DAMA/LIBRA

Last updated

The DAMA/LIBRA experiment [1] is a particle detector experiment designed to detect dark matter using the direct detection approach, by using a matrix of NaI(Tl) scintillation detectors to detect dark matter particles in the galactic halo. The experiment aims to find an annual modulation of the number of detection events, caused by the variation of the velocity of the detector relative to the dark matter halo as the Earth orbits the Sun. It is located underground at the Laboratori Nazionali del Gran Sasso in Italy.

Contents

It is a follow-on to the DAMA/NaI experiment which observed an annual modulation signature over 7 annual cycles (1995-2002). The experiment was first proposed by Dr. Pierluigi Belli,[ citation needed ] who is now the research director of the Italian National Institute of Nuclear Physics.[ citation needed ]

While DAMA/LIBRA has published exciting results, the validity of those results has been widely disputed; they have not made their data or practices publicly available, and their methods of background noise reduction is such that it may actually account for a large part of their proposed signal annual modulation. [2] Two other studies, attempting to replicate the DAMA/LIBRA experiment (adhering to current publication and data availability practices) using the same method - COSINE-100 and ANAIS-112 - have shown no evidence of annual modulation. [3] [4] [5]

In 2020, a possible explanation of the reported modulation was pointed out as originating from the data analysis procedure. A yearly subtraction of the constant component can give rise to a sawtooth residual in the presence of a slower time dependence. [6]

Detector

The detector is made of 25 highly radiopure scintillating thallium-doped sodium iodide (NaI(Tl)) crystals placed in a 5 by 5 matrix. Each crystal is coupled to two low background photomultipliers. The detectors are placed inside a sealed copper box flushed with highly pure nitrogen; to reduce the natural environmental background the copper box is surrounded by a low background multi-ton shield. In addition, 1 m of concrete, made from the Gran Sasso rock material, almost fully surrounds this passive shield. The installation has a 3-level sealing system which prevents environmental air reaching the detectors. The whole installation is air-conditioned and several operative parameters are continuously monitored and recorded.

DAMA/LIBRA was upgraded in 2008 and in 2010. [7] In particular, after the upgrade in 2010 the experiment entered in its phase 2, with an increase of the set-up’s sensitivity thanks to the lowering of the energy threshold. The DAMA/LIBRA-phase 2 is in data taking as of 2022.

Operation and results

DAMA/LIBRA phase 1 data collection started in September 2003. The DAMA/LIBRA released data correspond to 7 annual cycles. [8] Considering these data together with those by DAMA/NaI, a total exposure (1.33 ton × yr) has been collected over 14 annual cycles. This experiment has further confirmed the presence of a model-independent annual modulation effect in the data in 2-6 keV range that satisfy all the features expected for a dark matter signal with high statistical significance.

As previously done for DAMA/NaI, careful investigations on absence of any significant systematics or side reaction in DAMA/LIBRA have been quantitatively carried out. [8] [9]

The obtained model independent evidence is compatible with a wide set of scenarios regarding the nature of the dark matter candidate and related astrophysical and particle physics. [10] [11]

As of 2021, the DAMA/LIBRA experiment is continuing. [12]

Failure to replicate

The results can be compared with the CoGeNT signal [13] [14] [15] [16] and other experiment limits to evaluate interpretations as WIMPs, [17] neutralino, [18] and other models. However the CoGeNT-signal has since been shown to have resulted from unaccounted background from surface effects; after accounting for this background, the CoGeNT-signal has been shown to be compatible with null results (that is, no signal at all).

The COSINE-100 collaboration has been working in Korea towards confirming or refuting the DAMA-signal. They are using similar experimental setup to DAMA (NaI(Tl)-crystals). They published their results in December 2018 in the journal Nature; their result rules out spin-independent WIMP–nucleon interactions as the cause of the annual modulation observed by the DAMA collaboration. [19]

In May 2021, the ANAIS particle detector failed to replicate the results of the DAMA experiments after 3 years of data collection [20] and in November new results from COSINE-100 experiment after 1.7 years of data collection also failed to replicate the signal of DAMA. [21] [22]

A possible explanation of the reported modulation was pointed out as originating from the data analysis procedure. A yearly subtraction of the constant component can give rise to a sawtooth residual in the presence of a slower time dependence, [6] however later analysis shows that the data from DAMA/LIBRA is best explained by a cosine modulation over a sawtooth. [23] New information about this hypothesis came in August 2022 when COSINE-100 applied an analysis method similar to one used by DAMA/LIBRA and found a similar annual modulation, however with "a modulation phases that is almost opposite to that observed by DAMA/LIBRA". [24]

SABRE

The obvious criticism of the seasonal variation of events recorded in the DAMA/LIBRA experiment is that it is in fact due to some purely seasonal effect unconnected with WIMPs. Although the deep underground location minimizes temperature swings and other direct sunlight effects, there are annual humidity fluctuations and other non-obvious effects. At the moment, all these criticisms are taken into account by DAMA collaboration in analysis of the experimental data and they have been excluded, as discussed in published results. A repetition of this experiment in the Southern Hemisphere with the variation in phase with DAMA/LIBRA would discount this objection; if on the other hand variation was detected in the Southern Hemisphere that was 6 months out of phase with DAMA/LIBRA, then the seasonal variation objection would be upheld.

Improved versions of DAMA/LIBRA, named SABRE (Sodium-iodide with Active Background REjection) were planned for construction in two places. One at LNGS, and the other in Australia at the Stawell Underground Physics Laboratory (SUPL), [25] a laboratory being constructed 1025 m below the surface in a gold mine in Stawell, Victoria. First results were expected in 2017. [26] The construction of the Stawell Underground Physics Laboratory (SUPL) was halted by the shutdown of its host mine in 2016. Construction restarted around one year later and as of October 2019 was proceeding.

The host laboratory, SUPL, was opened in August 2022. The SABRE experiment is planned to be brought underground to SUPL during the last months of 2022 and data collection is planned to start in 2023. [27]

Related Research Articles

<span class="mw-page-title-main">Dark matter</span> Concept in cosmology

In astronomy, dark matter is a hypothetical form of matter that does not interact with light or other electromagnetic radiation. Dark matter is implied by gravitational effects which cannot be explained by general relativity unless more matter is present than can be observed. Such effects occur in the context of formation and evolution of galaxies, gravitational lensing, the observable universe's current structure, mass position in galactic collisions, the motion of galaxies within galaxy clusters, and cosmic microwave background anisotropies.

Weakly interacting massive particles (WIMPs) are hypothetical particles that are one of the proposed candidates for dark matter.

In physics, mirror matter, also called shadow matter or Alice matter, is a hypothetical counterpart to ordinary matter.

The DAMA/NaI experiment investigated the presence of dark matter particles in the galactic halo by exploiting the model-independent annual modulation signature. Based on the Earth's orbit around the Sun and the solar system's speed with respect to the center of the galaxy, the Earth should be exposed to a higher flux of dark matter particles around June 1, when its orbital speed is added to the one of the solar system with respect to the galaxy and to a smaller one around December 2, when the two velocities are subtracted. The annual modulation signature is distinctive since the effect induced by dark matter particles must simultaneously satisfy many requirements.

The Cryogenic Dark Matter Search (CDMS) is a series of experiments designed to directly detect particle dark matter in the form of Weakly Interacting Massive Particles. Using an array of semiconductor detectors at millikelvin temperatures, CDMS has at times set the most sensitive limits on the interactions of WIMP dark matter with terrestrial materials. The first experiment, CDMS I, was run in a tunnel under the Stanford University campus. It was followed by CDMS II experiment in the Soudan Mine. The most recent experiment, SuperCDMS, was located deep underground in the Soudan Mine in northern Minnesota and collected data from 2011 through 2015. The series of experiments continues with SuperCDMS SNOLAB, an experiment located at the SNOLAB facility near Sudbury, Ontario, in Canada that started construction in 2018 and is expected to start data taking in early 2020s.

<span class="mw-page-title-main">MINOS</span> Particle physics experiment

Main injector neutrino oscillation search (MINOS) was a particle physics experiment designed to study the phenomena of neutrino oscillations, first discovered by a Super-Kamiokande (Super-K) experiment in 1998. Neutrinos produced by the NuMI beamline at Fermilab near Chicago are observed at two detectors, one very close to where the beam is produced, and another much larger detector 735 km away in northern Minnesota.

The XENON dark matter research project, operated at the Italian Gran Sasso National Laboratory, is a deep underground detector facility featuring increasingly ambitious experiments aiming to detect hypothetical dark matter particles. The experiments aim to detect particles in the form of weakly interacting massive particles (WIMPs) by looking for rare nuclear recoil interactions in a liquid xenon target chamber. The current detector consists of a dual phase time projection chamber (TPC).

In astrophysics and particle physics, self-interacting dark matter (SIDM) is an alternative class of dark matter particles which have strong interactions, in contrast to the standard cold dark matter model (CDM). SIDM was postulated in 2000 as a solution to the core-cusp problem. In the simplest models of DM self-interactions, a Yukawa-type potential and a force carrier φ mediates between two dark matter particles. On galactic scales, DM self-interaction leads to energy and momentum exchange between DM particles. Over cosmological time scales this results in isothermal cores in the central region of dark matter haloes.

<span class="mw-page-title-main">DEAP</span> Dark matter search experiment

DEAP is a direct dark matter search experiment which uses liquid argon as a target material. DEAP utilizes background discrimination based on the characteristic scintillation pulse-shape of argon. A first-generation detector (DEAP-1) with a 7 kg target mass was operated at Queen's University to test the performance of pulse-shape discrimination at low recoil energies in liquid argon. DEAP-1 was then moved to SNOLAB, 2 km below Earth's surface, in October 2007 and collected data into 2011.

PVLAS aims to carry out a test of quantum electrodynamics and possibly detect dark matter at the Department of Physics and National Institute of Nuclear Physics in Ferrara, Italy. It searches for vacuum polarization causing nonlinear optical behavior in magnetic fields. Experiments began in 2001 at the INFN Laboratory in Legnaro and continue today with new equipment.

<span class="mw-page-title-main">Light dark matter</span> Dark matter weakly interacting massive particles candidates with masses less than 1 GeV

Light dark matter, in astronomy and cosmology, are dark matter weakly interacting massive particles (WIMPS) candidates with masses less than 1 GeV. These particles are heavier than warm dark matter and hot dark matter, but are lighter than the traditional forms of cold dark matter, such as Massive Compact Halo Objects (MACHOs). The Lee-Weinberg bound limits the mass of the favored dark matter candidate, WIMPs, that interact via the weak interaction to GeV. This bound arises as follows. The lower the mass of WIMPs is, the lower the annihilation cross section, which is of the order , where m is the WIMP mass and M the mass of the Z-boson. This means that low mass WIMPs, which would be abundantly produced in the early universe, freeze out much earlier and thus at a higher temperature, than higher mass WIMPs. This leads to a higher relic WIMP density. If the mass is lower than GeV the WIMP relic density would overclose the universe.

<span class="mw-page-title-main">EDELWEISS</span>

EDELWEISS is a dark matter search experiment located at the Modane Underground Laboratory in France. The experiment uses cryogenic detectors, measuring both the phonon and ionization signals produced by particle interactions in germanium crystals. This technique allows nuclear recoils events to be distinguished from electron recoil events.

<span class="mw-page-title-main">Modern searches for Lorentz violation</span> Tests of special relativity

Modern searches for Lorentz violation are scientific studies that look for deviations from Lorentz invariance or symmetry, a set of fundamental frameworks that underpin modern science and fundamental physics in particular. These studies try to determine whether violations or exceptions might exist for well-known physical laws such as special relativity and CPT symmetry, as predicted by some variations of quantum gravity, string theory, and some alternatives to general relativity.

The Korea Invisible Mass Search (KIMS), is a South Korean experiment, led by Sun Kee Kim, searching for weakly interacting massive particles (WIMPs), one of the candidates for dark matter. The experiments use CsI(Tl) crystals at Yangyang Underground Laboratory (Y2L), in tunnels from a preexisting underground power plant. KIMS is supported by the Creative Research Initiative program of the Korea Science and Engineering Foundation. It is the first physics experiment located, and largely built, in Korea.

The Particle and Astrophysical Xenon Detector, or PandaX, is a dark matter detection experiment at China Jinping Underground Laboratory (CJPL) in Sichuan, China. The experiment occupies the deepest underground laboratory in the world, and is among the largest of its kind.

The Stawell Underground Physics Laboratory (SUPL) is a laboratory 1 km deep in the Stawell Gold Mine, located in Stawell, Shire of Northern Grampians, Victoria, Australia. Together with the planned Agua Negra Deep Experiment Site (ANDES) at the Agua Negra Pass, it is one of just two underground particle physics laboratories in the Southern Hemisphere and shall conduct research into dark matter.

The CoGeNT experiment has searched for dark matter. It uses a single germanium crystal as a cryogenic detector for WIMP particles. CoGeNT has operated in the Soudan Underground Laboratory since 2009.

<span class="mw-page-title-main">ANAIS-112</span> Spanish dark matter direct detection experiment

ANAIS is a dark matter direct detection experiment located at the Canfranc Underground Laboratory (LSC), in Spain, operated by a team of researchers of the CAPA at the University of Zaragoza.

Direct detection of dark matter is the science of attempting to directly measure dark matter collisions in Earth-based experiments. Modern astrophysical measurements, such as from the Cosmic Microwave Background, strongly indicate that 85% of the matter content of the universe is unaccounted for. Although the existence of dark matter is widely believed, what form it takes or its precise properties has never been determined. There are three main avenues of research to detect dark matter: attempts to make dark matter in accelerators, indirect detection of dark matter annihilation, and direct detection of dark matter in terrestrial labs. The founding principle of direct dark matter detection is that since dark matter is known to exist in the local universe, as the Earth, Solar System, and the Milky Way Galaxy carve out a path through the universe they must intercept dark matter, regardless of what form it takes.

Daniel S. Akerib is an American particle physicist and astrophysicist. He was elected in 2008 a fellow of the American Physical Society (APS).

References

  1. ↑ R. Bernabei; et al. (2008). "The DAMA/LIBRA apparatus". Nuclear Instruments and Methods in Physics Research A . 592 (3): 297–315. arXiv: 0804.2738 . Bibcode:2008NIMPA.592..297B. doi:10.1016/j.nima.2008.04.082. S2CID   15785910.
  2. ↑ A controversial sighting of dark matter is looking even shakier 2018
  3. ↑ Mystery of dark-matter signal deepens with replication attempts March 2019
  4. ↑ Annual modulation results from three-year exposure of ANAIS-112 Amare 2021
  5. ↑ An experiment to search for dark-matter interactions using sodium iodide detectors COSINE-100 2018
  6. 1 2 D. Buttazzo; et al. (2020). "Annual modulations from secular variations: relaxing DAMA?". Journal of High Energy Physics. 2020 (4): 137. arXiv: 2002.00459 . Bibcode:2020JHEP...04..137B. doi:10.1007/JHEP04(2020)137. S2CID   211010848.
  7. ↑ R. Bernabei; et al. (2012). "Performances of the new high quantum efficiency PMTs in DAMA/LIBRA". Journal of Instrumentation. 7 (3): 03009. arXiv: 1002.1028 . Bibcode:2012JInst...7.3009B. doi:10.1088/1748-0221/7/03/P03009. S2CID   250677616.
  8. 1 2 R. Bernabei; et al. (2013). "Final model independent result of DAMA/LIBRA–phase1". European Physical Journal C . 73 (12): 2648. arXiv: 1308.5109 . Bibcode:2013EPJC...73.2648B. doi:10.1140/epjc/s10052-013-2648-7. S2CID   118668829.
  9. ↑ R. Bernabei; et al. (2012). "No role for muons in the DAMA annual modulation results". European Physical Journal C . 72 (7): 2064. arXiv: 1202.4179 . Bibcode:2012EPJC...72.2064B. doi:10.1140/epjc/s10052-012-2064-4. S2CID   54078935.
  10. ↑ A. Bottino; et al. (2012). "Phenomenology of light neutralinos in view of recent results at the CERN Large Hadron Collider". Physical Review D . 85 (9): 095013. arXiv: 1112.5666 . Bibcode:2012PhRvD..85i5013B. doi:10.1103/PhysRevD.85.095013. S2CID   53551559.
  11. ↑ M. R. Buckley; et al. (2011). "Particle Physics Implications for CoGeNT, DAMA, and Fermi". Physics Letters B . 702 (4): 216–219. arXiv: 1011.1499 . Bibcode:2011PhLB..702..216B. doi:10.1016/j.physletb.2011.06.090. S2CID   118389780.
  12. ↑ Bernabei, R.; Belli, P.; Bussolotti, A.; Caracciolo, V.; Cappella, F.; Cerulli, R.; Dai, C.J.; d'Angelo, A.; Ferrari, N.; Incicchitti, A.; Leoncini, A.; Ma, X.H.; Mattei, A.; Merlo, V.; Montecchia, F.; Sheng, X.D.; Ye, Z.P. (2021). "Further results from DAMA/LIBRA-phase2 and perspectives". Nuclear Physics and Atomic Energy. 22 (4): 329–342. Bibcode:2021NPAE...22..329B. doi: 10.15407/jnpae2021.04.329 . hdl: 2108/301167 . S2CID   249534111.
  13. ↑ C.E. Aalseth; et al. (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. PMID   21517370. S2CID   24822628.
  14. ↑ C.E. Aalseth; et al. (2011). "Search for an Annual Modulation in a P-type Point Contact Germanium Dark Matter Detector". Physical Review Letters . 107 (14): 141301. arXiv: 1106.0650 . Bibcode:2011PhRvL.107n1301A. doi:10.1103/PhysRevLett.107.141301. PMID   22107183. S2CID   7696495.
  15. ↑ M.T. Frandsen; et al. (2011). "On the DAMA and CoGeNT Modulations". Physical Review D . 84 (4): 041301. arXiv: 1105.3734 . Bibcode:2011PhRvD..84d1301F. doi:10.1103/PhysRevD.84.041301. S2CID   118416204.
  16. ↑ Dan Hooper, Chris Kelso (2011). "Implications of CoGeNT's New Results For Dark Matter". Physical Review D . 84 (8): 083001. arXiv: 1106.1066 . Bibcode:2011PhRvD..84h3001H. doi:10.1103/PhysRevD.84.083001. S2CID   119266643.
  17. ↑ A. Liam Fitzpatrick; et al. (2010). "Implications of CoGeNT and DAMA for Light WIMP Dark Matter". Physical Review D . 81 (11): 115005. arXiv: 1003.0014 . Bibcode:2010PhRvD..81k5005F. doi:10.1103/PhysRevD.81.115005. S2CID   56025384.
  18. ↑ A.V. Belikov; et al. (2011). "CoGeNT, DAMA, and Light Neutralino Dark Matter". Physics Letters B . 705 (1–2): 82–86. arXiv: 1009.0549 . Bibcode:2011PhLB..705...82B. doi:10.1016/j.physletb.2011.09.081. S2CID   119243520.
  19. ↑ The COSINE-100 Collaboration (2018). "An experiment to search for dark-matter interactions using sodium iodide detectors". Nature. 564 (7734): 83–86. arXiv: 1906.01791 . Bibcode:2018Natur.564...83C. doi:10.1038/s41586-018-0739-1. PMID   30518890. S2CID   54459495.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  20. ↑ J. Amaré; et al. (2021). "Annual modulation results from three-year exposure of ANAIS-112". Physical Review D. 103 (10): 102005. arXiv: 2103.01175 . Bibcode:2021PhRvD.103j2005A. doi:10.1103/PhysRevD.103.102005. S2CID   232092298.
  21. ↑ Adhikari, Govinda; de Souza, Estella B.; Carlin, Nelson; Choi, Jae Jin; Choi, Seonho; Djamal, Mitra; Ezeribe, Anthony C.; França, Luis E.; Ha, Chang Hyon; Hahn, In Sik; Jeon, Eunju (2021-11-12). "Strong constraints from COSINE-100 on the DAMA dark matter results using the same sodium iodide target". Science Advances. 7 (46): eabk2699. arXiv: 2104.03537 . Bibcode:2021SciA....7.2699A. doi:10.1126/sciadv.abk2699. ISSN   2375-2548. PMC   8580298 . PMID   34757778.
  22. ↑ "Is the end in sight for famous dark matter claim?". www.science.org. Retrieved 2021-12-29.
  23. ↑ Messina, Andrea; Nardecchia, Marco; Piacentini, Stefano (2020-04-22). "Annual modulations from secular variations: not relaxing DAMA?". Journal of Cosmology and Astroparticle Physics. 2020 (4): 037. arXiv: 2003.03340 . Bibcode:2020JCAP...04..037M. doi:10.1088/1475-7516/2020/04/037. ISSN   1475-7516.
  24. ↑ Adhikari, G.; Carlin, N.; Choi, J. J.; Choi, S.; Ezeribe, A. C.; Franca, L. E.; Ha, C.; Hahn, I. S.; Hollick, S. J.; Jeon, E. J.; Jo, J. H.; Joo, H. W.; Kang, W. G.; Kauer, M.; Kim, B. H. (2023). "An induced annual modulation signature in COSINE-100 data by DAMA/LIBRA's analysis method". Scientific Reports. 13 (1): 4676. arXiv: 2208.05158 . Bibcode:2023NatSR..13.4676A. doi:10.1038/s41598-023-31688-4. PMC   10033922 . PMID   36949218.
  25. ↑ Roberts, Glenn Jr. (23 October 2014). "Australia's first dark matter experiment". Symmetry Magazine.
  26. ↑ "Dark Matter: A Southern Hemisphere Perspective". 26 November 2015.
  27. ↑ https://www.supl.org.au/ [ bare URL ]
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.