This paper investigates the possibility that the particular location of flare production sites in an active region is intimately connected to the production of type III radio bursts as well as centimetric and hard X-ray events.
For the few active regions analysed (viz. McMath 8863, 8905, 8907 and 8921) it is shown that even a crude statistical test is sufficient in revealing significant differences concerning the emissions of these radiations by flares located in various flare production sites. In particular, flares located outside the general bipolar pattern of the active region are characterized by a higher type III flare association rate ( >~ 50 %) than those taking place inside of it ( ~< 20 %). Centimetric and hard X-ray events are more likely to be expected in connection with flares located inside strong magnetic fields arising from well developed sunspots. Such results are pointing out that the concept of 'flare production sites' is important not only in relation with the Ha flare activity but also in relation with the non-thermal emissions accompanying the flares.
Probably this is due to changing magnetic configuration from one flare site to the other.
* Equipe de recherche Associ~e du CNRS no. 306.