The cylindrical chamber (shown above) has a diameter of 40mm and has 24 fixed flanges of different diameters at different angles. This chamber was earlier used for plasma experiments with the picosecond laser chain and now used for experiments with the 2-beam laser.

Octogonal Chamber

The octogonal chamber (shown above) has a diameter of 70mm and has eight demountable flanges. Each flange can have upto three diagnostic ports. One chamber is used for plasma experiments with the picosecond laser chain and another identical chamber is used for experiments with Ti:sapphire laser.
All the three chambers are evacuated to a pressure of 10 ^-5 torr using turbo-molecular pumps.

Targets: Planar slabs ( or foils) of carbon, aluminium, silicon, magnesium, copper, lead (and other elements) are used as targets. In addition, specially made mix-Z targets are also used in some experiments. The targets are mounted on stepper motor controlled X-Y-Z translational stages. For short pulse experiments, gas puff system is used.

Focussing: Two types of focussing geometries are used:

1. Point Focus : (~100 micron dia spot)
   with a spherical lens ( f=400mm, 65mm dia)
2. Line Focus : (~100 micron x 5 mm )
   with cylindrical lenses (f= 450 mm, 550 mm, and 75 mm dia)
3. In addition, Off-axis parabola with 400mm focal length is used for focussing Ti:sa laser to a spot of 8 micron radius.

• 10 ¹¹ W/cm² to 10 ¹⁵ W/cm² for point focus with ps laser. This goes up to 10 ¹⁷ W/cm² with the TTT laser.
• Typically, 10 ¹² W/cm² for line focus with ns laser.
• 10 ¹⁸ W/cm² with Off-Axis parabola with the Ti:sapphire laser.

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