HEP Phenomenology·hep-ph

Fri·Dec 30, 2022Friday·December 30, 2022

12 papers—9 primary·3 cross-listed·reconstructed*

01*
Three-loop helicity amplitudes for photon+jet production
Piotr Bargiela🇬🇧 · Amlan Chakraborty🇺🇸 · Giulio Gambuti🇬🇧
We present three-loop helicity amplitudes for the production of a single photon in association with one jet in Quantum Chromodynamics, a final state which provides a standard candle of the Standard Model at the Large Hadron Collider. We employ a recently-proposed variation of the so-called tensor projection method in the 't Hooft-Veltman scheme (tHV) which avoids the computation of contributions due to unphysical (-2 $ϵ$ )-dimensional polarisations of the external states. We obtain compact analytic results expressed in terms of harmonic polylogarithms.
hep-phPRD(2023)·10 citations
02*
Probing sterile neutrino dark matter in the PTOLEMY-like experiment
Ki-Young Choi🇰🇷 · Erdenebulgan Lkhagvadorj🇰🇷 · Seong Moon Yoo🇰🇷
We study the prospect to detect the cosmic background of sterile neutrinos in the Tritium $β$ -decay, such as PTOLEMY-like experiments. The sterile neutrino with mass between 1 eV - 10 keV may contribute to the local density as warm or cold DM component. In this study, we investigate the possibility for searching them in the models with different production in the early Universe, without assuming sterile neutrino as full dark matter component. In these models, especially with low-reheating temperature or phase transition, the capture rate per year can be greatly enhanced to be $O (10)$ without violating other astrophysical and cosmological observations.
hep-phastro-ph.COJCAP(2023)·6 citations
03*
The flavor transition process $b \to s γ$ in the $U (1)_{X}$ SSM with the mass insertion approximation
Xin-Xin Long🇨🇳 · Shu-Min Zhao🇨🇳 · Xi Wang🇨🇳 · Yi-Tong Wang🇨🇳 · Tong-Tong Wang🇨🇳 · Jian-Bin Chen🇨🇳 · Hai-Bin Zhang🇨🇳 · Tai-Fu Feng🇨🇳
People extend the MSSM with the local gauge group $U (1)_{X}$ to obtain the $U (1)_{X}$ SSM. In the framework of the $U (1)_{X}$ SSM, we study the flavor transition process $b \to s γ$ with the mass insertion approximation (MIA). By the MIA method and some reasonable parameter assumptions, we can intuitively find the parameters that have obvious effect on the analytic results of the flavor transition process $b \to s γ$ . By means of the influences of different sensitive parameters, we can obtain reasonable results to better fit the experimental data.
hep-phNPB(2024)·3 citations
04*
Small-x resummation in PDF fits and future prospects
Marco Bonvini🇮🇹
I review recent progress in the determination of PDFs with the inclusion of small-x resummation, and its impact in precision phenomenology, and discuss future prospects.
hep-phActa Phys.Polon.Supp.(2023)·2 citations
05*
The $S$ - and $P$ -wave fully charmed tetraquark states and their radial excitations
Guo-Liang Yu🇨🇳 · Zhen-Yu Li🇨🇳 · Zhi-Gang Wang🇨🇳 · Jie Lu🇨🇳 · Meng Yan🇨🇳
Inspired by recent progresses in observations of the fully charmed tetraquark states by LHCb, CMS, and ATLAS Collaborations, we perform a systematic study of the ground states and the first radial excitations of the $S$ - and $P$ -wave $cc c ˉ c ˉ$ system. Their mass spectra, root mean square(r.m.s.) radii and radial density distributions are studied with the relativized quark model. The calculations show that there is no stable bound states for the full-charmed tetraquark states, and the r.m.s. radii of these tetraquark states are smaller than 1 fm. Our results support assigning X(6600) structure, $M_{X (6600)} = 6552 \pm 10 \pm 12$ MeV, as one of the $0^{++}$ (1 $S$ ) and $2^{++}$ (1 $S$ ) states or their mixtures. Another structure also named as X(6600) by CMS Collaboration, $M_{X (6600)} = 6.62 \pm 0.0 3_{- 0.01}^{+ 0.02}$ GeV, may arise from the lowest 1 $P$ states with $J^{P C}$ = $0^{-+}$ , $1^{-+}$ , and $2^{-+}$ . The possible assignments for X(6900) include the $0^{++}$ (2 $S$ ), $2^{++}$ (2 $S$ ) states, and the highest 1 $P$ state with $J^{P C} = 0^{-+}$ . As for X(7200), it can be interpreted as one of the highest 2 $P$ states with $J^{P C} = 0^{-+}$ , $1^{-+}$ , and $2^{-+}$ , and the 3 $S$ states can not be completely excluded from the candidates.
hep-phEPJC(2023)·57 citations
06*
Dark Matter Bound States: A Window into the Early Universe
Juri Smirnov🇬🇧
Despite significant experimental sensitivity to point-like, weakly interacting particles at the electroweak mass scale, dark matter has not been found yet. This could hint at a more complex dark sector with multiple states or composite dark particles, much like the complexity of the standard model. Currently, our experimental sensitivity to such scenarios is limited by a lack of theoretical understanding. The investigation of Dark Matter systems with unstable or stable bound states provides a playground that leads to the development of important tools needed for the understanding of dark sectors with complex phenomena and allows to experimentally test well-motivated DM scenarios.
hep-phSciPost Phys.Proc.(2023)·22 citations
07*
Discovery prospects of a light charged Higgs near the fermiophobic region of Type-I 2HDM
Disha Bhatia🇧🇷 · Nishita Desai🇮🇳 · Siddharth Dwivedi🇮🇳
Determining if the SM-like Higgs is part of an extended Higgs sector is the most important question to be asked after discovery. A light charged Higgs boson with mass smaller than the sum of top and bottom quarks is naturally allowed in Type-I two Higgs doublet model and can be produced in association with neutral scalars for large parts of parameter space at the LHC. Such low mass charged scalars typically have dominant decays to the fermionic modes viz. $τ ν$ and $cs$ . However in the presence of light neutral scalar ( $φ$ ), the charged Higgs boson has a substantial branching fraction into the bosonic decay modes $H^{\pm} \to W^{(*)} φ$ . Identifying the heavier neutral Higgs ( $H$ ) with the observed 125 GeV Higgs and working in the limit $M_{H^{\pm}} \approx M_{A}$ , we examine charged Higgs production and decay in the bosonic mode $pp \to H^{\pm} h \to W^{(*)} hh$ . The presence of two light Higgses ( $h$ ) is then the key to identifying charged Higgs production. The light Higgs branching ratio is largely dominated by the $b b ˉ$ mode except when close to the fermiophobic limit. Here, the rates into $b b ˉ$ and $γ γ$ can be comparable and we can use the $γ γ b b ˉ$ signature. This signature is complementary to the $hh \to 4 γ$ which has been previously discussed in literature. Using the lepton from the $W$ boson, we demonstrate with a cut-and-count analysis that both the new light neutral Higgs as well as charged Higgs can be probed with reasonable significance at 13.6 TeV LHC with 300-3000 fb $^{- 1}$ of integrated luminosity.
hep-phJHEP(2023)·10 citations
08*
A parton branching algorithm with transverse momentum dependent splitting functions
Aleksandra Lelek🇧🇪
Parton branching methods underlie the Monte Carlo (MC) generators, being therefore of key importance for obtaining high energy physics predictions. We construct a new parton branching algorithm which for the first time incorporates the off-shell, transverse-momentum dependent (TMD) splitting functions, defined from the high-energy limit of partonic decay amplitudes. Based on these TMD splitting functions we construct a new TMD Sudakov form factor. We present the first MC implementation of the algorithm for the evolution of the TMD and integrated parton distribution functions (PDFs). We use this implementation to evaluate small- $x$ corrections to the distributions and to verify the momentum sum rule. The presented study is a first step towards a full TMD MC generator covering the small- $x$ phase space.
hep-phActa Phys.Polon.Supp.(2023)·0 citations
09*
Connecting Euclidean to light-cone correlations: From flavor nonsinglet in forward kinematics to flavor singlet in non-forward kinematics
Fei Yao🇨🇳 · Yao Ji🇩🇪 · Jian-Hui Zhang🇨🇳
We present a unified framework for the perturbative factorization connecting Euclidean correlations to light-cone correlations. Starting from nonlocal quark and gluon bilinear correlators, we derive the relevant hard-matching kernel up to the next-to-leading-order, both for the flavor singlet and non-singlet combinations, in non-forward and forward kinematics, and in coordinate and momentum space. The results for the generalized distribution functions (GPDs), parton distribution functions (PDFs), and distribution amplitudes (DAs) are obtained by choosing appropriate kinematics. The renormalization and matching are done in a state-of-the-art scheme. We also clarify some issues raised on the perturbative matching of GPDs in the literature. Our results provide a complete manual for extracting all leading-twist GPDs, PDFs as well as DAs from lattice simulations of Euclidean correlations in a state-of-the-art strategy, either in coordinate or in momentum space factorization approach.
hep-phhep-latnucl-thJHEP(2023)·38 citations
10*
Full higher-dimensional analysis of moduli oscillation and radiation in expanding universe
Hajime Otsuka🇯🇵 · Yutaka Sakamura🇯🇵
We investigate effects of the radiation and the moduli oscillation around the stabilized values on the evolution of a 6-dimensional spacetime compactified on $S^{2}$ . In order to see the transition from the 5-dimensional space to the 3-dimensional one, we develop a procedure to pursue the spacetime evolution with appropriate approximations, which is valid until the spacetime behaves like 4-dimensional. In the case that the moduli stabilization process cannot be described in the context of the 4-dimensional effective theory, it takes quite a long time for the moduli oscillation to dominate the total energy density, in contrast to the conventional result obtained by the 4-dimensional effective theory approach. We also found that even if the moduli are set at the stabilized values, they start to oscillate due to the pressure in the extra space $S^{2}$ in some cases.
↳ hep-thhep-phJHEP(2023)·4 citations
11*
New description of the scaling evolution of the cosmological magneto-hydrodynamic system
Fumio Uchida🇯🇵 · Motoko Fujiwara🇩🇪 · Kohei Kamada🇯🇵 · Jun'ichi Yokoyama🇯🇵
We present a new description of cosmological evolution of the primordial magnetic field under the condition that it is non-helical and its energy density is larger than the kinetic energy density. We argue that the evolution can be described by four different regimes, according to whether the decay dynamics is linear or not, and whether the dominant dissipation term is the shear viscosity or the drag force. Using this classification and conservation of the Hosking integral, we present analytic models to adequately interpret the results of various numerical simulations of field evolution with variety of initial conditions. It is found that, contrary to the conventional wisdom, the decay of the field is generally slow, exhibiting the inverse transfer, because of the conservation of the Hosking integral. Using the description proposed here, we may trace the intermediate evolution history of the magnetic field and clarify whether each process governing its evolution is frozen or not, which is essential to follow the evolution of relatively weak magnetic fields.
↳ astro-ph.COhep-phphysics.flu-dynPLB(2023)·9 citations
12*
Global angular momentum generation in heavy-ion reactions within a hadronic transport approach
Nils Sass🇩🇪 · Marco Müller🇩🇪 · Oscar Garcia-Montero🇩🇪 · Hannah Elfner🇩🇪
In 2017, the STAR collaboration at the Relativistic Heavy Ion Collider (RHIC) has measured finite global angular momentum in heavy-ion collisions through a spin polarization measurement of $Λ$ hyperons. This measurement revealed a high angular momentum of the heavy ions and provided experimental evidence for vorticity in the quark-gluon plasma (QGP) for the first time. In order to investigate the underlying mechanisms, a dynamic description of the transfer of angular momentum is required. In this work, the microscopic non-equilibrium transport approach SMASH (Simulating Many Accelerated Strongly-interacting Hadrons) is applied to study the generation of global angular momentum by the interaction of two nuclei. As SMASH provides access to the whole phase-space evolution of every particle at any given time, it allows to assess the fraction of angular momentum generated in the fireball by all participants. We confirm the previous modeling by Becattini \textit{et al} within a geometric Glauber model approach, which found that the angular momentum transfer reaches a unique maximum in mid-central collisions during time evolution. The corresponding impact parameter is around $b = 4 - 6$ fm for all beam energies from $s_{NN} = 2.41 - 200$ GeV. Even though angular momentum is not conserved locally in the transport approach a priori, we identify the contributions to the conservation violation and propose optimal setups for different energy regimes that recover conservation, based upon the test particle method and the treatment of Fermi motion. Furthermore, the system size and centrality dependence are investigated.
↳ nucl-thhep-phPRC(2023)·15 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.