Baking

Ready for baking: the vacuum system will be heated to approximately 350 degrees Celcius. This causes the outgasing of many elements attached to the internal vacuum surface and these gases are extracted using turbo molecular pumps. the vacuum chamber is wrapped with heating tapes with heat the chamber when a controlled current is applied. A total of 10 heating tapers are used and thermocouples placed in various places allow us to measure temperature and adjust the heater currents accordingly. the entire vacuum chamber is covered with several layers of tinfoil to trap the heat and allow efficient heating of the chamber (a total of 150 m of tinfoil was used)

The vacuum system consists of two separate vacuum chambers (2-D MOT and BEC chambers) separated by a differential pumping hole. This hole is large enough to allow atoms to pass from one chamber to another but is small enough to allow a differential pressure of three orders of magnitude between the two chambers. a UHV pressure of 10^-3 mbar is expected on the BEC side with a pressure of 10^-8 mbar on the 2-D MOT side (with the Rb in the chamber). the Rb is supplied using a 1 mg Rb ampule which outgases and fills the 2-D MOT chamber. an ion pump on each side will maintain the vacuum once it is achieved.  a titanium sublimation pump on the BEC side can be used to decrease the pressure by an order of magnitude in case the pressure increases over time!

Vacuum system complete... but there is a leak somewhere :-(

Vacuum System Design

A CAD diagram for our vacuum system. We are currently only missing the cone section and a few bake-out bits and pieces

Vacuum system takes shape

part of vacuum build and pumped to 5*10^-8 mbar. We need to wait 2-3 more week (depending on the ordering system) for more things to arrive before we can begin baking

Vacuum system arrives

After a long wait, the vacuum system has arrived... vacuum construction begins today
A few more bits and pieces to arrive and we can start bakeout

Xmas break status:

• Cooling laser SAS set up
• Repumping laser SAS setup
• Tapered amplifier injected
• Small part of vacuum setup and leak tested

The rest of the vacuum system will arrive at the end of January
lots more orders to come through as well (AOMs, optics, PSUs)

SARRbBEC: the beginning

Step 1: destroy the previous set up and start again.... Mission complete!!!!!!!