function. The period of variation of ripples was 1.1 yr for the N-hemisphere and 1.3 yr for the S-hemisphere. The amplitude of variation was higher for the time intervals where the polar field had a positive sign. Within the same flow, fields of positive and negative signs developed in anti-phase.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-11-02T14:19:09.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "photospheric magnetic field",
      "rush-to-the-poles",
      "synoptic maps nso kitt peak",
      "time intervals",
      "polar field"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 15,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}