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Design and control of spatial inverted pendulum with two degrees of freedom
No full textKARA, FIRAT/0000-0003-2082-0543The inverted pendulum systems have inherently unstable dynamics. In order to stabilize the inverted pendulum at upright position, an actuation mechanism should generate fast-reactive motions at the pivot point of the system. This paper addressed the design and control of a spatial inverted pendulum with two degrees of freedom (DOF). The first part of the study consists of designing a novel planar two-DOF (PRRRR) actuation mechanism in order to balance the spatial inverted pendulum. The system is underactuated and has inherently extreme nonlinearity and also the restrictions on the actuators. Then, in the second part, a second-order sliding-mode and a linear quadratic Gaussian (LQG) controller have been proposed to control the pendulum within the equilibrium position. Finally the simulation results evaluated in terms of the robustness, time response and stability show that the second-order sliding-mode controller is more robust and has fast response performances in re-stabilizing the spatial inverted pendulum, while LQG controller is better in terms of keeping the system in equilibrium during the long period of time
Search for a narrow resonance lighter than 200 GeV decaying to a pair of muons in proton-proton collisions at √s=13 TeV
No full textPubMed: 32302170A search is presented for a narrow resonance decaying to a pair of oppositely charged muons using root s = 13 TeV proton-proton collision data recorded at the LHC. In the 45-75 and 110-200 GeV resonance mass ranges, the search is based on conventional triggering and event reconstruction techniques. In the 11.5-45 GeV mass range, the search uses data collected with dimuon triggers with low transverse momentum thresholds, recorded at high rate by storing a reduced amount of trigger-level information. The data correspond to integrated luminosities of 137 and 96.6 fb(-1) for conventional and high-rate triggering, respectively. No significant resonant peaks are observed in the probed mass ranges. The search sets the most stringent constraints to date on a dark photon in the similar to 30-75 and 110-200 GeV mass ranges
Combined search for supersymmetry with photons in proton-proton collisions at √s =13 TeV
No full textA combination of four searches for new physics involving signatures with at least one photon and large missing transverse momentum, motivated by generalized models of gauge-mediated supersymmetry (SUSY) breaking, is presented. All searches make use of proton-proton collision data at root s = 13 TeV, which were recorded with the CMS detector at the LHC in 2016, and correspond to an integrated luminosity of 35.9 fb(-1). Signatures with at least one photon and large missing transverse momentum are categorized into events with two isolated photons, events with a lepton and a photon, events with additional jets, and events with at least one high-energy photon. No excess of events is observed beyond expectations from standard model processes, and limits are set in the context of gauge-mediated SUSY. Compared to the individual searches, the combination extends the sensitivity to gauge-mediated SUSY in both electroweak and strong production scenarios by up to 100GeV in neutralino and chargino masses, and yields the first CMS result combining various SUSY searches in events with photons at root s = 13 TeV. (C) 2019 The Author(s). Published by Elsevier B.V
Thermodynamically designed target-specific DNA probe as an electrochemical hybridization biosensor
No full textApplications of molecular techniques to elucidate identity or function using biomarkers still remain highly empirical and biosensors are no exception. In the present study, target-specific oligonucleotide probes for E. coli K12 were designed thermodynamically and applied in an electrochemical DNA biosensor setup. Biosensor was prepared by immobilization of a stem–loop structured probe, modified with a thiol functional group at its 5′ end and a biotin molecule at its 3′ end, on a gold electrode through self-assembly. Mercaptopropionic acid (MPA) was used to optimize the surface probe density of the electrode. Hybridization between the immobilized probe and the target DNA was detected via the electrochemical response of streptavidin-horseradish peroxidase in the presence of the substrate. The amperometric response showed a linear relationship with the target DNA concentration, ranging from 10 and 400 nM, with a correlation coefficient of 0.989. High selectivity and good repeatability of the biosensor showed that the thermodynamic approach to oligonucleotide probe design can be used in development of electrochemical DNA biosensors.TUBITAK (110T664
Measurement of differential cross sections and charge ratios for t-channel single top quark production in proton–proton collisions at √s=13Te
No full textPubMed: 32633732A measurement is presented of differential cross sections for t-channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13 mml:mspace> by the CMS experiment at the LHC. From a data set corresponding to an integrated luminosity of 35.9 mml:mspacefb-1, events containing one muon or electron and two or three jets are analysed. The cross section is measured as a function of the top quark transverse momentum (pT), rapidity, and polarisation angle, the charged lepton pT and rapidity, and the pT of the W boson from the top quark decay. In addition, the charge ratio is measured differentially as a function of the top quark, charged lepton, and W boson kinematic observables. The results are found to be in agreement with standard model predictions using various next-to-leading-order event generators and sets of parton distribution functions. Additionally, the spin asymmetry, sensitive to the top quark polarisation, is determined from the differential distribution of the polarisation angle at parton level to be 0.440 +/- 0.070, in agreement with the standard model prediction
Measurement of the jet mass distribution and top quark mass in hadronic decays of boosted top quarks in pp collisions at √s=13 TeV
No full textPubMed: 32501048A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at root s = 13 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb(-1). The measurement is performed in the lepton + jets channel of t (t) over bar events, where the lepton is an electron or muon. The products of the hadronic top quark decay t -> bW -> bq (q) over bar' are reconstructed as a single jet with transverse momentum larger than 400 GeV. The t (t) over bar cross section as a function of the jet mass is unfolded at the particle level and used to extract a value of the top quark mass of 172.6 +/- 2.5 GeV. A novel jet reconstruction technique is used for the first time at the LHC, which improves the precision by a factor of 3 relative to an earlier measurement. This highlights the potential of measurements using boosted top quarks, where the new technique will enable future precision measurements
The propagators for δ and δ′ potentials with time-dependent strengths
No full textWe study the time-dependent Schrodinger equation with finite number of Dirac delta and delta ' potentials with time dependent strengths in one dimension. We obtain the formal solution for generic time dependent strengths and then we study the particular cases for single delta potential and limiting cases for finitely many delta potentials. Finally, we investigate the solution of time dependent Schrodinger equation for delta ' potential with particular forms of the strengths
Bir sınıf için hareketli cephe panellerinin dinamik gün ışığı metrikleri açısından başarımı
No full textThesis (Master)--Izmir Institute of Technology, Architecture, Izmir, 2020Includes bibliographical references (leaves: 69-75)Text in English; Abstract: Turkish and EnglishAlthough the use of daylight has an important role in educational spaces, uncontrolled use of daylight can lead to some undesirable situations for occupants. It is generally accepted that recommended illuminance values change between 300 lux and 2000 lux in educational spaces. However, it is not possible to get these illuminance range at the same level during the day, as the classrooms have been used all day period. To create more satisfied daylit spaces, movable shading systems become a solution because of their ability of guiding the direct daylight in day period. To evaluate the daylight performance of movable shading systems, dynamic daylight performance metrics have been used. This thesis focuses on comparing different types of movable shading systems developed as a result of findings of dynamic daylight metrics in a classroom. A classroom in the Department of Architecture in Izmir Institute of Technology was chosen as the case room measured illuminance values. It has been found that the level of illuminance values are much higher than the generally accepted values. The classroom has been modelled virtually and analyzed on a special software programmer in order to examine the findings of the field measurement. Two different types of moveable shading systems have been suggested and used to evaluate the performance of illuminance. When the results are evaluated, it can be understood that movable shading systems have a significant role on creating satisfied spaces in educational areas. Especially, single oriented shading systems, which represented as model 1 in thesis, are more successful to control direct daylight.Eğitim yapılı ortamlarda gün ışığının kullanılmasının önemli bir rolü olmasıyla beraber, gün ışığının kontrolsüz bir şekilde kullanılması eğitim ortamında bulunanlar açısından istenmeyen durumlara yol açabilmektedir. Bu alanlarda genel olarak tavsiye edilen aydınlık değerleri 300 lux ve 2000 lux arasındadır. Diğer yandan, gün içinde aydınlık değerlerinden eşit olarak yararlanılması, sınıfların tüm gün kullanıldığı düşünüldüğünde mümkün değildir. Dolayısıyla hareketli cephe sistemleri gün içinde gün ışığından en iyi şekilde yaralanılabilmesi için bir çözümdür. Bu sistemlerin gün içindeki performansını ölçmek için ise dinamik gün ışığı metrikleri kullanılmaktadır. Bu tez, sınıflarda kullanılan farklı hareketli cephe sistemlerini dinamik gün ışığı metrikleri bakımından karşılaştırmak amacıyla yazılmıştır. Aydınlık değerlerini ölçmek için İzmir Yüksek Teknoloji Enstitüsü Mimarlık fakültesinde bulunan bir sınıf seçilmiştir ve bu sınıfın aydınlık değerlerinin literatürde kabul edilen değerlere göre yüksek olduğu gözlemlenmiştir. Sözü edilen sınıf, sanal ortamda modellenmiş ve gün ışığı similasyon programı kullanılarak analiz edilip gerçek ortamdaki verilerle karşılaştırılmıştır. Bu verileri istenilen değerlere yakınlaştırmak için iki çeşit hareketli cephe önerilmiş ve gün ışığı performansı ölçülmüştür. Sonuçlar değerlendirildiğinde hareketli cephe sistemlerinin eğitim yapılan ortamlarda kişilere daha rahat öğrenme ortamı sağladığı gözlemlenmiştir. Özellikle bu tezin birinci modelinde gösterilen tek yönelimli cephe sisteminin gün ışığından en iyi şekilde yararlanılmasında başarılı olduğu sonucuna ulaşılmıştır
Gelecekteki konut tasarımları için geleneksel yapılarda mimari tasarım parametrelerinin karşılaştırılması
No full textThesis (Doctoral)--Izmir Institute of Technology, Architecture, Izmir, 2020Includes bibliographical references (leaves: 150-156)Text in English; Abstract: Turkish and EnglishArchitectural studies re-orient through traditional architecture because of the energy crisis. The purpose of this study is to examine the architectural design parameters of traditional dwellings in terms of energy efficiency for future housing design in a hot humid climate. The case of this study is the 19th Century İzmir Houses. Two base case buildings with two and single-story were determined. Onsite measurements were taken from these buildings to identify the building material properties and to understand their thermal behavior. They were modeled and simulated with the DesignBuilder energy simulation program. The calibration and validation processes were conducted on these models. Two and single-story 114 types of İzmir Houses were modeled using the base drawings of the actual examples of these types and the validated material properties of the base case buildings in two different settlements where they are most frequently seen. The energy consumptions of these models were simulated. The statistical analyses were applied to examine the relationship between the source energy consumption per square meter and the design parameters of İzmir Houses. The design parameters such as the location of the hall, plan type, the existence of the basement, window to wall ratio, wall to floor ratio, window to floor ratio, total building area, wall to volume ratio, settlement pattern were found effective on the building energy performance. The least energy-consuming two-story İzmir houses type has a basement and side hall plan while the single-story house has a basement and central hall plan.Mimari çalışmalar, enerji krizi nedeniyle geleneksel mimariye yönelmektedir. Bu çalışmanın amacı sıcak ve nemli iklimdeki geleneksel konutların enerji etkinliğe ilişkin mimari tasarım parametrelerini gelecekteki konut tasarımları için irdelemektir. Bu çalışmanın örneği 19. Yüzyıl İzmir Evleri'dir. İki ve tek katlı iki temel örnek bina tespit edilmiştir. Yapı malzemelerinin özelliklerini belirlemek ve bu tür binaların termal davranışlarını anlamak için bu binalardan yerinde ölçümler alınmıştır. Bu binalar Design Builder enerji simülasyon programı ile modellenmiş ve simüle edilmiştir. Bu modellerde kalibrasyon ve validasyon işlemleri gerçekleştirilmiştir. İki ve tek katlı 114 tip İzmir Konutu en çok görüldükleri iki farklı yerleşimde, bu tiplerin gerçek örneklerinin temel çizimleri ve temel örnek binaların valide edilmiş malzeme özellikleri kullanılarak modellenmiştir. Bu modellerin enerji tüketimi simüle edilmiştir. Metrekare başına düşen kaynak (birincil) enerji tüketimi ile İzmir Evleri'nin tasarım parametreleri arasındaki ilişkiyi incelemek amacıyla istatistiksel analizler yapılmıştır. Holün konumu, plan tipi, bodrumun varlığı, pencere duvar oranı, duvar taban oranı, pencere-taban oranı, toplam bina alanı, duvar hacim oranı, yerleşim düzeni gibi tasarım parametreleri bina enerji performansı üzerinde etkili bulunmuştur. En az enerji tüketen iki katlı İzmir ev tipi bodrum ve yan hollü plana sahipken, tek katlı İzmir evi bodrum ve merkezi hollü plana sahiptir
Evidence for Top Quark Production in Nucleus-Nucleus Collisions
No full textMartinez Ruiz del Arbol, Pablo/0000-0002-7737-5121; Lotfy Abdelfattah Ahmad, Ahmad/0000-0003-4681-0079; Arneodo, Michele/0000-0002-7790-7132; Redondo, Ignacio/0000-0003-3737-4121; Shchutska, Lesya/0000-0003-0700-5448; Collard, Caroline/0000-0002-5230-8387; Consuegra Rodriguez, Sandra/0000-0002-1383-1837; Sosa Ricardo, Rafael Eduardo/0000-0002-2240-6699; Belforte, Stefano/0000-0001-8443-4460; Abbiendi, Giovanni/0000-0003-4499-7562; Jafari, Abideh/0000-0001-7327-1870; Mitra, Soureek/0000-0002-3060-2278; Ghosh, Saranya/0000-0001-6717-0803; Tavolaro, Vittorio Raoul/0000-0003-2518-7521; Meridiani, Paolo/0000-0002-8480-2259; Saka, Halil/0000-0001-7616-2573; Fernandez Perez Tomei, Thiago Rafael/0000-0002-1809-5226; d'Enterria, David/0000-0002-5754-4303; Costa, Salvatore/0000-0001-9919-0569; Ecklund, Karl/0000-0002-6976-4637; Fernandez Ramos, Juan Pablo/0000-0002-0122-313X; Litov, Leandar/0000-0002-8511-6883; Watson, Ian/0000-0003-2141-3413; Botta, Cristina/0000-0002-8072-795X; Bloom, Kenneth/0000-0002-4272-8900; Delaere, Christophe/0000-0001-8707-6021; Mousa, Jehad/0000-0002-2978-2718; Ruiz Jimeno, Alberto/0000-0002-3639-0368; Galli Mercadante, Pedro/0000-0001-8333-4302; Waltenberger, Wolfgang/0000-0002-6215-7228; Androsov, Konstantin/0000-0003-2694-6542; Calligaris, Luigi/0000-0002-9951-9448; Tully, Christopher/0000-0001-6771-2174; David, Pieter/0000-0001-9260-9371; Lange, Clemens/0000-0002-3632-3157; Taylor, Lucas/0000-0002-6584-2538; Wu, Zhenbin/0000-0003-2165-9501; Kyberd, Paul/0000-0002-7353-7090; Piperov, Stefan/0000-0002-9266-7819; Konecki, Marcin/0000-0001-9482-4841; Caputo, Claudio/0000-0001-7522-4808; Levchuk, Leonid/0000-0001-5889-7410; Sharma, Ram Krishna/0000-0003-1181-1426; Joshi, Yagya/0000-0002-0651-1878; Snoeys, Walter/0000-0003-3541-9066; Li, Qiang/0000-0002-8290-0517; FORD, WILLIAM/0000-0001-8703-6943; Tholen, Heiner/0000-0002-2299-2421; Dragicevic, Marko/0000-0003-1967-6783; Martelli, Arabella/0000-0003-3530-2255; Cepeda, Maria/0000-0002-6076-4083; Faccioli, Pietro/0000-0003-1849-6692; Gandrajula, Reddy Pratap/0000-0001-9053-3182; Viliani, Lorenzo/0000-0002-1909-6343; Feld, Lutz/0000-0001-9813-8646; lee, jason/0000-0002-2153-1519; Ruiz, Jose/0000-0002-3306-0363; Bhandari, Rohan/0000-0001-5888-955X; Frankenthal, Andre/0000-0002-2583-5982; Palencia Cortezon, Jose Enrique/0000-0001-8264-0287; Hamel de Monchenault, Gautier/0000-0002-3872-3592; Sciacca, Crisostomo/0000-0002-8412-4072; Kasemann, Matthias/0000-0002-0429-2448; Novaes, Sergio/0000-0003-0471-8549; Landsberg, Greg/0000-0002-4184-9380; Mora Herrera, Maria Clemencia/0000-0003-3915-3170; Bravo, Cameron/0000-0003-1102-8247; Bartok, Marton/0000-0002-4440-2701; Lucchini, Marco Toliman/0000-0002-7497-7450; Pfeiffer, Andreas/0000-0001-5328-448X; Kothekar, Kunal/0000-0001-5102-4326; Padula, Sandra S./0000-0003-3071-0559; Pantaleo, Felice/0000-0003-3266-4357; Vilela Pereira, Antonio/0000-0003-3177-4626; Wardle, Nicholas/0000-0003-1344-3356; Chapon, Emilien/0000-0001-6968-9828; Monaco, Vincenzo/0000-0002-3617-2432; Buchanan, James/0000-0001-8207-5556; Khvedelidze, Arsen/0000-0002-5953-0140; Schonenberger, Myriam/0000-0002-6508-5776; Heindl, Maximilian/0000-0002-2831-463X; Haller, Johannes/0000-0001-9347-7657; Lezki, Samet/0000-0002-6909-774X; Benato, Lisa/0000-0001-5135-7489; Ptochos, Fotios/0000-0002-3432-3452; Ebrahimi, Aliakbar/0000-0003-4472-867X; Harb, Ali/0000-0001-5750-3889; Conway, John/0000-0003-2719-5779; Zenz, Seth/0000-0002-9720-1794; Dogra, Sunil/0000-0002-0812-0758; Steggemann, Jan/0000-0003-4420-5510; Usai, Emanuele/0000-0001-9323-2107; Lethuillier, Morgan/0000-0001-6185-2045; Attia Mahmoud, Mohammed/0000-0001-8692-5458; Malik, Sudhir/0000-0002-6356-2655; Giacomelli, Paolo/0000-0002-6368-7220; Poudyal, Nabin/0000-0003-4278-3464; Zanetti, Marco/0000-0003-4281-4582; Azzi, Patrizia/0000-0002-3129-828X; Tinoco Mendes, Andre David/0000-0001-5854-7699; Hurtado Anampa, Kenyi/0000-0002-9779-3566; Rolandi, Luigi (Gigi)/0000-0002-0635-274X; Zuolo, Davide/0000-0003-3072-1020; CHANG, PAO-TI/0000-0003-4064-388X; Van Onsem, Gerrit/0000-0002-1664-2337; Klein, Daniel/0000-0001-9143-5162; Zucchetta, Alberto/0000-0003-0380-1172; Dharmaraatna, Welathantri/0000-0002-6366-837X; Cadamuro, Luca/0000-0001-8789-610X; Paulini, Manfred/0000-0002-6714-5787; Popov, Andrey/0000-0002-1207-0984; Giammanco, Andrea/0000-0001-9640-8294; Moraes, Arthur/0000-0002-5157-5686; Belloni, Alberto/0000-0002-1727-656X; Everaerts, Pieter/0000-0003-3848-324X; Rabbertz, Klaus/0000-0001-7040-9846; Vami, Tamas Almos/0000-0002-0959-9211; Smith, Wesley/0000-0003-3195-0909; Ligabue, Franco/0000-0002-1549-7107; Lawhorn, Jay/0000-0002-8597-9259; Bols, Emil Sorensen/0000-0002-8564-8732; Schulte, Jan-Frederik/0000-0003-4421-680X; Yazgan, Efe/0000-0001-5732-7950; Murillo Quijada, Javier Alberto/0000-0003-4933-2092; Kim, Tae Jeong/0000-0001-8336-2434; Rizzi, Andrea/0000-0002-4543-2718; Keaveney, James/0000-0003-0766-5307; Fernandez Menendez, Javier/0000-0002-5213-3708; Hall, Geoffrey/0000-0002-6299-8385; Verweij, Marta/0000-0002-1504-3420; Sanchez-Hernandez, Alberto/0000-0001-9548-0358; Fernandez Bedoya, Cristina/0000-0001-8057-9152; Leonardo, Nuno/0000-0002-9746-4594; Belyaev, Alexander/0000-0002-1733-4408; Lange, Johannes/0000-0001-7513-6330; Raidal, Martti/0000-0001-7040-9491; Fiorendi, Sara/0000-0003-3273-9419; Myronenko, Volodymyr/0000-0002-3984-4732; Golf, Frank/0000-0003-3567-9351; Heath, Helen/0000-0001-6576-9740; Blekman, Freya/0000-0002-7366-7098; Goldstein, Joel/0000-0003-1591-6014; Chauhan, Shubhanshu/0000-0002-6544-5794; Manca, Elisabetta/0000-0001-8946-655X; Hernandez Calama, Jose Maria/0000-0001-6436-7547; Massironi, Andrea/0000-0002-0782-0883; Sharma, Varun/0000-0003-1287-1471; Heikkila, Jaana/0000-0002-0538-1469; Wang, Dayong/0000-0002-9013-1199; Rossi, Biagio/0000-0002-0807-8772; Krikler, Benjamin/0000-0001-9712-0030; Zhang, Zhicai/0000-0002-1630-0986; De Guio, Federico/0000-0001-5927-8865; CUFFIANI, Marco/0000-0003-2510-5039; Moon, Chang-Seong/0000-0001-8229-7829; Tapper, Alexander/0000-0003-4543-864X; Shah, Aashaq/0000-0002-6157-2016; Alves, Gilvan/0000-0002-8369-1446; Gonzalez Caballero, Isidro/0000-0002-8087-3199; D'Hondt, Jorgen/0000-0002-9598-6241; Spagnolo, Paolo/0000-0001-7962-5203; Polikarpov, Sergey/0000-0001-6839-928X; ASILAR, Ece/0000-0001-5680-599X; Nguyen, Thong Q./0000-0003-3954-5131; Wilson, Graham/0000-0003-0917-4763; Gerosa, Raffaele/0000-0001-8359-3734; Canelli, Florencia/0000-0001-6361-2117; Vischia, Pietro/0000-0002-7088-8557; Trevisani, Nicolo/0000-0002-5223-9342; Zghiche, Amina/0000-0002-1178-1450; Gonzalez Lopez, Oscar/0000-0002-4532-6464; Vartak, Adish/0000-0003-1507-1365; Rappoccio, Salvatore/0000-0002-5449-2560; Dominguez, Aaron/0000-0002-7420-5493; Backhaus, Malte/0000-0002-5888-2304; Ramirez Garcia, Mateo/0000-0002-4564-3822; Shevchenko, Rostyslav/0000-0002-3236-4090; Mitselmakher, Guenakh/0000-0001-5745-3658; Pieri, Marco/0000-0003-3303-6301; Cassese, Antonio/0000-0003-3010-4516; Blumenfeld, Barry/0000-0003-1150-1735; Ricci-Tam, Francesca/0000-0001-9750-7702; Tonelli, Guido Emilio/0000-0003-2606-9156; Brigljevic, Vuko/0000-0001-5847-0062; Petrucciani, Giovanni/0000-0003-0889-4726; Bortignon, Pierluigi/0000-0002-5360-1454; Gershtein, Yuri/0000-0002-4871-5449; Duarte, Javier Mauricio/0000-0002-5076-7096; Goy Lopez, Silvia/0000-0001-6508-5090; Benitez, Jose Feliciano/0000-0002-2633-6712; Mnich, Joachim/0000-0001-7242-8426; Palladino, Vito/0000-0002-9786-9620; Csanad, Mate/0000-0002-3154-6925; Habibullah, Redwan/0000-0002-3161-8300; Garcia, Francisco/0000-0002-4023-7964; Soares, Mara/0000-0001-9676-6059; Bernardes, Cesar Augusto/0000-0001-5790-9563; Dewanjee, Ram Krishna/0000-0001-6645-6244; Schwandt, Joern/0000-0002-0052-597X; Tavernier, Stefaan/0000-0002-6792-9522; Sagir, Sinan/0000-0002-2614-5860; Starling, Elizabeth/0000-0002-4399-7213; Mundim, Luiz/0000-0001-9964-7805; Tosi, Nicolo/0000-0002-0474-0247; Ulrich, Ralf/0000-0002-2535-402X; Kole, Gouranga/0000-0002-3285-1497; Robert, Schoefbeck/0000-0002-2332-8784; YOON, INSEOK/0000-0002-3491-8026; Naimuddin, Md/0000-0003-4542-386X; Reis, Thomas/0000-0003-3703-6624; Vormwald, Benedikt/0000-0003-2607-7287; Sculac, Toni/0000-0002-9578-4105; Schroder, Matthias/0000-0001-8058-9828; Felcini, Marta/0000-0002-2051-9331; Sznajder, Andre/0000-0001-6998-1108; Cavallari, Francesca/0000-0002-1061-3877; Krintiras, Georgios Konstantinos/0000-0002-0380-7577; Marzocchi, Badder/0000-0001-6687-6214; Grandi, Claudio/0000-0001-5998-3070; Lo Meo, Sergio/0000-0003-3249-9208; Pastrone, Nadia/0000-0001-7291-1979; Migliore, Ernesto/0000-0002-2271-5192; Mrenna, Stephen/0000-0001-8731-160X; Klanner, Robert/0000-0002-7004-9227; Gutsche, Oliver/0000-0002-8015-9622; Dallavalle, Gaetano Marco/0000-0002-8614-0420; Kiminsu, Ugur/0000-0001-6940-7800; Beaudette, Florian/0000-0002-1194-8556; Zorbakir, Ibrahim Soner/0000-0002-5962-2221; Ince Lezki, Merve/0000-0001-6907-0195; Navarro-Tobar, Alvaro/0000-0003-3606-1780; Kreczko, Luke/0000-0003-2341-8330; Heredia de la Cruz, Ivan/0000-0002-8133-6467; Forthomme, Laurent/0000-0002-3302-336X; Cristella, Leonardo/0000-0002-4279-1221; Bhowmik, Sandeep/0000-0003-1260-973X; Ivanov, Andrew/0000-0002-9270-5643; Garutti, Erika/0000-0003-0634-5539; Haddad, Yacine/0000-0003-4916-7752; Bodek, Arie/0000-0003-0409-0341; Grohsjean, Alexander/0000-0003-0748-8494; Tosi, Silvano/0000-0002-7275-9193; Staiano, Amedeo/0000-0003-1803-624X; Govoni, Pietro/0000-0002-0227-1301; Amendola, Chiara/0000-0002-4359-836X; ALCARAZ MAESTRE, JUAN/0000-0003-0914-7474; Alverson, George/0000-0001-6651-1178PubMed: 33315428Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10(-6) sec, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon center-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production (sigma(t (t) over bar)) via the selection of charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, sigma(t (t) over bar) = 2.54(-0.74)(+0.84) and 2.03(-0.64)(+0.71) mu b, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.BMBWF (Austria); FWF (Austria)Austrian Science Fund (FWF); FNRS (Belgium)Fonds de la Recherche Scientifique - FNRS; FWO (Belgium)FWO; CNPq (Brazil)National Council for Scientific and Technological Development (CNPq); CAPES (Brazil)CAPES; FAPERJ (Brazil)Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ); FAPERGS (Brazil)Foundation for Research Support of the State of Rio Grande do Sul (FAPERGS); FAPESP (Brazil)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); MES (Bulgaria); CERN; CAS (China)Chinese Academy of Sciences; MoST (China)Ministry of Science and Technology, China; NSFC (China)National Natural Science Foundation of China (NSFC); COLCIENCIAS (Colombia)Departamento Administrativo de Ciencia, Tecnologia e Innovacion Colciencias; MSES (Croatia); CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); MoER (Estonia); ERC IUT (Estonia)Estonian Research Council; PUT (Estonia); ERDF (Estonia)European Union (EU); Academy of Finland (Finland)Academy of Finland; MEC (Finland); HIP (Finland); CEA (France)French Atomic Energy Commission; CNRS/IN2P3 (France)Centre National de la Recherche Scientifique (CNRS); BMBF (Germany)Federal Ministry of Education & Research (BMBF); DFG (Germany)German Research Foundation (DFG); HGF (Germany); GSRT (Greece)Greek Ministry of Development-GSRT; NKFIA (Hungary); DAE (India)Department of Atomic Energy (DAE); DST (India)Department of Science & Technology (India); IPM (Iran); SFI (Ireland)Science Foundation Ireland; INFN (Italy)Istituto Nazionale di Fisica Nucleare (INFN); MSIP (Republic of Korea); NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE (Malaysia); UM (Malaysia); BUAP (Mexico); CINVESTAV (Mexico); CONACYT (Mexico)Consejo Nacional de Ciencia y Tecnologia (CONACyT); LNS (Mexico); SEP (Mexico); UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE (Poland); NSC (Poland); FCT (Portugal)Portuguese Foundation for Science and Technology; JINR (Dubna); MON (Russia); RosAtom (Russia); RAS (Russia)Russian Academy of Sciences; RFBR (Russia)Russian Foundation for Basic Research (RFBR); NRC KI (Russia); MESTD (Serbia); SEIDI (Spain); CPAN (Spain); PCTI (Spain); FEDER (Spain)European Union (EU); MOSTR (Sri Lanka); MST (Taipei); ThEPCenter (Thailand); IPST (Thailand); STAR (Thailand); NSTDA (Thailand); TUBITAK (Turkey)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); TAEK (Turkey)Ministry of Energy & Natural Resources - Turkey; NASU (Ukraine); STFC (United Kingdom)Science & Technology Facilities Council (STFC); DOE (USA)United States Department of Energy (DOE); NSF (USA)National Science Foundation (NSF)MOS (Montenegro); CEA and CNRS/IN2P3 (France); We congratulate our colleagues in the CERN accelerator departments for the excellent performance of the LHC and thank the technical and administrative staffs at CERN and at other CMS institutes for their contributions to the success of the CMS effort. In addition, we gratefully acknowledge the computing centers and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC and the CMS detector provided by the following funding agencies: BMBWF and FWF (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, FAPERGS, and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RIF (Cyprus); SENESCYT (Ecuador); MoER, ERC IUT, PUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF (Germany); GSRT (Greece); NKFIA (Hungary); DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); MSIP and NRF (Republic of Korea); MES (Latvia); LAS (Lithuania); MOE and UM (Malaysia); BUAP, CINVESTAV, CONACYT, LNS, SEP, and UASLP-FAI (Mexico); MOS (Montenegro); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS, RFBR, and NRC KI (Russia); MESTD (Serbia); SEIDI, CPAN, PCTI, and FEDER (Spain); MOSTR (Sri Lanka); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR, and NSTDA (Thailand); TUBITAK and TAEK (Turkey); NASU (Ukraine); STFC (United Kingdom); DOE and NSF (USA)