Now showing items 21-40 of 40

    • A Precise Determination of \(\alpha_s\) From LEP Thrust Data Using Effective Field Theory 

      Becher, Thomas; Schwartz, Matthew D (Springer Verlag, 2008)
      Starting from a factorization theorem in Soft-Collinear Effective Theory, the thrust distribution in e\(^+\)e\(^-\) collisions is calculated including resummation of the next-to-next-to-next-to leading logarithms. This is ...
    • Precision direct photon spectra at high energy and comparison to the 8 TeV ATLAS data 

      Schwartz, Matthew D (Springer Nature, 2016)
      The direct photon spectrum is computed to the highest currently available precision and compared to ATLAS data from 8 TeV collisions at the LHC. The prediction includes threshold resummation at next-to-next-to-next-to-leading ...
    • Precision Jet Substructure from Boosted Event Shapes 

      Feige, Ilya Eric Alexander; Schwartz, Matthew D; Stewart, Iain W.; Thaler, Jesse (American Physical Society (APS), 2012)
      Jet substructure has emerged as a critical tool for LHC searches, but studies so far have relied heavily on shower Monte Carlo simulations, which formally approximate QCD at leading-log level. We demonstrate that systematic ...
    • Pure Samples of Quark and Gluon Jets at the LHC 

      Gallicchio, Jason; Schwartz, Matthew D (Springer Verlag, 2011)
      Having pure samples of quark and gluon jets would greatly facilitate the study of jet properties and substructure, with many potential standard model and new physics applications. To this end, we consider multijet and ...
    • Quark and Gluon Jet Substructure 

      Gallicchio, Jason; Schwartz, Matthew D (Springer Science + Business Media, 2013)
      Distinguishing quark-initiated jets from gluon-initiated jets has the potential to significantly improve the reach of many beyond-the-standard model searches at the Large Hadron Collider and to provide additional tests of ...
    • Quark and Gluon Tagging at the LHC 

      Gallicchio, Jason; Schwartz, Matthew D (American Physical Society, 2011)
      Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing ...
    • Removing phase-space restrictions in factorized cross sections 

      Feige, Ilya Eric Alexander; Schwartz, Matthew D; Yan, Kai (American Physical Society (APS), 2015)
      Factorization in gauge theories holds at the amplitude or amplitude-squared level for states of given soft or collinear momenta. When performing phase-space integrals over such states, one would generally like to avoid ...
    • Resummation and NLO Matching of Event Shapes with Effective Field Theory 

      Schwartz, Matthew D (American Physical Society, 2008)
      The resummed differential thrust rate in \(e^+e^-\) annihilation is calculated using Soft-Collinear Effective Theory (SCET). The resulting distribution in the two-jet region \((T \sim 1)\) is found to agree with the ...
    • Resummation for W and Z Production at Large p T 

      Becher, Thomas; Lorentzen, Christian; Schwartz, Matthew D (American Physical Society (APS), 2012)
      Soft-Collinear Effective theory is used to perform threshold resummation for W and Z production at large transverse momentum to next-to-next-to-leading logarithmic accuracy including matching to next-to-leading fixed-order ...
    • Resummation of Heavy Jet Mass and Comparison to LEP Data 

      Chen, Yang-Ting; Schwartz, Matthew D (Springer Verlag, 2010)
      The heavy jet mass distribution in e\(^+\)e\(^−\) collisions is computed to next-to-next-to-next-to leading logarithmic (N\(^3\)LL) and next-to-next-to leading fixed order accuracy (NNLO). The singular terms predicted from ...
    • Resummation of Jet Mass at Hadron Colliders 

      Chien, Yang-Ting; Kelley, Randall S; Schwartz, Matthew D; Zhu, Hua Xing (American Physical Society (APS), 2013)
      A method is developed for calculating the jet mass distribution at hadron colliders using an expansion about the kinematic threshold. In particular, we consider the mass distribution of jets of size R produced in association ...
    • Seeing in Color: Jet Superstructure 

      Gallicchio, Jason; Schwartz, Matthew D (American Physical Society, 2010)
      A new class of observables is introduced which aims to characterize the superstructure of an event, that is, features, such as color flow, which are not determined by the jet four-momenta alone. Traditionally, an event is ...
    • Streamlining resummed QCD calculations using Monte Carlo integration 

      Farhi, David; Feige, Ilya Eric Alexander; Freytsis, Marat; Schwartz, Matthew D (Springer Nature, 2016)
      Some of the most arduous and error-prone aspects of precision resummed calculations are related to the partonic hard process, having nothing to do with the resummation. In particular, interfacing to parton-distribution ...
    • Threshold hadronic event shapes with effective field theory 

      Kelley, Randall; Schwartz, Matthew D (American Physical Society (APS), 2011)
      Hadronic event shapes, that is, event shapes at hadron colliders, could provide a great way to test both standard and non-standard theoretical models. However, they are significantly more complicated than event shapes at ...
    • Threshold Hadronic Event Shapes with Effective Field Theory 

      Kelley, Randall; Schwartz, Matthew D (American Physical Society, 2011)
      Hadronic event shapes, that is, event shapes at hadron colliders, could provide a great way to test both standard and nonstandard theoretical models. However, they are significantly more complicated than event shapes at ...
    • Top Condensation as a Motivated Explanation of the Top Forward-Backward Asymmetry 

      Cui, Yanou; Han, Zhenyu; Schwartz, Matthew D (Springer Verlag, 2011)
      Models of top condensation can provide both a compelling solution to the hierarchy problem as well as an explanation of why the top-quark mass is large. The spectrum of such models, in particular topcolor-assisted technicolor, ...
    • Top-Tagging: A Method for Identifying Boosted Hadronic Tops 

      Kaplan, David; Rehermann, Keith; Schwartz, Matthew D; Tweedie, Brock (American Physical Society, 2008)
      A method is introduced for distinguishing top jets (boosted, hadronically decaying top quarks) from light quark and gluon jets using jet substructure. The procedure involves parsing the jet cluster to resolve its subjets, ...
    • Towards an understanding of the correlations in jet substructure 

      Adams, D.; Arce, A.; Asquith, L.; Backovic, M.; Barillari, T.; Berta, P.; Bertolini, D.; Buckley, A.; Butterworth, J.; Camacho Toro, R. C.; Caudron, J.; Chien, Y.-T.; Cogan, J.; Cooper, B.; Curtin, D.; Debenedetti, C.; Dolen, J.; Eklund, M.; El Hedri, S.; Ellis, S. D.; Embry, T.; Ferencek, D.; Ferrando, J.; Fleischmann, S.; Freytsis, M; Giulini, M.; Han, Z.; Hare, D.; Harris, P.; Hinzmann, A.; Hoing, R.; Hornig, A.; Jankowiak, M.; Johns, K.; Kasieczka, G.; Kogler, R.; Lampl, W.; Larkoski, A. J.; Lee, C.; Leone, R.; Loch, P.; Lopez Mateos, David; Lou, H. K.; Low, M.; Maksimovic, P.; Marchesini, I.; Marzani, S.; Masetti, L.; McCarthy, R.; Menke, S.; Miller, D. W.; Mishra, K.; Nachman, B.; Nef, P.; O’Grady, F. T.; Ovcharova, A.; Picazio, A.; Pollard, C.; Potter-Landua, B.; Potter, C.; Rappoccio, S.; Rojo, J.; Rutherfoord, J.; Salam, G. P.; Schabinger, R. M.; Schwartzman, A.; Schwartz, Matthew D; Shuve, B.; Sinervo, P.; Soper, D.; Sosa Corral, D. E.; Spannowsky, M.; Strauss, E.; Swiatlowski, M.; Thaler, J.; Thomas, C.; Thompson, E.; Tran, N. V.; Tseng, J.; Usai, E.; Valery, L.; Veatch, J.; Vos, M.; Waalewijn, W.; Wacker, J.; Young, C. (Springer Science + Business Media, 2015)
      Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order ...
    • The Two-loop Hemisphere Soft Function 

      Kelley, Randall; Schabinger, Robert; Schwartz, Matthew D; Zhu, Hua (American Physical Society, 2011)
      The hemisphere soft function is calculated to order \(\alpha_s^2\). This is the first multi-scale soft function calculated to two loops. The renormalization scale dependence of the result agrees exactly with the prediction ...
    • W-Jet Tagging: Optimizing the Identification of Boosted Hadronically-Decaying W Bosons 

      Cui, Yanou; Han, Zhenyu; Schwartz, Matthew D (American Physical Society, 2011)
      A method is proposed for distinguishing highly boosted hadronically-decaying \(W's\) \((W jets)\) from QCD-jets using jet substructure. Previous methods, such as the filtering/mass-drop method, can give a factor of \(\sim ...