From Natalie Wolchover at Quanta:
One of the oldest and biggest experiments hunting for dark matter particles, DAMA is alone in claiming to see them. It purports to pick up on rare interactions between the hypothesized particles and ordinary atoms. But if these dalliances between the visible and invisible worlds really do produce DAMA’s data, several other experiments would probably also have detected dark matter by now. They have not.
Late last month, Rita Bernabei of the University of Rome Tor Vergata, DAMA’s longtime leader, presented the results of an additional six years of measurements. She reported that DAMA’s signal looks as strong as ever. But researchers not involved with the experiment have since raised serious arguments against dark matter as the signal’s source.More.
Will dark matter turn out to be the ether or phlogiston of our time?
See also: Dark matter find due to “less than perfect” optics
If dark matter is everywhere why isn’t it detected?
Dark matter skeptics wanted
Fermi researcher: Dark matter field is in a state of “major disruption.” Rob Sheldon comments