- McEnery, JE;
- Atkins, R;
- Benbow, W;
- Berley, D;
- Chen, ML;
- Coyne, DG;
- Dingus, BL;
- Dorfan, DE;
- Ellsworth, RW;
- Evans, D;
- Falcone, A;
- Fleysher, L;
- Fleysher, R;
- Gisler, G;
- Goodman, JA;
- Haines, TJ;
- Hoffman, CM;
- Hugenberger, S;
- Kelley, LA;
- Leonor, I;
- McConnell, M;
- McCullough, JF;
- Miller, RS;
- Mincer, AI;
- Morales, MF;
- Nemethy, P;
- Ryan, JM;
- Shen, B;
- Shoup, A;
- Sinnis, C;
- Smith, AJ;
- Sullivan, GW;
- Tumer, T;
- Wang, K;
- Wascko, MO;
- Westerhoff, S;
- Williams, DA;
- Yang, T;
- Yodh, GB
Milagrito, a detector sensitive to gamma-rays at TeV energies, monitored the
northern sky during the period February 1997 through May 1998. With a large
field of view and high duty cycle, this instrument was used to perform a search
for TeV counterparts to gamma-ray bursts. Within the Milagrito field of view 54
gamma-ray bursts at keV energies were observed by the Burst And Transient
Satellite Experiment (BATSE) aboard the Compton Gamma-Ray Observatory. This
paper describes the results of a preliminary analysis to search for TeV
emission correlated with BATSE detected bursts. Milagrito detected an excess of
events coincident both spatially and temporally with GRB 970417a, with chance
probability $2.8 \times 10^{-5}$ within the BATSE error radius. No other
significant correlations were detected. Since 54 bursts were examined the
chance probability of observing an excess with this significance in any of
these bursts is $1.5 \times 10^{-3}$. The statistical aspects and physical
implications of this result are discussed.