It's not every day you get to help determine a fundamental constant of nature and a new phenomenon in particle physics. But an international team of scientists believes they have done just that, at an underground site near Daya Bay's nuclear plants.
A team of scientists from Hong Kong, the mainland and other countries - of which I am a member - has measured subtle changes in the behaviour of one of nature's most elusive particle: the neutrino.
This information is a key that will help researchers unlock one of the universe's great mysteries: why the universe is dominated by matter rather than balanced equally with antimatter.
Before you finish reading this sentence, hundreds of trillions of neutrinos produced in the centre of the sun will have penetrated your body without leaving any trace. Among the elementary particles - basic building blocks of all matter - neutrinos have always been the most mysterious.
They carry some mass and energy, but they barely interact at all; to a neutrino, you, I, the earth and even the sun are all transparent.
One of the Daya Bay Reactor neutrino experiment's detectors, with 20 tonnes of detecting materials, managed to 'catch' only about 700 neutrinos per day out of the vast flood - 10 to the power of 22 -that was passing through it from the reactors.