We discuss realization of cosmic inflation in the $\nu$-gauge mediated supersymmetry breaking scenario, in which a set of $\mathbf{24}$-dimensional chiral superfields responsible for the type III seesaw mechanism play the role of the messenger fields in gauge mediation. Using the data from neutrino oscillations, we show that the model satisfies constraints from the lepton flavor violation, perturbativity of the unified gauge couplings, the observed abundance of dark matter as well as the Higgs mass of 125.1 GeV. The predicted spectrum of the cosmic microwave background radiation fits well with the observation. We also comment on the falsifiability of this scenario by future experiments.

In this paper, we find that a magnetic transition dipole moment between tau and sterile neutrinos can account for the XENON1T excess events. Unlike the ordinary neutrino dipole moment, the introduction of the new sterile mass scale allows for astrophysical bounds to be suppressed. Interestingly, the best-fit regions that are compatible with the SN1987A imply either boron-8 as the source flux. We find that sterile neutrinos in the $\sim (500–800)\mathrm{keV}$ mass range are capable of evading astrophysical constraints while being able to successfully explain the XENON1T event rate. We also set new constraints on the dipole portal based on the Xenon 1T data. The sterile neutrino in the best fit parameter space may have significant effects on big bang nucleosynthesis (BBN). We show the region in which a low reheating temperature of the Universe may allow the BBN constraints to be alleviated.

Perturbative supersymmetry breaking on the landscape of string vacua is expected to favor large soft terms as a power-law or log distribution, but tempered by an anthropic veto of inappropriate vacua or vacua leading to too large a value for the derived weak scale, which is a violation of the atomic principle. Indeed, scans of such vacua yield a statistical prediction for light Higgs boson mass $m_h\sim 125\mathrm{GeV}$ with sparticles (save possibly light Higgsinos) typically beyond LHC reach. In contrast, models of dynamical supersymmetry (SUSY) breaking (DSB)—with a hidden sector gauge coupling $g^2$ scanned uniformly—lead to gaugino condensation and a uniform distribution of soft parameters on a log scale. Then soft terms are expected to be distributed as $m_{\mathrm{soft}}^{-1}$ favoring small values. A scan of DSB soft terms generally leads to $m_h\ll 125\mathrm{GeV}$ and sparticle masses usually below LHC limits. Thus, the DSB landscape scenario seems excluded from LHC search results. An alternative is that the exponential suppression of the weak scale is set anthropically on the landscape via the atomic principle.

We present analytical results for master integrals emerging in the computation of differential rates for inclusive weak decays of heavy flavors at next-to-leading order (NLO) in QCD. As an immediate physical application, these master integrals allow for a calculation of the spectra of the leptonic invariant mass in inclusive semileptonic decays in the framework of the heavy quark expansion, including the NLO QCD corrections to power-suppressed terms.

Quark-antiquark pair (or dijet) production at the Electron-Ion Collider has been argued to be one of the most important processes that allows access to the Weizsäcker-Williams (WW) gluon distributions in the small-$x$ limit. Within the framework of color glass condensate effective field theory, we calculate the dijet cross sections and azimuthal correlations at the partonic level by including the Sudakov resummations. Our numerical results show that the back-to-back correlations are significantly suppressed when the Sudakov resummations are taken into account. In addition, by using the solutions of the running-coupling Balitsky-Kovchegov equation, the unpolarized and linearly polarized WW gluon distributions in both coordinate and momentum space are presented.

Intense transient electric ($\mathbf{E}$) and magnetic ($\mathbf{B}$) fields are produced in the high-energy heavy-ion collisions. The electromagnetic fields produced in such high-energy heavy-ion collisions are proposed to give rise to a multitude of exciting phenomenon including the chiral magnetic effect. We use a Monte Carlo (MC) Glauber model to calculate the electric and magnetic fields, more specifically their scalar product $\mathbf{E}·\mathbf{B}$, as a function of space-time on an event-by-event basis for the $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200\mathrm{GeV}$ for different centrality classes. We also calculate the same for the isobars ruthenium and zirconium at $\sqrt{s_{NN}}=200\mathrm{GeV}$. In the QED sector, $\mathbf{E}·\mathbf{B}$ acts as a source of chiral separation effect, chiral magnetic wave, etc., which are phenomena associated to the chiral magnetic effect. We also study the relationships between the electromagnetic symmetry plane angle defined by $\mathbf{E}·\mathbf{B}$ (${\psi }_{E.B}$) and the participant plane angle ${\psi }_P$ defined from the participating nucleons for the second- to fifth-order harmonics.

Understanding various fundamental properties of nucleons and nuclei is among the most important scientific goals at the upcoming Electron-Ion Collider (EIC). With the unprecedented opportunity provided by the next-generation machine, the EIC might provide definitive answers to many standing puzzles and open questions in modern nuclear physics. We investigate one of the golden measurements proposed at the EIC, which is to obtain the spatial gluon density distribution within a lead (Pb) nucleus. The proposed experimental process is the exclusive $J/\psi$ vector-meson production off the Pb nucleus: $e+\mathrm{Pb}\to e^{\prime }+J/\psi +{\mathrm{Pb}}^{\prime }$. The Fourier transformation of the momentum transfer $|t|$ distribution of the coherent diffraction is the transverse gluon spatial distribution. In order to measure it, the experiment has to overcome an overwhelmingly large background arising from the incoherent diffractive production, where the nucleus ${\mathrm{Pb}}^{\prime }$ mostly breaks up into fragments of particles in the far-forward direction close to the hadron-going beam rapidity. We systematically study the rejection of incoherent $J/\psi$ production by vetoing products from these nuclear breakups—protons, neutrons, and photons—which is based on the BeAGLE event generator and the most up-to-date EIC Far-forward Interaction Region design. The achieved vetoing efficiency, the ratio between the numbers of vetoed events and total incoherent events, ranges from about 80% to 99% depending on $|t|$. Assuming a 5% smearing applied to the reconstructed $|t|$ resolution in the $\mathrm{Sar}t\mathrm{re}$ model, this vetoing efficiency can suppress the incoherent background to at least the first minimum of the coherent $|t|$ distribution. Experimental and accelerator machine challenges as well as potential improvements are discussed.

A semiempirical formula for the inclusive electroweak response functions in the two-nucleon emission channel is proposed. The method consists in expanding each one of the vector-vector, axial-axial, and vector-axial responses as sums of six subresponses. These correspond to separating the meson-exchange currents as the sum of three currents of similar structure and expanding the hadronic tensor as the sum of the separate contributions from each current plus the interferences between them. For each subresponse, we factorize the coupling constants, the electroweak form factors, the phase space, and the delta propagator, for the delta-forward current. The remaining spin-isospin contributions are encoded in coefficients for each value of the momentum transfer, $q$. The coefficients are fitted to the exact results in the relativistic mean field model of nuclear matter, for each value of $q$. The dependence on the energy transfer $\omega$ is well described by the semiempirical formula. The $q$-dependency of the coefficients of the subresponses can be parametrized or can be interpolated from the provided tables. The description of the five theoretical responses is quite good. The parameters of the formula, the Fermi momentum, number of particles, relativistic effective mass, vector energy, the electroweak form factors, and the coupling constants, can be modified easily. This semiempirical formula can be applied to the cross section of neutrinos, antineutrinos, and electrons.

A search for charginos and neutralinos at the Large Hadron Collider using fully hadronic final states and missing transverse momentum is reported. Pair-produced charginos or neutralinos are explored, each decaying into a high-$p_{\mathrm{T}}$ Standard Model weak boson. Fully hadronic final states are studied to exploit the advantage of the large branching ratio, and the efficient rejection of backgrounds by identifying the high-$p_{\mathrm{T}}$ bosons using large-radius jets and jet substructure information. An integrated luminosity of $139{\mathrm{fb}}^{-1}$ of proton-proton collision data collected by the ATLAS detector at a center-of-mass energy of 13 TeV is used. No significant excess is found beyond the Standard Model expectation. Exclusion limits at the 95% confidence level are set on wino or higgsino production with various assumptions about the decay branching ratios and the type of lightest supersymmetric particle. A wino (higgsino) mass up to 1060 (900) GeV is excluded when the lightest supersymmetry particle mass is below 400 (240) GeV and the mass splitting is larger than 400 (450) GeV. The sensitivity to high-mass winos and higgsinos is significantly extended relative to previous LHC searches using other final states.

A study of ${\mathrm{\Lambda }}_b^0$ baryon decays to the $Dp{K}^{-}$ final state is presented based on a proton-proton collision data sample corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ collected with the LHCb detector. Two ${\mathrm{\Lambda }}_b^0$ decays are considered, ${\mathrm{\Lambda }}_b^0\to Dp{K}^{-}$ with $D\to K^{-}{\pi }^{+}$ and $D\to K^{+}{\pi }^{-}$, where $D$ represents a superposition of $D^0$ and ${\overline{D}}^0$ states. The latter process is expected to be suppressed relative to the former, and is observed for the first time. The ratio of branching fractions of the two decays is measured, and the $CP$ asymmetry of the suppressed mode, which is sensitive to the Cabibbo-Kobayashi-Maskawa angle $\gamma$, is also reported.

We study certain infinite families of two-particle operators exchanged in 4pt correlators $⟨{\mathcal{O}}_{p_1}{\mathcal{O}}_{p_2}{\mathcal{O}}_{p_3}{\mathcal{O}}_{p_4}⟩$ of tensor multiplets living on the ${\mathrm{AdS}}_3\times S^3$ background. This is the weakly curved, weakly coupled SUGRA theory dual to the D1-D5 system with RR flux. At tree level in Mellin space, all these correlators are nicely determined by a single amplitude, which makes manifest the large $p$ limit, the connection with the flat space S-matrix, and a six dimensional conformal symmetry. We compute the $(1,1)\times \overline{(1,1)}$ superconformal blocks for the two-dimensional $\mathcal{N}=(4,4)$ conformal theory at the boundary, and then we obtain a formula for the anomalous dimensions of the two-particle operators exchanged in the symmetric and antisymmetric flavor channels. These anomalous dimensions solve a mixing problem which is analogous to the one in ${\mathrm{AdS}}_5\times S^5$ with interesting modifications. Along the way we show how the $(1,1)\times \overline{(1,1)}$ superconformal blocks relate to those in $\mathcal{N}=4$ SYM in four dimensions, and provide new intuition on the known data for ${\mathrm{AdS}}_5\times S^5$.

Unimodular gravity (UG) is an important theory which may explain the smallness of the cosmological constant. To get insight into the covariant quantization of UG, we discuss the BRST quantization of general relativity (GR) with a cosmological constant in the unimodular gauge. We develop a novel way to gauge fix the transverse diffeomorphism (TDiff) and then further to fulfill the unimodular gauge. This process requires the introduction of an additional pair of BRST doublets which decouple from the physical sector together with the other three pairs of BRST doublets for the TDiff. We show that the physical spectrum is the same as GR in the usual covariant gauge fixing. We then study a theory derived by making “Fourier transform” of GR in the unimodular gauge with respect to the cosmological constant as a candidate of “quantum UG.” We clarify the difference from GR and point out problems in this theory.

In the present paper we consider the Einstein-multiple-scalar field theory. When the target space of the scalar fields is a complete, simply connected Riemannian manifold with nonpositive sectional curvature we prove that the static and asymptotically flat solutions which possess a photon sphere are uniquely specified by their asymptotic data, i.e., by their mass, scalar charges and asymptotic values of the scalar fields. The unique solution with a photon sphere and prescribed asymptotic data is explicitly constructed.

We revisit a recent proposal for a definition of time in quantum cosmology, to investigate the effects of having more than one possible type of clock “at the same time.” We use as a test tube an extension of Einstein gravity with a massless scalar field in which the gravitational coupling $G_N$ is only a constant on-shell, mimicking the procedure for $\mathrm{\Lambda }$ in unimodular gravity. Hence we have two “simultaneous” clocks in the theory: a scalar field clock, and the conjugate of $G_N$. We find that attempts to use two coherent clocks concurrently are disastrous for recovering the classical limit. The Heisenberg relations, instead of being saturated, are always realized abundantly above their bound, with strong quantum effects expected at least in parts of the trajectory. Semiclassical states always result from situations where we effectively impose a single clock, either by making the other clock a failed clock (i.e., by choosing a state where its conjugate constant is infinitely sharp) or by choosing a basis of constants where all clocks but one are redundant; i.e., motion or change in phase space does not occur with the passing of their “times.” We show how this conclusion generalizes to fluids with any equation of state. It also applies to systems where “subclocks” of the same type could be used, for example, in mixtures of different fluids with the same equation of state.

We determine and characterize the full space of master equations describing the dynamics of perturbed Schwarzschild black holes and show that all of them are connected via Darboux transformations. This reveals the presence of a hidden symmetry, Darboux covariance, which preserves the spectrum of quasinormal modes and the continuous spectrum associated with black hole scattering processes. This picture is shown to share a deep connection with the Korteweg-de Vries equation and inverse scattering methods which leads to an infinite hierarchy of conserved quantities.

Drake and Szekeres have extended the Newman-Janis algorithm to produce stationary axisymmetric spacetimes from general static spherically symmetric solutions of the Einstein equations. The algorithm mathematically generates an energy-momentum tensor for the rotating solution, but the rotating and nonrotating system may or may not represent the same physical system, in the sense of both being a perfect fluid, or an electromagnetic field, or a $\mathrm{\Lambda }$-term, and so on. In Part I [P. Beltracchi and P. Gondolo, preceding paper, Phys. Rev. D 104, 124066 (2021)], we compared the structure of the eigenvalues and eigenvectors of the rotating and nonrotating energy-momentum tensors (their Segre types) and looked for the existence of equations of state relating the rotating energy density and principal pressures for Kerr-Schild systems. Here we extend our analysis to general static spherically symmetric systems obtained according to the Drake-Szekeres generalization of the Newman-Janis algorithm. We find that these rotating systems can have almost all Segre types except [31] and [(31)]. Moreover, the Segre type of the spacetime can change severely in passing from the nonrotating to the rotating configurations, for example to $[11Z\overline{Z}]$ from seed systems which were initially [(111,1)]. We also find conditions dictating how many equations of state may exist in a Drake-Szekeres system.

The Newman-Janis algorithm and its generalizations can be used mathematically to generate rotating solutions from nonrotating spherically-symmetric solutions within general relativity. The energy-momentum tensors of these solutions may or may not represent the same physical system, in the sense of both being a perfect fluid, or an electromagnetic field, or a $\mathrm{\Lambda }$-term, and so on. In a series of two papers, we compare the structure of the eigenvalues and eigenvectors of the rotating and nonrotating energy-momentum tensors (their Segre types) and look for the existence of equations of state relating the energy density and the principal pressures. Part I covers Kerr-Schild systems, Part II more general systems. We find that there is a unique family of stationary axisymmetric Kerr-Schild systems that obey the same equation of state in both the rotating and nonrotating configurations. This family includes the Kerr and Kerr-Newman black holes, as well as rotating spacetimes whose mass function in the nonrotating limit contains a constrained superposition of a cloud of strings term, a Reissner-Nordstrom term, a cosmological constant term, and a Schwarzschild term. We describe the common equation of state relating energy density and pressure in this family of spacetimes and discuss some of its properties.

Cosmic microwave background observations are used to constrain reheating to standard model (SM) particles after a period of inflation. As a light spectator field, the SM Higgs boson acquires large field values from its quantum fluctuations during inflation, gives masses to SM particles that vary from one Hubble patch to another, and thereby produces large density fluctuations. We consider both perturbative and resonant decay of the inflaton to SM particles. For the case of perturbative decay from coherent oscillations of the inflaton after high scale inflation, we find strong upper bounds on the reheat temperature for the inflaton decay into heavy SM particles. The strongest bounds arise in the case of reheating to top quarks where we find $T_{\mathrm{reh}}\lesssim \mathcal{O}({10}^{12})\mathrm{GeV}$ for an inflaton mass of ${10}^{13}\mathrm{GeV}$. For the case of resonant particle production (preheating) to (Higgsed) SM gauge bosons, we find temperature fluctuations larger than observed in the cosmic microwave background for a range of gauge coupling that includes those found in the SM and conclude that such preheating cannot be the main source of reheating the Universe after inflation.

We study a generalized superconformal model that gives rise to a subcritical regime of $D$-term hybrid inflation. Exhibiting the model both in a Jordan frame and in the Einstein frame, the effective potential of the subcritical regime is derived in the Einstein frame. It turns out that the inflaton-waterfall field dynamics leads to various types of inflaton potential. Consequently, the tensor-to-scalar ratio is found to range from ${10}^{-4}$ (${10}^{-3}$) to 0.1 for getting 60 (50) $e$-folds before the end of inflation.

The cosmology of a standard model gauge singlet complex scalar dark matter (DM), stabilized by a reflection symmetry, is studied, including all renormalizable interactions that preserve the reflection symmetry but can break the larger global $U(1)$ symmetry of the DM number. We find an interesting interplay of the ensuing DM self-scatterings and annihilations in generating the present DM density, and possible particle-antiparticle asymmetry in the DM sector. The role of DM self-scatterings in determining its present density and composition is a novel phenomenon. The simultaneous presence of the self-scatterings and annihilations is required to obtain a nonzero asymmetry, which otherwise vanishes due to unitarity sum rules.