We have examined the radio emission characteristics of the micro-quasar GRSÂ 1915 + 105 during its X-ray emission states as classified by Belloni et al .
( 2000 ) .
We find that the radio emission is high during the \chi _ { 1 } and \chi _ { 3 } states ( the radio “ plateau ” state ) and also during the \beta and \theta states when X-ray soft dips are present in the X-ray light curve .
For all the other X-ray states we find that the radio emission is low ( < 20 mJy at 2.25 GHz ) .
This result supports the suggestion made by Naik et al .
( 2000 ) that the radio flares are caused by a series of X-ray dip events .
To further confirm this result , we have made a systematic study of all the PCA RXTE observations for those days when a radio flare was present .
We find 11 such observations and find that all of them are of class \beta , \theta or \chi .
Further , we have classified all the RXTE PCA observations obtained from 1996 November to 2000 February ( when the radio data is available ) and confirm that the radio flux , on an average , is much higher during the states \beta , \theta and \chi .
Based on these results , we argue that the radio flares are caused by the X-ray dips in the source .