The Sensex from a low of 15,706, rebounded into the positive zone and touched a high of 15,862. The index is now up 57 points at 15,847.The NSE Nifty is up 27 points at 4,774.Reliance Energy (REL) has surged 3.5% to Rs 1,218. Hindalco has gained 2.3% at Rs 177.Mahindra & Mahindra has advanced 1.5% to Rs 617. Reliance and Maruti have added 1.3% each to Rs 2,450 and Rs 742, respectively.TCS, Reliance Communications and BHEL are up 1% each at Rs 887, Rs 502 and Rs 1,794, respectively.Infosys, ICICI Bank and Satyam have slipped 1% each to Rs 1,465, Rs 828 and Rs 423, respectively.