Editing Weakly interacting massive particle (section)

=== Recent limits ===

[[File:Direct Detection Constraints.png |frame|Figure 2: Plot showing the parameter space of dark matter particle mass and interaction cross section with nucleons. The LUX and SuperCDMS limits exclude the parameter space above the labelled curves. The CoGeNT and CRESST-II regions indicate regions which were previously thought to correspond to dark matter signals, but which were later explained with mundane sources. The DAMA and CDMS-Si data remain unexplained, and these regions indicate the preferred parameter space if these anomalies are due to dark matter.]]

There are currently no confirmed detections of dark matter from direct detection experiments, with the strongest exclusion limits coming from the [[Large Underground Xenon experiment|LUX]] and [[Cryogenic Dark Matter Search|SuperCDMS]] experiments, as shown in figure 2.
With 370 kilograms of xenon LUX is more sensitive than XENON or CDMS.<ref>
{{cite web |url=https://www.science.org/content/article/new-experiment-torpedoes-lightweight-dark-matter-particles |title=New Experiment Torpedoes Lightweight Dark Matter Particles |date=30 October 2013 |access-date=6 May 2014}}
</ref> First results from October 2013 report that no signals were seen, appearing to refute results obtained from less sensitive instruments.<ref>
{{cite web |url=http://newscenter.lbl.gov/news-releases/2013/10/30/lux-first-results/ |title=First Results from LUX, the World's Most Sensitive Dark Matter Detector |publisher=Berkeley Lab News Center |date=30 October 2013 |access-date=6 May 2014}}
</ref> and this was confirmed after the final data run ended in May 2016.<ref>[https://www.science.org/content/article/dark-matter-search-comes-empty Dark matter search comes up empty. July 2016]</ref>

Historically there have been four anomalous sets of data from different direct detection experiments, two of which have now been explained with backgrounds ([[CoGeNT]] and CRESST-II), and two which remain unexplained ([[DAMA/LIBRA]] and [[Cryogenic Dark Matter Search|CDMS-Si]]).<ref>{{cite journal |title=Largest-ever dark-matter experiment poised to test popular theory |url=http://www.nature.com/news/largest-ever-dark-matter-experiment-poised-to-test-popular-theory-1.18772 |journal=Nature |access-date=15 January 2017|doi=10.1038/nature.2015.18772 |year=2015 |last1=Cartlidge |first1=Edwin |s2cid=182831370 |url-access=subscription }}</ref><ref>{{cite journal |last1=Davis |first1=Jonathan H. |date=2015 |title=The Past and Future of Light Dark Matter Direct Detection |journal=International Journal of Modern Physics A |volume=30 |issue=15 |page=1530038 |arxiv=1506.03924 |bibcode=2015IJMPA..3030038D |doi=10.1142/S0217751X15300380 |s2cid=119269304}}</ref> In February 2010, researchers at CDMS announced that they had observed two events that may have been caused by WIMP-nucleus collisions.<ref name="strib">{{cite web |url=http://www.startribune.com/local/79624932.html?page=1&c=y |title=Key to the universe found on the Iron Range? |website=[[Star Tribune]] |access-date=December 18, 2009}}</ref><ref>
{{cite web
 |url    = http://cdms.berkeley.edu/0912.3592v1.pdf
 |title    = Results from the Final Exposure of the CDMS II Experiment
 |author    = CDMS Collaboration
 |access-date    = 2009-12-21
 |archive-date    = 2009-12-29
 |archive-url    = https://web.archive.org/web/20091229234000/http://cdms.berkeley.edu/0912.3592v1.pdf
 |url-status    = dead
}}. See also a non-technical summary:
{{cite web
 |url          = http://cdms.berkeley.edu/results_summary.pdf
 |title        = Latest Results in the Search for Dark Matter
 |author       = CDMS Collaboration
 |url-status   = dead
 |archive-url  = https://web.archive.org/web/20100618221140/http://cdms.berkeley.edu/results_summary.pdf
 |archive-date = 2010-06-18
}}</ref><ref>{{cite journal |author=The CDMS II Collaboration |date=2010 |title=Dark Matter Search Results from the CDMS II Experiment |journal=Science |volume=327 |issue=5973 |pages=1619–1621 |arxiv=0912.3592 |bibcode=2010Sci...327.1619C |doi=10.1126/science.1186112 |pmid=20150446 |s2cid=2517711}}</ref>

[[CoGeNT]], a smaller detector using a single germanium puck, designed to sense WIMPs with smaller masses, reported hundreds of detection events in 56 days.<ref name="NN-2010-02-26">{{cite journal |author=Hand |first=Eric |date=2010-02-26 |title=A CoGeNT result in the hunt for dark matter |url=http://www.nature.com/news/2010/100226/full/news.2010.97.html |journal=Nature |publisher=Nature News |doi=10.1038/news.2010.97|url-access=subscription }}</ref><ref>{{cite journal |title=Results from a Search for Light-Mass Dark Matter with a P-type Point Contact Germanium Detector |author=C. E. Aalseth |collaboration=CoGeNT collaboration |doi=10.1103/PhysRevLett.106.131301 |date=2011 |journal=Physical Review Letters |volume=106 |issue=13 |arxiv=1002.4703 |bibcode=2011PhRvL.106m1301A |pmid=21517370 |page=131301|s2cid=24822628 }}</ref> They observed an annual modulation in the event rate that could indicate light dark matter.<ref name="Dacey2011">{{cite web |last1=Dacey |first1=James |date=June 2011 |title=CoGeNT findings support dark-matter halo theory |url=http://physicsworld.com/cws/article/news/2011/jun/15/cogent-findings-support-dark-matter-halo-theory |access-date=5 May 2015 |publisher=physicsworld}}</ref> However a dark matter origin for the CoGeNT events has been refuted by more recent analyses, in favour of an explanation in terms of a background from surface events.<ref>{{cite journal |last1=Davis |first1=Jonathan H. |last2=McCabe |first2=Christopher |last3=Boehm |first3=Celine |title=Quantifying the evidence for Dark Matter in CoGeNT data |journal=Journal of Cosmology and Astroparticle Physics |date=2014 |volume=1408 |issue=8 |page=014 |doi=10.1088/1475-7516/2014/08/014 |arxiv = 1405.0495 |bibcode = 2014JCAP...08..014D |s2cid=54532870 }}</ref>

Annual modulation is one of the predicted signatures of a WIMP signal,<ref>{{cite journal|last1=Drukier|first1=Andrzej K.|last2=Freese|first2=Katherine|last3=Spergel|first3=David N.|title=Detecting cold dark-matter candidates|journal=Physical Review D|date=15 June 1986|volume=33|issue=12|pages=3495–3508|doi=10.1103/PhysRevD.33.3495|pmid=9956575|bibcode=1986PhRvD..33.3495D}}</ref><ref name="Freese1988">{{cite journal |author=Freese |first1=K. |last2=Frieman |first2=J. |last3=Gould |first3=A. |year=1988 |title=Signal Modulation in Cold Dark Matter Detection |journal=Physical Review D |volume=37 |issue=12 |pages=3388–3405 |bibcode=1988PhRvD..37.3388F |doi=10.1103/PhysRevD.37.3388 |osti=1448427 |pmid=9958634 |s2cid=2610174}}</ref> and on this basis the DAMA collaboration has claimed a positive detection. Other groups, however, have not confirmed this result. The CDMS data made public in May 2004 exclude the entire DAMA signal region given certain standard assumptions about the properties of the WIMPs and the dark matter halo, and this has been followed by many other experiments (see Figure 2).

The [[Korea Invisible Mass Search#COSINE|COSINE-100]] collaboration (a merging of KIMS and DM-Ice groups) published their results on replicating the DAMA/LIBRA signal in December 2018 in journal Nature; their conclusion was that "this result rules out WIMP–nucleon interactions as the cause of the annual modulation observed by the DAMA collaboration".<ref>{{cite journal | doi=10.1038/s41586-018-0739-1|pmid = 30518890| title=An experiment to search for dark-matter interactions using sodium iodide detectors| journal=Nature| volume=564| issue=7734| pages=83–86| year=2018| author1=COSINE-100 Collaboration| bibcode=2018Natur.564...83C|arxiv = 1906.01791|s2cid = 54459495}}</ref> In 2021 new results from COSINE-100 and [[ANAIS-112]] both failed to replicate the DAMA/LIBRA signal<ref>{{cite journal |last1=Amaré |first1=J. |last2=Cebrián |first2=S. |last3=Cintas |first3=D. |last4=Coarasa |first4=I. |last5=García |first5=E. |last6=Martínez |first6=M. |last7=Oliván |first7=M. A. |last8=Ortigoza |first8=Y. |last9=de Solórzano |first9=A. Ortiz |last10=Puimedón |first10=J. |last11=Salinas |first11=A. |date=2021-05-27 |title=Annual modulation results from three-year exposure of ANAIS-112 |url=https://link.aps.org/doi/10.1103/PhysRevD.103.102005 |journal=Physical Review D |language=en |volume=103 |issue=10 |pages=102005 |arxiv=2103.01175 |bibcode=2021PhRvD.103j2005A |doi=10.1103/PhysRevD.103.102005 |issn=2470-0010 |s2cid=232092298}}</ref><ref>{{cite journal |last1=Adhikari |first1=Govinda |last2=de Souza |first2=Estella B. |last3=Carlin |first3=Nelson |last4=Choi |first4=Jae Jin |last5=Choi |first5=Seonho |last6=Djamal |first6=Mitra |last7=Ezeribe |first7=Anthony C. |last8=França |first8=Luis E. |last9=Ha |first9=Chang Hyon |last10=Hahn |first10=In Sik |last11=Jeon |first11=Eunju |date=2021-11-12 |title=Strong constraints from COSINE-100 on the DAMA dark matter results using the same sodium iodide target |journal=Science Advances |language=en |volume=7 |issue=46 |pages=eabk2699 |bibcode=2021SciA....7.2699A |doi=10.1126/sciadv.abk2699 |issn=2375-2548 |pmc=8580298 |pmid=34757778|arxiv=2104.03537 }}</ref><ref>{{cite web |title=Is the end in sight for famous dark matter claim? |url=https://www.science.org/content/article/end-sight-famous-dark-matter-claim |access-date=2021-12-29 |website=www.science.org |language=en}}</ref> and in August 2022 COSINE-100 applied an analysis method similar to one used by DAMA/LIBRA and found a similar annual modulation suggesting the signal could be just a statistical artifact<ref>{{cite journal |last1=Adhikari |first1=G. |last2=Carlin |first2=N. |last3=Choi |first3=J. J. |last4=Choi |first4=S. |last5=Ezeribe |first5=A. C. |last6=Franca |first6=L. E. |last7=Ha |first7=C. |last8=Hahn |first8=I. S. |last9=Hollick |first9=S. J. |last10=Jeon |first10=E. J. |last11=Jo |first11=J. H. |last12=Joo |first12=H. W. |last13=Kang |first13=W. G. |last14=Kauer |first14=M. |last15=Kim |first15=B. H. |date=2023 |title=An induced annual modulation signature in COSINE-100 data by DAMA/LIBRA's analysis method |journal=Scientific Reports |volume=13 |issue=1 |page=4676 |doi=10.1038/s41598-023-31688-4 |pmid=36949218 |pmc=10033922 |arxiv=2208.05158 |bibcode=2023NatSR..13.4676A }}</ref><ref>{{cite journal |last=Castelvecchi |first=Davide |date=2022-08-16 |title=Notorious dark-matter signal could be due to analysis error |url=https://www.nature.com/articles/d41586-022-02222-9 |journal=Nature |language=en |doi=10.1038/d41586-022-02222-9|pmid=35974221 |s2cid=251624302 |url-access=subscription }}</ref> supporting a hypothesis first put forward in 2020.<ref>{{cite journal |author=Buttazzo |first=D. |display-authors=etal |year=2020 |title=Annual modulations from secular variations: relaxing DAMA? |journal=Journal of High Energy Physics |volume=2020 |issue=4 |page=137 |arxiv=2002.00459 |bibcode=2020JHEP...04..137B |doi=10.1007/JHEP04(2020)137 |s2cid=211010848}}</ref>