Now showing items 1-20 of 40

    • Annihilation Decays of Bound States at the LHC 

      Kats, Yevgeny; Schwartz, Matthew D (Springer Verlag, 2010)
      At the Large Hadron Collider, heavy particles may be produced in pairs close to their kinematic threshold. If these particles have strong enough attractive interactions they may form bound states. Consequently, the bound ...
    • Consistent use of effective potentials 

      Andreassen, Anders Johan; Frost, William Thomas; Schwartz, Matthew D (American Physical Society (APS), 2015)
      It is well known that effective potentials can be gauge dependent while their values at extrema should be gauge invariant. Unfortunately, establishing this invariance in perturbation theory is not straightforward, since ...
    • Consistent Use of the Standard Model Effective Potential 

      Andreassen, Anders Johan; Frost, William Thomas; Schwartz, Matthew D (American Physical Society (APS), 2014)
      The stability of the Standard Model is determined by the true minimum of the effective Higgs potential. We show that the potential at its minimum when computed by the traditional method is strongly dependent on the gauge ...
    • Constraining Light Colored Particles with Event Shapes 

      Kaplan, David; Schwartz, Matthew D (American Physical Society, 2008)
      Using recently developed techniques for computing event shapes with Soft-Collinear Effective Theory, LEP event shape data is used to derive strong model-independent bounds on new colored particles. In the effective field ...
    • Deciphering Top Flavor Violation at the LHC with B Factories 

      Fox, Patrick; Ligeti, Zoltan; Papucci, Michele; Perez, Gilad; Schwartz, Matthew D (American Physical Society, 2008)
      The LHC will have unprecedented sensitivity to flavor-changing neutral current (FCNC) top quark decays, whose observation would be a clear sign of physics beyond the standard model. Although many details of top flavor ...
    • Direct Photon Production With Effective Field Theory 

      Becher, Thomas; Schwartz, Matthew D (Springer Verlag, 2010)
      The production of hard photons in hadronic collisions is studied using Soft-Collinear Effective Theory (SCET). This is the first application of SCET to a physical, observable cross section involving energetic partons in ...
    • Effective field theory for massive gravitons and gravity in theory space 

      Arkani-Hamed, Nima; Georgi, Howard; Schwartz, Matthew D (Elsevier BV, 2003)
      We introduce a technique for restoring general coordinate invariance into theories where it is explicitly broken. This is the analog for gravity of the Callan-Coleman-WessZumino formalism for gauge theories. We use this ...
    • Factorization for groomed jet substructure beyond the next-to-leading logarithm 

      Frye, Christopher Robert; Larkoski, Andrew J.; Schwartz, Matthew D; Yan, Kai (Springer Nature, 2016)
      Jet grooming algorithms are widely used in experimental analyses at hadron colliders to remove contaminating radiation from within jets. While the algorithms perform a great service to the experiments, their intricate ...
    • Hard-soft-collinear factorization to all orders 

      Feige, Ilya Eric Alexander; Schwartz, Matthew D (American Physical Society (APS), 2014)
      We provide a precise statement of hard-soft-collinear factorization of scattering amplitudes and prove it to all orders in perturbation theory. Factorization is formulated as the equality at leading power of scattering ...
    • Jet Charge at the LHC 

      Krohn, David; Schwartz, Matthew D; Lin, Tongyan; Waalewijn, Wouter J. (American Physical Society (APS), 2013)
      Knowing the charge of the parton initiating a light-quark jet could be extremely useful both for testing aspects of the standard model and for characterizing potential beyond-the-standard-model signals. We show that despite ...
    • Jet cleansing: Separating data from secondary collision induced radiation at high luminosity 

      Krohn, David; Schwartz, Matthew D; Low, Matthew; Wang, Lian-Tao (American Physical Society (APS), 2014)
      One of the greatest impediments to extracting useful information from high luminosity hadroncollider data is radiation from secondary collisions (i.e. pileup) which can overlap with that of the primary interaction. In this ...
    • Jet mass with a jet veto at two loops and the universality of nonglobal structure 

      Kelley, Randall; Schwartz, Matthew D; Schabinger, Robert M.; Zhu, Hua Xing (American Physical Society (APS), 2012)
      We investigate the exclusive jet mass distribution in e+e− events, defined with a veto on the out-of-jet radiation, at two-loop order. In particular, we calculate the two-loop soft function, which is required to describe ...
    • Jet Physics at High Energy Colliders 

      Chien, Yang-Ting (2013-10-17)
      The future of new physics searches at the LHC will be to look for hadronic signals with jets. In order to distinguish a hadronic signal from its background, it is important to develop advanced collider physics techniques ...
    • Jet physics from static charges in AdS space 

      Chien, Yang-Ting; Schwartz, Matthew D; Simmons-Duffin, David; Stewart, Iain W. (American Physical Society (APS), 2012)
      Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, ...
    • Jet sampling: improving event reconstruction through multiple interpretations 

      Kahawala, Dilani; Krohn, David; Schwartz, Matthew D (Springer Nature, 2013)
      The classification of events involving jets as signal-like or background-like can depend strongly on the jet algorithm used and its parameters. This is partly due to the fact that standard jet algorithms yield a single ...
    • Multivariate Discrimination and the Higgs + W/Z search 

      Black, Kevin; Gallicchio, Jason; Huth, John; Kagan, Michael Aaron; Schwartz, Matthew D; Tweedie, Brock (Springer Verlag, 2011)
      A systematic method for optimizing multivariate discriminants is developed and applied to the important example of a light Higgs boson search at the Tevatron and the LHC. The Significance Improvement Characteristic (SIC), ...
    • Nondeterministic Approach to Tree-Based Jet Substructure 

      Ellis, Stephen D.; Hornig, Andrew; Roy, Tuhin S.; Krohn, David; Schwartz, Matthew D (American Physical Society (APS), 2012)
      Jet substructure is typically studied using clustering algorithms, such as kT , which arrange the jets’ constituents into trees. Instead of considering a single tree per jet, we propose that multiple trees should be ...
    • Nonglobal logarithms at three loops, four loops, five loops, and beyond 

      Schwartz, Matthew D; Zhu, Hua Xing (American Physical Society (APS), 2014)
      We calculate the coefficients of the leading non-global logarithms for the hemispheremass distribution analytically at 3, 4, and 5 loops at large Nc. We confirm that the integrand derived with the strong-energy-ordering ...
    • An on-shell approach to factorization 

      Feige, Ilya Eric Alexander; Schwartz, Matthew D (American Physical Society (APS), 2013)
      Factorization is possible due to the universal behavior of Yang-Mills theories in soft and collinear limits. Here, we take a small step towards a more transparent understanding of these limits by proving a form of perturbative ...
    • One-Loop Matching and Next-to-Next-to-Leading Log Resummation for all Partonic 2→2 Processes in QCD 

      Kelley, Randall; Schwartz, Matthew D (American Physical Society, 2011)
      The Wilson coefficients for all 4-parton operators which arise in matching QCD to soft-collinear effective theory (SCET) are computed at 1-loop. Any dijet observable calculated in SCET beyond leading order will require ...