Tam çarmonyum mezon moleküllerine ortam etkilerinin incelenmesi
Küçük Resim Yok
Tarih
2025
Yazarlar
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Cilt Başlığı
Yayıncı
Bursa Teknik Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Egzotik hadronların deneysel olarak gözlemlenmesi, yüksek enerji fiziği alanında yürütülen kuramsal ve deneysel çalışmalara önemli katkılar sağlamıştır. Bu parçacıklar, kuark ve gluonların dinamiğinin anlaşılmasına, güçlü etkileşimlerin doğasının incelenmesine ve yeni deneysel yöntemlerin geliştirilmesine yönelik önemli bilgiler sunmaktadır. Her ne kadar deneysel olarak gözlemlenmiş olsalar da, bu egzotik parçacıkların yapıları, oluşum dinamikleri ve bulundukları ortam ile etkileşimleri tam olarak bilinmemektedir. 2020 yılında LHCb İşbirliği tarafından proton-proton çarpışmalarında gözlemlenen çift ????/???? üretimi spektrumunda, yaklaşık 6,2 GeV civarında tam çarmonyum rezonansı gözlemlenmiştir ve bu rezonans ??????????????????????(6200)0 olarak adlandırılmıştır. Bu tez çalışmasında, ??????????????????????(6200)0 rezonansının termal ortamdaki spektroskopik özellikleri, Termal Kuantum Renk Dinamiği Toplam Kuralları yöntemi kullanılarak analiz edilmiştir. ??????????????????????(6200)0 rezonansı, kuantum sayıları ???????????? = 0++ olan bir ???????????????? molekülü olarak modellenmiş ve hesaplamalarda dört boyuta kadar pertürbatif olmayan katkılar da dikkate alınarak rezonansın kütle ve leptonik bozunma sabitinin termal bağımlılığı incelenmiştir. Bu çalışmada, düşük sıcaklıklarda elde edilen egzotik durumun kütlesi ve bozunma sabitiyle ilgili sonuçlar, literatürdeki mevcut teorik ve deneysel verilerle uyumlu bulunmuştur. Hesaplamalarda literatürde çarmonyumlar için önerilen sıcaklık eşiğine daha güncel ve başarılı bir fit ilk defa bu tezde uygulanmıştır. Ortam sıcaklığının kuark-gluon plazmasına geçişin başladığı kritik sıcaklığa yaklaştığı durumda, çarmonyum molekülünün kütlesinin azalmaya başladığı, kritik sıcaklığı geçince kütlenin 2 ???????????????? eşiğinin de altına düştüğü, ancak 200 MeV'e yaklaşırken 2 ???????????????? eşiğine geri yükseldiği görülmüştür. Kütledeki azalmaya benzer şekilde leptonik bozunma sabiti de kritik sıcaklık değerine yaklaştığında azalmıştır. Buna ek olarak, kritik sıcaklığı geçince de artan kütlenin aksine bozunma sabitinde bir artma görülmemiş ve bozunma sabiti ???????? değerine yakın bir değerde sabit kalmıştır. Bu sonuçlar, gluon değişim mekanizmasının kritik sıcaklığa yaklaşırken dağılmaya başladığını, kritik sıcaklığı geçince ise tamamen koptuğunu ve ???????????????? parçacıklarının da gevşediğini, ancak 200 MeV civarında çarmonyumların yeniden toparlanarak kendilerini koruduklarını göstermektedir. Elde edilen bu sonuçlar, literatürde ağır kuarkonyumlar için önerilen davranışlarla uyumludur ve ilk kez bu tez çalışmasında teorik olarak da elde edilmiştir.
The experimental observation of exotic hadrons has made significant contributions to both theoretical and experimental studies in high-energy physics. These particles provide valuable insights into the dynamics of quarks and gluons, the nature of strong interactions, and the development of new experimental methods. Although these exotic particles have been observed experimentally, their structures, formation dynamics, and interactions with their environment are not yet fully understood. In 2020, in the double J/? production spectrum observed in proton-proton collisions by the LHCb Collaboration, a full charmonium resonance was detected around 6.2 GeV. This resonance was named ????????????¯????????¯(6200)0. In this thesis, the spectroscopic properties of the ????????????¯????????¯(6200)0 resonance in a thermal medium were analyzed using the Thermal Quantum Chromodynamics Sum Rules method. The ????????????¯????????¯(6200)0 resonance was modeled as an ???????????????? molecule with quantum numbers ???????????? = 0++, and in the calculations, non-perturbative contributions up to dimension four were also taken into account. In this study, the results obtained for the mass and decay constant of the exotic state at low temperatures were found to be consistent with existing theoretical and experimental data in the literature. A more recent and accurate fit for the temperature threshold proposed for charmonium states was used in the calculations, and this fit was applied to QCD sum rules for the first time in this thesis. It was observed that as the temperature approached the critical point, where the transition to quark-gluon plasma begins, the mass of the charmonium molecule started to decrease, eventually dropping below the 2 ???????????????? threshold. However, after crossing the critical temperature, the mass increased again, reaching the 2 ???????????????? threshold around 200 MeV. Similar to the mass, the leptonic decay constant also decreased near the critical temperature, but unlike the mass, the decay constant did not increase with increasing temperature; instead, it remained stable at a value close to that of the ????????. These results suggest that the gluon exchange mechanism begins to relax near the critical temperature and breaks down completely beyond it, and also ???????????????? particles start to dissolve. Nonetheless, around 200 MeV, the charmonium states recover and regain their structural integrity. These findings align with the behavior proposed in the literature for heavy quarkonium states and have been theoretically demonstrated for the first time in this thesis.
The experimental observation of exotic hadrons has made significant contributions to both theoretical and experimental studies in high-energy physics. These particles provide valuable insights into the dynamics of quarks and gluons, the nature of strong interactions, and the development of new experimental methods. Although these exotic particles have been observed experimentally, their structures, formation dynamics, and interactions with their environment are not yet fully understood. In 2020, in the double J/? production spectrum observed in proton-proton collisions by the LHCb Collaboration, a full charmonium resonance was detected around 6.2 GeV. This resonance was named ????????????¯????????¯(6200)0. In this thesis, the spectroscopic properties of the ????????????¯????????¯(6200)0 resonance in a thermal medium were analyzed using the Thermal Quantum Chromodynamics Sum Rules method. The ????????????¯????????¯(6200)0 resonance was modeled as an ???????????????? molecule with quantum numbers ???????????? = 0++, and in the calculations, non-perturbative contributions up to dimension four were also taken into account. In this study, the results obtained for the mass and decay constant of the exotic state at low temperatures were found to be consistent with existing theoretical and experimental data in the literature. A more recent and accurate fit for the temperature threshold proposed for charmonium states was used in the calculations, and this fit was applied to QCD sum rules for the first time in this thesis. It was observed that as the temperature approached the critical point, where the transition to quark-gluon plasma begins, the mass of the charmonium molecule started to decrease, eventually dropping below the 2 ???????????????? threshold. However, after crossing the critical temperature, the mass increased again, reaching the 2 ???????????????? threshold around 200 MeV. Similar to the mass, the leptonic decay constant also decreased near the critical temperature, but unlike the mass, the decay constant did not increase with increasing temperature; instead, it remained stable at a value close to that of the ????????. These results suggest that the gluon exchange mechanism begins to relax near the critical temperature and breaks down completely beyond it, and also ???????????????? particles start to dissolve. Nonetheless, around 200 MeV, the charmonium states recover and regain their structural integrity. These findings align with the behavior proposed in the literature for heavy quarkonium states and have been theoretically demonstrated for the first time in this thesis.
Açıklama
Anahtar Kelimeler
Fizik ve Fizik Mühendisliği, Physics and Physics Engineering
