Extending previous work by a number of authors, we have recently presented a new approach in which the detection of gravitational waves from merging neutron star binaries can be used to determine the equation of state of matter at nuclear density and hence the structure of neutron stars. In particular, after performing a large number of numerical-relativity simulations of binaries with nuclear equations of state, we have found that the post-merger emission is characterized by two distinct and robust spectral features. While the high-frequency peak was already shown to be associated with the oscillations of the hypermassive neutron star produced by the merger and to depend on the equation of state, we have highlighted that the low-frequency peak is related to the merger process and to the total compactness of the stars in the binary. This relation is essentially universal and provides a powerful tool to set tight constraints on the equation of state. We here provide additional information on the extensive analysis performed, illustrating the methods used, the tests considered, as well as the robustness of the results. We also discuss additional relations that can be deduced when exploring the data and how these correlate with various properties of the binary. Finally, we present a simple mechanical toy model that explains the main spectral features of the post-merger signal and can even reproduce analytically the complex waveforms emitted right after the merger.

We measure the cross-correlation of cosmic microwave background (CMB) lensing convergence maps derived from Atacama Cosmology Telescope data with galaxy lensing convergence maps as measured by the Canada-France-Hawaii Telescope Stripe 82 Survey. The CMB-galaxy lensing cross power spectrum is measured for the first time with a significance of $4.2\sigma$, which corresponds to a 12% constraint on the amplitude of density fluctuations at redshifts $\sim 0.9$. With upcoming improved lensing data, this novel type of measurement will become a powerful cosmological probe, providing a precise measurement of the mass distribution at intermediate redshifts and serving as a calibrator for systematic biases in weak lensing measurements.

In this paper, we compute the soft-virtual corrections to Higgs boson production in gluon fusion for infinite top-quark mass at next-to-next-to-next-to-leading order in QCD. In addition, we present analogous soft-virtual terms for both Drell-Yan lepton production in QCD and scalar pair production in $\mathcal{N}=4$ super Yang-Mills theory. The result for Drell-Yan lepton production is derived from the result for Higgs boson production using Casimir scaling arguments together with well-known results available in the literature. For scalar pair production in the $\mathcal{N}=4$ model, we show by explicit calculation that the result is equal to the part of the Higgs boson soft-virtual term which is of maximal transcendentality weight.

We present the first hybrid measurement of the average muon number in air showers at ultrahigh energies, initiated by cosmic rays with zenith angles between 62° and 80°. The measurement is based on 174 hybrid events recorded simultaneously with the surface detector array and the fluorescence detector of the Pierre Auger Observatory. The muon number for each shower is derived by scaling a simulated reference profile of the lateral muon density distribution at the ground until it fits the data. A ${10}^{19}\mathrm{eV}$ shower with a zenith angle of 67°, which arrives at the surface detector array at an altitude of 1450 m above sea level, contains on average $(2.68\pm 0.04\pm 0.48(\text{sys}))\times {10}^7$ muons with energies larger than 0.3 GeV. The logarithmic gain $\mathrm{d}\ln N_{\mu }/\mathrm{d}\ln E$ of muons with increasing energy between $4\times {10}^{18}\mathrm{eV}$ and $5\times {10}^{19}\mathrm{eV}$ is measured to be $(1.029\pm 0.024\pm 0.030(\text{sys}))$.

In the first part of this article I determine the geometry of a slowly rotating black hole deformed by generic tidal forces created by a remote distribution of matter. The metric of the deformed black hole is obtained by integrating the Einstein field equations in a vacuum region of spacetime bounded by $r<r_{\max }$, with $r_{\max }$ a maximum radius taken to be much smaller than the distance to the remote matter. The tidal forces are assumed to be weak and to vary slowly in time, and the metric is expressed in terms of generic tidal quadrupole moments ${\mathcal{E}}_{ab}$ and ${\mathcal{B}}_{ab}$ that characterize the tidal environment. The metric incorporates couplings between the black hole’s spin vector and the tidal moments, and captures all effects associated with the dragging of inertial frames. In the second part of the article I determine the tidal moments by immersing the black hole in a larger post-Newtonian system that includes an external distribution of matter; while the black hole’s internal gravity is allowed to be strong, the mutual gravity between the black hole and the external matter is assumed to be weak. The post-Newtonian metric that describes the entire system is valid when $r>r_{\min }$, where $r_{\min }$ is a minimum distance that must be much larger than the black hole’s radius. The black-hole and post-Newtonian metrics provide alternative descriptions of the same gravitational field in an overlap $r_{\min }<r<r_{\max }$, and matching the metrics determine the tidal moments, which are expressed as post-Newtonian expansions carried out through one-and-a-half post-Newtonian order. Explicit expressions are obtained in the specific case in which the black hole is a member of a post-Newtonian two-body system.

The tension between the best fit parameters derived by the Planck team and a number of other astronomical measurements suggests either systematics in the astronomical measurements, systematics in the Planck data, the need for new physics, or a combination thereof. We reanalyze the Planck data and find that the $217\mathrm{GHz}\times 217\mathrm{GHz}$ detector set spectrum used in the Planck analysis is responsible for some of this tension. We use a map-based foreground cleaning procedure, relying on a combination of 353 GHz and 545 GHz maps to reduce residual foregrounds in the intermediate frequency maps used for cosmological inference. For our baseline data analysis, which uses 47% of the sky and makes use of both 353 and 545 GHz data for foreground cleaning, we find the $\mathrm{\Lambda }\mathrm{CDM}$ cosmological parameters ${\mathrm{\Omega }}_c{h}^2=0.1170\pm 0.0025$, $n_s=0.9686\pm 0.0069$, $H_0=68.0\pm 1.1\mathrm{km}{\mathrm{s}}^{-1}{\mathrm{Mpc}}^{-1}$, ${\mathrm{\Omega }}_b{h}^2=0.02197\pm 0.00026$, $\ln {10}^{10}{A}_s=3.082\pm 0.025$, and $\tau =0.090\pm 0.013$. While in broad agreement with the results reported by the Planck team, these revised parameters imply a universe with a lower matter density of ${\mathrm{\Omega }}_m=0.302\pm 0.015$, and parameter values generally more consistent with pre-Planck CMB analyses and astronomical observations. We compare our cleaning procedure with the foreground modeling used by the Planck team and find good agreement. The difference in parameters between our analysis and that of the Planck team is mostly due to our use of cross-spectra from the publicly available survey maps instead of their use of the detector set cross-spectra which include pixels only observed in one of the surveys. We show evidence suggesting residual systematics in the detector set spectra used in the Planck likelihood code, which is substantially reduced for our spectra. Using our cleaned survey cross-spectra, we recompute the limit on neutrino species and find $N_{\mathrm{eff}}=3.34\pm 0.35$. We also recompute limits on the $n_s-r$ plane, and neutrino mass constraints.

Over the past decades, several ideas and technologies have been developed to directly detect weakly interacting massive particles (WIMP) from the galactic halo. All these detection strategies share the common goal of discriminating a WIMP signal from the residual backgrounds. By directly detecting WIMPs, one can measure some or all of the observables associated to each nuclear recoil candidates, such as their energy and direction. In this study, we compare and examine the discovery potentials of each readout strategies from counting only (bubble chambers) to directional detectors (Time Projection Chambers) with 1d-, 2d-, and 3d-sensitivity. Using a profile likelihood analysis, we show that, in the case of a large and irreducible background contamination characterized by an energy distribution similar to the expected WIMP signal, directional information can improve the sensitivity of the experiment by several orders of magnitude. We also found that 1d directional detection is only less effective than a full 3d directional sensitivity by about a factor of 3, or 10 if we assume no sense recognition, still improving by a factor of 2 or more if only the energy of the events is being measured.

A simple way of explaining dark matter without modifying known Standard Model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. We consider a hidden sector containing two stable particles charged under an unbroken $U(1{)}^{\prime }$ gauge symmetry, hence featuring dissipative interactions. The massless gauge field associated with this symmetry, the dark photon, can interact via kinetic mixing with the ordinary photon. In fact, such an interaction of strength $\epsilon \sim {10}^{-9}$ appears to be necessary in order to explain galactic structure. We calculate the effect of this new physics on big bang nucleosynthesis and its contribution to the relativistic energy density at hydrogen recombination. We then examine the process of dark recombination, during which neutral dark states are formed, which is important for large-scale structure formation. Galactic structure is considered next, focusing on spiral and irregular galaxies. For these galaxies we modeled the dark matter halo (at the current epoch) as a dissipative plasma of dark matter particles, where the energy lost due to dissipation is compensated by the energy produced from ordinary supernovae (the core-collapse energy is transferred to the hidden sector via kinetic mixing induced processes in the supernova core). We find that such a dynamical halo model can reproduce several observed features of disk galaxies, including the cored density profile and the Tully-Fisher relation. We also discuss how elliptical and dwarf spheroidal galaxies could fit into this picture. Finally, these analyses are combined to set bounds on the parameter space of our model, which can serve as a guideline for future experimental searches.

The effective actions of gauge bosons, fermions, and scalars, which are obtained within the hard-loop approximation, are shown to have unique forms for a whole class of gauge theories including QED, scalar QED, super QED, pure Yang-Mills, QCD, and super Yang-Mills. The universality occurs irrespective of a field content of each theory and of a variety of specific interactions. Consequently, the long-wavelength or semiclassical features of plasma systems governed by these theories such as collective excitations are almost identical. An origin of the universality, which holds within the limits of applicability of the hard-loop approach, is discussed.

We present an exact solution to the Boltzmann equation which describes a system undergoing boost-invariant longitudinal and azimuthally symmetric radial expansion for arbitrary shear viscosity to entropy density ratio. This new solution is constructed by considering the conformal map between Minkowski space and the direct product of three-dimensional de Sitter space with a line. The resulting solution respects $SO(3{)}_q\otimes SO(1,1)\otimes Z_2$ symmetry. We compare the exact kinetic solution with exact solutions of the corresponding macroscopic equations that were obtained from the kinetic theory in ideal and second-order viscous hydrodynamic approximations. The macroscopic solutions are obtained in de Sitter space and are subject to the same symmetries used to obtain the exact kinetic solution.

Understanding the relation between underlying matter distribution and biased tracers such as galaxies or dark matter halos is essential to extract cosmological information from ongoing or future galaxy redshift surveys. At sufficiently large scales such as the baryon acoustic oscillation (BAO) scale, a standard approach for the bias problem on the basis of the perturbation theory (PT) is to assume the “local bias” model in which the density field of biased tracers is deterministically expanded in terms of matter density field at the same position. The higher-order bias parameters are then determined by combining the power spectrum with higher-order statistics such as the bispectrum. As is pointed out by recent studies, however, nonlinear gravitational evolution naturally induces nonlocal bias terms even if initially starting only with purely local bias. As a matter of fact, previous works showed that the second-order nonlocal bias term, which corresponds to the gravitational tidal field, is important to explain the characteristic scale-dependence of the bispectrum. In this paper we extend the nonlocal bias term up to third order, and investigate whether the PT-based model including nonlocal bias terms can simultaneously explain the power spectrum and the bispectrum of simulated halos in $N$-body simulations. The bias renormalization procedure ensures that only one additional term is necessary to be introduced to the power spectrum as a next-to-leading order correction, even if third-order nonlocal bias terms are taken into account. We show that the power spectrum, including density and momentum, and the bispectrum between halo and matter in $N$-body simulations can be simultaneously well explained by the model including up to third-order nonlocal bias terms at $k\lesssim 0.1h/\mathrm{Mpc}$. Also, the results are in a good agreement with theoretical predictions of a simple coevolution picture, although the agreement is not perfect. These trend can be found for a wide range of halo mass, $0.7\lesssim M_{\text{halo}}[10^{13}{M}_{\odot }/h]\lesssim 20$ at various redshifts, $0\le z\le 1$. These demonstrations clearly show a failure of the local bias model even at such large scales, and we conclude that nonlocal bias terms should be consistently included in order to accurately model statistics of halos.

We present a unifying theme relating BPS partition functions and superconformal indices. In the case with complex supersymmetry central charges (as in $\mathcal{N}=2$ in $d=4$ and $\mathcal{N}=(2,2)$ in $d=2$), the known results can be reinterpreted as the statement that the BPS partition functions can be used to compute a specialization of the superconformal indices. We argue that in the case with real central charge in the supersymmetry algebra, as in $\mathcal{N}=1$ in $d=5$ (or the $\mathcal{N}=2$ in $d=3$), the BPS degeneracy captures the full superconformal index. Furthermore, we argue that refined topological strings, which capture five-dimensional (5d) BPS degeneracies of M theory on Calabi-Yau 3-folds, can be used to compute a 5d supersymmetric index including in the sectors with three-dimensional defects for a large class of 5d superconformal theories. Moreover, we provide evidence that distinct Calabi–Yau singularities which are expected to lead to the same Superconformal field theory yield the same index.

We calculate the masses of baryons containing one, two, or three heavy quarks using lattice QCD. We consider all possible combinations of charm and bottom quarks, and compute a total of 36 different states with $J^P={\frac{1}{2}}^{+}$ and $J^P={\frac{3}{2}}^{+}$. We use domain-wall fermions for the up, down, and strange quarks, a relativistic heavy-quark action for the charm quarks, and nonrelativistic QCD for the bottom quarks. Our analysis includes results from two different lattice spacings and seven different pion masses. We perform extrapolations of the baryon masses to the continuum limit and to the physical pion mass using $\mathrm{SU}(4|2)$ heavy-hadron chiral perturbation theory including $1/m_Q$ and finite-volume effects. For the 14 singly heavy baryons that have already been observed, our results agree with the experimental values within the uncertainties. We compare our predictions for the hitherto unobserved states with other lattice calculations and quark-model studies.

The massless Gross-Neveu and chiral Gross-Neveu models are well known examples of integrable quantum field theories in $1+1$ dimensions. We address the question of whether integrability is preserved if one either replaces the four-fermion interaction in fermion-antifermion channels by a dual interaction in fermion-fermion channels, or if one adds such a dual interaction to an existing integrable model. The relativistic Hartree-Fock-Bogoliubov approach is adequate to deal with the large-$N$ limit of such models. In this way, we construct and solve three integrable models with Cooper pairing. We also identify a candidate for a fourth integrable model with maximal kinematic symmetry, the “perfect” Gross-Neveu model. This type of field theories can serve as exactly solvable toy models for color superconductivity in quantum chromodynamics.

We extend the notion of general coordinate invariance to many-body, not necessarily relativistic, systems. As an application, we investigate nonrelativistic general covariance in Galilei-invariant systems. The peculiar transformation rules for the background metric and gauge fields, first introduced by Son and Wingate in 2005 and refined in subsequent works, follow naturally from our framework. Our approach makes it clear that Galilei or Poincaré symmetry is by no means a necessary prerequisite for making the theory invariant under coordinate diffeomorphisms. General covariance merely expresses the freedom to choose spacetime coordinates at will, whereas the true, physical symmetries of the system can be separately implemented as “internal” symmetries within the vielbein formalism. A systematic way to implement such symmetries is provided by the coset construction. We illustrate this point by applying our formalism to nonrelativistic $s$-wave superfluids.

We propose methods and present calculations that can be used to search for evidence of cosmic fields by investigating the parity-violating effects, including parity nonconservation amplitudes and electric dipole moments, that they induce in atoms. The results are used to constrain important fundamental parameters describing the strength of the interaction of various cosmic fields with electrons, protons, and neutrons. Candidates for such fields are dark matter (including axions) and dark energy, as well as several more exotic sources described by standard-model extensions. Calculations of the effects induced by pseudoscalar and pseudovector fields are performed for H, Li, Na, K, Cu, Rb, Ag, Cs, Ba, ${\mathrm{Ba}}^{+}$, Dy, Yb, Au, Tl, Fr, and ${\mathrm{Ra}}^{+}$. Existing parity nonconservation experiments in Cs, Dy, Yb, and Tl are combined with these calculations to directly place limits on the interaction strength between the temporal component, $b_0$, of a static pseudovector cosmic field and the atomic electrons, with the most stringent limit of $|b_0^e|<7\times {10}^{-15}\mathrm{GeV}$, in the laboratory frame of reference, coming from Dy. From a measurement of the nuclear anapole moment of Cs, and a limit on its value for Tl, we also extract limits on the interaction strength between the temporal component of this cosmic field, as well as a related tensor cosmic-field component $d_{00}$, with protons and neutrons. The most stringent limits of $|b_0^p|<4\times {10}^{-8}\mathrm{GeV}$ and $|d_{00}^p|<5\times {10}^{-8}$ for protons and $|b_0^n|<2\times {10}^{-7}\mathrm{GeV}$ and $|d_{00}^n|<2\times {10}^{-7}$ for neutrons (in the laboratory frame) come from the results using Cs. Axions may induce oscillating parity- and time reversal-violating effects in atoms and molecules through the generation of oscillating nuclear magnetic quadrupole and Schiff moments, which arise from $P$- and $T$-odd intranuclear forces and from the electric dipole moments of constituent nucleons. Nuclear spin-independent parity nonconservation effects may be enhanced in diatomic molecules possessing close pairs of opposite-parity levels in the presence of time-dependent interactions.

Many theories beyond the Standard Model contain hidden photons. A light hidden photon will generically couple to the Standard Model through a kinetic mixing term, giving a powerful avenue for detection using “light-shining-through-a-wall”-type transmission experiments with resonant cavities. We demonstrate a parametric enhancement of the signal in such experiments, resulting from transmission of the longitudinal mode of the hidden photon. While previous literature has focused on the production and detection of transverse modes, the longitudinal mode allows a significant improvement in experimental sensitivity. Although optical experiments such as ALPS are unable to take useful advantage of this enhancement, the reach of existing microwave cavity experiments such as CROWS is significantly enhanced beyond their published results. Future microwave cavity experiments, designed with appropriate geometry to take full advantage of the longitudinal mode, will provide a powerful probe of hidden-photon parameter space extending many orders of magnitude beyond current limits, including significant regions where the hidden photon can be dark matter.

Galactic cosmic-ray (CR) transport parameters are usually constrained by the boron-to-carbon ratio. This procedure is generically plagued with degeneracies between the diffusion coefficient and the vertical extent of the Galactic magnetic halo. The latter is of paramount importance for indirect dark matter (DM) searches because it fixes the amount of DM annihilation or decay that contributes to the local antimatter CR flux. These degeneracies could be broken by using secondary radioactive species, but the current data still have large error bars, and this method is extremely sensitive to the very local interstellar medium properties. Here, we propose to use the low-energy CR positrons in the GeV range as another direct constraint on diffusion models. We show that the PAMELA data disfavor small diffusion halo ($L\lesssim 3\mathrm{kpc}$) and large diffusion slope models and exclude the minimal configuration [Maurin et al. Astrophys. J. 555, 585 (2001); Donato et al. Phys. Rev. D 69, 063501 (2004)] widely used in the literature to bracket the uncertainties in the DM signal predictions. This is complementary to indirect constraints (diffuse radio and gamma-ray emissions) and has a strong impact on DM searches. Indeed, this makes the antiproton constraints more robust while enhancing the discovery/exclusion potential of current and future experiments, like AMS-02 and GAPS, especially in the antiproton and antideuteron channels.

We have searched for proton decay via $p\to \nu K^{+}$ using Super-Kamiokande data from April 1996 to February 2013, $260\mathrm{kiloton}·\mathrm{year}$ exposure in total. No evidence for this proton decay mode is found. A lower limit of the proton lifetime is set to $\tau /B(p\to \nu K^{+})>5.9\times 10^{33}$ years at 90% confidence level.

The resonant substructure of $B_s^0\to {\overline{D}}^0{K}^{-}{\pi }^{+}$ decays is studied with the Dalitz plot analysis technique. The study is based on a data sample corresponding to an integrated luminosity of $3.0{\mathrm{fb}}^{-1}$ of $pp$ collision data recorded by LHCb. A structure at $m({\overline{D}}^0{K}^{-})\approx 2.86\mathrm{GeV}/c^2$ is found to be an admixture of spin-1 and spin-3 resonances. The masses and widths of these states and of the $D_{s2}^{*}(2573{)}^{-}$ meson are measured, as are the complex amplitudes and fit fractions for all the ${\overline{D}}^0{K}^{-}$ and $K^{-}{\pi }^{+}$ components included in the amplitude model. In addition, the $D_{s2}^{*}(2573{)}^{-}$ resonance is confirmed to be spin 2.