Searches for dark photons provide serendipitous discovery potential for other types of vector particles. We develop a framework for recasting dark photon searches to obtain constraints on more general theories, which includes a data-driven method for determining hadronic decay rates. We demonstrate our approach by deriving constraints on a vector that couples to the B-L current, a leptophobic B boson that couples directly to baryon number and to leptons via B-γ kinetic mixing, and on a vector that mediates a protophobic force. Our approach can easily be generalized to any massive gauge boson with vector couplings to the Standard Model fermions, and software to perform any such recasting is provided at https://gitlab.com/philten/darkcast.

International audienceThis document outlines a set of simplified models for dark matter and its interactions with Standard Model particles. It is intended to summarize the main characteristics that these simplified models have when applied to dark matter searches at the LHC, and to provide a number of useful expressions for reference. The list of models includes both s-channel and t-channel scenarios. For s-channel, spin-0 and spin-1 mediation is discussed, and also realizations where the Higgs particle provides a portal between the dark and visible sectors. The guiding principles underpinning the proposed simplified models are spelled out, and some suggestions for implementation are presented

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We propose an inclusive search for dark photons A 0 at the LHCb experiment based on both prompt and displaced dimuon resonances. Because the couplings of the dark photon are inherited from the photon via kinetic mixing, the dark photon A 0 → μ þ μ − rate can be directly inferred from the off-shell photon γ Ã → μ þ μ − rate, making this a fully data-driven search. For run 3 of the LHC, we estimate that LHCb will have sensitivity to large regions of the unexplored dark-photon parameter space, especially in the 210-520 MeV and 10-40 GeV mass ranges. This search leverages the excellent invariant-mass and vertex resolution of LHCb, along with its unique particle-identification and real-time data-analysis capabilities. DOI: 10.1103/PhysRevLett.116.251803 Dark matter-firmly established through its interactions with gravity-remains an enigma. Though there are increasingly stringent constraints on direct couplings between visible matter and dark matter, little is known about the dynamics within the dark sector itself. An intriguing possibility is that dark matter might interact via a new dark force, felt only feebly by standard model (SM) particles. This has motivated a worldwide effort to search for dark forces and other portals between the visible and dark sectors (see Ref.[1] for a review).A particularly compelling dark-force scenario is that of a dark photon A 0 which has small SM couplings via kinetic mixing with the ordinary photon through the operator ðϵ=2ÞF 0 μν F μν [2][3][4][5][6][7]. Previous beam dump [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], fixed target [22][23][24], collider [25][26][27], and rare meson decay [28][29][30][31][32][33][34][35][36][37] experiments have already played a crucial role in constraining the dark photon mass m A 0 and kinetic-mixing strength ϵ 2 . Large regions of the m A 0 − ϵ 2 plane, however, are still unexplored (see Fig. 1). Looking to the future, a wide variety of innovative experiments have been proposed to further probe the dark photon parameter space [38][39][40][41][42][43][44][45][46][47][48], though new ideas are needed to test m A 0 > 2m μ and ϵ 2 ∈ ½10 −7 ; 10 −11 .In this Letter, we propose a search for dark photons via the decayat the LHCb experiment during LHC run 3 (scheduled for 2021-2023). The potential of LHCb to discover dark photons was recently emphasized in Ref.[48], which exploits the exclusive charm decay modeHere, we consider an inclusive approach where the production mode of A 0 need not be specified. An important feature of this search is that it can be made fully data driven, since the A 0 signal rate can be inferred from measurements of the SM prompt μ þ μ − spectrum. The excellent invariant-mass and vertex resolution of the LHCb detector, along with its unique particle-identification and real-time data-analysis capabilities [50,51], make it highly sensitive to A 0 → μ þ μ − . We derive the LHCb sensitivity for both prompt and displaced A 0 decays, and show that LHCb can probe otherwise inaccessible regions of the m A 0 − ϵ 2 plane...

Utilizing the Fermi measurement of the gamma-ray spectrum toward the Inner Galaxy, we derive some of the strongest constraints to date on the dark matter (DM) lifetime in the mass range from hundreds of MeV to above an EeV. Our profile-likelihood based analysis relies on 413 weeks of Fermi Pass 8 data from 200 MeV to 2 TeV, along with up-to-date models for diffuse gamma-ray emission within the Milky Way. We model Galactic and extragalactic DM decay and include contributions to the DM-induced gamma-ray flux resulting from both primary emission and inverse-Compton scattering of primary electrons and positrons. For the extragalactic flux, we also calculate the spectrum associated with cascades of high-energy gamma-rays scattering off of the cosmic background radiation. We argue that a decaying DM interpretation for the 10 TeV-1 PeV neutrino flux observed by IceCube is disfavored by our constraints. Our results also challenge a decaying DM explanation of the AMS-02 positron flux. We interpret the results in terms of individual final states and in the context of simplified scenarios such as a hidden-sector glueball model.