Stocks are up in midday trading as investors await the Federal Reserve’s assessment of the U.S. economy. The Dow is up 76 points, the Nasdaq is up 2.41 points and the S&P is up 5 points.

Here’s six stocks rallying in midday trading.

Radvision Ltd. (NASDAQ:RVSN) is up 16.51% in midday trading at $9.81. RVSN has traded 903 thousand shares so far today, way above its daily average volume of just 43 thousands shares. On Monday, GP Synergy chose Radvision for video collaboration programs. Since the start of the week, RVSN is up more than $2 per share. The company has a market cap of 180.69 million.

Cabot Microelectronics Corp. (NASDAQ:CCMP) is up 16.59% today at $46.88. CCMP has traded 855 thousand shares so far today, 8 times its daily average volume. CCMP announced a higher dividend and a share repurchase program this year. Cabot Microelectronics has a market cap of 1.06 billion.

RAM Energy Resources, Inc. (NASDAQ:RAM) is up 9.91% in midday trading at $1.22. RAM has traded 450 thousand shares so far today, more than 3 times its daily average. The company has a market cap of 94.89 million.

GeoEye, Inc. (NASDAQ:GEOY) is up 10.47% at $21.00 today. GEOY has traded 302 thousand shares so far today, 20 thousand shares more than its daily average. GEOY is up more than $2 a share since Friday. GeoEye has a market cap of 461.25 million.

Pandora Media, Inc. (NYSE:P) is up 6.75% in midday trading at $10.60. P has traded 2 million shares so far today, more than double its daily average. Pandora listenership increase 13-25% in the the 10 largest U.S. radio markets. Pandora Media has a market cap of 1.71 billion.

Dynegy Inc. (NYSE:DYN) is up 6.16% at $2.93 in midday trading. DYN has traded 1.4 million shares so far today and trades 359.54 million shares a day on average. DYN is bouncing back today after the stock fell from $3 to the $2.70s yesterday. The company has a market cap of 358.31 million.