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tokens: respectively (Kouveliotou et al. 1993 ; Mészáros 2006 ). While long GRBs are most likely associated with the collapse of massive stellar objects (Woosley 1993 ; MacFadyen Woosley 1999 ), the short ones are usually attributed to the merger of two neutron stars (Eichler et al. 1989 ; Paczynski 1990 ), or one neutron star with one black hole (Lattimer Schramm 1976 ; Lee Ramirez-Ruiz 2007 ). They are also potential sources responsible for the emission of ultrahigh-energy cosmic rays (Milgrom Usov 1995 ; Waxman 1995a , 1995b ; Dermer Humi 2001 ; Chakraborti et al. 2011 ), high-energy neutrinos (Waxman Bahcall 1997 ; Waxman 2000 ; Abbasi et al. 2012 ; Murase et al. 2013 ), and gravitational waves (Kobayashi Mészáros 2003 ; Corsi Mészáros 2009 ; Chen Holz 2013 ; Lasky Glampedakis 2016 ; Abbott et al. 2017 ). The study of GRBs has been prolific over the past decades (Zhang Meszaros 2004 ; Nakar 2007 ; Kouveliotou et al. 2012 ; D’Avanzo 2015 ). GRBs have opened a unique window into connecting the fields of stellar, interstellar, and intergalactic astronomy as well as cosmology. With the new generation of space-borne experiments, such as the Swift and Fermi observatories, high-energy observations of GRBs have entered a new era in the study of extragalactic background light (EBL; Ackermann et al. 2012 ; Desai et al. 2017 ) and the search for Lorentz invariance violation (LIV; Ellis et al. 2019 ; Lang et al. 2019 ; Wei 2019 ). As one example, GRB 130427A (Ackermann et al. 2014 ) was able to produce photons of up to 94 GeV in observations (126 GeV at the source after redshift correction, which accounts for the attenuation due to EBL). It is unknown up to what energy the spectrum extends, as present-day observations are limited by effective area in the case of space-based instruments. Ground-based detectors may prove to be an important compensator for GRB observation when γ -ray energy is above tens of GeV (Grupen Buvat 2011 ; Abeysekara et al. 2012 ; de Angelis 2016 ). Two types of experimental techniques are available for this purpose: imaging air Cerenkov telescopes (IACTs) and extended air shower (EAS) array. IACTs have better observational sensitivity to stable point sources due to their higher angular resolution and better background rejection power (Poggiani 2017 ). However, IACTs have a limited field of view, which makes them useful for follow-up observations. Moreover, the requirement of a safe slew time makes follow-up of real-time alerts difficult. Even when slew time is not an issue, a small field of view requires accurate pointing in the GRB direction. However, the error boxes provided by wide-field-of-view GRB monitors are usually large at alert time. Another disadvantage is that IACTs operate in good weather on moonless nights, which makes the duty cycle of IACTs only 10%–15% (Hinton 2009 ; Bigongiari 2016 ). A small field of view and low duty cycle make IACTs an inconvenient and inefficient instrument for GRB observation. While EAS arrays