12276"The Quest for Dark Matter" --World's Leading Experts Discuss Their Search
- Apr 9 5:14 PMURL to a report on the dark matter conference from The Daily Galaxy blogChris
"The discovery of dark matter means we would have identified the dominant form of matter in the universe that seeded structure and led to galaxies, solar systems and planets, and ultimately to our Earth with intelligent life. In late February, dark matter hunters from around the world gathered at the University of California, Los Angeles for “Dark Matter 2014” --the unknown stuff that makes up more than a quarter of the universe yet remains a mystery.The annual conference is one of the largest of its kind aimed at discussing the latest progress in the quest to identify dark matter. Nearly 160 people attended, including renowned physicists from institutions across the United States and Europe, as well as from Japan, China and Canada.
So where does the hunt stand? Between sessions, three leading physicists at the conference spent an hour discussing its biggest highlights and prospects for future progress.
Blas Cabrera – Professor of Physics at Stanford University, and Member of the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) at Stanford. Spokesperson for the SuperCDMS dark matter experiment. Dan Hooper – Scientist in the Theoretical Astrophysics Group at the Fermi National Accelerator Laboratory, Associate Professor in the Department of Astronomy and Astrophysics at the University of Chicago, and Senior Member of the Kavli Institute for Cosmological Physics (KICP) at UChicago. Tim Tait – Professor of Physics and Astronomy at the University of California Irvine, and Member of UC Irvine’s Theoretical Particle Physics Group.
The following is an edited transcript of the discussion led by the Kavli Foundation at Stanford University. The Kavli Foundation supports leading science aimed at understanding the origin, structure and composition of the cosmos.
THE KAVLI FOUNDATION: Almost everyone at the conference seems to think we’re finally on the path toward figuring out what dark matter is. After 80 years of being in the “dark,” what are we hearing at this meeting to explain the optimism?
Why are scientists optimistic about figuring out what dark matter is?
What is the latest for researchers looking for evidence of supersymmetry, which could reveal the nature of dark matter?
Has anything discussed at this meeting convinced you which approach will be the first to identify dark matter?
What would a confirmed detection of dark matter really mean for what we know about the universe?
BLAS CABRERA: This conference has highlighted the progression of larger and larger experiments with remarkable advances in sensitivity. What we’re looking for is evidence of a dark matter particle, and the leading idea for what it might be is something called a weakly interacting massive particle, or WIMP. We believe the WIMP interacts with ordinary matter only very rarely, but we have hints from a few experiments that might be evidence for WIMPs.
Separately at this conference, we heard about improved calibrations of last fall’s results from LUX, the Large Underground Xenon detector that now leads the world in sensitivity for WIMPs above the mass of six protons – a proton being the nucleus of a single hydrogen atom. Under a standard interpretation of the data, the LUX team has ruled out a range of low-end masses for the dark matter particle, another major advance because it does not see potential detections reported by other experiments and further narrows the possibilities for how massive the WIMP might be.
Finally, Dan [Hooper] also gave a remarkable presentation here about another effort: to indirectly detect dark matter by studying radiation coming from the center of the Milky Way galaxy. He reported the possibility of a strong dark matter signal, and I would say that was also one of the highlights of the conference because it provides us with some of the strongest evidence so far of a dark matter detection in space. Dan can explain.
In the image below, Gamma-ray photons seen emanating from the center of the Milky Way galaxy are consistent with the intriguing possibility that dark-matter particles are annihilating each other in space, according to research conducted by UC Irvine astrophysicists. Analyzing data collected between August 2008 and June 2012 from NASA’s Fermi Gamma-ray Space Telescope orbiting Earth, the team found more gamma-ray photons coming from the Milky Way galactic center than they had expected, based on previous scientific models.