Stability analysis, dark matter, neutrino and collider
phenomenology of physics beyond the Standard Model
in the context of high-energy high-luminosity colliders
(HE-LHC, HE-HL-LHC, ILC etc.).
30
Scopus Publications
619
Scholar Citations
10
Scholar h-index
13
Scholar i10-index
Scopus Publications
Exploring the dark sector of the inspired FNSM at the LHC Amit Chakraborty, Dilip Kumar Ghosh, Najimuddin Khan, Stefano Moretti Nuclear Physics B, 2026 We establish the possibility of having a pseudo-Nambu-Goldstone boson (pNGB) Dark Matter (DM) candidate in the inspired Froggatt-Nielsen Singlet Model (iFNSM) wherein a direct connection exists between the DM mass and a new flavon symmetry-breaking scale. We find a considerable allowed region of parameter space for the ensuing pseudoscalar DM, which is dependent upon the flavon Vacuum Expectation Value (VEV) and Yukawa couplings, over which it may be possible to explain the fermion mass hierarchy. Finally, we choose a Benchmark Point (BP) and perform detailed collider analyses to probe this DM state in the context of Run 3 at the Large Hadron Collider (LHC). Specifically, in this model, one obtains a large missing transverse energy (/ET) when the DM particle is resonantly produced from the decay of a heavy Higgs field, along with multiple jets from Initial State Radiation (ISR). Thus, the ensuing signature /ET + n jets (n≥1) is an excellent probe of DM in this construct.
Scotogenic model with U(1) symmetry and a scalar dark matter Anjan Kumar Barik, Najimuddin Khan, Santosh Kumar Rai Physical Review D, 2025 We study a scotogenic model augmented with an additional U(1) gauge and a discrete Z2 symmetry. The lightest Z2-odd particle in our model becomes the dark matter (DM) candidate while tiny neutrino masses are realized at one loop. We explore the parameter space of the model for which the DM relic density is satisfied, and the correct low-energy neutrino observables are reproduced. The extended gauge symmetry includes a beyond Standard Model (SM) particle spectrum consisting of vectorlike fermions and scalars. We also highlight possible collider signatures of these particles at the LHC. Published by the American Physical Society 2025
Finding flavons at colliders Gauhar Abbas, Ashutosh Kumar Alok, Neetu Raj Singh Chundawat, Najimuddin Khan, Neelam Singh Physical Review D, 2024 We conduct a comprehensive investigation into the flavor phenomenology and collider signatures of flavon of ZN×ZM flavor symmetries for the soft symmetry-breaking scenario and a new symmetry-conserving mechanism at the high-luminosity LHC, high-energy LHC, and a 100 TeV hadron collider. The flavor physics of quark and leptonic observables places different bounds on the parameter space of flavons of ZN×ZM flavor symmetries. On the collider side, the decay t→ca can be probed by the high-luminosity LHC, high-energy LHC, and a 100 TeV hadron collider for the Z8×Z22 flavor symmetry. The inclusive production signatures can be used to probe the flavon of all the ZN×ZM flavor symmetries for the soft symmetry-breaking scenario for a heavy flavon at a 100 TeV collider. Flavons of all the ZN×ZM flavor symmetries can be probed at high-energy LHC and a 100 TeV collider for a low mass in the case of soft symmetry breaking. The diflavon production is within reach of the high-luminosity LHC, high-energy LHC, and a 100 TeV collider only for a light flavon. The 14 TeV high-luminosity LHC can probe only the Z2×Z5 and Z8×Z22 flavor symmetries for a few specific inclusive signatures. The symmetry-conserving scenario remains beyond the detection capabilities of any collider. Published by the American Physical Society 2024
A model of light pseudoscalar dark matter Shreyashi Chakdar, Dilip Kumar Ghosh, P.Q. Hung, Najimuddin Khan, Dibyendu Nanda Nuclear Physics B, 2024 The EW-νR model was constructed in order to provide a seesaw scenario operating at the Electroweak scale ΛEW∼246 GeV, keeping the same SM gauge structure. In this model, right-handed neutrinos are non-sterile and have masses of the order ΛEW. They can be searched for at the LHC along with heavy mirror quarks and leptons, the lightest of which has large decay lengths. The model also incorporates a rich scalar sector, consistent with various experimental constraints, predicts a ∼125 GeV scalar with the SM Higgs characteristics satisfying the current LHC Higgs boson data. The seesaw mechanism requires the existence of a complex scalar which is singlet under the SM gauge group. The imaginary part of this complex scalar denoted by As0 is proposed to be the sub-MeV dark matter candidate in this manuscript. We find that the sub-MeV scalar can serve as a viable non-thermal feebly interacting massive particle (FIMP)-DM candidate. This As0 can be a naturally light sub-MeV DM candidate due to its nature as a pseudo-Nambu-Goldstone (PNG) boson in the model. We show that the well-studied freeze out mechanism falls short in this particular framework producing DM overabundance. We identify that the freeze in mechanism produces the correct order of relic density for the sub-MeV DM candidate satisfying all applicable constraints. We also discuss the allowed parameter space arising from the current indirect search bounds for this sub-MeV DM.
A 17 MeV pseudoscalar and the LSND, MiniBooNE and ATOMKI anomalies Waleed Abdallah, Raj Gandhi, Tathagata Ghosh, Najimuddin Khan, Samiran Roy, Subhojit Roy Journal of High Energy Physics, 2024 In the absence of any new physics signals at the Large Hadron Collider (LHC), anomalous results at low energy experiments have become the subject of increased attention. We focus on three such results from the LSND, MiniBooNE (MB), and ATOMKI experiments. A 17 MeV pseudoscalar mediator (a′) can account for two (8Be and 4He) out of the three cases in which excess events have been seen in pair creation transitions in ATOMKI. We incorporate this mediator in a gauge invariant extension of the Standard Model (SM) with a second Higgs doublet and three singlet (seesaw) neutrinos (Ni, i = 1, 2, 3). N1,2 participate in an interaction in MB and LSND which, with a′ as mediator, leads to the production of e+e− pairs. The Ni also lead to mass-squared differences for SM neutrinos in agreement with global oscillation data. We first show that such a model offers a natural joint solution to the MB and LSND excesses, providing excellent fits to their data. Next, using the values of the couplings to the quarks and electrons which are required to explain pair creation nuclear transition data for 8Be and 4He in ATOMKI, we show that these values still lead to fits for MB and LSND data. However, once ATOMKI is incorporated, we find that strong constraints from the decays K+ → π+a′ (a′ → e+e−) and π+ → e+νee+e− come into play. While our solution is in conformity with the bounds on the former decay, it remains in tension with 90% CL bounds on the latter. We also discuss other constraints from both collider and non-collider experiments and from electroweak precision data, stability and unitarity. We compute the contributions to the electron and muon g – 2 up to two loops for our model. We discuss tests of the model in upcoming experiments.
Flavon signatures at the HL-LHC M. A. Arroyo-Ureña, Amit Chakraborty, J. Lorenzo Díaz-Cruz, Dilip Kumar Ghosh, Najimuddin Khan, Stefano Moretti Physical Review D, 2023 The detection of a single Higgs boson at the Large Hadron Collider (LHC) has allowed one to probe some properties of it, including the Yukawa and gauge couplings. However, in order to probe the Higgs potential, one has to rely on new production mechanisms, such as Higgs pair production. In this paper, we show that such a channel is also sensitive to the production and decay of a so-called `Flavon' field ($H_F$), a new scalar state that arises in models that attempt to explain the hierarchy of the Standard Model (SM) fermion masses. Our analysis also focuses on the other decay channels involving the Flavon particle, specifically the decay of the Flavon to a pair of $Z$ bosons ($H_F \\to Z Z$) and the concurrent production of a top quark and charm quark ($H_F\\to tc$), having one or more leptons in the final states. In particular, we show that, with 3000 fb$^{-1}$ of accumulated data at 14 TeV (the Run 3 stage) of the LHC an heavy Flavon $H_F$ with mass $M_{H_F} \\simeq 2m_t $ can be explored with $3\\sigma -5\\sigma $ significance through these channels.
Origin of neutrino masses, dark matter, leptogenesis, and inflation in a seesaw model with triplets Pritam Das, Najimuddin Khan Physical Review D, 2023 We consider a new physics model, where the Standard Model (SM) is extended by hyperchargeless $Y=0$ triplet fermions and Higgs triplet with hypercharge $Y=2$. The first two generation fermion triplets are even under the $Z_2$ transformation. In contrast, the third fermion triplet and scalar triplet are odd under the same $Z_2$ transformation. It is a unifying framework for the simultaneous explanation of neutrino mass and mixing, dark matter, baryogenesis, inflation, and reheating temperature of the Universe. The two $Z_2$ even neutral fermions explain the neutrino low energy variables, whereas the third one can serve as a viable dark matter candidate, explaining the exact relic density. The scalar triplet is coupled nonminimally to gravity and forms the inflaton. We calculate the inflationary parameters and find them consistent with the new Planck-2018 constraints. We also do the reheating analysis for the inflaton decays/annihilations to relativistic SM particles. The triplet fermions associated with $Z_2$ even sector can provide the observed baryon asymmetry of the Universe at the TeV scale.
The stability analysis of the extended singlet scalar model with two high scale minima Najimuddin Khan Nuclear Physics B, 2022 We study the simplest viable dark matter (DM) model with a real singlet scalar, vector-like singlet, and doublet fermions. The Yukawa couplings associated with the fermion sector are important in obtaining the current DM relic density through Freeze-out and Freeze-in mechanisms. In addition to the standard model-like high scale minima along the Higgs field, we find other high scale minima along the singlet scalar field direction. The other minima appears due to the renormalisation group evolutions of the couplings involving the gauge sector, Higgs portal, and the new Yukawa sector. A detailed study of the parameter space identifying the region of electroweak vacuum stability and metastability along different directions of the scalar field is carried out using different phase diagrams.
Exploring the dark sector of the inspired FNSM at the LHC A Chakraborty, DK Ghosh, N Khan, S Moretti Nuclear Physics B, 117389 , 2026 2026 Citations: 1
Scotogenic model with U (1) symmetry and a scalar dark matter AK Barik, N Khan, SK Rai Physical Review D 111 (7), 075023 , 2025 2025 Citations: 2
Finding flavons at colliders G Abbas, A Kumar Alok, NRS Chundawat, N Khan, N Singh Physical Review D 110 (11), 115015 , 2024 2024 Citations: 8
A model of light pseudoscalar dark matter S Chakdar, DK Ghosh, PQ Hung, N Khan, D Nanda Nuclear Physics B 1008, 116721 , 2024 2024 Citations: 1
The Role of a 17 MeV Pseudoscalar in Resolving LSND, MiniBooNE, and ATOMKI Anomalies S Roy, W Abdallah, R Gandhi, T Ghosh, N Khan, S Roy International Conference on Interconnections between Particle Physics and … , 2024 2024
A 17 MeV pseudoscalar and the LSND, MiniBooNE and ATOMKI anomalies W Abdallah, R Gandhi, T Ghosh, N Khan, S Roy, S Roy Journal of High Energy Physics 2024 (10), 1-44 , 2024 2024 Citations: 10
Finding flavon G Abbas, AK Alok, NR Singh Chundawat, N Khan, N Singh arXiv e-prints, arXiv: 2407.09255 , 2024 2024
Exploring the dark sector of the extended FNSM at the LHC A Chakraborty, DK Ghosh, N Khan, S Moretti arXiv , 2024 2024
Role of Plant Growth Promoting Rhizobacteria (PGPR) as a Plant Growth Enhancer for Sustainable Agriculture: A Review. Bacteria 2024, 3, 59–75 A Hasan, B Tabassum, M Hashim, N Khan Interaction between Plants and PGPR for Sustainable Development 1 , 2024 2024 Citations: 8
Flavon signatures at the HL-LHC MA Arroyo-Ureña, A Chakraborty, JL Díaz-Cruz, DK Ghosh, N Khan, ... Physical Review D 108 (9), 095026 , 2023 2023 Citations: 6
Origin of neutrino masses, dark matter, leptogenesis, and inflation in a seesaw model with triplets P Das, N Khan Physical Review D 107 (7), 075008 , 2023 2023 Citations: 3
Dark matter within the framework of minimal extended seesaw N KHAN Harish-Chandra Research Institute , 2022 2022
Three Higgs-Doublet Dark Matter Model N Khan, P Das, MK Das High Energy Physics Symposium, 620-621 , 2022 2022
A Minimal Dark Matter Model with Vector Like Fermions N Khan, P Das, MK Das High Energy Physics Symposium, 617-619 , 2022 2022
The stability analysis of the extended singlet scalar model with two high scale minima N Khan Nuclear Physics B 985, 116015 , 2022 2022 Citations: 1
Feasibility Study on the Development of PGS-Based Flexible Radiator for Deep Space Applications NA Khan, SS Sisodia, VK Singh, P Das, RR Bhavsar, A Elayaperumal Advances in Thermal Sciences: Select Proceedings of ICFAMMT 2022, 257-267 , 2022 2022
Leptogenesis in a Multi-Higgs Doublet Model P Das, M Kumar Das, N Khan Proceedings of the XXIV DAE-BRNS High Energy Physics Symposium, Jatni, India … , 2022 2022
Five-zero texture in neutrino-dark matter model within the framework of minimal extended seesaw P Das, MK Das, N Khan Nuclear Physics B 980, 115810 , 2022 2022 Citations: 6
Higgs Pair Production at the LHC through the Flavon MA Arroyo-Ureña, A Chakraborty, JL Díaz-Cruz, DK Ghosh, N Khan, ... 2022 Citations: 3
The FIMP-WIMP dark matter in the extended singlet scalar model P Das, MK Das, N Khan Nuclear Physics B 975, 115677 , 2022 2022 Citations: 25
MOST CITED SCHOLAR PUBLICATIONS
Exploring collider signatures of the inert Higgs doublet model A Datta, N Ganguly, N Khan, S Rakshit Physical Review D 95 (1), 015017 , 2017 2017 Citations: 97
A study of electroweak vacuum metastability with a singlet scalar dark matter N Khan, S Rakshit arXiv preprint arXiv:1407.6015 , 2014 2014 Citations: 88
Constraints on inert dark matter from metastability of the electroweak vacuum N Khan, S Rakshit arXiv preprint arXiv:1503.03085 , 2015 2015 Citations: 75
Exploring the hyperchargeless Higgs triplet model up to the Planck scale N Khan The European Physical Journal C 78 (4), 341 , 2018 2018 Citations: 64
Electroweak vacuum stability in presence of singlet scalar dark matter in TeV scale seesaw models I Garg, S Goswami, KN Vishnudath, N Khan Physical Review D 96 (5), 055020 , 2017 2017 Citations: 46
Constraining the minimal type-III seesaw model with naturalness, lepton flavor violation, and electroweak vacuum stability S Goswami, V KN, N Khan Physical Review D 99 (7), 075012 , 2019 2019 Citations: 38
The FIMP-WIMP dark matter in the extended singlet scalar model P Das, MK Das, N Khan Nuclear Physics B 975, 115677 , 2022 2022 Citations: 25
Phenomenological study of neutrino mass, dark matter and baryogenesis within the framework of minimal extended seesaw P Das, MK Das, N Khan Journal of High Energy Physics 2020 (3), 18 , 2020 2020 Citations: 24
Electroweakino searches at the HL-LHC in the baryon number violating MSSM RK Barman, B Bhattacherjee, I Chakraborty, A Choudhury, N Khan Physical Review D 103 (1), 015003 , 2021 2021 Citations: 17
Searching for heavy Higgs in supersymmetric final states at the LHC A Adhikary, B Bhattacherjee, RM Godbole, N Khan, S Kulkarni Journal of High Energy Physics 2021 (4), 284 , 2021 2021 Citations: 16
A 17 MeV pseudoscalar and the LSND, MiniBooNE and ATOMKI anomalies W Abdallah, R Gandhi, T Ghosh, N Khan, S Roy, S Roy Journal of High Energy Physics 2024 (10), 1-44 , 2024 2024 Citations: 10
A new feasible dark matter region in the singlet scalar scotogenic model P Das, MK Das, N Khan Nuclear Physics B 964, 115307 , 2021 2021 Citations: 10
Dark matter candidate in an extended type III seesaw scenario A Chaudhuri, N Khan, B Mukhopadhyaya, S Rakshit Physical Review D 91 (5), 055024 , 2015 2015 Citations: 10
Finding flavons at colliders G Abbas, A Kumar Alok, NRS Chundawat, N Khan, N Singh Physical Review D 110 (11), 115015 , 2024 2024 Citations: 8
Role of Plant Growth Promoting Rhizobacteria (PGPR) as a Plant Growth Enhancer for Sustainable Agriculture: A Review. Bacteria 2024, 3, 59–75 A Hasan, B Tabassum, M Hashim, N Khan Interaction between Plants and PGPR for Sustainable Development 1 , 2024 2024 Citations: 8
Supergravity model of inflation and explaining IceCube HESE data via PeV dark matter decay GK Chakravarty, N Khan, S Mohanty Advances in High Energy Physics 2020 (1), 2478190 , 2020 2020 Citations: 8
Anatomy of heavy gauge bosons in a left-right supersymmetric model B Bhattacherjee, N Khan, A Patra Physical Review D 100 (7), 075010 , 2019 2019 Citations: 8
Exploring extensions of the scalar sector of the standard model N Khan arXiv preprint arXiv:1701.02205 , 2017 2017 Citations: 8
Evaluation of body shape variation of indigenous and exotic Anabas testudineus (Bloch, 1792) in Bangladesh by geometric morphometric analyses I Parvez, T Mahajebin, TR Barman, N Khan, MS Chhanda, MA Alam AACL Bioflux 13 (5), 2852-2858 , 2020 2020 Citations: 7
Flavon signatures at the HL-LHC MA Arroyo-Ureña, A Chakraborty, JL Díaz-Cruz, DK Ghosh, N Khan, ... Physical Review D 108 (9), 095026 , 2023 2023 Citations: 6
