We report on the search for Gamma Ray Bursts ( GRBs ) in the energy range 1-100 GeV in coincidence with the prompt emission detected by satellites using the Astrophysical Radiation with Ground-based Observatory at YangBaJing ( ARGO-YBJ ) air shower detector .
Thanks to its mountain location ( Yangbajing , Tibet , P.R .
China , 4300 m a.s.l .
) , active surface ( \sim 6700 m ^ { 2 } of Resistive Plate Chambers ) , and large field of view ( \sim 2 sr , limited only by the atmospheric absorption ) , the ARGO-YBJ air shower detector is particularly suitable for the detection of unpredictable and short duration events such as GRBs .
The search is carried out using the “ single particle technique ” , i.e .
counting all the particles hitting the detector without measurement of the energy and arrival direction of the primary gamma rays .

Between 2004 December 17 and 2009 April 7 , 81 GRBs detected by satellites occurred within the field of view of ARGO-YBJ ( zenith angle \theta \leq 45 ^ { \circ } ) .
It was possible to examine 62 of these for > 1 GeV counterpart in the ARGO-YBJ data finding no statistically significant emission .
With a lack of detected spectra in this energy range fluence upper limits are profitable , especially when the redshift is known and the correction for the extragalactic absorption can be considered .
The obtained fluence upper limits reach values as low as 10 ^ { -5 } erg cm ^ { -2 } in the 1-100 GeV energy region . Besides this individual search for a higher energy counterpart , a statistical study of the stack of all the GRBs both in time and in phase was made , looking for a common feature in the GRB high energy emission .
No significant signal has been detected .