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A bstract We look for oscillating signals in the primordial bispectrum from new physics heavy particles which are visibly large for next generation large scale structures (LSS) survey. We show that in ordinary inflation scenarios where a slow-rolling inflaton generates density fluctuations and with no breaking of scale invariance or spacetime symmetry, there exist no naturally large signals unless the rolling inflaton generates a parity-odd chemical potential for the heavy particles. We estimate the accessibility of this signal through observations. While current CMB data are already sensitive in the most optimistic scenario, future probes, including LSS survey and 21 cm observation, can cover interesting regions of the model space.

A bstract We study the production of massive gauge bosons during inflation from the axion-type coupling to the inflaton and the corresponding oscillatory features in the primordial non-Gaussianity. In a window in which both the gauge boson mass and the chemical potential are large, the signal is potentially reachable by near-future large scale structure probes. This scenario covers a new region in oscillation frequency which is not populated by previously known cosmological collider models. We also demonstrate how to properly include the exponential factor and discuss the subtleties in obtaining power dependence of the gauge boson mass in the signal estimate.

A bstract The QCD axion’s coupling to photons is often assumed to lie in a narrow band as a function of the axion mass. We demonstrate that several simple mechanisms, in addition to the photophilic clockwork axion already in the literature, can significantly extend the allowed range of couplings. Some mechanisms we present generalize the KNP alignment scenario, widely studied as a model of inflation, to the phenomenology of a QCD axion. In particular we present KSVZ-like realizations of two-axion KNP alignment and of the clockwork mechanism. Such a “confinement tower” realization of clockwork may prove useful in a variety of model-building contexts. We also show that kinetic mixing of the QCD axion with a lighter axion-like particle can dramatically alter the QCD axion’s coupling to photons, differing from the other models we present by allowing non-quantized couplings. The simple models that we present fully cover the range of axion-photon couplings that could be probed by experiments. They motivate growing axion detection efforts over a wide space of masses and couplings.

A bstract The dispersion relation of an elastic 4-point amplitude in the forward direction leads to a sum rule that connects the low energy amplitude to the high energy observables. We perform a classification of these sum rules based on massless helicity amplitudes. With this classification, we are able to systematically write down the sum rules for the dimension-6 operators of the Standard Model Effective Field Theory (SMEFT), some of which are absent in previous literatures. These sum rules offer distinct insights on the relations between the operator coefficients in the EFT and the properties of the full theory that generates them. Their applicability goes beyond tree level, and in some cases can be used as a practical method of computing the one loop contributions to low energy observables. They also provide an interesting perspective for understanding the custodial symmetries of the SM Higgs and fermion sectors.

A bstract In recent years the search for dark matter has intensified with competitive bounds coming from collider searches, direct detection, and indirect detection. Collider searches at the Large Hadron Collider (LHC) lack the necessary center-of-mass energy to probe TeV-scale dark matter. It is TeV-scale dark matter, however, that remains viable for many models of supersymmetry. In this paper, we study the reach of a 100 TeV proton-proton collider for neutralino dark matter and compare to 14 TeV LHC projections. We employ a supersymmetric simplified model approach and present reach estimates from monojet searches, soft lepton searches, and disappearing track searches. The searches are applied to pure neutralino spectra, compressed neutralino spectra, and coannihilating spectra. We find a factor of 4-5 improvement in mass reach in going from 14 TeV to 100 TeV. More specifically, we find that given a 1% systematic uncertainty, a 100 TeV collider could exclude winos up to 1.4 TeV and higgsinos up to 850 GeV in the monojet channel. Coannihilation scenarios with gluinos can be excluded with neutralino masses of 6.2 TeV, with stops at 2.8 TeV, and with squarks at 4.0 TeV. Using a soft lepton search, compressed spectra with a chargino-neutralino splitting of Δ m = 20 − 30 GeV can exclude neutralinos at ~1 TeV. Given a sufficiently long chargino lifetime, the disappearing track search is very effective and we extrapolate current experimental bounds to estimate that a ~2TeVwinocouldbediscoveredanda ~3TeVwinocouldbeexcluded.

Initial state radiation, multiple interactions, and event pileup can contaminate jets and degrade event reconstruction. Here we introduce a procedure, jet trimming, designed to mitigate these sources of contamination in jets initiated by light partons. This procedure is complimentary to existing methods developed for boosted heavy particles. We find that jet trimming can achieve significant improvements in event reconstruction, especially at high energy/luminosity hadron colliders like the LHC.

A bstract Non-invertible global symmetry often predicts degeneracy in axion potentials and carries important information about the global form of the gauge group. When these symmetries are spontaneously broken they can lead to the formation of stable axion domain wall networks which support topological degrees of freedom on their worldvolume. Such non-invertible symmetries can be broken by embedding into appropriate larger UV gauge groups where small instanton contributions lift the vacuum degeneracy, and provide a possible solution to the domain wall problem. We explain these ideas in simple illustrative examples and then apply them to the Standard Model, whose gauge algebra and matter content are consistent with several possible global structures. Each possible global structure leads to different selection rules on the axion couplings, and various UV completions of the Standard Model lead to more specific relations. As a proof of principle, we also present an example of a UV embedding of the Standard Model which can solve the axion domain wall problem. The formation and annihilation of the long-lived axion domain walls can lead to observables, such as gravitational wave signals. Observing such signals, in combination with the axion coupling measurements, can provide valuable insight into the global structure of the Standard Model, as well as its UV completion.

Among the numerous proposals to explain the nature of dark matter, there is the weakly interacting massive particle (WIMP) scenario, which is based on a simple assumption that dark matter was in thermal equilibrium in the early hot Universe, and its particles have mass and interactions not too different from the massive particles in the standard model. In this Progress Article we overview the inference of WIMP production at high-energy colliders, with a particular focus on searches at the Large Hadron Collider. Beyond the standard model, the weakly interacting massive particle (WIMP) hypothesis for dark matter is one of the most compelling, and the one being tested at the Large Hadron Collider.

A bstract We initiate a systematic study of precision calculation of the inflation correlators at the 1-loop level, starting in this paper with bosonic 1-loop bispectrum with chemical-potential enhancement. Such 1-loop processes could lead to important cosmological collider observables but are notoriously difficult to compute due to the lack of symmetries. We attack the problem from a direct numerical approach based on the real-time Schwinger-Keldysh formalism and show full numerical results for arbitrary kinematics containing both the oscillatory “signals” and the “backgrounds”. Our results show that, while the non-oscillatory part can be one to two orders of magnitude larger, the oscillatory signal can be separated out by applying appropriate high-pass filters. We have also compared the result with analytic estimates typically adopted in the literature. While the amplitude is comparable, there is a non-negligible deviation in the frequency of the oscillatory part away from the extreme squeezed limit.

A bstract The search for long-lived particles (LLP) is an exciting physics opportunity in the upcoming runs of the Large Hadron Collider. In this paper, we focus on a new search strategy of using the High Granularity Calorimeter (HGCAL), part of the upgrade of the CMS detector, in such searches. In particular, we demonstrate that the high granularity of the calorimeter allows us to see “shower tracks” in the calorimeter, and can play a crucial role in identifying the signal and suppressing the background. We study the potential reach of the HGCAL using a signal model in which the Standard Model Higgs boson decays into a pair of LLPs, h → XX . After carefully estimating the Standard Model QCD and the misreconstructed fake-track backgrounds, we give the projected reach for both an existing vector boson fusion trigger and a novel displaced-track-based trigger. Our results show that the best reach for the Higgs decay branching ratio, BR( h → XX ), in the vector boson fusion channel is about O (10 − 4 ) with lifetime cτ X ∼ 0 . 1–1 meters, while for the gluon gluon fusion channel it is about O (10 − 5 –10 − 6 ) for similar lifetimes. For longer lifetime cτ X ∼ 10 3 meters, our search could probe BR( h → XX ) down to a few × 10 − 4 (10 − 2 ) in the gluon gluon fusion (vector boson fusion) channels, respectively. In comparison with these previous searches, our new search shows enhanced sensitivity in complementary regions of the LLP parameter space. We also comment on many improvements can be implemented to further improve our proposed search.