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Das ist der HAMMER: consistent new physics interpretations of semileptonic decays

Bernlochner, Florian U. and Duell, Stephan and Ligeti, Zoltan and Papucci, Michele and Robinson, Dean J. (2020) Das ist der HAMMER: consistent new physics interpretations of semileptonic decays. European Physical Journal. C, Particles and Fields, 80 (9). Art. No. 883. ISSN 1434-6044. doi:10.1140/epjc/s10052-020-8304-0.

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Precise measurements of b → cτν̄ decays require large resource-intensive Monte Carlo (MC) samples, which incorporate detailed simulations of detector responses and physics backgrounds. Extracted parameters may be highly sensitive to the underlying theoretical models used in the MC generation. Because new physics (NP) can alter decay distributions and acceptances, the standard practice of fitting NP Wilson coefficients to SM-based measurements of the R(D(∗)) ratios can be biased. The newly developed Hammer software tool enables efficient reweighting of MC samples to arbitrary NP scenarios or to any hadronic matrix elements. We demonstrate how Hammer allows avoidance of biases through self-consistent fits directly to the NP Wilson coefficients. We also present example analyses that demonstrate the sizeable biases that can otherwise occur from naive NP interpretations of SM-based measurements. The Hammer library is presently interfaced with several existing experimental analysis frameworks and we provide an overview of its structure.

Item Type:Article
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URLURL TypeDescription Paper
Ligeti, Zoltan0000-0002-4830-5773
Papucci, Michele0000-0003-0810-0017
Additional Information:© 2020 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit Received: 22 February 2020 / Accepted: 30 July 2020. Funded by SCOAP3. Hammer has been developed with the active participation and testing by many colleagues. We especially thank from LHCb Julián García Pardiñas, Lucia Grillo, Donal Hill, Simone Meloni, Adam Morris, Patrick Owen, and Luke Scantlebury-Smead, for their extensive feedback, discussions, questions, and beta testing during development. We similarly thank from Belle II Kilian Lieret, Thomas Lueck, Felix Metzner, Markus Prim, and Maximilian Welsch. We thank David Shih for discussions and comments on the manuscript. Thanks are also due to all interested users on Belle, Belle II, BaBar, LHCb, and CMS, for many helpful discussions, questions, testing, and feedback. FB was supported by the DFG Emmy-Noether Grant No. BE 6075/1-1. SD was supported by the German Ministry of Research and Science (BMBF). ZL, MP and DR were supported in part by the Office of High Energy Physics of the U.S. Department of Energy under contract DE-AC02-05CH11231. We thank the Aspen Center of Physics, supported by the NSF grant PHY-1607611, where parts of this work were completed. This work also used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231. FB thanks Kim Scott, Bob Michaud and Julie Michaud-B for their hospitality, many good discussions and in general a great time in Houston, where part of this paper was written. Data Availability Statement: This manuscript has no associated data or the data will not be deposited. [Authors’ comment: “Data is available upon request” (there is no real measured data discussed in the manuscript, but we are happy to share the toy data / scripts)].
Funding AgencyGrant Number
Deutsche Forschungsgemeinschaft (DFG)BE 6075/1-1
Bundesministerium für Bildung und Forschung (BMBF)UNSPECIFIED
Department of Energy (DOE)DE-AC02-05CH11231
Issue or Number:9
Record Number:CaltechAUTHORS:20200925-104734634
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Official Citation:Bernlochner, F.U., Duell, S., Ligeti, Z. et al. Das ist der HAMMER: consistent new physics interpretations of semileptonic decays. Eur. Phys. J. C 80, 883 (2020).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:105553
Deposited By: George Porter
Deposited On:25 Sep 2020 19:48
Last Modified:16 Nov 2021 18:44

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