An gano raƙuman nauyi kai tsaye a karon farko a shekarar 2015 bayan ƙarni ɗaya na hasashensa ta hanyar Ka'idar Dangantaka ta Einstein a shekarar 1916. Amma, ba a gano asalin raƙuman nauyi mai ci gaba da ƙarancin mita ba a duk faɗin duniya . Masu bincike a Arewacin Amurka Nanohertz Observatory for Gravitational Waves (NANOGrav) kwanan nan sun ba da rahoton gano wata siginar ƙarancin mita wadda za ta iya zama 'Bayanin raƙuman nauyi mai nauyi (GWB)'.
Ka'idar dangantaka ta gaba ɗaya da Einstein ya gabatar a shekarar 1916 ta annabta cewa manyan abubuwan da suka faru a sararin samaniya kamar supernova ko haɗakar ramukan baƙi ya kamata su haifar da raƙuman nauyi waɗanda ke yaɗuwa a cikin Duniya . Ya kamata duniya ta cika da raƙuman nauyi daga kowane bangare a kowane lokaci amma ba a gano su ba saboda suna yin rauni sosai lokacin da suka isa duniya. Ya ɗauki kimanin ƙarni ɗaya kafin a gano raƙuman nauyi kai tsaye lokacin da ƙungiyar LIGO-Virgo ta yi nasarar gano raƙuman nauyi da aka samar sakamakon haɗuwar ramukan baƙi guda biyu da ke nisan shekaru biliyan 1.3 na haske daga Duniya (1) . Wannan kuma yana nufin raƙuman ruwa da aka gano suna ɗauke da bayanai game da abin da ya faru a sararin samaniya wanda ya faru kimanin shekaru biliyan 1.3 da suka gabata.
Tun lokacin da aka fara gano shi a shekarar 2015, an samu adadi mai yawa na raƙuman nauyi har zuwa yau. Yawancinsu sun faru ne sakamakon haɗuwar ramukan baƙi guda biyu , kaɗan ne suka faru ne sakamakon karo na taurari biyu na neutron (2) . Duk raƙuman nauyi da aka gano zuwa yanzu sun faru ne a lokuta daban-daban, waɗanda suka faru ne sakamakon ramukan baƙi biyu ko taurarin neutron da ke juyawa da haɗuwa ko karo da juna (3) kuma suna da tsayin mita mai yawa, gajeriyar tsayi (a cikin millise seconds).
Duk da haka, tunda akwai yiwuwar samun tarin maɓuɓɓugan ruwa masu nauyi a sararin samaniya , don haka raƙuman ruwa masu nauyi da yawa daga ko'ina cikin duniya na iya ci gaba da ratsa duniya a kowane lokaci suna samar da bango ko hayaniya. Wannan ya kamata ya kasance mai ci gaba, bazuwar kuma ƙaramin raƙuman ruwa mai ƙarancin mita. An kiyasta cewa wani ɓangare na shi ma ya samo asali ne daga Big Bang. Ana kiransa Gravitational -wave Background (GWB), ba a gano wannan ba tukuna (3).
Amma muna iya fuskantar wani ci gaba - masu bincike a Nanohertz Observatory for Gravitational Waves (NANOGrav) na Arewacin Amurka sun ba da rahoton gano siginar ƙarancin mitoci wanda zai iya zama 'Bayanin Rage-Rage (GWB)' (4,5,6).
Ba kamar ƙungiyar LIGO-virgo ba waɗanda suka gano raƙuman nauyi daga nau'ikan ramukan baƙi daban-daban , ƙungiyar NANOGrav ta nemi raƙuman nauyi masu ɗorewa, kamar hayaniya, waɗanda aka ƙirƙira a cikin dogon lokaci ta hanyar ramuka marasa adadi a sararin samaniya . An mayar da hankali kan raƙuman nauyi masu "tsawo sosai" a ɗayan ƙarshen "bakan raƙuman nauyi".
Ba kamar haske da sauran hasken wuta na lantarki ba, ba za a iya ganin raƙuman nauyi kai tsaye da na'urar hangen nesa ba.
Ƙungiyar NANOGrav ta zaɓi millisecond pulsars (MSPs) waɗanda ke juyawa da sauri tare da kwanciyar hankali na dogon lokaci. Akwai tsarin haske mai ɗorewa daga waɗannan pulsars waɗanda ya kamata a canza su ta hanyar raƙuman nauyi. Manufar ita ce a lura da kuma sa ido kan tarin millisecond pulsars (MSP) don canje-canje masu alaƙa a lokacin isowar sigina a Duniya, don haka ƙirƙirar na'urar gano nauyin nauyi "girman galaxy " a cikin tauraronmu . Ƙungiyar ta ƙirƙiri jerin lokutan pulsar ta hanyar nazarin 47 daga cikin irin waɗannan pulsars. Arecibo Observatory da Green Bank Telescope su ne na'urorin hangen nesa na rediyo da aka yi amfani da su don aunawa.
Saitin bayanan da aka samu ya zuwa yanzu ya haɗa da MSPs 47 da sama da shekaru 12.5 na lura. Dangane da wannan, ba zai yiwu a tabbatar da gano GWB kai tsaye ba ko da yake ƙananan sigina na mitar da aka gano suna nuna hakan. Wataƙila, mataki na gaba shine haɗa ƙarin pulsars a cikin tsararru da yin nazarin su na dogon lokaci don haɓaka hankali.
Domin nazarin sararin samaniya , masana kimiyya sun dogara ne kawai da hasken lantarki kamar haske, hasken X-ray, rediyo da sauransu. Ganin cewa ba su da alaƙa da hasken lantarki, gano nauyin nauyi a shekarar 2015 ya buɗe sabuwar dama ga masana kimiyya don yin nazarin halittun sama da fahimtar sararin samaniya musamman waɗanda abubuwan da suka faru a sama waɗanda masana ilmin taurari na lantarki ba za su iya gani ba. Bugu da ƙari, ba kamar hasken lantarki ba, raƙuman ruwa masu nauyi ba sa hulɗa da abu don haka suna tafiya ba tare da wata matsala ba suna ɗauke da bayanai game da asalinsu da tushensu ba tare da wata matsala ba. (3)
Gano Bayanan Raƙuman Ruwa (GWB) zai faɗaɗa damar. Har ma yana iya yiwuwa a gano raƙuman ruwa da aka samar daga Big Bang wanda zai iya taimaka mana mu fahimci asalin sararin samaniya ta hanya mafi kyau.
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DOI: https://doi.org/10.29198/scieu/2101121
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References:
- Castelvecchi D. da Witze A., 2016. Einstein ta gravitational taguwar ruwa samu a karshe. Labaran yanayi 11 Fabrairu 2016. DOI: https://doi.org/10.1038/nature.2016.19361
- Castelvecchi D., 2020. Waɗanne abubuwa guda 50 na girgizar ƙasa suka bayyana game da sararin samaniya. Labarai Nature Published 30 Oktoba 2020. DOI: https://doi.org/10.1038/d41586-020-03047-0
- LIGO 2021. Tushen da Nau'in Raƙuman Ruwa. Akwai akan layi a https://www.ligo.caltech.edu/page/gw-sources An shiga ranar 12 ga Janairu, 2021.
- Haɗin kai NANOGrav, 2021. NANOGrav Ya Gano Yiwuwar 'Abubuwan Farko' na Fasalin Kalaman Nauyi Mai Sauƙi. Akwai akan layi a http://nanograv.org/press/2021/01/11/12-Year-GW-Background.html An shiga ranar 12 ga Janairu, 2021
- Haɗin gwiwar NANOGrav 2021. Takaitaccen Bayanin Latsa - Neman Fayil ɗin Gravitational-Wave a cikin shekaru 12.5 na bayanan NANOGrav. 11 Janairu 2021. Akwai akan layi a http://nanograv.org/assets/files/slides/AAS_PressBriefing_Jan’21.pdf
- Arzoumanian Z., et al 2020. Saitin Bayanai na NANOGrav 12.5 yr: Nemi Fagen Fasa na Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙira na Isotropic. Haruffan Jarida na Astrophysical, Juzu'i 905, Lamba 2. DOI: https://doi.org/10.3847/2041-8213/abd401
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