Buy only above 15840 in spot, if any 15 min. candle close above. Wait for confirmation, First Nifty Should Close 15 Min. Candle above 15840 then it should retrace back to 15815 level then buy with SL of 15800 and see for higher target of 15950. One can short also if 15 min. candle doesn't close above 15840 then sell Near 15840 with SL of 15870. Look For the target of 15800 / 15780.