Na'urar hangen nesa ta Fermi ta yi tsaftataccen kallo na wuce haddi γ-ray a tsakiyar gidan galaxy ɗin mu wanda ya bayyana mara siffa kuma ba a kwance. Ana Nufinta da Wucewar Cibiyar Galactic (GCE), wannan wuce gona da iri na γ-ray mai yuwuwar sa hannu ne na kwayoyin duhu da ke tasowa azaman samfur na halakar da kai na manyan barbashi masu rauni (WIMPs), ɗan takarar ɓarna mai duhu. Duk da haka, yawan γ-ray da aka gani a cibiyar galactic na iya kasancewa saboda tsofaffin pulsars millisecond (MSPs). Har zuwa yanzu, an gudanar da cewa GCE ilimin halittar jiki saboda duhu kwayoyin halitta (DM) zai zama mai siffar zobe. Wani binciken kwaikwaiyo na baya-bayan nan ya nuna cewa ilimin halittar gamma-ray saboda DM zai iya zama maras kyau da daidaitawa. Wannan yana nufin duka abubuwan duhu (DM) annhilations da millisecond pulsars (MSPs) hasashe na GCE da aka lura suna yiwuwa daidai. Hasken gamma da aka samar a cikin halakar duhun kwayoyin halitta (DM) zai sami matsakaicin matakin makamashi na kusan 0.1 tera-electron-volts (TeV). Madaidaitan na'urorin hangen nesa na gamma-ray ba za su iya gano waɗannan photon masu ƙarfi kai tsaye ba. Don haka, tabbatar da samfurin duhu (DM) na Galactic Center Excess (GCE) zai yiwu bayan kammala karatun ta masu lura da tera γ-ray kamar Cherenkov Telescope Array Observatory (CTAO) da Kudancin Wide-field Gamma-ray Observatory (SWGO).
Labarin duhu ya fara ne a cikin 1933 lokacin da Fritz Zwicky ya lura cewa taurari masu saurin tafiya a cikin Coma Cluster ba za su iya tsayawa tare ba tare da kasancewar ƙarin al'amuran da ba a iya gani ko ta yaya amma suna yin tasiri mai ƙarfi don dakatar da taurari daga faɗuwa. Ya ƙirƙira kalmar “baƙin duhu” don nufin irin wannan al’amari marar ganuwa. A cikin 1960s, Vera Rubin ta ba da gudummawar seminal don fahimtar al'amuran duhu. Ta lura cewa taurarin da ke gefen Andromeda da sauran taurari suna jujjuyawa da sauri kamar gudun taurarin zuwa tsakiyar. Don jimlar duk abubuwan da aka lura, ya kamata galaxy ya tashi baya wanda ke buƙatar kasancewar wasu ƙarin abubuwa marasa ganuwa waɗanda ke haɗa taurarin tare da sa su jujjuya cikin sauri. Ma'aunin ta na jujjuyawa na Andromeda galaxy ya ba da shaidar farko na kwayoyin duhu.
Yanzu mun san cewa duhun kwayoyin halitta ba ya hulɗa da haske ko ƙarfin lantarki. Ba ya tsotsewa, yin tunani ko fitar da haske ko wani radiation na lantarki kuma ba a iya gani saboda haka ana kiransa duhu. Amma yana taruwa a hankali kuma yana da tasiri a kan al'amuran yau da kullun, kuma haka ake kwatanta kasancewarsa a sararin samaniya. Galaxies ana gudanar da su tare a cikin ma'auni ta hanyar tasirin yanayin duhu wanda ya kai kusan kashi 26.8% na yawan adadin kuzarin sararin samaniya yayin da dukkanin sararin samaniya da ake iya gani ciki har da duk wani abu na yau da kullun wanda mu duka mu ke da kashi 4.9% na sararin samaniya. Ragowar kashi 68.3% na yawan kuzarin da ke cikin sararin samaniya shine makamashi mai duhu.
Ba a san ainihin abin da duhun abu yake ba. Babu wani abu mai mahimmanci a cikin Tsarin Daidaitacce wanda ke da halayen da ake buƙata don zama duhun abu. Wataƙila, "ƙwayoyin da suka fi ƙarfin hali" waɗanda suke haɗin gwiwa da ƙwayoyin da ke cikin Tsarin Daidaitacce suna yin duhun abu. Wataƙila akwai duniyar duhu mai kama da juna. WIMPs (Weakly Interacting Massive Barticles), axions, ko neutrinos marasa tsabta sune ƙwayoyin da aka yi hasashen sun wuce Tsarin Daidaitacce waɗanda sune manyan 'yan takara. Duk da haka, babu wata nasara da aka samu tukuna a gano irin waɗannan ƙwayoyin.
Akwai ayyuka da dama (kamar XENON Experiment, DarkSide-20k Project , EURECA Rxperiment, da RES-NOVA ) da ake gudanarwa a halin yanzu don gano ƙwayoyin duhu kai tsaye. Waɗannan galibi na'urorin gano iskar gas ne masu daraja ko na'urorin gano abubuwa masu ban tsoro waɗanda aka tsara don gano alamun da ba su da ƙarfi daga hulɗar ƙwayoyin duhu. Duk da haka, duk da sabbin hanyoyin da aka saba bi, babu wani aiki da ya sami damar gano ƙwayoyin duhu kai tsaye.
Don hujjojin kai tsaye na al'amarin duhu, mutum na iya neman tasirin abubuwan duhu, kamar yadda Fritz Zwicky da Vera Rubin suka yi don gano duhu ta hanyar nazarin yadda ake haɗa taurarin tare duk da cewa suna da saurin da bai dace ba ga al'amuran yau da kullun. Sakamakon gravitational lensing (lankwashe haske) da tasirin motsin taurari a sararin samaniya na iya ba da shaida kai tsaye na kasancewar kwayoyin duhu. Bugu da kari, kayayyakin halaka (kamar gamma-rays, neutrinos, da cosmic rays) da aka yi a lokacin da barbashi masu duhu suka yi karo da juna a sararin samaniya kuma na iya nuna kasancewar kwayoyin duhu. Ɗaya daga cikin irin wannan wurin da aka yi hasashen duhun kwayoyin halitta bisa ga abubuwan da ke halakar da barbashi masu duhu shine tsakiyar gidanmu na galaxy Milky Way.
Gano abubuwan duhu a tsakiyar gidanmu na galaxy Milky Way
Akwai alamun wuce gona da iri na microwave tsakiyar haske a tsakiyar Milky Way (MW). An ba da shawarar wuce gona da iri ya zama saboda fitar da synchrotron daga electrons masu alaƙa da positron da aka samar a cikin halakar duhun al'amuran WIMP, don haka tsawaita siginar γ-ray a cikin kewayon makamashi har zuwa 'yan ɗari GeV an annabta. Daga baya, na'urar hangen nesa ta Fermi-Large Area (LAT) ta gano siginar γ-ray wanda aka gano a matsayin Galactic Center Excess (GCE). Ba da da ewa, an gane cewa Galactic Center Excess (GCE) na iya kasancewa saboda tsoffin taurarin neutron (pulsars millisecond). An yi tunanin cewa ilimin halittar jiki na GCE zai kasance da mahimmanci - GCE mai siffa mai siffa mai siffa zai zama nuni ga fitar da γ-ray daga halakar kwayoyin halitta (DM) yayin da ɓangarorin ilimin halittar jiki na GCE zai kasance yana nuni da fitar da γ-ray daga millisecond pulsars (MSP).
Dubawa mai zurfi na cibiyar galactic Milky Way ta Fermi-Large Area Telescope (LAT) ya nuna baƙar fata. Yawanci, mutum zai danganta abin da aka lura ga tsoffin taurari (MSP) duk da haka wani bincike na baya-bayan nan da aka buga a ranar 16 ga Oktoba 2025 ya kammala da cewa yanayin halittar GCE da aka annabta ta tsoffin taurari (MSP) da duhun al'amura (DM) ƙirar halaka ba su da bambanci.
Don nazarin rarraba abubuwan duhu, masu binciken sun gudanar da simulation na morphology na MW (Milky Way) -kamar galaxies. Sun gano cewa duhun al'amarin da ke kewaye da taurari da kuma kewayen yankuna na tsakiya na taurari ba su da yawa kamar yadda aka zaci a cikin samfurin anisotropic. Madadin haka, binciken ya nuna tsinkayar tsinkayar adadin kwayoyin duhu ga duk taurarin. An kuma nuna wannan rarrabawar duhun da ba axisymmetric (DM) ta tarihin haɗewar tarihin galaxy Milky Way a cikin shekaru biliyan uku na farkon tarihin sararin samaniya. Halin yanayin halittar GCE da aka lura an daidaita shi akan yankin tsakiya, wanda gabaɗaya ana tunanin sifa ce ta rarraba tsohuwar tauraro (MSP). Sabon binciken ya nuna cewa duhu (DM) yana haifar da irin wannan rarraba akwatin. Don haka, duka biyun duhun kwayoyin halitta (DM) annhilations da millisecond pulsars (MSPs) na hasashen GCE da aka lura suna yiwuwa daidai.
Ko GCE da aka lura yana da duhu (DM) ko kuma saboda millisecond pulsars (MSPs) za a san lokacin da γ-ray observatories kamar Cherenkov Telescope Array Observatory (CTAO) da Southern Wide-field Gamma-ray Observatory (SWGO) kammala karatun tera-gamma ray a nan gaba. Hasken gamma da aka samar azaman samfurin ɓarkewar kwayoyin halitta (DM) a cikin cibiyar galactic zai zama ultra-high-power photons tare da matsanancin ƙarfin kuzarin kusan 0.1 tera-electron-volts (TeV). Madaidaitan na'urorin hangen nesa na gamma-ray ba za su iya gano waɗannan photon masu ƙarfi kai tsaye ba. Tera-gamma haskoki za su zama muhimmiyar manufa ga masu lura da γ-ray na gaba kamar CTAO da SWGO.
Wannan binciken wani mataki ne na ci gaba a cikin gano kwayoyin duhu a sararin samaniya ta hanyar abubuwan da ke lalata su duk da haka kasancewar kwayoyin duhu a cibiyar galactic zai buƙaci tabbatarwa ta hanyar ultra-high energy γ-ray observatories kamar CTAO ko SWGO a nan gaba. Babban ci gaba mai mahimmanci a cikin kimiyyar kwayoyin duhu zai zama gano kowane ƙwayar DM kai tsaye.
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References:
- Hochberg, Y., Kahn, YF, Leane, RK et al. Sabbin hanyoyin gano abubuwa masu duhu. Nat Rev Phys 4, 637-641 (2022). https://doi.org/10.1038/s42254-022-00509-4
- Misiaszeka M. da Rossib N. 2024. Gano kai tsaye na kwayoyin duhu: nazari mai mahimmanci. Alamar alama 2024, 16 (2), 201; DOI: https://doi.org/10.3390/sym16020201
- Instituto de Física Corpuscular. A cikin binciken kwayoyin duhu: sabuwar hanya don gano ganuwa. 22 Agusta 2025. Akwai a https://webific.ific.uv.es/web/en/content/search-dark-matter-new-approach-detecting-invisible
- Muru MM, et al 2025. Cibiyar Fermi-LAT Galactic Excess Morphology na Dark Matter a cikin kwaikwaiyo na Milky Way Galaxy. Wasiƙun Nazarin Jiki. 135, 161005. An buga 16 Oktoba 2025. DOI: https://doi.org/10.1103/g9qz-h8wd . Sigar bugu a arXiv. An ƙaddamar da Agusta 8, 2025. DOI: https://doi.org/10.48550/arXiv.2508.06314
- Jami'ar Johns Hopkins. Labarai - Haske mai ban mamaki a hanyar madara na iya zama shaida na kwayoyin duhu. An buga a kan 16 Oktoba 2025. Akwai a https://hub.jhu.edu/2025/10/16/mysterious-glow-in-milky-way-dark-matter/
- Cibiyar Leibniz don Astrophysics. Labarai - Milky Way yana nuna wuce gona da iri na gamma ray saboda halakar duhu. An buga 17 Oktoba 2025. Akwai a https://www.aip.de/en/news/milkyway-gammaray-darkmatter-annihilation/
- Fermi Gamma-ray Space Telescope. Akwai a https://science.nasa.gov/mission/fermi/
- Cherenkov Telescope Array Observatory (CTAO). Akwai a https://www.ctao.org/emission-to-discovery/science/
- The Southern Wide-field Gamma-ray Observatory (SWGO). Akwai a https://www.swgo.org/SWGOWiki/doku.php?id=swgo_rel_pub
- Tartu Observatory. Gefen Duhun Duniya. Akwai a https://kosmos.ut.ee/en/dark-side-of-the-universe
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, this excess γ-ray is a possible signature of dark matter arising as a product of self-annihilations of weakly interacting massive particles (WIMPs), a dark matter particle candidate. However, the excess γ-ray observed at the galactic centre may also be due to old millisecond pulsars (MSPs). Hitherto, it was held that the morphology GCE due to dark matter (DM) would be spherical. A recent simulation study reveals that gamma-ray morphology due to DM could be significantly nonspherical and flattened. This means both dark matter (DM) annihilations and millisecond pulsars (MSPs) hypotheses for the observed GCE are equally possible. The gamma rays produced in the annihilation of dark matter (DM) would have an extremely high energy level of approximately 0.1 tera-electron-volts (TeV). The standard gamma-ray telescopes cannot detect these high-energy photons directly. Hence, confirmation of dark matter (DM) model of Galactic Centre Excess (GCE) would be possible upon completion of studies by the tera γ-ray observatories like CTAO and SWGO.){kind=link}