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Öğe High Order QCD Predictions for Inclusive Production of W Bosons in pp Collisions at √s=13 TeV(Hindawi Ltd, 2016) Ogul, Hasan; Dilsiz, Kamuran; Tiras, Emrah; Tan, Ping; Onel, Yasar; Nachtman, JanePredictions of fiducial cross sections, differential cross sections, and lepton charge asymmetry are presented for the production of W-+/- bosons with leptonic decay up to next-to-next-to-leading order (NNLO) in perturbative QCD. Differential cross sections of W-+/- bosons and W boson lepton charge asymmetry are computed as a function of lepton pseudorapidity for a defined fiducial region in pp collisions at root s = 13TeV. Numerical results of fiducial W-+/- cross section predictions are presented with the latest modern PDF models at next-to-leading order (NLO) and NNLO. It is found that the CT14 and NNPDF 3.0 predictions with NNLO QCD corrections are about 4% higher than the NLO CT14 and NNPDF 3.0 predictions while MMHT 2014 predictions with NLO QCD corrections are smaller than its NNLO QCD predictions by approximately 6%. In addition, the NNLO QCD corrections reduce the scale variation uncertainty on the cross section by a factor of 3.5. The prediction of central values and considered uncertainties are obtained using FEWZ 3.1 program.Öğe Proton Proton Çarpışmaları Sonucu Aynı Anda Üretilen Higgs Ve Vektör Bozonları?Nın 14, 27 Ve 100 Tev Kütle Merkez Enerjilerindeki Yüksek Mertebeli Kuantum Renk Dinamiği (Qcd) Tahminleri.(2023) Dilsiz, Kamuran; Tiras, Emrah; Bat, Ayse; Ogul, Hasan; Yılmaz, MeryemBu çalışmada gelecekte Avrupa Nükleer Araştırmalar Merkezi (CERN)'nde kurulması ön görülen HL-LHC, HE-LHC ve FCC gibi yüksek enerjili hızlandırıcılarda incelenmesi planlanan Higgs sinyali'nin elde edilmesini kolaylaştıracak Higgs bozonunun bir vektör bozonu ile üretiminin yüksek mertebeli QCD tesir kesitleri hesaplanmıştır. Hesaplamalar yapılırken proton çarpışmaları sonucu eş zamanlı oluşan W/Z ve Higgs üretim kanallarının birçok dallanma durumu dikkate alınmıştır. Bu bağlamda, 14, 27 ve 100 TeV kütle merkez enerjilerinde WH ve ZH üretim kanallarının dallanma durumları hesaba katılarak leading order (LO), next-to-leading order (NLO) ve next-to-NLO (NNLO) QCD tesir kesitleri hesaplanmıştır. Artan kütle merkez enerjisi ile tesir kesitinin artmasının yanı sıra, aynı enerjide yüksek mertebeli NLO ve NNLO QCD tesir kesitlerinin en düşük mertebe olan LO mertebesine kıyasla arttığı gözlemlenmiştir. Hali hazırda CERN Büyük Hadron Çarpıştırıcısı deneyleri olan CMS ve ATLAS guruplarının kullanmış oldukları eşik değerlerine yakın değerler seçilerek bir simülasyon çerçevesi oluşturulmuş, dört farklı parton dağılım fonksiyonu (PDF) ve dokuz farklı renormalizasyon ve faktörizasyon değeri kullanılarak K faktör hesaplamaları yapılmıştır. Hesaplanan K faktör değerlerinin çok küçük olması ile oluşturulan simülasyon çerçevesinin güvenilirliği test edilmiştir. Ayrıca, LO, NLO ve NNLO QCD değerlerinin PDF, scale ve alfa_S hata payları hesaplanarak scale ve toplam hata paylarının çok yüksek olduğu LO mertebesine kıyasla NLO ve NNLO QCD düzeltmelerinde çok düşük hata payları tespit edilmiştir. Böylece, yüksek mertebeli hesaplamaların ekstra partonik süreçlerin ilave edilmesiyle daha doğru tesir kesiti sonucunu vermelerinin yanı sıra ilgili üretim kanallarında düşük hata paylarına sahip oldukları tespit edilmiştir. LHC enerjilerinde (7,8,13 ve 14 TeV), HE-LHC enerjisinde (27 TeV) ve FCC-hh enerjisinde (100 TeV) hesaplanan en yüksek QCD düzeltmesi NNLO dikkate alınarak 7 TeV kütle merkez enerjisindeki veri ile elde edilen istatistiği daha yüksek enerjilerde elde edebilmek için ihtiyaç duyulan veri miktarı hesaplanmıştır. Sonuç olarak yüksek enerjilerde daha düşük veri ile düşük enerjilerdeki olay sayısının elde edilebileceği tespit edilmiştir. Özellikle, FCC-hh?nin enerjisi olan 100 TeV?de 7, 8 ve 13 TeV kütle merkez enerjilerindeki veri miktarından yaklaşık 10-15 kat daha az veri ile aynı istatistiğin elde edilebileceği görülmüştür.Öğe QCD predictions for simultaneously produced Higgs and vector bosons at s=13, 14, 27 and 100 TeV with a comprehensive study of systematic uncertainty and charge asymmetry(Springer, 2025) Dilsiz, Kamuran; Tiras, Emrah; Yilmaz, Meryem; Ogul, HasanA comprehensive study of high-order QCD cross-section for the Higgs boson that is simultaneously produced with a vector boson is presented at s = 13, 14, 27 and 100 TeV in this manuscript. The simultaneous Higgs production with a vector boson facilitates the investigation of the Higgs signal. In the calculations, three different branching states of the Higgs (tau-tau+, bb, gamma gamma) and vector bosons [W +/-(e +/-nu(nu)),Z(e-e+)] were taken into account. Here, leading order (LO), next-to-leading order (NLO), and next-to-NLO (NNLO) QCD cross-sections were calculated for these branching states. A simulation framework was built for the calculations at the TRUBA high-performance grid computing center. Then, the threshold values (selection cuts) close to the values used by the CMS and ATLAS Collaborations were selected and used on several parameters such as invariant mass, transverse momentum ( pT), pseudorapidity (eta), etc. In addition, NNPDF3.1 parton distribution functions (PDF) were used during the calculation. The results showed that the numerical value of the QCD prediction increases at NLO and NNLO as compared to the LO predictions. In addition to the higher-orders, the cross-section value increases as the center-of-mass energy increases. In addition to the QCD predictions, PDF, scale, and aS uncertainties of theQCD-predictions were also calculated to test the reliability of the highorder QCDs. The results showed that total and scale uncertainties decrease as the QCD order increases. In addition, it was found that LO total and scale uncertainties increase significantly as the center-of-mass energy increases, while NLO and NNLO scale and total uncertainties remain almost constant or show a negligible increase as the center-of-mass energy increases. This indicates that high-order QCDs not only provide more accurate results by the addition of extra partonic diagrams but also provide lower uncertainties in the relevant production channels. Furthermore, the required data that provides the exact statistics for physicsmeasurements of simultaneously produced Higgs and vector bosons as the data at 13 TeV were predicted at s = 14, 27, and 100 TeV. As a result, we found that the same statistics for accurate physics measurements can be obtained at s = 14, 27, and 100 TeV with approximately 1.1, 2.0, and 6.5 times less data than the amount of data at s = 13 TeV, respectively. In the last section of this study, Wboson charge asymmetry was computed at NNLO QCD. The lowest charge asymmetry between W + and W - was obtained at the WH(tau-tau+) decay channel and the highest charge asymmetry results were obtained at the WH(bb) decay channel.Öğe Secondary Emission Calorimetry -2(MDPI, 2022) Bilki, Burak; Dilsiz, Kamuran; Ogul, Hasan; Onel, Yasar; Southwick, David; Tiras, Emrah; Wetzel, JamesElectromagnetic calorimetry in high-radiation environments, e.g., forward regions of lepton and hadron collider detectors, is quite challenging. Although total absorption crystal calorimeters have superior performance as electromagnetic calorimeters, the availability and the cost of the radiation-hard crystals are the limiting factors as radiation-tolerant implementations. Sampling calorimeters utilizing silicon sensors as the active media are also favorable in terms of performance but are challenged by high-radiation environments. In order to provide a solution for such implementations, we developed a radiation-hard, fast and cost-effective technique, secondary emission calorimetry, and tested prototype secondary emission sensors in test beams. In a secondary emission detector module, secondary emission electrons are generated from a cathode when charged hadron or electromagnetic shower particles penetrate the secondary emission sampling module placed between absorber materials. The generated secondary emission electrons are then multiplied in a similar way as the photoelectrons in photomultiplier tubes. Here, we report on the principles of secondary emission calorimetry and the results from the beam tests performed at Fermilab Test Beam Facility as well as the Monte Carlo simulations of projected, large-scale secondary emission electromagnetic calorimeters. © 2022 by the authors.
