Year: 2026
Type: article
Abstract: A bstract In the Type-I two-Higgs Doublet Model (2HDM), the additional scalars may be light (≲ 100 GeV) without conflicting with experimental constraints from LHC searches or from flavour observables. So far, the studies of light scalars at the LHC have been limited to exploring non-standard decays of the Standard Model (SM) Higgs boson or via $$ b\overline{b} $$ b b ¯ associated production followed by leptonic decays of the light scalar. A light scalar in Type-I 2HDM can evade these search strategies due to its potentially tiny coupling to the SM Higgs boson and its suppressed coupling to quarks. In this work, we study the electroweak production of scalar pairs involving the light scalar h , the pseudoscalar A and the charged Higgs boson H ± . The subsequent decays of the heavy scalars into h and an electroweak gauge boson lead to multi- h final states, in which the light scalars are typically boosted owing to the hierarchical scalar spectrum. The decay of the boosted h into $$ b\overline{b} $$ b b ¯ can be reconstructed within a fat-jet containing a pair of b -subjets. We find that tagging such a ‘boosted double- b fat-jet ( J bb )’ signature in association with a SM gauge boson provides an excellent probe of the Type-I 2HDM for hierarchical scalar spectra. Using multiple light mass M h benchmarks, we demonstrate that such analysis can explore a large region of the parameter space, with the 2 σ exclusion reach for the heavy scalars extending up to ~ 560 GeV (~ 370 GeV) at the HL-LHC with 3000 fb −1 (LHC with 300 fb −1 ) luminosity for light scalar masses in the range 30–70 GeV. Furthermore, we show that significant sensitivity and even resonance reconstruction can be achieved within a model-independent framework, highlighting the robustness of this search strategy.
Source: Journal of High Energy Physics
Authors: Partha Konar, Tanmoy Mondal, Chandrima Sen
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Award: G858235257
OpenAlex ID: W7161124434