ARCHIVAL SEARCHES FOR TRANSIENT OPTICAL-EMISSION IN THE ERROR BOX OF THE 1991 JANUARY 22 GAMMA-RAY BURST

We present here the results of a study carried out at the Harvard Coll ege Observatory Plate Collection. We examined 3995 plates covering the error box of the gamma-ray burst GRB 910122, over a time span of 90 y r (from 1889 to 1979). The total exposure time is similar to 0.55 yr. No convincing evidence of optical transient emission was found within the GRB 910122 TPN error box. However, a possible OT was found outside the GRB 910122 error box. Optical ground based observations have reve aled a V similar to 22.3 object consistent with the position of the ne w object. The colours of the object are typical of a K7/M0 star or a r eddened galaxy, which could have caused the OT, but the fact that the object is far away from the GRB error box makes both events unrelated.