@InProceedings{BrumAbdBatSanBar:2004:LoIoCo,
               author = "Brum, Christiano Garnett Marques and Abdu, Mangalathayil Ali and 
                         Batista, Inez Staciarini and Santos, Pedrina Morais dos Santos and 
                         Barros, Lucyana Pereira",
                title = "Lower ionosphere cosmic noise absorption responses to the 
                         interplanetary magnetic field behavior in the south atlantic 
                         magnetic anomaly and sub-auroral regions",
            booktitle = "Proceedings...",
                 year = "2004",
         organization = "COSPAR Scientific Assembly, 35.",
             abstract = "The interplanetary magnetic field (IMF) plays an important role in 
                         the cosmic ray flux modulation that reaches the lower ionosphere, 
                         which is one of the main sources of the ionization in these 
                         regions. In this work, it is presented data analysis results 
                         obtained from riometers operating at 30 MHz over Cachoeira 
                         Paulista (located at South Atlantic Magnetic Anomaly (SAMA) - 
                         connected to an antenna pointed to the zenith direction, 22.50oS; 
                         45.00oW) and the Brazilian Antarctic Station - EACF (connected to 
                         an antenna pointed to the zenith and geomagnetic west directions, 
                         62.56oS; 58.39oW) during almost one complete solar cycle 
                         (1989-1996). Previous results have shown that there is a strong 
                         correlation between the cosmic noise absorption (CNA) behavior and 
                         the IMF. Basically, the sub-auroral region presents a decrease in 
                         the CNA with the increase of the IMF intensity, while in the SAMA 
                         region, for the same IMF conditions, it was registered an 
                         increase. Related to the IMF direction, the greater values of CNA 
                         are present when the IMF is pointed to the south and to the east 
                         for EACF and AMAS regions, respectively. The results of these data 
                         analysis are discussed and the galactic cosmic noise absorption is 
                         computed by using the geomagnetic activity (geomagnetic field 
                         values) to show the relationship between CNA and IMF behavior.",
  conference-location = "Paris, France",
      conference-year = "18-25 july",
                label = "self-archiving-INPE-MCTIC-GOV-BR",
             language = "en",
           targetfile = "brum_lower.pdf",
        urlaccessdate = "19 maio 2024"
}