CoGeNT
TheCoGeNTexperiment has searched fordark matter.It uses a singlegermaniumcrystal (~100 grams[1]) as acryogenic detectorforWIMPparticles. CoGeNT has operated in theSoudan Underground Laboratorysince 2009.
Results
[edit]Their first announcement was an excess of events recorded after 56 days.[2]Juan Collar, who presented the results to a conference at the University of California, was quoted: "If it's real, we're looking at a very beautiful dark-matter signal".[2][3]
This signal conflicts with other searches that have failed to find any evidence, such asXENONandLUXbut appears to confirm results fromDAMA.
They observed an annual modulation in the event rate that could indicate light dark matter.[4]
The annual modulation has continued to be seen in 3 years of data.[1]
However more recent work has shown that the excess of events attributed to a tentative dark matter signal was in fact due to an underestimated background from surface events.[5]After accounting for this background there is no evidence for a signal in data from the CoGeNT experiment and no tension with null results from other experiments.[6][7]
References
[edit]- ^abEdwin Cartlidge (Jan 20, 2014)."CoGeNT gives further backing to annual dark-matter variation".
- ^abEric Hand (2010-02-26)."A CoGeNT result in the hunt for dark matter".Nature.Nature News.doi:10.1038/news.2010.97.
- ^C. E. Aalseth; CoGeNT collaboration (2011). "Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector".Physical Review Letters.106(13): 131301.arXiv:1002.4703.Bibcode:2011PhRvL.106m1301A.doi:10.1103/PhysRevLett.106.131301.PMID21517370.S2CID24822628.
- ^James Dacey (June 2011)."CoGeNT findings support dark-matter halo theory".physicsworld.Retrieved5 May2015.
- ^Davis, Jonathan; McCabe, Christopher; Boehm, Celine (August 2014). "Quantifying the evidence for Dark Matter in CoGeNT data".Journal of Cosmology and Astroparticle Physics.1408(8): 014.arXiv:1405.0495.Bibcode:2014JCAP...08..014D.doi:10.1088/1475-7516/2014/08/014.S2CID54532870.
- ^Aalseth, C.E. (5 Feb 2015). "Maximum Likelihood Signal Extraction Method Applied to 3.4 years of CoGeNT Data".arXiv:1401.6234[astro-ph.CO].
- ^Davis, Jonathan (June 12, 2015). "The Past and Future of Light Dark Matter Direct Detection".Int. J. Mod. Phys. A.30(15): 1530038.arXiv:1506.03924.Bibcode:2015IJMPA..3030038D.doi:10.1142/S0217751X15300380.S2CID119269304.