Institution
Sofia University
Education•Sofia, Bulgaria•
About: Sofia University is a education organization based out in Sofia, Bulgaria. It is known for research contribution in the topics: Large Hadron Collider & Standard Model. The organization has 8533 authors who have published 15730 publications receiving 306320 citations. The organization is also known as: University of Sofia & BFUS.
Topics: Large Hadron Collider, Standard Model, Population, Lepton, Laser
Papers published on a yearly basis
Papers
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TL;DR: The standard model (SM) production of four top quarks in proton-proton collisions is studied by the CMS Collaboration, with limits set on the production of a heavy scalar or pseudoscalar boson in Type-II two-Higgs-doublet and simplified dark matter models.
Abstract: The standard model (SM) production of four top quarks ($\text {t} {}{\overline{\text {t}}} \text {t} {}{\overline{\text {t}}} $) in proton–proton collisions is studied by the CMS Collaboration. The data sample, collected during the 2016–2018 data taking of the LHC, corresponds to an integrated luminosity of 137$\,\text {fb}^{-1}$ at a center-of-mass energy of 13$\,\text {TeV}$. The events are required to contain two same-sign charged leptons (electrons or muons) or at least three leptons, and jets. The observed and expected significances for the $\text {t} {}{\overline{\text {t}}} \text {t} {}{\overline{\text {t}}} $ signal are respectively 2.6 and 2.7 standard deviations, and the $\text {t} {}{\overline{\text {t}}} \text {t} {}{\overline{\text {t}}} $ cross section is measured to be $12.6^{+5.8}_{-5.2}\,\text {fb} $. The results are used to constrain the Yukawa coupling of the top quark to the Higgs boson, $y_{\text {t}}$, yielding a limit of $|y_{\text {t}}/y_{\text {t}}^{\mathrm {SM}} | < 1.7$ at $95\%$ confidence level, where $y_{\text {t}}^{\mathrm {SM}}$ is the SM value of $y_{\text {t}}$. They are also used to constrain the oblique parameter of the Higgs boson in an effective field theory framework, $\hat{H}<0.12$. Limits are set on the production of a heavy scalar or pseudoscalar boson in Type-II two-Higgs-doublet and simplified dark matter models, with exclusion limits reaching 350–470$\,\text {GeV}$ and 350–550$\,\text {GeV}$ for scalar and pseudoscalar bosons, respectively. Upper bounds are also set on couplings of the top quark to new light particles.
97 citations
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TL;DR: In this paper, a key technology for moving toward a promising energy scenario based on renewable (regenerative) energy resources in that wind and solar energy can be stored and stored and...
Abstract: Electrochemical water splitting is a key technology for moving toward a promising energy scenario based on renewable (regenerative) energy resources in that wind and solar energy can be stored and ...
97 citations
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Vardan Khachatryan, Albert M. Sirunyan, Armen Tumasyan, Wolfgang Adam1 +2128 more•Institutions (146)
TL;DR: In this paper, the results of a search for the rare decay of the top quark that results in a charm quark and an SM Higgs boson, t to ch, were presented in terms of the H and A production cross sections times branching fractions.
Abstract: Searches are presented for heavy scalar (H) and pseudoscalar (A) Higgs bosons posited in the two doublet model (2HDM) extensions of the standard model (SM). These searches are based on a data sample of pp collisions collected with the CMS experiment at the LHC at a center-of-mass energy of sqrt(s) = 8 TeV and corresponding to an integrated luminosity of 19.5 inverse femtobarns. The decays H to hh and A to Zh, where h denotes an SM-like Higgs boson, lead to events with three or more isolated charged leptons or with a photon pair accompanied by one or more isolated leptons. The search results are presented in terms of the H and A production cross sections times branching fractions and are further interpreted in terms of 2HDM parameters. We place 95% CL cross section upper limits of approximately 7 pb on sigma times B for H to hh and 2 pb for A to Zh. Also presented are the results of a search for the rare decay of the top quark that results in a charm quark and an SM Higgs boson, t to ch, the existence of which would indicate a nonzero flavor-changing Yukawa coupling of the top quark to the Higgs boson. We place a 95% CL upper limit of 0.56% on B(t to ch).
97 citations
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TL;DR: The testing of cytotoxic activity suggests that these compounds may be endowed with important antiviral properties, and it is interesting to note that the Pd(II)-benzyl bis(thiosemicarbazone) complex, 2, exhibits a significant activity against acyclovir-resistant viruses R-100 ( HSV 1) and PU (HSV 2) with an in vitro selectivity index (SI) of 8.0.
97 citations
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Vardan Khachatryan1, Albert M. Sirunyan1, Armen Tumasyan1, Wolfgang Adam +2274 more•Institutions (154)
TL;DR: In this article, the production yields of quarkonium states are measured through their decays into muon pairs in the CMS detector, in PbPb and pp collisions at the centre-of-mass energy per nucleon pair of 2.76 TeV.
97 citations
Authors
Showing all 8600 results
Name | H-index | Papers | Citations |
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Michael Tytgat | 134 | 1449 | 94133 |
Leander Litov | 133 | 1424 | 92713 |
Eric Conte | 132 | 1206 | 84593 |
Georgi Sultanov | 132 | 1493 | 93318 |
Plamen Iaydjiev | 131 | 1285 | 87958 |
Anton Dimitrov | 130 | 1236 | 86919 |
Jordan Damgov | 129 | 1195 | 85490 |
Borislav Pavlov | 129 | 1245 | 86458 |
Jean-Laurent Agram | 128 | 1221 | 84423 |
Cristina Botta | 128 | 1160 | 79070 |
Jean-Charles Fontaine | 128 | 1190 | 84011 |
Peicho Petkov | 128 | 1111 | 83495 |
Muhammad Ahmad | 128 | 1187 | 79758 |
Roumyana Hadjiiska | 126 | 1003 | 73091 |
Mircho Rodozov | 124 | 972 | 70519 |