Yield is dependent on many things. veg time, strain, temp, humidity, plant health, training, et cetera. that being said an average grower could yield 250-600 grams under a 600 watt hps.
Looks like you're wasting a lot of light.
For one, you could probably bring that hood down a bit closer to your plant because you have what appears to be a cool tube.
Second, You have no reflective material around her. You could definitely increase your yield if you directed more of that light towards the plant.
If your gonna do 1 plant under that light you might want to veg a long time and supercrop or lst it. looks like you'll get maybe 2 oz off her. Just guesstimating.
yah just cuz you have a way more light than needed for 1 plant that size does not mean it will blow up huge with budds. that plant looks only about 3 feet tall... where would a pound even go? haha