Taylor Murphy

Biography

I completed my Ph.D. in theoretical particle physics at The Ohio State University. I recently completed a year of postdoctoral research at the Theoretical High-Energy Physics Laboratory (LPTHE) in Paris, France. I have seven years of physics education experience as a graduate student and lecturer.

Education

• Ph.D. Physics, The Ohio State University (2022)
• M.S. Physics, The Ohio State University (2019)
• B.S. Physics, University of Oklahoma (2016)
• B.A. Mathematics, University of Oklahoma (2016)

Research Interests

My research is in elementary particle physics, the field of physics concerned with cataloging and understanding the fundamental constituents of the Universe. According to our current understanding, elementary particles include familiar species like the electron and photon, but also the components (quarks and gluons) of other well known subatomic particles like the proton. This field of physics reached maturity during the twentieth century, culminating in the celebrated Standard Model (SM) of particle physics, which provides an excellent quantitative description of the visible matter in the Universe.

But the SM suffers from multiple shortcomings: it does not incorporate gravity, which is instead described very well by general relativity; it does not necessarily include neutrino masses, which are an experimental reality; it does not accommodate the probable existence of large quantities of non-luminous ("dark") matter in the Universe; and there is a constellation of small discrepancies between SM predictions and current experimental data. These problems motivate particle physicists to search for physics beyond the Standard Model (BSM): this is the holy grail of the field.

Particle physics is a large collaborative effort among theoretical physicists, who develop models including novel particles and interactions and perform calculations and simulations in order to make testable predictions; and experimental physicists, who design and operate colliders, detectors, telescopes, etc. and analyze the data they collect. My research is in theory, and often particularly in phenomenology, which is the branch of theoretical physics aimed at making predictions relevant for present-day or near-future experiments and (re)interpreting current experimental results in the search for new physics. This focus gives me the opportunity to regularly communicate with experimental physicists. My day-to-day work involves model building, which requires mathematical tools like group theory and quantum field theory; numerical calculations, which rely on a variety of computer programs but can often be done on an individual machine; and simulations and analysis, which often require large computing resources available only on computer clusters.

My research program is fairly broad; I have collaborated with American and international researchers with a wide variety of interests. This breadth is motivated both by an ever-changing experimental landscape and by my belief that theorists should search for BSM physics wherever it could be hiding. I have studied an array of supersymmetric models ranging from the Minimal Supersymmetric Standard Model to brand-new models with a softly broken U(1) R symmetry; I have cataloged the low-dimensional effective interactions of color-sextet particles; I have built toy models to explain a possible heavier W boson as suggested by the CDF Collaboration; and I helped develop the frameworks of frustrated dark matter and the Light Exotics Effective Field Theory (LEX-EFT). A recurring theme in my work is building models that explain experimental anomalies at the Large Hadron Collider (LHC). I am moreover a contributing member of the LHC Dark Matter Working Group. My current projects include and extend these interests: I invite any interested party to contact me to discuss research.

Courses Taught

• PHY 103: Concepts in Physics Laboratory
• PHY 181: General Physics I

Publications

Preprints and publications from the last twelve months:

• Monojets from compressed weak frustrated dark matter. B. Fuks, M. D. Goodsell, T. Murphy, arXiv:2409:03014.
• Seeking a coherent explanation of LHC excesses for compressed spectra. D. Agin, B. Fuks, M. D. Goodsell, T. Murphy, arXiv:2404.12423.
• Dark matter with exotic mediators: The diquark portal. L. M. Carpenter, T. Murphy, arXiv:2313.17607.
• Monojets reveal overlapping excesses for light-compressed higgsinos. D. Agin, B. Fuks, M. D. Goodsell, T. Murphy, Phys. Lett. B 853 (2024) 138597.
• Leptonic signatures of color-sextet scalars II: Exploiting unique large-MET signals at the LHC. L. M. Carpenter, K. Schwind, T. Murphy, Phys. Rev. D 109, 075010 (2024).
• Taking aim at the wino-higgsino plane with the LHC. L. M. Carpenter, H. B. Gilmer, T. Murphy, J. Kawamura, Phys. Rev. D 109, 015012 (2024).

Current Projects

1. Searching for a BSM model with a unified explanation of ongoing excesses in the soft-leptons and monojet channels at the LHC
2. Exploring the interplay between monojet and multijet constraints on supersymmetric models with a higgsino-like lightest supersymmetric particle (LSP)
3. Painting a global picture of constraints on simplified supersymmetric models in light of possibly overlapping excesses in the leptonic and b-hadron channels
4. Building out the catalog of low-dimensional effective diboson operators involving one light exotic (LEX) field and identifying the most interesting phenomenology for the LHC or future colliders, including the possible U.S.-based muon collider