Wed·Jul 20, 2022Wednesday·July 20, 2022

1. 01*

   Dimension-8 SMEFT Matching Conditions for the Low-Energy Effective Field Theory

   Serge Hamoudou🇨🇦 · Jacky Kumar🇩🇪 · David London🇨🇦

   In particle physics, the modern view is to categorize things in terms of effective field theories (EFTs). Above the weak scale, we have the SMEFT, formed when the heavy new physics (NP) is integrated out, and for which the Standard Model (SM) is the leading part. Below $M_W$, we have the LEFT (low-energy EFT), formed when the heavy SM particles ($W^{\pm }$, $Z^0$, $H$, $t$) are also integrated out. In order to determine how low-energy measurements depend on the underlying NP, it is necessary to compute the matching conditions of LEFT operators to SMEFT operators. These matching conditions have been worked out for all LEFT operators up to dimension 6 in terms of SMEFT operators up to dimension 6 at the one-loop level. However, this is not sufficient for all low-energy observables. In this paper we present the momentum-independent matching conditions of all such LEFT operators to SMEFT operators up to dimension 8 at tree level.

   hep-phJHEP(2023)·18 citations
2. 02*

   Snowmass White Paper: New flavors and rich structures in dark sectors

   Philip Harris🇺🇸 · Philip Schuster🇺🇸 · Jure Zupan🇺🇸

   Dark matter can be part of a dark sector with non-minimal couplings to the Standard Model. Compared to many (minimal) benchmark models, such scenarios can result in significant modifications in experimental signatures and strongly impact experimental search sensitivity. In this white paper, we review several non-minimal dark sector models, including phenomenological consequences: models explaining $(g-2{)}_{\mu }$, inelastic dark matter, strongly interacting massive particles as dark matter candidates, and axions with flavorful couplings. The present exclusions and projected experimental sensitivities on these example dark sector models illustrate the robustness of the growing dark sector experimental effort -- both the broadness and the precision of existing searches -- probing theoretically interesting parameter space. They also illustrate some of the unique complementarity of different experimental approaches.

   hep-phhep-ex33 citations
3. 03*

   GM2Calc-2 for the 2HDM

   Peter Athron🇨🇳 · Csaba Balazs🇦🇺 · Adriano Cherchiglia🇧🇷 · Douglas H. J. Jacob🇦🇺 · Dominik Stöckinger🇩🇪 · Hyejung Stöckinger-Kim🇩🇪 · Alexander Voigt🇩🇪

   GM2Calc is a leading tool for calculating precise contributions to $a_{\mu }$ in the Minimal Supersymmetric Standard Model. In this proceeding we detail GM2Calc version 2 where it is extended so it can calculate two-loop contributions to $a_{\mu }$ in the Two-Higgs Doublet Model (2HDM), based on the work in Ref. [1]. The 2HDM is a simple model, yet it is one of the few single field extensions of the Standard Model which is able to explain the muon $g-2$ anomaly. We demonstrate the powerful and flexible 2HDM capabilities of GM2Calc2, which include the most precise contributions in the literature and allow the user to work in their favourite type of the 2HDM as well as use complex and lepton flavour violating couplings. With its multiple interfaces and input flexibility, GM2Calc2 is a powerful tool both as a standalone code and as part of a larger code toolchain.

   hep-phPoS(2022)·5 citations
4. 04*

   IBP reduction via Gröbner bases in a rational double-shift algebra

   Mohamed Barakat🇩🇪 · Robin Brüser🇩🇪 · Tobias Huber🇩🇪 · Jan Piclum🇩🇪

   We report on an approach to integration-by-parts reduction based on Gröbner bases. We establish the underlying noncommutative rational double-shift algebra wherein the integration-by-parts relations form a left ideal. We describe in detail the one-loop massless box as an example where we achieved the full reduction to master integrals by means of the Gröbner basis approach, and report on the performance of the implementation. We also identify potential bottlenecks in more complicated examples and elaborate on interesting further directions.

   hep-phhep-thmath-phmath.MPPoS(2022)·4 citations
5. 05*

   Global analysis of $\psi (2S)$ inclusive hadroproduction at next-to-leading order in nonrelativistic-QCD factorization

   Mathias Butenschoen🇩🇪 · Bernd A. Kniehl🇩🇪

   Working in the nonrelativistic-QCD factorization framework at next-to-leading order in ${\alpha }_s$, we fit the relevant color octet (CO) long-distance matrix elements (LDMEs) of the $\psi (2S)$ meson, $⟨{\mathcal{O}}^{\psi (2S)}({{}^{1}S}_0^{[8]})⟩$, $⟨{\mathcal{O}}^{\psi (2S)}({{}^{3}S}_1^{[8]})⟩$, and $⟨{\mathcal{O}}^{\psi (2S)}({{}^{3}P}_0^{[8]})⟩$, to 1001 data points of upolarized and polarized $\psi (2S)$ inclusive hadroproduction. We do four different fits, with filters on polarization and low to middle transverse momentum $p_T$. We find that a successful description of the data is only possible with a large low-$p_T$ cut. Our results are one order of magnitude more precise than previous determinations of these color octet long-distance matrix elements.

   hep-phhep-exPRD(2023)·21 citations
6. 06*

   Aspects of Heavy Supersymmetry

   Priyanka Lamba🇮🇳

   The discovery of the Higgs boson raises the question of its "lightness" in mass when the Standard Model is considered as an effective quantum field theory. Supersymmetry is the only currently known symmetry which can protect the Higgs mass while still treating the Higgs as an elementary quantum field. However in the view of null experimental confirmation from both direct (LHC) and indirect searches (flavour, dark matter) of the supersymmetric particles and the constraints from the Higgs mass, several possible heavy spectra for supersymmetric partners have been proposed. In the present thesis, we study the possible origins of these heavy spectra by considering a considering many sequestered spurion fields as carriers of supersymmetry breaking. We show that "natural" supersymmetric spectrum is possible in these models and in particular a "coherent" scenario leads to low fine tuning, light Higgsino mixed dark matter ( a la focus point region) even with heavy supersymmetric spectrum. We then consider this model within the context of string landscape, where we use the Bousso-Polchinski framework of four form fluxes to model the spurions. We show that the flavour violating parameters of supersymmetric spectrum can be "diluted" away in the presence of large number of fluxes. One of the possible supersymmetric spectra which emerges by considering all the data is the generation split (Gensplit) spectrum which allows for flavour violation to be present for the first two generations, which are heavy. We study this spectrum within the context of supersymmetric SU(5) and proton decay. The results are quite interesting and dependent on the proton decay mode considered. The strongest bound p to k \nu is now modified depending on the flavour of the neutrino and brings the parameter space within the realms of upcoming experiments of JUNO, DUNE and Hyper K. These results will be discussed.

   hep-ph0 citations
7. 07*

   External-leg corrections as an origin of large logarithms

   Henning Bahl🇺🇸 · Johannes Braathen🇩🇪 · Georg Weiglein🇩🇪

   Obtaining precise theoretical predictions for both production and decay processes of heavy new particles is of great importance to constrain the allowed parameter spaces of Beyond-the-Standard-Model (BSM) theories, and to properly assess the sensitivity for discoveries and for discriminating between different possible BSM scenarios. In this context, it is well known that large logarithmic corrections can appear in the presence of widely separated mass scales. We point out the existence of a new type of possible large, Sudakov-like, logarithms in external-leg corrections of heavy scalars. To the difference of usual Sudakov logarithms, these can furthermore potentially be enhanced by large trilinear couplings. Such large logarithms are associated with infrared singularities and we review several techniques to address these at one loop. In addition to this discussion, we also present the derivation of the two-loop corrections containing this type of large logarithms, pointing out in this context the importance of adopting an on-shell renormalisation scheme. Finally, we illustrate our calculations and examine the possible magnitude of these corrections for a simple scalar toy model as well as for decay processes involving heavy stop quarks in the Minimal Supersymmetric Standard Model and a heavy Higgs boson in the Next-to-Two-Higgs-Doublet Model.

   hep-phPoS(2022)·0 citations
8. 08*

   Heavy meson thresholds in Born-Oppenheimer Effective field theory

   Jaume Tarrús Castellà🇺🇸

   We consider heavy meson-antimeson pairs and their coupling to quarkonium in the context of nonrelativistic EFTs incorporating the adiabatic expansion. We work out all the leading order couplings of quarkonium to heavy meson-antimeson pairs and obtain their contributions to the masses and widths of quarkonia. We match the new potentials terms to NRQCD. Using the available lattice data for the coupled system of quarkonium and the lowest laying heavy meson-antimeson pair, we extract the mixing potential and use it to compute numerically the contributions of $D\bar{D}(B\bar{B})$ and $D_s{\bar{D}}_s(B_s{\bar{B}}_s)$ to the masses and widths of the charmonium (bottomonium) states for $l=0,1,2$ and up to $n=6$ covering the states in threshold region. When a quarkonium state and a heavy meson-antimeson pair are separated by small energy gaps, their interactions can be described by a threshold EFT with contact interactions. We work out the matching between the two EFTs obtaining the couplings of the threshold EFT in terms of the mixing potential and quarkonium wave functions.

   hep-phhep-exhep-latPRD(2022)·24 citations
9. 09*

   Constraints on Nonrelativistic-QCD Long-Distance Matrix Elements from $J/\psi$ Plus $W$/$Z$ Production at the LHC

   Mathias Butenschoen🇩🇪 · Bernd A. Kniehl🇩🇪

   We study the associated production of prompt $J/\psi$ mesons and $W$ or $Z$ bosons within the factorization approach of nonrelativistic QCD (NRQCD) at next-to-leading order in ${\alpha }_s$, via intermediate color singlet ${}^3{S}_1^{[1]}$ and ${}^3{P}_J^{[1]}$ and color octet ${{}^{1}S}_0^{[8]}$, ${{}^{3}S}_1^{[8]}$ and ${{}^{3}P}_J^{[8]}$ states. Requiring for our predictions to be compatible with recent ATLAS measurements yields stringent new constraints on charmonium long-distance matrix elements (LDMEs) being nonperturbative, process-independent input parameters. Considering four popular LDME sets fitted to data of single $J/\psi$ inclusive production, we find that one is marginally compatible with the data, with central predictions typically falling short by a factor of three, one is unfavored, the factor of shortfall being about one order of magnitude, and two violate cross section positivity for direct $J/\psi +W/Z$ production. The large rate of prompt $J/\psi$ plus $W$ production observed by ATLAS provides strong evidence for the color octet mechanism inherent to NRQCD factorization, the leading color singlet contribution entering only at $\mathcal{O}(G_F{\alpha }_s^4)$, beyond the order considered here.

   hep-phhep-exPRL(2023)·15 citations
10. 10*

    Feasibility study for precisely measuring the EIC ${}^3$He beam polarization with the Polarized Atomic Hydrogen Gas Jet Target polarimeter at RHIC

    A. A. Poblaguev🇺🇸

    The Polarized Atomic Hydrogen Gas Jet Target polarimeter (HJET) is used to measure the absolute proton beam polarization, ${\sigma }_P^{\text{syst}}/P\lesssim 0.5\%$, at the Relativistic Heavy Ion Collider. Here I consider the possibility of employing HJET to measure the ${}^3\text{He}$ ($h$) beam polarization at the Electron-Ion Collider (EIC). The dominant contribution to the ratio of the $h^{\uparrow }p$ and $p^{\uparrow }h$ analyzing powers, which is needed for such measurements, can be easily calculated using well-known values of the proton and helion magnetic moments, but some corrections should be applied to achieve the required accuracy. It was found that corrections due to absorption and ${}^3\text{He}$ breakup effectively cancel in the ratio and a correction due to hadronic spin-flip amplitudes can be derived from the proton beam measurements. As a result, the anticipated systematic uncertainty in the measured ${}^3\text{He}$ beam polarization can satisfy the EIC requirement ${\sigma }_P^{\text{syst}}/P\lesssim 1\%$.

    hep-phPRC(2022)·7 citations
11. 11*

    Maximally entangled proton and charged hadron multiplicity in Deep Inelastic Scattering

    Martin Hentschinski🇲🇽 · Krzysztof Kutak🇵🇱 · Robert Straka🇵🇱

    We study the proposal by Kharzeev-Levin to determine entanglement entropy in Deep Inelastic Scattering (DIS) from parton distribution functions (PDFs) and to relate the former to the entropy of final state hadrons. We find several uncertainties in the current comparison to data, in particular the overall normalization, the relation between charged versus total hadron multiplicity in the comparison to experimental results as well as different methods to determine the number of partons in Deep Inelastic Scattering. We further provide a comparison to data based on leading order HERA PDF as well as PDFs obtained from an unintegrated gluon distribution subject to next-to-leading order Balitsky-Fadin-Kuraev-Lipatov and Balitsky-Kovchegov evolution. Within uncertainties we find good agreement with H1 data. We provide also predictions for entropy at lower photon virtualities, where non-linear QCD dynamics is expected to become relevant.

    hep-phhep-exEPJC(2022)·64 citations
12. 12*

    Swampland Bounds on Dark Sectors

    Miguel Montero🇺🇸 · Julian B. Muñoz🇺🇸 · Georges Obied🇺🇸

    We use Swampland principles to theoretically disfavor regions of the parameter space of dark matter and other darkly charged particles that may exist. The Festina Lente bound, the analogue of the Weak-Gravity conjecture in de Sitter, places constraints on the mass and charge of dark particles, which here we show cover regions in parameter space that are currently allowed by observations. As a consequence, a broad set of new ultra-light particles are in the Swampland, independently of their cosmic abundance, showing the complementarity of Quantum Gravity limits with laboratory and astrophysical studies. In parallel, a Swampland bound on the UV cutoff associated to the axion giving a Stückelberg photon its longitudinal mode translates to a new constraint on the kinetic mixings and masses of dark photons. This covers part of the parameter space targeted by upcoming dark-photon direct-detection experiments. Moreover, it puts astrophysically interesting models in the Swampland, including freeze-in dark matter through an ultra-light dark photon, as well as radio models invoked to explain the 21-cm EDGES anomaly.

    hep-phastro-ph.COhep-thJHEP(2022)·18 citations
13. 13*

    PanScales showers for hadron collisions: all-order validation

    Melissa van Beekveld🇬🇧 · Silvia Ferrario Ravasio🇬🇧 · Keith Hamilton🇬🇧 · Gavin P. Salam🇬🇧 · Alba Soto-Ontoso🇫🇷 · Gregory Soyez🇫🇷 · Rob Verheyen🇬🇧

    We carry out extensive tests of the next-to-leading logarithmic (NLL) accuracy of the PanScales parton showers, as introduced recently for colour-singlet production in hadron collisions. The tests include comparisons to (semi-)analytic NLL calculations of a wide range of hadron-collider observables: the colour-singlet boson transverse momentum distribution; global and non-global hadronic energy flow variables related to jet vetoes and analogues of jettiness distributions; (sub)jet multiplicities; and observables sensitive to the DGLAP evolution of the incoming momentum fractions. In the tests, we also include an implementation of a standard transverse-momentum ordered dipole shower, to establish the size of missing NLL effects in such showers, which, depending on the observable, can reach $100\%$. This paper, together with arXiv:2205.02237, constitutes the first step towards process-independent NLL-accurate parton showers for hadronic collisions.

    hep-phJHEP(2022)·65 citations
14. 14*

    $CP$ violation due to a Majorana phase in two flavor neutrino oscillations with decays

    Khushboo Dixit🇮🇳 · Akhila Kumar Pradhan🇮🇳 · S. Uma Sankar🇮🇳

    We study the conditions under which the Majorana phase of the two flavor neutrino mixing matrix appears in the oscillation probabilities and causes $CP$ violation. We find that the Majorana phase remains in the neutrino evolution equation if the neutrino decay eigenstates are not aligned with the mass eigenstates. We show that, in general, two kinds of $CP$ violation are possible: one due to the Majorana phase and the other due to the phase of the off-diagonal element of the neutrino decay matrix. We find that the $CP$ violating terms in the oscillation probabilities are also sensitive to neutrino mass ordering.

    hep-phPRD(2023)·9 citations
15. 15*

    Global 21-cm brightness temperature in viscous dark energy models

    Ashadul Halder🇮🇳 · Shashank Shekhar Pandey🇮🇳 · A. S. Majumdar🇮🇳

    We investigate the global 21-cm brightness temperature in the context of viscous dark energy (VDE) models. The bulk viscosity of dark energy perturbs the Hubble evolution of the Universe which could cool baryons faster, and hence, alter the 21-cm brightness temperature. An additional amount of entropy is also produced as an outcome of the viscous flow. We study the combined contribution of Hawking radiation from primordial black holes, decay and annihilation of particle dark matter and baryon-dark matter scattering in the backdrop of VDE models towards modification of the 21-cm temperature. We obtain bounds on the VDE model parameters which can account for the observational excess of the EDGES experiment ($-500_{-500}^{+200}$ mK at redshift $14<z<20$) due to the interplay of the above effects. Moreover, our analysis yields modified constraints on the dark matter mass and scattering cross-section compared to the case of the $\Lambda$CDM model.

    ↳ astro-ph.COhep-phJCAP(2022)·10 citations
16. 16*

    Chiral effects in astrophysics and cosmology

    Kohei Kamada🇯🇵 · Naoki Yamamoto🇯🇵 · Di-Lun Yang🇹🇼

    The microscopic quantum nature of elementary particles, chirality, leads to macroscopic phenomena like the chiral anomaly, chiral magnetic effect, and chiral plasma instability. We review recent progress of the studies of these chiral effects in high-energy astrophysics, such as pulsar kicks, magnetars, and core-collapse supernovae, and early Universe cosmology, such as the primordial magnetic field, baryogenesis, and chiral gravitational waves. We also provide a pedagogical introduction to the chiral effects and low-energy effective theories to describe them in and out of equilibrium -- the chiral (magneto)hydrodynamics, chiral kinetic theory, and chiral radiation transport theory for neutrinos.

    ↳ astro-ph.COastro-ph.HEgr-qchep-ph+1PPNP(2023)·69 citations
17. 17*

    Stringy scaling of n-point hard string scattering amplitudes

    Sheng-Hong Lai🇹🇼 · Jen-Chi Lee🇹🇼 · Yi Yang🇹🇼

    Motivated by the recent calculation of the SL(K+3,C) symmetry of n-point Lauricella string scattering amplitudes (SSA) of open bosonic string theory, we calculate ratios of the solvable infinite linear relations of arbitrary n-point hard SSA (HSSA). We discover a general stringy scaling behavior for all n-point HSSA to all string loop orders. For the special case of n=4, the stringy scaling behavior reduces to the infinite linear relations and constant ratios among HSSA conjectured by Gross [8] and later corrected and calculated by the method of decoupling of zero-norm states [11].

    ↳ hep-thhep-lathep-phmath-ph+1Eur.Phys.J.Plus(2025)·4 citations
18. 18*

    Redshift Effects in Particle Production from Kerr Primordial Black Holes

    Andrew Cheek🇵🇱 · Lucien Heurtier🇬🇧 · Yuber F. Perez-Gonzalez🇬🇧 · Jessica Turner🇬🇧

    When rotating primordial black holes evaporate via Hawking radiation, their rotational energy and mass are dissipated with different dynamics. We investigate the effect of these dynamics on the production of dark radiation -- in the form of hot gravitons or vector bosons -- and non-cold dark matter. Although the production of higher-spin particles is enhanced while primordial black holes are rotating, we show that the energy density of dark radiation experiences an extra redshift because their emission effectively halts before PBH evaporation completes. We find that taking this effect into account leads to suppression by a factor of $\mathcal{O}(10)$ of $\Delta N_{\mathrm{eff}}$ for maximally rotating black holes as compared to previous results. Using the solution of the Friedmann and Boltzmann equations to accurately calculate the evolution of linear perturbations, we revisit the warm dark matter constraints for light candidates produced by evaporation and how these limits vary over black hole spins. Due to the interplay of enhanced production and late dilution, we obtain that higher spin particles are most affected by these bounds. Our code FRISBHEE, FRIedmann Solver for Black Hole Evaporation in the Early universe, developed for this work can be found at https://github.com/yfperezg/frisbhee

    ↳ astro-ph.COhep-phPRD(2022)·60 citations
19. 19*

    Parasitic black holes: the swallowing of a fuzzy dark matter soliton

    Vitor Cardoso🇩🇰 · Taishi Ikeda🇮🇹 · Rodrigo Vicente🇪🇸 · Miguel Zilhão🇵🇹

    Fuzzy dark matter is an exciting alternative to the standard cold dark matter paradigm, reproducing its large scale predictions, while solving most of the existing tension with small scale observations. These models postulate that dark matter is constituted by light bosons and predict the condensation of a solitonic core -- also known as boson star, supported by wave pressure -- at the center of halos. However, solitons which host a \emph{parasitic} supermassive black hole are doomed to be swallowed by their guest. It is thus crucial to understand in detail the accretion process. In this work, we use numerical relativity to self-consistently solve the problem of accretion of a boson star by a central black hole, in spherical symmetry. We identify three stages in the process, a {\it boson-quake}, a {\it catastrophic stage} and a linear phase, as well as a general accurate expression for the lifetime of a boson star with an endoparasitic black hole. Lifetimes of these objects can be large enough to allow them to survive until the present time.

    ↳ gr-qcastro-ph.HEhep-phhep-thPRD(2022)·65 citations
20. 20*

    Conformal field theory for particle physicists

    Marc Gillioz🇮🇹

    This is a set of introductory lecture notes on conformal field theory. Unlike most existing reviews on the subject, CFT is presented here from the perspective of a unitary quantum field theory in Minkowski space-time. It begins with a non-perturbative formulation of quantum field theory (Wightman axioms), and then gradually focuses on the implications of scale and special conformal symmetry, all the way to the modern conformal bootstrap. This approach includes topics often left out, such as subtleties of conformal transformations in Minkowski space-time, the construction of Wightman functions and time-ordered correlators both in position- and momentum-space, unitarity bounds derived from the spectral representation, and the appearance of UV and IR divergences.

    ↳ hep-thhep-phMarc Gillioz, "Conformal Field Theory for…·17 citations
21. 21*

    Revisiting constraints on WIMPs around primordial black holes

    Estanis Utrilla Ginés🇪🇸 · Samuel J. Witte🇳🇱 · Olga Mena🇪🇸

    While Primordial Black Holes (PBHs) with masses $M_{\mathrm{PBH}}\gtrsim 10^{-11}{M}_{\odot }$ cannot comprise the entirety of dark matter, the existence of even a small population of these objects can have profound astrophysical consequences. A sub-dominant population of PBHs will efficiently accrete dark matter particles before matter-radiation equality, giving rise to high-density dark matter spikes. We consider here the scenario in which dark matter is comprised primarily of Weakly Interacting Massive Particles (WIMPs) with a small sub-dominant contribution coming from PBHs, and revisit the constraints on the annihilation of WIMPs in these spikes using observations of the isotropic gamma-ray background (IGRB) and the Cosmic Microwave Background (CMB), for a range of WIMP masses, annihilation channels, cross sections, and PBH mass functions. We find that the constraints derived using the IGRB have been significantly overestimated (in some cases by many orders of magnitude), and that limits obtained using observations of the CMB are typically stronger than, or comparable to, those coming from the IGRB. Importantly, we show that $\sim \mathcal{O}(M_{\odot })$ PBHs can still contribute significantly to the dark matter density for sufficiently low WIMP masses and p-wave annihilation cross sections.

    ↳ astro-ph.COhep-phPRD(2022)·25 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.