It’s all over for Clover
Apr 2, 2009 2 comments
The UK has cancelled funding for an experiment that, if built, would have searched for the signatures of gravitational waves in the Comic Microwave Background (CMB).
The cancellation of the £4.78m Clover project, a collaboration between Cardiff, Oxford, Manchester and Cambridge universities, is now threatening redundancies as funding runs out. The decision was made by the Science and Technology Facilities Council (STFC) at a council meeting last week.
The Clover telescope, to have been sited in the Atacama Desert, Chile, was designed to search for gravitational waves by looking at the polarization of photons from the CMB as they scattered off free electrons when stars first formed and re-ionized the surrounding gas of the early universe.
Although gravitational waves have never been directly measured, it is in principle possible to tease out their existence by mapping in detail the temperature and polarization of photons in the CMB.
Until now it has only been possible to measure the temperature fluctuations using, for example, the space-based Wilkinson Microwave Anisotropy Probe (WMAP), which was launched in 2003.
Direct link to gravitational waves
However, around 1% of the CMB photons are polarized and these polarizations take the form of so-called “E-modes”, which WMAP also measured, and “B-modes”, which gives information about the orientation of the polarization. The signal from B-modes, which have not been measured to date, are 100 times weaker than E-modes and are directly linked to the existence of gravitational waves.
The Clover project was designed to detect these B-modes by two independent radio-telescopes, one operating at 95 GHz with the other operating at both 150 and 225 GHz. However, after its council meeting on 24 March, the STFC decided to cancel funding for the project. The funding council had already spent £4.5m on Clover, but the project was almost 60% over budget and needed almost £3m to finish construction.
I am sure there will be more redundancies as a result of this decision Peter Coles, Cardiff University
Despite the project being deemed “high importance” in the STFC’s review of facilities last July, in a statement the STFC said, “[the] council was assured that the science to be addressed by Clover remained first rate, [but] the additional funding needed could not be made available in the current financial situation.”
The cancellation now threatens redundancies at the four universities who are part of the project. “There are some people at Cardiff who only have a few months of funding left,” says theorist Peter Coles , from Cardiff University, who had planned to analyse data from Clover. “And I am sure there will be more redundancies as a result of this decision.”
Not all doom and gloom
However, it is not all doom and gloom for the search to detect gravitational waves. The US-led QUIET telescope in Chile, an international collaboration consisting of 12 partners including the universities of Manchester and Oxford, is also designed to detect B-modes and will start taking data soon.
“Another reason why the STFC has pulled the plug could be because Clover is facing intense competition in the race to be the first to detect gravitational waves,” says Coles, “but I am very disappointed that the STFC seems to be walking away from fundamental science.”
About the author
Michael Banks is News Editor of Physics World magazine