P. F. Harrison's research while affiliated with The University of Warwick and other places

... The suppression depends on the value of n chosen; the larger n is, the faster the suppression. The case of n ¼ 2 corresponds to a dipole form factor, as often adopted for the nucleon form factor. Limits from a recent ATLAS search can be applied to this form factor for the htt vertex [55]. In our study we use Q ¼ p h T since the transverse momentum of the Higgs characterizes the momentum exchange. ...

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Higgs to b b ¯ from vector boson fusion for high-scale physics

... A very easy solution to this conundrum consists in selecting species enriched samples, in which the modification of the relative species abundance plays little or close to no role. There are several options to get quark enriched samples, such as using boson-jet events [11], heavy-flavour tagged jets [12], or performing rapidity scans for a fixed jet p T [7]. The strategy is clear: if one has a very high quark-fraction, and narrowing is still observed, it is due to the medium resolving the jet substructure fluctuations. ...

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Jet modifications and medium response - Theoretical overview

... This scenario also has a strong appeal from a phenomenological perspective: provided some portal interactions connecting dark QCD and the SM exist, "dark shower" (DS) signals can be expected [1,5,6]. These pose fascinating new challenges to the LHC program and have received increasing attention lately, both from the theoretical side [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] and in actual experimental searches [24][25][26][27][28][29]. ...

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Dark showers from Z-dark Z′ mixing

... In contrast to diboson productions, triboson processes are generally quite rare if the leptonic decay channels are considered (the hadronic final states would have huge QCD backgrounds at hadron colliders). Recently, ATLAS and CMS observed some productions of three gauge bosons for the first time from proton-proton collisions with an unprecedented integrated luminosity, such as the productions of three massive gauge bosons [2][3][4][5], one massive plus two massless photons [6][7][8], and two massive plus one massless photon [9,10]. On the other hand, the SM Lagrangian is expanded to include high dimensional operators to parameterize BSM effects in the SM effective field theory (SMEFT) [11][12][13], which provides a convenient way to understand correlations between various experimental results and has been widely used in both experimental and theoretical studies. ...

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Gluon–gluon fusion contribution to the productions of three gauge bosons at the LHC

... The diphoton decay (h → γγ) was one of the channels in which the Higgs was first observed [1,2], while gluon fusion (gg → h) is the most important production mechanism for the Higgs at hadron colliders. Furthermore, the rarer h → γZ decay has recently been observed by the ATLAS and CMS collaborations [3,4]. All of these processes occur at loop level in the Standard Model (SM) and they are promising directions to look for beyond the Standard Model (BSM) physics. ...

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A log story short: running contributions to radiative Higgs decays in the SMEFT

... From the experimental point of view, the H → γ γ was one of the golden decay channels for the Higgs boson discovery. The latest ATLAS and CMS measurements of the Higgs boson mass in this channel are presented in [72,73] and the corresponding cross-section can be found in [74,75]. On the other hand, a recent combined analysis of ATLAS and CMS found evidence for H → γ Z decay [76], which agrees with the SM theoretical expectation within 1.9 standard deviations. ...

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Tripartite entanglement and Bell non-locality in loop-induced Higgs boson decays

... Non-SM terms are referred to as the anomalous contributions. EFT is used in the analyses of experimental data to set the limits on the Wilson coefficients [8,9,10,11]. Often for this purpose, only the signal process is decomposed according to equation (9), whereas background processes are assumed to have the SM term only. ...

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Composite Effective Field Theory Signal from Anomalous QuarticGauge Couplings forZZ(→ℓℓνν)jjandZγ(→ννγ)jjProductions

... Polarisation measurements provide a quite useful handle to obtain information about heavy particles and investigate their properties, in the search for new physics beyond the standard model (SM). The polarisation of the top quarks has been measured by the ATLAS and CMS Collaborations in pair [1,2] and single production [3,4]. The polarisation of W bosons produced in top decays has also been measured [5][6][7][8], as well as the (joint) polarisation of the weak bosons in W Z production [9]. ...

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Crafting polarisations for top, $W$ and $Z

... refs. [1][2][3][4][5][6][7][8] for recent experimental results. They provide a way to re-interpret Standard Model (SM) measurements which exploits their full kinematic range and can guide combinations of different channels. ...

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Going beyond Top EFT

... We do not show monojet and dijet signatures of lower masses [83] as they are weaker than the bounds we FIG. 2. Axion coupling to gluons for m a < 2m χ . Left: constraints on the coupling: robust terrestrial bounds [52][53][54] (pink), beam dumps [55][56][57][58][59][60][61][62][63] (brown), meson decays [53,[64][65][66][67][68][69][70][71][72] (turquoise), colliders [73][74][75][76][77][78][79][80][81][82][83][84][85][86][87] (orange), BBN [88,89] (purple), astrophysical [90] (dark blue), and new colored particles [91][92][93][94][95] (gray). EFT constraints are indicated by gray shaded regions. ...

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Dark matter through the axion-gluon portal