Physics of auroral phenomena : proceedings of the 35th Annual seminar, Apatity, 28 Februaru – 02 March, 2012 / [ed. board: A. G. Yahnin, A. A. Mochalov]. - Апатиты : Издательство Кольского научного центра РАН, 2012. - 187 с. : ил., табл.

“P h y sics o f A u roral P h en om en a ”, Proc. XXXV A n n u al Sem inar, A p a tity, p p . 1 0 7 -1 1 0 , 2 0 1 2 © Kola Science Centre, Russian Academy of Science, 2012 Polar Geophysical Institute GLOBAL DISTRIBUTION OF AURORAL LUMINOSITY INFERRED FROM THE AURORAL PRECIPITATION MODEL A.S. Kirillov, V.G. Vorobjev, O.I. Yagodkina, Yu.V. Katkalov (Polar Geophysical Institute, Apatity, Murmansk region, Russia) Abstract. The Auroral Precipitation Model (http://apm.pgia.ru/) was used to calculate the global distribution of the auroral luminosity in visible and UVI spectral ranges. Integral intensities of N2LBH bands near 170.0 nm, 1NG N2+ at 391.4 nm, (01) 557.7 nm, and the IPG N2band near 669.0 nm have been calculated. To calculate (OI) 557.7 nm intensity the production of 0 ( ‘S) in the electron energy transfer process N2(A3I ll+) + 0 (3P), the dissociative recombination, auroral electron impact and the production of electronically excited N2 by auroral electron impact were taken into account. A good agreement was revealed by comparison of the LBH global distribution observed by spacecraft UV imagers and calculated from the model. Introduction Empirical models of global distribution of precipitating particles are very convenient to use for studying (monitoring and the forecast) characteristics of auroral luminosity in different spectral region during magnetospheric disturbances. The first attempt to create a planetary model of auroral luminosity has been undertaken by Ivanov et al. [1993]. These authors used the model by Spiro et al. [1982] in which the electron precipitation pattern was developed from AE-C and AE-D spacecraft observations for four magnetic activity intervals. In this model (and in later models also) Kp and one hour averaged AE indexes were used as a level of magnetic activity. However, the time of the spacecraft pass through the auroral zone is only a few minutes that is why such models can provide only a rough estimation of the planetary distribution of auroral precipitation characteristics. In the present work to calculate the planetary distribution of auroral luminosity we used the Auroral Precipitation Model (АРМ) which is available on the PGI website http://apm.pgia.ru/ [Vorobjev and Yagodkina, 2005, 2007]. АРМ was developed on the base of statistical treatment of DMSP F6 and F7 spacecraft observations. This model at a specified level of magnetic activity allows us to receive a global distribution of the average electron energy and the energy flux in different precipitating zones. The АРМ precipitation pattern is a function of Dst and 5-min averaged AL indexes. Modelling o f emission intensities The model of the electronic kinetics of molecular nitrogen in auroral upper atmosphere in this work is similar to the models of Kirillov [2008, 2010, 2011a]. We consider five triplet A3EU+, B3n g, W3AU, B,3ZU“, С3П„ and three singlet a1Su_, a'llg, w!Au electronically excited states of N2. A main difference in the model consists in a neglecting of molecular collisions for the B3IIg, W3AU, B'3SU~ and a''Eu', a’l l g, w'Au states. Here we have included the following processes of the excitation and quenching of electronically excited N2molecules: 1. The electronic excitation by auroral primary and secondary electron impact. The method of "excitation energy costs" was suggested by Gordiets and Konovalov [1991], Sergienko and Ivanov [1993] where rates of the processes can be calculated using the value of the energy dissipated by auroral electrons in 1 cm3 [Kirillov et al., 1984]. 2. The spontaneous radiative transitions with the emissions of bands of first positive group (IPG), Wu-Benesch system (WB), afterglow system (AG), second positive group (2PG), Vegard-Kaplan system (VK) for triplet states and with the emissions of McFarland (MF), Ogawa-Tanaka-Wilkinson-Mulliken (OTWM) and Lyman-Birge- Hopfield (LBH) bands. Einstein coefficients for radiational spontaneous transitions are taken according to Gilmore et al. [ 1992] and Kirillov [2011a]. 3. The quenching of the A32 u+(v=0-6), W3Au(v=0), a,1Su (v=0,l), a‘n g(v=0) states in collisions with N2, 0 2, О atmospheric components. We neglect the quenching for another vibrational levels of the W3AU, a''Zu", a’l l g states and for all vibrational levels of the В3Пе, B,3I U_, С3ПШw'Au states because of high spontaneous radiative rates in comparison with collisional ones at the altitudes of upper atmosphere. The quenching rate coefficients by N2and 0 2 molecules are taken according to quantum-chemical calculations by Kirillov [2008, 201 lb,с]. The quenching rate coefficients by atomic oxygen are taken according to [Thomas and Kaufman , 1985] for the A3ZU+ state and [Gudipati et al., 2002; Khachatrian et al., 2003] for the a'1^ - and a‘n g states. It is supposed that the quenching rate of the W3Au,v=0 level by О is the same as for the A3Eu\v=0 level. The solving of corresponding equations allows us to calculate vibrational populations N Yv of triplet states. The emission of 669.0 nm band of IPG is related with spontaneous radiative transition with B3n g,v=5 and A3L„+,v'=2. So the intensity of the band 669.0 nm can be calculated by the equation ^ 669.0 = ^ 669 . 0 '[N2(B n g,v— 5)] (1) 107