In this study, we investigate the $R^2$ corrections to the dissociation of heavy quarkonium in the Gauss-Bonnet gravitational background. We analyze the impact of the Gauss-Bonnet parameter $\lambda_{\rm GB}$ on the spectral function of charmonium and bottomonium and examine the effect of $\lambda_{\rm GB}$ on the dissociation of heavy quarkonium. Our results show that $\lambda_{\rm GB}$ reduces the peak height and increases the peak width of the spectral function, suggesting that $\lambda_{\rm GB}$ enhances the dissociation of heavy quarkonium. We also discuss the variation in the dissociation of heavy quarkonium with the ratio of shear viscosity to entropy density and observe that the dissociation is easier in more perfect plasma. Additionally, we observe that the temperature decreases the peak height and widens the peak, thereby accelerating the dissociation.

China

Zhou-Run Zhu

Manman Sun

Rui Zhou

Jinzhong Han

$\textit{R}$ $^{2}$ corrections to holographic heavy quarkonium dissociation * Rui Zhou supported by the Science and Technology Development Plan Project of Henan Province, China (242102230085), the National Natural Science Foundation of China (12404470), the High Level Talents Research and Startup Foundation Projects for Doctors of Zhoukou Normal University, China (ZKNUC2023017). Manman Sun supported by the National Natural Science Foundation of China (12305076). Zhou-Run Zhu supported by the High Level Talents Research and Startup Foundation Projects for Doctors of Zhoukou Normal University, China (ZKNUC2023018)

Neutral triple gauge couplings (nTGCs) are a manifestation of new physics beyond the Standard Model (SM), as they are absent in the SM and are first generated by dimension-8 operators in the SM effective field theory (SMEFT). We study the UV completion of nTGCs in a renormalizable model with vectorlike heavy fermions. We compute the one-loop heavy fermion contributions to nTGC vertices by matching them to dimension-8 operators in the low energy limit. Such fermion loops contain either heavy fermions only or mixture of heavy fermions with light SM fermions. We find that their contributions can induce dimension-8 nTGC effective operators containing two SM Higgs-doublet fields, which are formulated with a complete set of 7 dimension-8 operators generating off-shell <math><mi>C</mi><mi>P</mi></math>-even nTGCs. We present the results in terms of SMEFT coefficients and in terms of nTGC vertices (form factors) with two on-shell gauge bosons. In the heavy-light mixing case there appear terms that cannot be accommodated by conventional parametrizations of form factors due to extra logarithmic corrections. We further discuss the implications for probing such UV dynamics via nTGCs at high-energy colliders.

CERN

United Kingdom

John Ellis

Hong-Jian He

Rui-Qing Xiao

Shi-Ping Zeng

Jiaming Zheng

UV completion of neutral triple gauge couplings

We study probes of neutral triple gauge couplings (nTGCs) via <math><mrow><msup><mrow><mi>Z</mi></mrow><mrow><mo>*</mo></mrow></msup><mi>γ</mi></mrow></math> production with off-shell decays <math><mrow><msup><mrow><mi>Z</mi></mrow><mrow><mo>*</mo></mrow></msup><mo>→</mo><mi>ν</mi><mover><mrow><mi>ν</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math> at the LHC and the projected <math><mi>p</mi><mi>p</mi></math> (100 TeV) colliders, including both <math><mi>C</mi><mi>P</mi></math>-conserving (CPC) and <math><mi>C</mi><mi>P</mi></math>-violating (CPV) couplings. We present the dimension-8 Standard Model effective field theory (SMEFT) operators contributing to nTGCs and derive the correct form factor formulation for the doubly off-shell vertices <math><msup><mi>Z</mi><mo>*</mo></msup><mi>γ</mi><msup><mi>V</mi><mo>*</mo></msup></math> (<math><mrow><mi>V</mi><mo>=</mo><mi>Z</mi></mrow></math>, <math><mrow><mi>γ</mi></mrow></math>) by matching them with the dimension-8 SMEFT operators. We include new contributions enhanced by the large off-shell momentum of <math><msup><mi>Z</mi><mo>*</mo></msup></math>, beyond those of the conventional <math><mi>Z</mi><mi>γ</mi><msup><mi>V</mi><mo>*</mo></msup></math> vertices with on-shell <math><mi>Z</mi><mi>γ</mi></math>. We analyze the sensitivity reaches for probing the <math><mrow><mi>CPC</mi><mo>/</mo><mi>CPV</mi></mrow></math> nTGC form factors and the new physics scales of the dimension-8 nTGC operators at the LHC and future 100 TeV <math><mi>p</mi><mi>p</mi></math> colliders. We compare our new predictions with the existing LHC measurements of CPC nTGCs in the <math><mi>ν</mi><mover><mi>ν</mi><mo>¯</mo></mover><mi>γ</mi></math> channel and demonstrate the importance of our new method.

Probing neutral triple gauge couplings with <math><mrow><msup><mrow><mi>Z</mi></mrow><mrow><mo>*</mo></mrow></msup><mi>γ</mi></mrow></math> (<math><mrow><mi>ν</mi><mover><mrow><mi>ν</mi></mrow><mrow><mo>¯</mo></mrow></mover><mi>γ</mi></mrow></math>) production at hadron colliders

The hMSSM is a special parameterization of the minimal supersymmetric extension of the Standard Model (MSSM) in which the mass of the lightest Higgs boson is automatically set to the LHC measured value, M  h =125 GeV, by adjusting the supersymmetric particle spectrum such that it provides the required amount of radiative corrections to the Higgs boson masses. The latter spectrum was in general assumed to be very heavy, as indicated by the present exclusion limits of the LHC, not to affect the phenomenology of the Higgs sector. In this work, we investigate the impact on the hMSSM by a light gaugino and higgsino sector, that is allowed by the present LHC data. In particular, we discuss the radiative corrections due to charginos and neutralinos to the Higgs boson masses and couplings and show that an hMSSM can still be realized in this context. We first describe how this scenario is implemented in the package SuSpect that generates the MSSM Higgs and supersymmetric spectra. We then analyze the possible impact of Higgs boson decays into these new states, as well as the reverse cascade channels with Higgs bosons in the final states, for the constraints on the MSSM Higgs sector at the LHC. We further explore the cosmological constraints on the hMSSM with a light gaugino-higgsino spectrum. We analyze the relic abundance of the lightest neutralino as a candidate of the dark matter in the Universe and the constraints on its mass and couplings by the present and future astroparticle physics experiments.

Italy

Giorgio Arcadi

Estonia

Spain

Abdelhak Djouadi

France

Jean-Loic Kneur

The hMSSM with a light gaugino/higgsino sector: implications for collider and astroparticle physics

We study probes of neutral triple gauge couplings (nTGCs) at the LHC and the proposed 100 TeV <math><mi>p</mi><mi>p</mi></math> colliders, and compare their sensitivity reaches with those of proposed <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> colliders. The nTGCs provide a unique window to the new physics beyond the Standard Model (SM) because they can arise from SM effective field theory operators that respect the full electroweak gauge group <math><mrow><mi>SU</mi><mo>(</mo><mn>2</mn><msub><mrow><mo>)</mo></mrow><mrow><mi>L</mi></mrow></msub><mo>⊗</mo><msub><mrow><mi>U</mi><mo>(</mo><mn>1</mn><mo>)</mo></mrow><mrow><mi>Y</mi></mrow></msub></mrow></math> of the SM only at the level of dimension-8 or higher. We derive the neutral triple gauge vertices (nTGVs) generated by these dimension-8 operators in the broken phase and map them onto a newly generalized form factor formulation, which takes into account only the residual <math><mrow><mi>U</mi><mo>(</mo><mn>1</mn><msub><mrow><mo>)</mo></mrow><mrow><mi>em</mi></mrow></msub></mrow></math> gauge symmetry. Using this mapping, we derive new nontrivial relations between the form factors that guarantee a truly consistent form factor formulation of the nTGVs and remove large unphysical energy-dependent terms. We then analyze the sensitivity reaches of the LHC and future 100 TeV hadron colliders for probing the nTGCs via both the dimension-8 nTGC operators and the corresponding nTGC form factors in the reaction <math><mrow><mi>p</mi><mi>p</mi><mo>(</mo><mi>q</mi><mover><mrow><mi>q</mi></mrow><mrow><mo>¯</mo></mrow></mover><mo>)</mo><mo>→</mo><mi>Z</mi><mi>γ</mi></mrow></math> with <math><mrow><mi>Z</mi><mo>→</mo><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mo>ℓ</mo></mrow><mrow><mo>−</mo></mrow></msup></mrow></math>, <math><mrow><mi>ν</mi><mover><mrow><mi>ν</mi></mrow><mrow><mo>¯</mo></mrow></mover></mrow></math>. We compare their sensitivities with the existing LHC measurements of nTGCs and with those of the high-energy <math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mo>+</mo></mrow></msup><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> colliders. In general, we find that the prospective LHC sensitivities are comparable to those of an <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> collider with center-of-mass energy <math><mrow><mo>≤</mo><mn>1</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi></mrow></math>, whereas an <math><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></math> collider with center-of-mass energy (3–5) TeV would have greater sensitivities, and a 100 TeV <math><mi>p</mi><mi>p</mi></math> collider could provide the most sensitive probes of the nTGCs.

Probing neutral triple gauge couplings at the LHC and future hadron colliders

We use the spectral lag catalog of 46 short GRBs aggregated by Xiao et al. (Astrophys J Lett 924:L29, 2022), to carry out an independent search for Lorentz invariance violation (LIV). For this purpose, we use a power-law model as a function of energy for the intrinsic astrophysical induced spectral lags. The expansion history of the universe needed for constraining LIV was obtained in a non-parametric method using cosmic chronometers. We use Bayesian model comparison to determine if the aforementioned spectral lags show evidence for LIV as compared to only astrophysically induced lags. We do not find any evidence for LIV, and obtain 95% CL lower limits on the corresponding energy scale to be  $$4 \times 10^{15}$$  <math> <mrow> <mn>4</mn> <mo>×</mo> <msup> <mn>10</mn> <mn>15</mn> </msup> </mrow> </math>   GeV and  $$6.8 \times 10^{9}$$  <math> <mrow> <mn>6.8</mn> <mo>×</mo> <msup> <mn>10</mn> <mn>9</mn> </msup> </mrow> </math>   GeV for the linear and quadratic LIV models respectively. Our results obtained by using the flat  $$\Lambda $$  <math> <mi>Λ</mi> </math>  CDM model for characterizing the cosmic expansion history are consistent with those obtained using chronometers.

India

Shantanu Desai

Rajdeep Agrawal

Germany

Haveesh Singirikonda

Search for Lorentz invariance violation using Bayesian model comparison applied to Xiao et al. GRB spectral lag catalog

We study the quasi-two-body decays 
					 by employing the perturbative QCD (PQCD) factorization approach, where the charmonia 
					 represents 
					 and 
					. The corresponding decay channels are studied by constructing the kaon-pion distribution amplitude (DA) 
					, which comprises important final state interactions between the kaon and pion in the resonant region. Relativistic Breit-Wigner formulas are adopted to parameterize the time-like form factor 
					 appearing in the kaon-pion DAs. The SU(3) flavor symmetry breaking effect resulting from the mass difference between the kaon and pion is taken into account, which makes significant contributions to the longitudinal polarizations. The observed branching ratios and the polarization fractions of 
					 are accommodated by tuning hadronic parameters for the kaon-pion DAs. The PQCD predictions for 
					 modes from the same set of parameters can be tested by precise data obtained in the future from LHCb and Belle II experiments.
				

Ya Li

Zhou Rui

Zhen-Jun Xiao

P-wave contributions to B(s)→ψKπ decays in perturbative QCD approach Supported by the National Natural Science Foundation of China (11947013, 11605060, 11775117, 11547020); Ya Li is also Supported by the Natural Science Foundation of Jiangsu Province (BK20190508) and the Research Start-up Funding of Nanjing Agricultural University; Zhou Rui is Supported in part by the Natural Science Foundation of Hebei Province (A2019209449)

The 
					 triple neutral gauge couplings are absent in the Standard Model (SM) at the tree level. They receive no contributions from dimension-6 effective operators, but can arise from effective operators of dimension-8. We study the scale of new physics associated with such dimension-8 operators that can be probed by measuring the reaction 
					 followed by 
					 decays, at future 
					 colliders including the CEPC, FCC-ee, ILC and CLIC. We demonstrate how angular distributions of the final-state mono-photon and leptons can play a key rôle in suppressing SM backgrounds. We further demonstrate that using electron/positron beam polarizations can significantly improve the signal sensitivities. We find that the dimension-8 new physics scale can be probed up to the multi-TeV region at such lepton colliders.
				

Shao-Feng Ge

Probing the scale of new physics in the ZZγ coupling at e+e− colliders The work of JE was supported in part by United Kingdom STFC Grant ST/P000258/1, in part by the Estonian Research Council via a Mobilitas Pluss grant, and in part by the TDLI distinguished visiting fellow programme. The work of HJH and RQX was supported in part by the National NSF of China (11675086, 11835005). HJH is also supported in part by the CAS Center for Excellence in Particle Physics (CCEPP), by the National Key R&D Program of China ( 2017YFA0402204), by the Shanghai Laboratory for Particle Physics and Cosmology (11DZ2260700), and by the Office of Science and Technology, Shanghai Municipal Government (16DZ2260200)

Searching for new Higgs particle beyond the observed light Higgs boson h 0(125 GeV) will unambiguously point to new physics beyond the standard model. We study the resonant production of a CP-even heavy Higgs state H 0 in the di-Higgs channel, gg → H 0 → h 0 h 0 → WW * WW *, at the LHC Run-2 and the high luminosity LHC (HL-LHC). We analyze two types of the 4W decay modes, one with the same-sign di-leptons (4W → ℓ ± νℓ ± ν4q) and the other with tri-leptons (4W → ℓ ± νℓ ∓ νℓ ± ν2q). We perform a full simulation for the signals and backgrounds, and estimate the discovery potential of the heavy Higgs state at the LHC Run-2 and the HL-LHC, in the context of generic two-Higgs-doublet models (2HDM). We determine the viable parameter space of the 2HDM as allowed by the theoretical constraints and the current experimental limits. We systematically analyze the allowed parameter space of the 2HDM which can be effectively probed by the heavy Higgs searches of the LHC, and further compare this with the viable parameter region under the current theoretical and experimental bounds.

Canada

Jing Ren

United States

Maosen Zhou

Yaquan Fang

Weiming Yao

LHC search of new Higgs boson via resonant di-Higgs production with decays into 4W

New physics beyond the standard model (SM) can be model-independently formulated via dimension-6 effective operators, whose coefficients (cutoffs) characterize the scales of new physics. We study the probe of new physics scales from the electroweak precision observables (EWPO) and the Higgs observables (HO) at the future e + e − Higgs factory (such as CEPC). To optimize constraints of new physics from all available observables, we establish a scheme-independent approach. With this formulation, we treat the SM electroweak parameters and the coefficients of dimension-6 operators on equal footing, which can be fitted simultaneously by the same χ 2 function. As deviations from the SM are generally small, we can expand the new physics parameters up to linear order and perform an analytical χ 2 fit to derive the potential reach of the new physics scales. We find that the HO from both Higgs produnction and decay rates can probe the new physics scales up to 10 TeV (and to 44 TeV for the case of gluon-involved operator O g $$ {\mathcal{O}}_g $$ ), and the new physics scales of Yukawa-type operators can be probed by the precision Higgs coupling measurements up to (13 − 25) TeV. Further including the EWPO can push the limit up to 35 TeV. From this prospect, we demonstrate that the EWPO measured in the early phase of a Higgs factory can be as important as the Higgs observables. These indirect probes of new physics scales at the Higgs factory can mainly cover the energy range to be directly explored by the next generation hadron colliders of pp (50 −100 TeV), such as the SPPC and FCC-hh.

Probing new physics scales from Higgs and electroweak observables at e + e − Higgs factory