The Validity of the Weizsacker-Williams Approximation and the Analysis of Beam Dump Experiments: Production of a New Scalar Boson

Abstract

Beam dump experiments have been used to search for new particles with null results interpreted in terms of limits on masses $m_{\varphi }$ and coupling constants $\epsilon$. However these limits have been obtained by using approximations [including the Weizsäcker-Williams (WW) approximation] or Monte-Carlo simulations. We display methods, using a new scalar boson as an example, to obtain the cross section and the resulting particle production numbers without using approximations or Monte-Carlo simulations. We show that the approximations cannot be used to obtain accurate values of cross sections. The corresponding exclusion plots differ by substantial amounts when seen on a linear scale. In the event of a discovery, we generate pseudodata (assuming given values of $m_{\varphi }$ and $\epsilon$) in the currently allowed regions of parameter space. The use of approximations to analyze the pseudodata for the future experiments is shown to lead to considerable errors in determining the parameters. Furthermore, a new region of parameter space can be explored without using one of the common approximations, $m_{\varphi }\gg m_e$. Our method can be used as a consistency check for Monte-Carlo simulations.

21 pages, 8 figures

References in corpus (7)

• Secluded U(1) below the weak scale
• New Fixed-Target Experiments to Search for Dark Gauge Forces
• New determination of the fine structure constant and test of the quantum electrodynamics
• New Limits on Hidden Photons from Past Electron Beam Dumps
• Muonic hydrogen and MeV forces
• Testing GeV-Scale Dark Matter with Fixed-Target Missing Momentum Experiments
• Probing New Physics with Underground Accelerators and Radioactive Sources

Cited by in corpus (19)

• Light Dark Matter: Models and Constraints
• Dark Sector Production via Proton Bremsstrahlung
• Lepton-Flavor-Violating ALPs at the Electron-Ion Collider: A Golden Opportunity
• Chiral $Z^{\prime }$ in FASER, FASER2, DUNE, and ILC beam dump experiments
• Self-consistent extraction of spectroscopic bounds on light new physics
• A Custodial Symmetry for Muon g-2
• New physics searches at the ILC positron and electron beam dumps
• Lepton-Flavor-Violating ALP Signals with TeV-Scale Muon Beams
• Investigation of the concurrent effects of ALP-photon and ALP-electron couplings in Collider and Beam Dump Searches
• Searching for Muonphilic Dark Sectors with Proton Beams
• New Searches for Muonphilic Particles at Proton Beam Dump Spectrometers
• Probing hidden spin-2 mediator of dark matter with NA64e, LDMX, NA64$\mu$ and M${}^3$
• Gamma Factory Searches for Extremely Weakly-Interacting Particles
• Leptophilic Gauge Bosons at Lepton Beam Dump Experiments
• Resonant probing spin-0 and spin-2 dark matter mediators with fixed target experiments
• Electron Beam Dump Constraints on Light Bosons with Lepton Flavor Violating Couplings
• Muon Beam Dump Experiments probe five-dimensional nature of $U(1{)}_{L_{\mu }-L_{\tau }}$
• Searching for exotic scalars at fusion reactors
• Probing Hidden Sectors with a muon beam: Total and differential cross-sections for vector boson production in muon bremsstrahlung