arXiv subjects

Jingya Zhu

Publications and source records attributed to Jingya Zhu.

At least 37 records · Page 2Linked to original sources

arXiv2022

The possible assignments of the scalar $K_0^(1950)$ and $K_0^(2130)$ within the $^3P_0$ model

We have evaluated the strong decays of the $K_0^*(1950)$ and $K_0^*(2130)$ within the $^3P_0$ model, by employing the meson wave functions from the relativized quark model. By comparing with the experimental measurements, the $K_0^*(2130)$ could be assigned as $K_0^*(3^3P_0)$, while the $K_0^*(1950)$ seems like an exotic state, because its width can not be reasonably reproduced within the $^3P_0$ model. We also predict that the $K_0^*(2^3P_0)$ state has a mass of about $1811$ MeV and a width of about $656$ MeV, while the $K_0^*(4^3P_0)$ state has a mass of about $2404$ MeV and a width of about $180$ MeV.

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arXiv2022

Canonical interpretation of the $D_{s0}(2590)^{+}$ resonance

The $D_{s0}(2590)^{+}$ resonance observed by LHCb Collaboration is a strong candidate of the $D_{s}(2^1S_0)$ state according to its spin parity and strong decay mode. However, the measured mass seems relatively lower than the previous theoretical predictions, which interests the coupled channel interpretations in the literature. In this work, we adopt an alternate approach, taking into account the screening effects in the potential model, to describe the $D_{s0}(2590)^{+}$ resonance. The mass spectrum and strong decays of the excited charmed-strange mesons are investigated within the modified relativized quark model and $^3P_0$ model. The calculated mass and width of the $D_{s0}(2590)^{+}$ are consistent with the experimental observations, which indicate that it can be reasonably interpreted as the $D_{s}(2^{1}S_{0})$ state.

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arXiv2021

A smuon in the NMSSM confronted with the muon g-2 and SUSY searches

Motivated by the recent supersymmetry (SUSY) search results which prefer most SUSY particles heavy, and muon g-2 anomaly which prefers colorless SUSY particles light, we explore the status of a light smuon (the SUSY partner of left-handed muon lepton) in the Next-to-Minimal Supersymmetric Standard Model (NMSSM). Assuming colored SUSY particles be heavy, and considering numerous experimental constraints including muon g-2, SUSY searches, and dark matter, we scan the parameter space in the NMSSM with Z3-symmetry, checking the status of colorless SUSY particles and their possible mass order, and paying special attention to the smuon. After calculation and discussions, we draw the following conclusions: (i) The dominated SUSY contributions to muon g-2 come from the chargino-sneutrino loops, but the muon g-2 anomaly can also constrain the mass of smuon seriously because of the mass-degenerate relation between smuon and muon sneutrino. To interpret the muon g-2 anomaly at $1σ$ ($2σ$) level, the smuon need to be lighter than 1 TeV (1.8 TeV). (ii) When $\tildeχ^0_1$ is wino- or higgsino-dominated, the smuon can escape from the direct searches with low mass, e.g., 300 GeV. (iii) When smuon and $\tildeχ^0_1$ are mass-degenerate, the smuon can be as light as 200 GeV, while the $\tildeχ^0_1$ is usually bino-dominated, or some singlino-dominated, and its relic density can most likely reach the observed value, and the dominated annihilating mechanism is slepton annihilations. In addition, we also list several benchmark points for further studies.

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arXiv2020

Higgsino Asymmetry and Direct-Detection Constraints of Light Dark Matter in the NMSSM with Non-Universal Higgs Masses

In this work, we study the direct-detection constraints of light dark matter in the next-to minimal supersymmetric standard model (NMSSM) with non-universal Higgs masses (NUHM), especially the correlation between higgsino asymmetry and spin-dependent cross section. Finally, we get the following conclusions: (i) The spin-dependent cross section is proportional to the square of higgsino asymmetry in dark matter $\tildeχ^0_1$ in the NMSSM-NUHM. (ii) For highly singlino-dominated dark matter $\tildeχ^0_1$, the relic density can be sufficient, but the higgsino asymmetry and spin-dependent cross section is always small. (iii) With a sizeable higgsino component in the light dark matter, the higgsino asymmetry and spin-dependent cross section can be sizeable, but dark matter relic density is always small, thus it can escape the direct detections. (iv) Light dark matter in the $h_2$- and $Z$-funnel annihilation channels with sufficient relic density can be covered by future LUX-ZEPLIN (LZ) 7-ton in spin-dependent detections.

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arXiv2020

Higgs decay to light scalars in the semi-constrained NMSSM

The next-to minimal supersymmetric standard model (NMSSM) with non-universal Higgs masses, or the semi-constrained NMSSM (scNMSSM), extend the minimal supersymmetric standard model (MSSM) by a singlet superfield and assume universal conditions except for the Higgs sector. It can not only keep the simpleness and grace of the fully constrained MSSM and NMSSM, and relax the tension that they face after the 125-GeV Higgs boson discovered, but also predict an exotic phenomenon that Higgs decay to a pair of light singlet-dominated scalars ($10\!\sim\! 60\;{\rm GeV}$). This condition can be classified to three scenarios according to the identities of the SM-like Higgs and the light scalar: (i) the light scalar is CP-odd, and the SM-like Higgs is $h_2$; (ii) the light scalar is CP-odd, and the SM-like Higgs is $h_1$; (iii) the light scalar is CP-even, and the SM-like Higgs is $h_2$. In this work, we compare the three scenarios, checking the interesting parameter schemes that lead to the scenarios, the mixing levels of the doublets and singlets, the tri-scalar coupling between the SM-like Higgs and a pair of light scalars, the branching ratio of Higgs decay to the light scalars, and sensitivities in hunting for the exotic decay at the HL-LHC and the future lepton colliders such as CEPC, FCC-ee, and ILC.

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arXiv2020

A Novel Scenario in the Semi-constrained NMSSM

In this work, we develop a novel efficient scan method, combining the Heuristically Search (HS) and the Generative Adversarial Network (GAN), where the HS can shift marginal samples to perfect samples, and the GAN can generate a huge amount of recommended samples from noise in a short time. With this efficient method, we find a new scenario in the semi-constrained Next-to Minimal Supersymmetric Standard Model (scNMSSM), or NMSSM with non-universal Higgs masses. In this scenario, (i) Both muon g-2 and right relic density can be satisfied, along with the high mass bound of gluino, etc. As far as we know, that had not been realized in the scNMSSM before this work. (ii) With the right relic density, the lightest neutralinos are singlino-dominated, and can be as light as 0-12 GeV. (iii) The future direct detections XENONnT and LUX-ZEPLIN (LZ-7 2T) can give strong constraints to this scenario. (iv) The current indirect constraints to Higgs invisible decay $h_2\to \tildeχ^0_1 \tildeχ^0_1$ are weak, but the direct detection of Higgs invisible decay at the future HL-LHC may cover half of the samples, and that of the CEPC may cover most. (v) The branching ratio of Higgs exotic decay $h_2\to h_1h_1, a_1a_1$ can be over 20 percent, while their contributions to the invisible decay $h_2\to4χ_1^0$ are very small.

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arXiv2020

The Light Higgsino-dominated NLSPs in the Semi-constrained NMSSM

In the semi-constrained NMSSM (scNMSSM, or NMSSM with non-universal Higgs mass) under current constraints, we consider a scenario where $h_2$ is the SM-like Higgs, $\tildeχ^0_1$ is singlino-dominated LSP, $\tildeχ^{\pm}_1$ and $\tildeχ^0_{2,3}$ are mass-degenerated, light and higgsino-dominated NLSPs (next-to-lightest supersymmetric particles). We investigate the constraints to these NLSPs from searching for SUSY particles at the LHC Run-I and Run-II, discuss the possibility of discovering these NLSPs in the future, and come to the following conclusions: (i) With all data of Run I and up to 36 $\rm fb^{-1}$ data of Run II at the LHC, the search results by ATLAS and CMS can still not exclude the higgsino-dominated NLSPs of $100\sim200$ GeV. (ii) When the mass difference with $\tildeχ^0_{1}$ is smaller than $m_{h_2}$, $\tildeχ^0_{2}$ and $\tildeχ^0_{3}$ have opposite preference on decaying to $Z/Z^*$ or $h_1$. (iii) When the mass difference between NLSP and LSP is larger than $m_Z$, most of the samples can be checked at $5σ$ level with future 300 $\rm fb^{-1}$ data at the LHC. While with 3000 $\rm fb^{-1}$ data at the High Luminosity LHC (HL-LHC), nearly all of the samples can be checked at $5σ$ level even if the mass difference is insufficient. (iv) The $a_1$ funnel and the $h_2/Z$ funnel mechanisms for the singlino-dominated LSP annihilating can not be distinguished by searching for NLSPs.

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arXiv2020

Funnel annihilations of light dark matter and the invisible decay of the Higgs boson

The semi-constrained NMSSM (scNMSSM), or NMSSM with non-universal Higgs masses, can naturally predict a light dark matter under current constraints including Higgs data, sparticle-mass bounds, dark matter searches, and muon g-2, etc. In this work, we take this scenario of scNMSSM as an example to study the funnel-annihilation mechanisms of light dark matter ($1\!\thicksim\!62$ GeV) and the invisible Higgs decay. In this scenario we found that: (i) There can be four funnel-annihilation mechanisms for the LSP $\tildeχ^0_1$, which are the $h_2$, $Z$, $h_1$ and $a_1$ funnel. (ii) For the $h_1$ and $a_1$ funnel with right relic density, the $\tildeχ^0_1$ mass is lighter than 12 GeV, and the invisible Higgs decay can be $2\%$ at most. (iii) For the $h_2$ and $Z$ funnel with right relic density, the invisible Higgs decay can be about $0.4\%$ and $1\%$ respectively at most. (iv) If the invisible Higgs decay was discovered at the HL-LHC, the four funnel-annihilation mechanisms of light dark matter may be all excluded with $\tildeχ^0_1$ as the only dark matter source. Four benchmark points, one for each mechanism, are proposed for future checking with updated experimental results.

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arXiv2018

Solving the muon g-2 anomaly in CMSSM extension with non-universal gaugino masses

We propose to generate non-universal gaugino masses in SU(5) GUT with the generalized Planck-scale mediation SUSY breaking mechanism, in which the non-universality arises from proper wavefunction normalization with lowest component VEVs of various high dimensional representations of the Higgs fields of SU(5) and an unique F-term VEV by the singlet. Different predictions on gaugino mass ratios with respect to widely studied scenarios are given. The gluino-SUGRA-like scenario, where gluinos are much heavier than winos, bino and universal scalar masses, can be easily realized with appropriate combinations of such high-representation Higgs fields. With 6 GUT-scale parameters in our scenario, we can solve elegantly the tension between mSUGRA and the present experimental results, including the muon g-2, the dark matter (DM) relic density and the direct sparticle search bounds from the LHC. Taking into account the current constraints in our numerical scan, we have the following observations: (i) The large-$\tanβ$ samples with a moderate $M_3$ a small $|A_0/M_3|$ and a small $m_A$ are favored to generate a 125 GeV SM-like Higgs and predict a large muon g-2, while the stop mass and μparameter, mainly determined by $|M_3|(\gg M_0,|M_1|,|M_2|)$, can be about 6 TeV; (ii) The moderate-$\tanβ$(35~40) samples with a negative $M_3$ can have a light smuon but a heavy stau, which predict a large muon g-2 but a small $Br(B_s\toμ^+μ^-)$; (iii) To obtain the right DM relic density, the annihilation mechanisms should be stau exchange, stau coannihilation, chargino coannihilation, slepton annihilation and the combination of two or three of them; (iv) To obtain the right DM relic density, the spin-independent DM-nucleon cross section is typically much smaller than the present limits of XENON1T 2018 and also an order of magnitude lower than the future detection sensitivity of LZ and XENONnT.

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arXiv2018

A Light Scalar in the Minimal Dilaton Model in Light of LHC Constraints

Whether an additional light scalar exists is an interesting topic beyond the Standard Model (SM), while nowadays we do not know exactly physics beyond the SM in the low mass region, e.g., the Atlas and CMS collaborations get inconsistent results at around 95 GeV in searching for light resonances in diphoton channel. Considering these, we study a light scalar in the Minimal Dilaton Model (MDM). Under the theoretical and latest experimental constraints, we sort the surviving samples into two scenarios according to the diphoton rate of the light scalar: the large-diphoton scenario (with $/SM\gtrsim0.2$) and the small-diphoton scenario (with $/SM\lesssim0.2$), which are favored by CMS and Atlas results respectively. We compare the two scenarios, check the characteristics in model parameters, scalar couplings, production and decay, and consider further distinguishing them at colliders. Finally, we get the following conclusions for the two scenarios: (i) The formal usually has small Higgs-dilaton mixing angle ($|\sinθ_S|\lesssim0.2$) and small dilaton vacuum expectation value (VEV) $f$ ($0.5\lesssimη\equiv v/f\lesssim1$), and the later usually has large mixing ($|\sinθ_S|\gtrsim0.4$) or large VEV ($η\equiv v/f\lesssim0.3$). (ii) The former usually predicts small $sγγ$ coupling ($|C_{sγγ}/SM|\lesssim0.3$) and large $sgg$ coupling ($0.6\lesssim|C_{sgg}/SM|\lesssim1.2$), while the later usually predicts small $sgg$ coupling ($|C_{sgg}/SM|\lesssim0.5$). (iii) The former can interpret the small diphoton excess by CMS at its central value, when $m_s\simeq$95GeV, $η\simeq0.6$ and $|\sinθ_S|\simeq0$. (iv) The former usually predicts a negative correlation between Higgs couplings $|C_{hγγ}/SM|$ and $|C_{hgg}/SM|$, while the later usually predicts the two couplings both smaller than 1, or $|C_{hγγ}/SM|\lesssim0.9 \lesssim|C_{hgg}/SM|$.

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arXiv2018

The semi-constrained NMSSM in light of muon g-2, LHC, and dark matter constraints

The semi-constrained NMSSM (scNMSSM) extends the MSSM by a singlet field, and requires unification of the soft SUSY breaking terms in the squark and slepton sectors, while it allows that in the Higgs sector to be different. We try to interpret the muon g-2 in the scNMSSM, under the constraints of 125 GeV Higgs data, B physics, searches for low and high mass resonances, searches for SUSY particles at the LHC, dark matter relic density by WMAP/Planck, and direct searches for dark matter by LUX, XENON1T, and PandaX-II. We find that under the above constraints, the scNMSSM can still (i) satisfy muon g-2 at 1$σ$ level, with a light muon sneutrino and light chargino; (ii) predict a highly-singlet-dominated 95~GeV Higgs, with a diphoton rate as hinted at by CMS data, because of a light higgsino-like chargino and moderate $λ$; (iii) get low fine tuning from the GUT scale with small $μ_{\rm eff},\, M_0,\, M_{1/2},\, {\rm and}\, A_0$, with a lighter stop mass which can be as low as about 500 GeV, which can be further checked in future studies with search results from the 13~TeV LHC; (iv) have the lightest neutralino be singlino-dominated or higgsino-dominated, while the bino and wino are heavier because of high gluino bounds at the LHC and universal gaugino conditions at the GUT scale; (v) satisfy all the above constraints, although it is not easy for the lightest neutralino, as the only dark matter candidate, to get enough relic density. Several ways to increase relic density are discussed.

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arXiv2016

Interpreting the 750 GeV diphoton excess in the Minimal Dilaton Model

We try to interpret the 750 GeV diphoton excess in the Minimal Dilaton Model, which extends the SM by adding one linearized dilaton field and vector-like fermions. We first show by analytic formulae in this framework that the production rates of the $γγ$, $gg$, $Zγ$, $ZZ$, $WW^\ast$, $t\bar{t}$ and $hh$ signals at the $750 {\rm GeV}$ resonance are only sensitive to the dilaton-Higgs mixing angle $θ_S$ and the parameter $η\equiv v N_X/f$, where $f$ is the dilaton decay constant and $N_X$ denotes the number of the fermions. Then we scan the two parameters by considering various theoretical and experimental constraints to find the solutions to the diphoton excess. We conclude that the model can predict the central value of the diphoton rate without conflicting with any constraints. The signatures of our explanation at the LHC Run II and the vacuum stability at high energy scale are also discussed.

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arXiv2014

Pair production of 125 GeV Higgs boson in the SM extension with color-octet scalars at the LHC

Although the Higgs boson mass and single production rate have been determined more or less precisely, its other properties may deviate significantly from its predictions in the standard model (SM) due to the uncertainty of Higgs data. In this work we study the Higgs pair production at the LHC in the Manohar-Wise model, which extends the SM by one family of color-octet and isospin-doublet scalars. We first scanned over the parameter space of the Manohar-Wise model considering exprimental constraints and performed fits in the model to the latest Higgs data by using the ATLAS and CMS data separately. Then we calculated the Higgs pair production rate and investigated the potential of its discovery at the LHC14. We conclude that: (i) Under current constrains including Higgs data after Run I of the LHC, the cross section of Higgs pair production in the Manohar-Wise model can be enhanced up to even $10^3$ times prediction in the SM. (ii) Moreover, the sizable enhancement comes from the contributions of the CP-odd color-octet scalar $S^A_I$. For lighter scalar $S^A_I$ and larger values of $|λ_I|$, the cross section of Higgs pair production can be much larger. (iii) After running again of LHC at 14 TeV, most of the parameter spaces in the Manohar-Wise model can be test. For an integrated luminosity of 100 fb$^{-1}$ at the LHC14, when the normalized ratio $R=10$, the process of Higgs pair production can be detected.

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arXiv2014

Higgs Phenomenology in the Minimal Dilaton Model after Run I of the LHC

The Minimal Dilaton Model (MDM) extends the Standard Model (SM) by a singlet scalar, which can be viewed as a linear realization of general dilaton field. This new scalar field mixes with the SM Higgs field to form two mass eigenstates with one of them corresponding to the 125 GeV SM-like Higgs boson reported by the LHC experiments. In this work, under various theoretical and experimental constrains, we perform fits to the latest Higgs data and then investigate the phenomenology of Higgs boson in both the heavy dilaton scenario and the light dilaton scenario of the MDM. We find that: (i) If one considers the ATLAS and CMS data separately, the MDM can explain each of them well, but refer to different parameter space due to the apparent difference in the two sets of data. If one considers the combined data of the LHC and Tevatron, however, the explanation given by the MDM is not much better than the SM, and the dilaton component in the 125-GeV Higgs is less than about 20% at 2 sigma level. (ii) The current Higgs data have stronger constrains on the light dilaton scenario than on the heavy dilaton scenario. (iii) The heavy dilaton scenario can produce a Higgs triple self coupling much larger than the SM value, and thus a significantly enhanced Higgs pair cross section at hadron colliders. With a luminosity of 100 fb^{-1} (10 fb^{-1}) at the 14-TeV LHC, a heavy dilaton of 400 GeV (500 GeV) can be examined. (iv) In the light dilaton scenario, the Higgs exotic branching ratio can reach 43% (60%) at 2 sigma (3 sigma) level when considering only the CMS data, which may be detected at the 14-TeV LHC with a luminosity of 300 fb^{-1} and the Higgs Factory.

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arXiv2013

Dark matter in little Higgs model under current experimental constraints from LHC, Planck and Xenon

We examine the status of dark matter (heavy photon) in the littlest Higgs model with T-parity (LHT) in light of the new results from the LHC Higgs search, the Planck dark matter relic density and the XENON100 limit on the dark matter scattering off the nucleon. We obtain the following observations: (i) For the LHC Higgs data, the LHT can well be consistent with the CMS results but disfavored by the ATLAS observation of diphoton enhancement; (ii) For the dark matter relic density, the heavy photon in the LHT can account for the Planck data for the small mass splitting of mirror lepton and heavy photon; (iii) For the dark matter scattering off the nucleon, the heavy photon can give a spin-independent cross section below the XENON100 upper limit for $m_{A_H}>95$ GeV ($f> 665$ GeV); (iv) A fit using the CMS Higgs data gives the lowest chi-square of 2.63 (the SM value is 4.75) at $f\simeq$ 1120 GeV and $m_{A_H}\simeq$ 170 GeV (at this point the dark matter constraints from Planck and XENON100 can also be satisfied). Such a best point and its nearby favored region (even for a $f$ value up to 3.8 TeV) can be covered by the future XENON1T (2017) experiment.

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arXiv2013

A light Higgs scalar in the NMSSM confronted with the latest LHC Higgs data

In the Next-to-Minimal Supersymemtric Standard Model (NMSSM), one of the neutral Higgs scalars (CP-even or CP-odd) may be lighter than half of the SM-like Higgs boson. In this case, the SM-like Higgs boson h can decay into such a light scalar pair and consequently the diphoton and ZZ signal rates at the LHC will be suppressed. In this work, we examine the constraints of the latest LHC Higgs data on such a possibility. We perform a comprehensive scan over the parameter space of the NMSSM by considering various experimental constraints and find that the LHC Higgs data can readily constrain the parameter space and the properties of the light scalar, e.g., at 3 $σ$ level this light scalar should be highly singlet dominant and the branching ratio of the SM-like Higgs boson decay into the scalar pair should be less than about 30%. Also we investigate the detection of this scalar at various colliders. Through a detailed Monte Carlo simulation we find that under the constraints of the current Higgs data this light scalar can be accessible at the LHC-14 with an integrated luminosity over 300 fb$^{-1}$.

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arXiv2013

The SM extension with color-octet scalars: diphoton enhancement and global fit of LHC Higgs data

In light of the significant progress of the LHC to determine the properties of the Higgs boson, we investigate the capability of the Manohar-Wise model in explaining the Higgs data. This model extends the SM by one family of color-octet and isospin-doublet scalars, and it can sizably alter the coupling strengths of the Higgs boson with gluons and photons. We first examine the current constraints on the model, which are from unitarity, the LHC searches for the scalars and the electroweak precision data (EWPD).In implementing the unitarity constraint, we use the properties of the SU(3) group to simplify the calculation. Then in the allowed parameter space we perform a fit of the model, using the latest ATLAS and CMS data, respectively. We find that the Manohar-Wise model is able to explain the data with χ^2 significantly smaller than the SM value. We also find that the current Higgs data, especially the ATLAS data, are very powerful in further constraining the parameter space of the model. In particular, in order to explain the diphoton enhancement reported by the ATLAS collaboration, the sign of the hgg coupling is usually opposite to that in the SM.

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arXiv2013

Little Higgs theory confronted with the LHC Higgs data

We confront the little Higgs theory with the LHC Higgs search data (up to 17 fb$^{-1}$ of the combined 7 and 8 TeV run). Considering some typical models, namely the littlest Higgs model (LH), the littlest Higgs model with T-parity (LHT-A and LHT-B) and the simplest little Higgs model (SLH), we scan over the parameter space in the region allowed by current experiments. We find that in these models the inclusive and exclusive (via gluon-gluon fusion) diphoton and $ZZ^*$ signal rates of the Higgs boson are always suppressed and approach to the SM predictions for a large scale $f$. Thus, the $ZZ^*$ signal rate is within the $1σ$ range of the experimental data while the inclusive diphoton signal rate is always outside the $2σ$ range. Especially, in the LHT-A the diphoton signal rate is outside the $3σ$ range of the experimental data for $f < 800$ GeV. We also perform a global $χ^2$ fit to the available LHC and Tevatron Higgs data, and find that these models provide no better global fit to the whole data set (only for some special channels a better fit can be obtained, specially in the LHT-B).

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