|Introduction|| Data policy and
We express our deepest gratitude to the colleagues at the collaborating observatories for participating in the daily routine observations and putting the necessary material at our disposal. The contributing observatories taking white-light full disk observations were: Abastumani Astrophysical Observatory (Georgia), Ebro Observatory (Spain), Helwan Observatory (Egypt), Kanzelhoehe Solar Observatory (Austria), Kiev University Observatory (Ukraine), Kislovodsk Solar Observing Station of Pulkovo Observatory (Russia), Ussuriysk Astrophysical Observatory, Far-Eastern Branch of the Russian Academy of Sciences (Russia) , Kodaikanal Solar Observatory (India), Mauna Loa Solar Observatory (USA), Mount Wilson Observatory (USA), San Fernando Observatory (USA), Solar Observatory of National Astronomical Observatory of Japan (Mitaka/Tokyo, Japan), Rome Astronomical Observatory (Italy), Tashkent Observatory (Uzbekistan), and Royal Observatory of Belgium (USET data/image of Uccle/Brussels, Belgium), Royal Greenwich Observatory (Herstmonceux, UK), Valasske Mezirici Observatory (Czech Republic).
We thank the INAF-Catania Astrophysical Observatory for its full-disk
The Mount Wilson
white-light full disk scans are available
thanks to the Mt.
Wilson Solar Photographic Archive Digitization
by the National Science Foundation under Grant No.0236682. The
magnetic database includes data from the synoptic program at the
150-Foot Solar Tower of the Mount
Observatory. The Mt. Wilson
150-Foot Solar Tower is operated by UCLA, with funding from NASA, ONR
and NSF, under agreement with the Mt. Wilson Institute.
The Na-D filtergrams of Kanzelhoehe Solar Observatory are available by courtesy of the Central European Solar ARchives (CESAR).
Space-born full disk quasi-continuum images and LOS magnetograms obtained by the Michelson Doppler Imager (MDI) on the board of Solar and Heliospheric Observatory (SOHO) are used by courtesy of the SOHO/MDI research group at Stanford University. SOHO (Solar and Heliospheric Observatory) is a mission of international cooperation between ESA and NASA.
The SDO/HMI images are available by courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
We thank the NSO/Kitt Peak
Observatory for the full disk LOS
with the 512-Channel Magnetograph, Spectromagnetograph and SOLIS VSM.
Peak magnetic data used here are produced cooperatively by NSF/NOAO,
NASA/GSFC and NOAA/SEL.
We acknowledge the courtesy of editors of Solnechnie Dannie solar catalogue, who permit the use of magnetic polarity drawings observed by several contributing observatories: Crimean Astrophysical Observatory, Sayan Observatory of Institute of Solar-Terrestrial Physics of Siberian Department of Russian Academy of Sciences, Pulkovo Observatory and its Kislovodsk Solar Observing Station, Ussuriysk Astrophysical Observatory (Ussurijsk Solar Service Station) , Astronomical Observatory of Ural State University, Institute of Geophysics and Astronomy of Cuba.This work utilizes data obtained by the Global Oscillation Network Group (GONG) Program, managed by the National Solar Observatory, which is operated by AURA, Inc. under a cooperative agreement with the National Science Foundation. The data were acquired by instruments operated by the Big Bear Solar Observatory, High Altitude Observatory, Learmonth Solar Observatory, Udaipur Solar Observatory, Instituto de Astrofisica de Canarias, and Cerro Tololo Inter-American Observatory.