Ua hoʻomaʻemaʻe ʻo Fermi telescope i ka hoʻokuʻu ʻana i ka γ-ray i ke kikowaena o ko mākou home galaxy i ʻike ʻia ʻaʻole pōʻai a palahalaha. Kuhi ʻia ʻo Galactic Center Excess (GCE), ʻo kēia keu γ-ray he mea hiki ke hōʻailona o ka mea pōʻeleʻele e kū mai ana ma ke ʻano he hopena o ka hoʻopau ʻana iā ia iho o nā ʻāpana nui e launa pū ana me ka nāwaliwali (WIMPs), he moho mea pōʻeleʻele. Eia naʻe, ʻo ka nui o ka γ-ray i ʻike ʻia ma ke kikowaena galactic ma muli paha o ka millisecond pulsars kahiko (MSPs). I kēia manawa, ua manaʻo ʻia he spherical ka GCE morphology ma muli o ka mea ʻeleʻele (DM). Ua hōʻike ʻia kahi noiʻi hoʻohālikelike hou e hiki i ka morphology gamma-ray ma muli o DM ke ʻano nui ʻole a palahalaha. ʻO ia ke ʻano o ka hoʻopau ʻana i nā mea ʻeleʻele (DM) a me nā kuhiakau millisecond pulsars (MSPs) no ka GCE i ʻike ʻia. ʻO nā kukuna gamma i hana ʻia i ka luku ʻana i ka mea ʻeleʻele (DM) e loaʻa i kahi pae ikehu kiʻekiʻe loa ma kahi o 0.1 tera-electron-volts (TeV). ʻAʻole hiki i nā telescopes gamma-ray maʻamau ke ʻike pololei i kēia mau kiʻi kiʻi kiʻekiʻe. No laila, hiki ke hōʻoia i ke kumu hoʻohālike o ka Galactic Center Excess (GCE) i ka pau ʻana o nā haʻawina e ka tera γ-ray observatories like Cherenkov Telescope Array Observatory (CTAO) a me Southern Wide-field Gamma-ray Observatory (SWGO).
Ua hoʻomaka ka moʻolelo o ka mea pōʻeleʻele i ka makahiki 1933 i ka wā i ʻike ai ʻo Fritz Zwicky ʻaʻole hiki ke hoʻopaʻa a paʻa nā galaxies holo wikiwiki i ka Coma Cluster me ka ʻole o nā mea ʻē aʻe i ʻike ʻole ʻia akā hoʻohana ʻia ka hopena umekaumaha kūpono e hoʻōki i ka hāʻule ʻana o nā aniani. Ua haku ʻo ia i ka huaʻōlelo "mea pōʻeleʻele" e pili ana i kēlā mea ʻike ʻole. I ka makahiki 1960, ua hāʻawi mai ʻo Vera Rubin i ko mākou ʻike no ka mea ʻeleʻele. Ua ʻike ʻo ia ʻo nā hōkū ma nā ʻaoʻao o waho o Andromeda a me nā galaxia ʻē aʻe e kaʻapuni ana me ka wikiwiki e like me ka wikiwiki o nā hōkū i ke kikowaena. No ka hōʻuluʻulu o nā mea a pau i ʻike ʻia, pono e lele ka galaxy i mea e pono ai ke loaʻa kekahi mau mea ʻike ʻole ʻia e hoʻopaʻa pū i nā galaxies a hoʻohuli iā lākou i ka wikiwiki kiʻekiʻe. ʻO kāna mau ana ʻana o nā ʻōuli o ka Andromeda galaxy i hōʻike mua loa i ka mea ʻeleʻele.
I kēia manawa ʻike mākou ʻaʻole pili ka mea ʻeleʻele me ka māmā a i ʻole ka ikaika electromagnetic. ʻAʻole ia e hoʻomoʻa, e hoʻomālamalama a hoʻokuʻu paha i ke kukui a i ʻole nā radila electromagnetic ʻē aʻe a ʻike ʻole ʻia no laila ua kapa ʻia he pōʻeleʻele. Akā ʻo ia ka puʻupuʻu me ka umekaumaha a loaʻa ka hopena umekaumaha i nā mea maʻamau, a pēlā ke ʻano o kona hele ʻana ma ke ākea. Hoʻopaʻa pū ʻia nā galaxies i ke kaulike e ka hopena gravitational o ka mea pōʻeleʻele e like me 26.8% o ka nui o ka ikehu o ke ao holoʻokoʻa aʻo ke ao holoʻokoʻa e ʻike ʻia me nā mea maʻamau baryonic āpau i hana ʻia ai mākou a pau he 4.9% wale nō o ke ao holoʻokoʻa. ʻO ke koena 68.3% o ka ikehu nui o ke ao holoʻokoʻa he ikehu ʻeleʻele.
ʻAʻole ʻike ʻia ka mea ʻeleʻele maoli. ʻAʻohe mea nui i loko o ka ʻO ke kūlana kūlike loaʻa nā waiwai pono e lilo i mea ʻeleʻele. Malia paha, ʻo ka hypothetical "supersymmetric particles" he mau hoa pili i nā ʻāpana i loko o ke Kumu Maʻamau i mea pōʻeleʻele. Aia paha he ao like o ka mea pouli. ʻO nā WIMP (Weakly Interacting Massive Particles), axions, a i ʻole sterile neutrino, he mau ʻāpana i kuhi ʻia ma mua o ka Model Model e alakaʻi nei i nā moho. Eia naʻe, ʻaʻole i loaʻa ka holomua ma ka ʻike ʻana i ia mau mea.
Aia kekahi mau papahana (e like me ʻO ka hoʻokolohua XENON, Papahana DarkSide-20k, ʻO ka hoʻokolohua EURECA, a RES-NOVA) i kēia manawa no ka ʻike pololei ʻana i nā mea ʻeleʻele. ʻO kēia ka hapa nui o nā mea ʻike kinoea wai a i ʻole nā mea ʻike cryogenic i hoʻolālā ʻia e ʻike i nā hōʻailona nāwaliwali mai ka launa pū ʻana o nā mea ʻeleʻele. Eia nō naʻe, ʻoiai ka nui o nā ala hou, ʻaʻohe papahana i hiki ke ʻike pololei i nā mea ʻeleʻele.
No ka hōʻike pololei ʻole o ka mea ʻeleʻele, e ʻimi paha kekahi i nā hopena gravity o ka mea ʻeleʻele, e like me kā Fritz Zwicky lāua ʻo Vera Rubin i ʻike ai i ka mea ʻeleʻele ma ke aʻo ʻana i ke ʻano o ka paʻa ʻana o nā galaxies ʻoiai he kiʻekiʻe ka wikiwiki o ka mea maʻamau. Hiki i nā hopena gravity o ka lens (piʻo o ka mālamalama) a me nā hopena i ka neʻe ʻana o nā hōkū ma ka lewa hiki ke hāʻawi i nā hōʻike pololei ʻole o ka loaʻa ʻana o ka mea ʻeleʻele. Eia kekahi, hana ʻia nā huahana hoʻopau (e like me nā gamma-ray, neutrinos, a me nā kukuna cosmic) i ka wā e hui pū ai nā mea ʻeleʻele i kekahi i kekahi ma ke ākea. ʻO kekahi o ia wahi kahi i wānana ʻia ai ka mea ʻeleʻele e pili ana i nā huahana o ka luku ʻana i nā ʻāpana mea ʻeleʻele ke kikowaena o kā mākou home galaxy Milky Way.
Ka ʻike ʻana i nā mea ʻeleʻele i waenakonu o ko mākou home galaxy Milky Way
Aia nā hōʻailona o ka ʻālohilohi waena o ka microwave ma ke kikowaena o Milky Way (MW). Ua manaʻo ʻia ka ʻālohilohi ma muli o ka hoʻokuʻu ʻana o synchrotron mai nā electrons relativistic a me nā positron i hana ʻia i ka hoʻopau ʻia ʻana o ka mea pōʻeleʻele WIMP, no laila ua wānana ʻia kahi hōʻailona γ-ray hoʻonui i ka ikehu a hiki i kahi mau haneli GeV. Ma hope mai, ua ʻike ka Fermi-Large Area Telescope (LAT) i ka hōʻailona γ-ray i ʻike ʻia ʻo ka Galactic Center Excess (GCE). Ma hope koke iho, ua ʻike ʻia ʻo ka Galactic Center Excess (GCE) ma muli o nā hōkū neutron kahiko (millisecond pulsars). Ua manaʻo ʻia he mea koʻikoʻi ka morphology o ka GCE - ʻo ka GCE ʻano spherical symmetrical e hōʻike ana i ka hoʻokuʻu ʻana o ka γ-ray mai ka luku ʻana i nā mea pōʻeleʻele (DM) aʻo ka morphology palahalaha o GCE e hōʻike ana i ka hoʻokuʻu ʻana o γ-ray mai ka millisecond pulsars (MSP).
ʻO ka nānā nui ʻana o ka Milky Way galactic center e Fermi-Large Area Telescope (LAT) i hōʻike i kahi asphericity palahalaha. ʻO ka maʻamau, e hoʻopili kekahi i ka asphericity i ʻike ʻia i nā hōkū kahiko (MSP) akā naʻe, ua paʻi ʻia kahi noiʻi hou i paʻi ʻia ma ka 16 ʻOkakopa 2025 i ʻike ʻia nā morphologies GCE i wānana ʻia e nā hoku kahiko (MSP) a me nā hiʻohiʻona hoʻopau pōʻeleʻele (DM).
No ke aʻo ʻana i ka hāʻawi ʻana i ka mea ʻeleʻele, ua hana nā mea noiʻi i ka simulation o ka morphology o MW (Milky Way)-like galaxies. Ua ʻike lākou ʻaʻole spherical ka poʻe ʻeleʻele a puni nā galaxies a me nā ʻāpana waena o nā galaxia e like me ka manaʻo ʻia ma ke ʻano anisotropic. Akā, ua hōʻike ka hōʻike ʻana i kahi projection density mea ʻeleʻele palahalaha no nā galaxies āpau. Ua hōʻike pū ʻia kēia māhele ʻeleʻele non-axisymmetric (DM) e ka mōʻaukala hui o Milky Way galaxy i nā makahiki ʻekolu piliona mua o ka mōʻaukala o ke ao holoʻokoʻa. Hoʻopili ʻia ka morphology o GCE i ʻike ʻia ma luna o ka ʻāpana waena, i manaʻo ʻia ʻo ia ke ʻano o ka hāʻawi ʻana i ka hōkū kahiko (MSP). Ua hōʻike ʻia ka noiʻi hou e hana ana ka mea pōʻeleʻele (DM) i kahi hoʻohele pahu like. No laila, hiki ke hoʻopau ʻia nā mea ʻeleʻele (DM) a me nā kuhiakau millisecond pulsars (MSPs) no ka GCE i ʻike ʻia.
E ʻike ʻia paha ka GCE i ʻike ʻia ma muli o ka mea pōʻeleʻele (DM) a i ʻole ma muli o ka millisecond pulsars (MSPs) i ka wā e hoʻopau ai nā mea nānā γ-ray e like me Cherenkov Telescope Array Observatory (CTAO) a me Southern Wide-field Gamma-ray Observatory (SWGO) i kā lākou mau haʻawina tera-gamma ray i ka wā e hiki mai ana. ʻO nā kukuna gamma i hana ʻia ma ke ʻano he mea hoʻopau i ka mea ʻeleʻele (DM) ma ke kikowaena galactic he kiʻi kiʻi ikaika loa me ka pae ikehu kiʻekiʻe loa ma kahi o 0.1 tera-electron-volts (TeV). ʻAʻole hiki i nā telescopes gamma-ray maʻamau ke ʻike pololei i kēia mau kiʻi kiʻi ikaika. E lilo ana nā kukui Tera-gamma i pahuhopu nui no nā mea nānā γ-ray e hiki mai ana e like me CTAO a me SWGO.
ʻO kēia haʻawina he ʻanuʻu i mua i ka ʻike ʻana i ka mea ʻeleʻele ma ka lewa ma o kāna mau huahana luku akā naʻe e koi ʻia ka loaʻa ʻana o nā mea ʻeleʻele ma ke kikowaena galactic e hōʻoia ʻia e nā mea nānā kiʻekiʻe kiʻekiʻe γ-ray e like me CTAO a i ʻole SWGO i ka wā e hiki mai ana. ʻO ka holomua nui o ka ʻepekema o ka mea pōʻeleʻele, ʻo ia ka ʻike pololei ʻana i kekahi ʻāpana DM.
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E hoʻomaopopo ':
- Hochberg, Y., Kahn, YF, Leane, RK et al. Nā ala hou no ka ʻike ʻana i nā mea ʻeleʻele. Nat Rev Phys 4, 637–641 (2022). https://doi.org/10.1038/s42254-022-00509-4
- Misiaszeka M. a me Rossib N. 2024. ʻIke pololei i ka mea ʻeleʻele: he loiloi koʻikoʻi. Symmetry 2024, 16(2), 201; DOI: https://doi.org/10.3390/sym16020201
- Instituto de Física Corpuscular. I ka ʻimi ʻana i ka mea ʻeleʻele: kahi ala hou e ʻike ai i ka mea ʻike ʻole. 22 ʻAukake 2025. Loaʻa ma https://webific.ific.uv.es/web/en/content/search-dark-matter-new-approach-detecting-invisible
- Muru MM, et al 2025. Fermi-LAT Galactic Center Excess Morphology of Dark Matter in Simulations of the Milky Way Galaxy. Nā leka nānā kino. 135, 161005. Published 16 October 2025. DOI: https://doi.org/10.1103/g9qz-h8wd . Mana paʻi mua ma arXiv. Waiho ʻia 8 ʻAukake 2025. DOI: https://doi.org/10.48550/arXiv.2508.06314
- Ke Kulanui o Johns Hopkins. Nūhou - ʻO ka ʻālohilohi pohihihi i ke ala waiu hiki ke hōʻike i ka mea ʻeleʻele. Hoʻouna ʻia ma 16 ʻOkakopa 2025. Loaʻa ma https://hub.jhu.edu/2025/10/16/mysterious-glow-in-milky-way-dark-matter/
- Leibniz Institute for Astrophysics. Nūhou - Hōʻike ʻo Milky Way i ka nui o ka ray gamma ma muli o ka luku ʻana i nā mea ʻeleʻele. Hoʻopuka ʻia 17 ʻOkakopa 2025. Loaʻa ma https://www.aip.de/en/news/milkyway-gammaray-darkmatter-annihilation/
- Fermi Gamma-ray Space Telescope. Loaʻa ma https://science.nasa.gov/mission/fermi/
- Cherenkov Telescope Array Observatory (CTAO). Loaʻa ma https://www.ctao.org/emission-to-discovery/science/
- ʻO ka Southern Wide-field Gamma-ray Observatory (SWGO). Loaʻa ma https://www.swgo.org/SWGOWiki/doku.php?id=swgo_rel_pub
- ʻO ka Hale Nānā ʻo Tartu. ʻaoʻao ʻeleʻele o ke ao holoʻokoʻa. Loaʻa ma 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}