IBS to Verify Long-held Controversies around Dark Matters (December 6)
- IBS underground experiment group to verify no signals of WIMP, dark-matter candidates
- Succeed in production of detector with increased sensitivity, collect data disproving the experiment of DAMA, Italy
□ COSINE-100 collaboration* led by Institute for Basic Science (IBS) underground experiment group opened the door in verifying long-held controversies surrounding dark matter.
* COSINE-100 collaboration: global joint research group created to conduct COSINE experiments of dark matter exploration (In this research, 50 scientists from 15 institutes from home and abroad took part.)
o The research team independently developed lab equipment for detecting dark matters and succeeded in collecting data which can refute the only evidence that WIMP, a leading dark-matter candidate has.
* WIMP (Weakly Interaction Massive Particle): WIMP refers to heavy particles having weak interactions and the idea first came into being in the posthumous paper of the deceased Dr. Whisoh Lee in 1977.
o The Ministry of Science and ICT (MSIT) and IBS announced the research outcomes were published in the online Nature (IF 42.351) at 3am of December 6 (Korean local time).
□ Dark matter, which makes up about 26.8%% of the universe has not been identified yet.
o While discovery of dark matter draws a lot of attention from academia, which almost regards this as equivalent to winning Nobel prize, the only case of finding traces of dark matter has been DArkMAtter(DAMA) experiment of particle physics laboratory in Italy.
o Since the first experiment in 1998, DAMA team has claimed for twenty years that they have captured WIMP signals of dark matter. However, controversies have remained whether signals observed by DAMA are real dark matters, as this has not been validated by other research teams afterwards.
□ Since 2016, IBS underground research group has started to conduct COSINE-100 experiment* at the 700m deep-underground laboratory located in Yangyang, Gangwon Province, as a way to verify experiments of DAMA team.
* COSINE-100 experiment: an experiment to identify the existence of dark matter based on photon emission from the collisions of dark matter and crystals having high purity
o So far, outstanding global research teams have failed to simulate experiment exactly the same as DAMA, as they had difficulty in acquiring manufacturing skills of crystals having high purity and realizing high shield performance. COSINE-100 collaboration research group was successful in independently producing detectors using the same crystals as the DAMA team.
o A stable detection environment compared to DAMA team has been created. By deploying a double shield design which has added liquid scintillator to solid shield, outside signal has been reduced while radiation made inside crystals decreased. Also, technologies that can remove unnecessary signals with AI has been added by deploying machine learning models.
o This paper was written based on the results of analyzing data collected by COSINE-100 detector from the early 59.5 days (2016.10.20.~12.29).
□ Data collected from early experiments (‘16.10.20.~12.29, for 59.5 days) of COSINE-100 experiment research group proposed the possibility that signals discovered by DAMA team might not come from dark matter.
o Deputy Head Hyunsoo Lee of the research team stated, “the discovery of dark matter is a remarkable event that can have a huge impact on all of the knowledge we have regarding physics. A detector that can perfectly simulate DAMA experiment has been independently developed, so starting to conduct independent experiments alone drew attention from academia.”
o In addition, the research team expects to secure additional data in the future, so that they can either completely verify or contradict the claim made by DAMA within the next five years.