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Pole skipping is a recently discovered subtle effect in the thermal energy density retarded two point function at a special point in the complex $(\omega,p)$ planes. We propose that pole skipping is determined by the stress tensor contribution to many-body chaos, and the special point is at $(\omega,p)_\text{p.s.}= i \lambda^{(T)}(1,1/u_B^{(T)})$, where $\lambda^{(T)}=2\pi/\beta$ and $u_B^{(T)}$ are the stress tensor contributions to the Lyapunov exponent and the butterfly velocity respectively. While this proposal is consistent with previous studies conducted for maximally chaotic theories, where the stress tensor dominates chaos, it clarifies that one cannot use pole skipping to extract the Lyapunov exponent of a theory, which obeys $\lambda\leq \lambda^{(T)}$. On the other hand, in a large class of strongly coupled but non-maximally chaotic theories $u_B^{(T)}$ is the true butterfly velocity and we conjecture that $u_B\leq u_B^{(T)}$ is a universal bound. While it remains a challenge to explain pole skipping in a general framework, we provide a stringent test of our proposal in the large-$q$ limit of the SYK chain, where we determine $\lambda,\, u_B,$ and the energy density two point function in closed form for all values of the coupling, interpolating between the free and maximally chaotic limits. Since such an explicit expression for a thermal correlator is one of a kind, we take the opportunity to analyze many of its properties: the coupling dependence of the diffusion constant, the dispersion relations of poles, and the convergence properties of all order hydrodynamics., Comment: 39 pages, 13 figures

In this work, we explore wormhole geometries in a recently proposed modified gravity theory arising from a non-conservative gravitational theory, tentatively denoted action-dependent Lagrangian theories. The generalized gravitational field equation essentially depends on a background four-vector $\lambda^\mu$, that plays the role of a coupling parameter associated with the dependence of the gravitational Lagrangian upon the action, and may generically depend on the spacetime coordinates. Considering wormhole configurations, by using "Buchdahl coordinates", we find that the four-vector is given by $\lambda_{\mu}=\left(0,0,\lambda_{\theta},0\right)$, and that the spacetime geometry is severely restricted by the condition $g_{tt}g_{uu}=-1$, where $u$ is the radial coordinate. We find a plethora of specific asymptotically flat, symmetric and asymmetric, solutions with power law choices for the function $\lambda$, by generalizing the Ellis-Bronnikov solutions and the recently proposed black bounce geometries, amongst others. We show that these compact objects possess a far richer geometrical structure than their general relativistic counterparts., Comment: 11 pages, 5 figures, V2: version accepted for publication in PRD

In the target fragmentation region of Semi-Inclusive Deep Inelastic Scattering, the diffractively produced hadron has small transverse momentum. If it is at order of $\Lambda_{QCD}$, it prevents to make predictions with the standard collinear factorization. However, in this case, differential cross-sections can be predicted by the factorization with fracture functions, diffractive parton distributions. If the transverse momentum is much larger than $\Lambda_{QCD}$ but much smaller than $Q$ which is the virtuality of the virtual photon, both factorizations apply. In this case, fracture functions can be factorized with collinear parton distributions and fragmentation functions. We study the factorization up to twist-3 level and obtain gauge invariant results. They will be helpful for modeling fracture functions and useful for resummation of large logarithm of the transverse momentum appearing in collinear factorization., Comment: Published version

Scalar Field Dark Matter (SFDM) comprised of ultralight ($\gtrsim 10^{-22}$ eV) bosons is an alternative to standard, collisionless Cold Dark Matter (CDM) that is CDM-like on large scales but inhibits small-scale structure formation. As a Bose-Einstein condensate, its free-field ("fuzzy") limit (FDM) suppresses structure below the de Broglie wavelength, $\lambda_\text{deB}$, creating virialized haloes with central cores of radius $\sim\lambda_\text{deB}$, surrounded by CDM-like envelopes, and a halo mass function (HMF) with a sharp cut-off on small scales. With a strong enough repulsive self-interaction (SI), structure is inhibited, instead, below the Thomas-Fermi (TF) radius, $R_\text{TF}$ (the size of an SI-pressure-supported ($n=1$)-polytrope), when $R_\text{TF} > \lambda_\text{deB}$. Previously, we developed tools to describe SFDM dynamics on scales above $\lambda_\text{deB}$ and showed that SFDM-TF haloes formed by Jeans-unstable collapse from non-cosmological initial conditions have $R_\text{TF}$-sized cores, surrounded by CDM-like envelopes. Revisiting SFDM-TF in the cosmological context, we simulate halo formation by cosmological infall and collapse, and derive its transfer function from linear perturbation theory to produce cosmological initial conditions and predict statistical measures of structure formation, such as the HMF. Since FDM and SFDM-TF transfer functions both have small-scale cut-offs, we can align them to let observational constraints on FDM proxy for SFDM-TF, finding FDM with particle masses $1 \lesssim m/(10^{-22} \text{ eV}/c^2) \lesssim 30$ corresponds to SFDM-TF with $10 \gtrsim R_\text{TF}/(1 \text{ pc}) \gtrsim 1$, favoring sub-galactic (sub-kpc) core-size. The SFDM-TF HMF cuts off gradually, however, leaving more small-mass haloes: its Jeans mass shrinks so fast, scales filtered early can still recover and grow!, Comment: 30 pages, 10 figures, accepted by MNRAS 09/22/21, comments welcome

We present a spectroscopic and photometric calibration to derive effective temperatures $T_{\mathrm{eff}}$ and metallicities [Fe/H] for M dwarfs, based on a Principal Component Analysis of 147 spectral indices measured off moderate resolution $R \sim 11\,000$), high S/N ($>100$) spectra in the $\lambda \lambda$ 8390-8834 region, plus the J$-$H color. Internal uncertainties, estimated by the residuals, are 81 K and 0.12 dex, respectively, for $T_{\mathrm{eff}}$ and [Fe/H], the calibrations being valid for 3050 K $< T_{\mathrm{eff}}, Comment: Accepted in MNRAS

We study the two-dimensional stochastic nonlinear heat equation (SNLH) and stochastic damped nonlinear wave equation (SdNLW) with an exponential nonlinearity $\lambda\beta e^{\beta u }$, forced by an additive space-time white noise. We prove local and global well-posedness of these equations, depending on the sign of $\lambda$ and the size of $\beta^2 > 0$, and invariance of the associated Gibbs measures. See the abstract of the paper for a more precise abstract. (Due to the limit on the number of characters for an abstract set by arXiv, the full abstract can not be displayed here.), Comment: 70 pages. To appear in Comm. Math. Phys. Minor typos corrected

The ensemble average of $| \sum_{j=1}^N e^{i k \lambda_j} |^2$ is of interest as a probe of quantum chaos, as is its connected part, the structure function. Plotting this average for model systems of chaotic spectra reveals what has been termed a dip-ramp-plateau shape. Generalising earlier work of Br\'ezin and Hikami for the Gaussian unitary ensemble, it is shown how the average in the case of the Laguerre unitary ensemble can be reduced to an expression involving the spectral density of the Jacobi unitary ensemble. This facilitates studying the large $N$ limit, and so quantifying the dip-ramp-plateau effect. When the parameter $a$ in the Laguerre weight $x^a e^{-x}$ scales with $N$, quantitative agreement is found with the characteristic features of this effect known for the Gaussian unitary ensemble. However, for the parameter $a$ fixed, the bulk scaled structure function is shown to have the simple functional form ${2 \over \pi} {\rm Arctan} \, k$, and so there is no ramp-plateau transition., Comment: 23 pages; v2 reference added, Introduction updated; v3 incorporates corrections and suggestions of the referees

We study the distribution of accretion rates onto supermassive black holes (SMBH) in AGNs of the local Universe ($z0.01$) in the local Universe also depends weakly on $M_\ast$ and is 0.2-1%. These results confirm the trends found in previous studies for the earlier Universe and refine the parameters of the dependence $f(\lambda_{Edd}|M_\ast)$ at $z, Comment: 16 pages, 12 figures. Published in Astronomy Letters

The nature of the three narrow $P_c$ states, i.e., $P_c(4312)$, $P_c(4440)$ and $P_c(4457)$, is under intense discussion since their discovery from the updated analysis by LHCb. In this work we extend our previous coupled-channel approach [Phys. Rev. Lett. \bf{124}, 072001 (2020)] by including the $\Lambda_c\bar{D}^{(*)}$ and $\eta_cp$ as explicitly in addition to the $J/\psi p$, as required by unitarity and heavy quark spin symmetry (HQSS). Since inelastic parameters are very badly constrained by the current data, three schemes are considered: (a) scheme I with pure contact interactions and without the $\Lambda_c\bar D^{(*)}$ interactions, (b) scheme II, where the one-pion exchange is added to scheme I, and (c) scheme III, where the $\Lambda_c \bar D^{(*)}$ are included in addition. It is shown that to obtain cutoff independent results, OPE in the multichannel system is to be supplemented with $S$-$D$ mixing contact terms. We demonstrate that the experimental data for the $J/\psi p$ invariant mass distribution are consistent with the interpretation of the $P_c(4312)$ and $P_c(4440)/P_c(4457)$ as $\Sigma_c\bar{D}$ and $\Sigma_c \bar{D}^{*}$ hadronic molecules, respectively, and that the data show clear evidence for a new narrow $P_c(4380)$, as a $\Sigma_c^*\bar D$ molecule, which should exist as a consequence of HQSS. While two equally good solutions are found in scheme I, only one of these solutions with the quantum numbers of the $P_c(4440)$ and $P_c(4457)$ being $J^P=3/2^-$ and $1/2^-$, respectively, survives the requirement of regulator independence once the OPE is included. Moreover, we predict the line shapes in the elastic and inelastic channels and demonstrate that those related to the $P_c(4440)$ and the $P_c(4457)$ in the corresponding $\Sigma_c^{(*)}\bar{D}$ and $\eta_cp$ mass distributions allow one to confirm the quantum numbers given above, once the data are available., Comment: 57 pages, 14 figures, and 13 tables

In this paper, we present a model-independent approach to calibrate the largest quasar sample. Calibrating quasar samples is essentially constraining the parameters of the linear relation between the $\log$ of the ultraviolet (UV) and X-ray luminosities. This calibration allows quasars to be used as standardized candles. There is a strong correlation between the parameters characterizing the quasar luminosity relation and the cosmological distances inferred from using quasars as standardized candles. We break this degeneracy by using Gaussian process regression to model-independently reconstruct the expansion history of the Universe from the latest type Ia supernova observations. Using the calibrated quasar dataset, we further reconstruct the expansion history up to redshift of $z\sim 7.5$. Finally, we test the consistency between the calibrated quasar sample and the standard $\rm{\Lambda}CDM$ model based on the posterior probability distribution of the GP hyperparameters. Our results show that the quasar sample is in good agreement with the standard $\rm{\Lambda}CDM$ model in the redshift range of the supernova, despite of mildly significant deviations taking place at higher redshifts. Fitting the standard $\rm{\Lambda}CDM$ model to the calibrated quasar sample, we obtain a high value of the matter density parameter $\Omega_m = 0.382^{+0.045}_{-0.042}$, which is marginally consistent with the constraints from other cosmological observations., Comment: 9 pages, 7 figures

In this paper we study on $L^2(\mathbb{R}^d)$ the quasi-periodic Schr\"odinger operator $H=-\Delta+ \lambda V(x),$ where $V$ is a real analytic quasi-periodic function and $\lambda>0$. We first show that $H$ has no eigenvalues in \textit{low energy region}. We also provide in \textit{low energy region} the new phase transition parameter, i.e. the competition between the strength of coupling and the length for frequencies., Comment: Comments welcome, a revised version, 22 pages

In the Double Pulsar, the Lense-Thirring periastron precession $\dot\omega^\mathrm{LT}$ should be measured by the end of this decade. The analyses recently appeared in the literature rely upon a formula for $\dot\omega^\mathrm{LT,\,A}$ induced by the spin angular momentum ${\boldsymbol{S}}^\mathrm{A}$ of A valid if the orbital angular momentum $\boldsymbol{L}$ and ${\boldsymbol{S}}^\mathrm{A}$ are aligned, and neglecting $\dot\omega^\mathrm{LT,\,B}$ because of the smallness of ${\boldsymbol{S}}^\mathrm{B}$. The impact on $\dot\omega^\mathrm{LT,\,A}$ of the departures of the ${\boldsymbol{S}}^\mathrm{A}$-$\boldsymbol{L}$ geometry from the ideal alignment is calculated. With the current upper bound on the misalignment angle $\delta_\mathrm{A}$ between them, the angles $\lambda_\mathrm{A},\,\eta_\mathrm{A}$ of ${\boldsymbol{S}}^\mathrm{A}$ are constrained within $85^\circ \lesssim \lambda_\mathrm{A}\lesssim 92^\circ,\, 266^\circ \lesssim \eta_\mathrm{A} \lesssim 274^\circ$. In units of $\dot\omega^\mathrm{GR}=16.89^\circ\,\mathrm{yr}^{-1}$, a range variation as little as $\Delta\dot\omega^\mathrm{LT,\,A}\doteq\dot\omega^\mathrm{LT,\,A}_\mathrm{max} - \dot\omega^\mathrm{LT,\,A}_\mathrm{min} = 8\times 10^{-8}\,\omega^\mathrm{GR}$ is implied. The experimental uncertainty $\sigma_{\dot\omega_\mathrm{obs}}$ in measuring the periastron rate with the SKA 1-mid telescope should become smaller by 2028-2030. Then, the spatial orientation of ${\boldsymbol{S}}^\mathrm{B}$ is constrained from the existing bounds on the misalignment angle $\delta_\mathrm{B}$, and $\dot\omega^\mathrm{LT,\,B}\simeq 2\times 10^{-7}\,\dot\omega^\mathrm{GR}$ is correspondingly calculated. The error $\sigma_{\dot\omega_\mathrm{obs}}$ should become smaller at the transition from MeerKAT+ facility to SKA 1-mid around 2025. (Abridged), Comment: LaTex2e, 25 pages, 6 figures, no tables. Abstract abridged to comply with the limits by Monthly Notices of the Royal Astronomical Society (MNRAS)

Wind tunnel experiments were carried out on four urban morphologies: two tall canopies with uniform-height and two super-tall canopies with a large variation in element heights (where the maximum element height is more than double the average canopy height, $h_{max}$=2.5 $h_{avg}$). {The average canopy height and packing density were fixed across the surfaces to $h_{avg} = 80$ mm, and $\lambda_{p} = 0.44$, respectively.} A combination of laser doppler anemometry and direct drag measurements were used to calculate and scale the mean velocity profiles {within the boundary layer depth, $\delta$}. In the uniform-height experiment, the high packing density resulted in a `skimming flow' regime with very little flow penetration into the canopy. This led to a surprisingly shallow roughness sublayer ($z\approx1.15h_{avg}$), and a well-defined inertial sublayer above it. {In the heterogeneous-height canopies, despite the same packing density and average height, the flow features were significantly different.} {The height heterogeneity enhanced mixing thus encouraging deep flow penetration into the canopy. A deeper roughness sublayer was found to exist and extend up to just above the tallest element height (corresponding to $z/h_{avg} = 2.85$)}, which was found to be the dominant lengthscale controlling the flow behaviour. {Results points toward the existence of an inertial sublayer for all surfaces considered herein despite the severity of the surface roughness ($\delta/h_{avg} = 3 - 6.25$)}. This contrasts with previous literature., Comment: 25 pages, 12 figures. Revised submission to Boundary-Layer Meteorology

We present the HR-pyPopStar model, which provides a complete set (in ages) of high resolution (HR) Spectral Energy Distributions of Single Stellar Populations. The model uses the most recent high wavelength-resolution theoretical atmosphere libraries for main sequence, post-AGB/planetary nebulae and Wolf-Rayet stars. The Spectral Energy Distributions are given for more than a hundred ages ranging from 0.1 Myr to 13.8 Gyr, at four different values of the metallicity (Z = 0.004, 0.008, 0.019 and 0.05), considering four different IMFs. The wavelength range goes from 91 to 24 000 {\AA} in linear steps {\delta}{\lambda} = 0.1 {\AA}, giving a theoretical resolving power R_{th,5000} ~ 50 000 at 5000 {\AA}. This is the main novelty of these spectra, unique for their age and wavelength ranges. The models include the ionising stellar populations that are relevant both at young (massive hot stars) as well as old (planetary nebulae) ages. We have tested the results with some examples of HR spectra recently observed with MEGARA at GTC. We highlight the importance of wavelength-resolution in reproducing and interpreting the observational data from the last and forthcoming generations of astronomical instruments operating at 8-10m class telescopes, with higher spectral resolution than their predecessors., Comment: 24 pages, 17 figures

Scalar Field Dark Matter (SFDM) comprised of ultralight bosons has attracted great interest as an alternative to standard, collisionless Cold Dark Matter (CDM) because of its novel structure-formation dynamics, described by the coupled Schr\"odinger-Poisson equations. In the free-field ("fuzzy") limit of SFDM (FDM), structure is inhibited below the de Broglie wavelength, but resembles CDM on larger scales. Virialized haloes have "solitonic" cores of radius $\sim\lambda_\text{deB}$, surrounded by CDM-like envelopes. When a strong enough repulsive self-interaction (SI) is also present, structure can be inhibited below a second length scale, $\lambda_\text{SI}$, with $\lambda_\text{SI}> \lambda_\text{deB}$ -- called the Thomas-Fermi (TF) regime. FDM dynamics differs from CDM because of quantum pressure, and SFDM-TF differs further by adding SI pressure. In the small-$\lambda_\text{deB}$ limit, however, we can model all three by fluid conservation equations for a compressible, $\gamma=5/3$ ideal gas, with ideal gas pressure sourced by internal velocity dispersion and, for the TF regime, an added SI pressure, $P_\text{SI}\propto \rho^2$. We use these fluid equations to simulate halo formation from gravitational collapse in 1D, spherical symmetry, demonstrating for the first time that SFDM-TF haloes form with cores the size of $R_\text{TF}$, the radius of an SI-pressure-supported $(n=1)$-polytrope, surrounded by CDM-like envelopes. In comparison with rotation curves of dwarf galaxies in the local Universe, SFDM-TF haloes pass the ["too-big-to-fail" + "cusp-core"]-test if $R_\text{TF}\gtrsim 1$ kpc., Comment: 27 pages, 11 figures, accepted by MNRAS 06/28/21, comments welcome

We investigate the properties of pole-skipping of the sound channel in which the translational symmetry is broken explicitly or spontaneously. For this purpose, we analyze, in detail, not only the holographic axion model, but also the magnetically charged black holes with two methods: the near-horizon analysis and quasi-normal mode computations. We find that the pole-skipping points are related with the chaotic properties, Lyapunov exponent ($\lambda_L$) and butterfly velocity ($v_B$), independently of the symmetry breaking patterns. We show that the diffusion constant ($D$) is bounded by $D \,\geqslant\, v_{B}^2/\lambda_{L}$, where $D$ is the energy diffusion (crystal diffusion) bound for explicit (spontaneous) symmetry breaking. We confirm that the lower bound is obtained by the pole-skipping analysis in the low temperature limit., Comment: v1: 34 pages, 23 figures; v2: 35 pages, minor edits, references added

For any compact Riemannian surface of genus three (Σ,ds2) Yang and Yau proved that the product of the first eigenvalue of the Laplacian λ1(ds2) and the area Area(ds2) is bounded above by 24π. In this paper we improve the result and we show that λ1(ds2)Area(ds2)≤16(4−√7)π≈21.668π. About the sharpness of the bound, for the hyperbolic Klein quartic surface numerical computations give the value ≈21.414π., MINECO/FEDER grants no. MTM2017-89677-P, Junta Andalucía grants no. P06-FQM-01642 and P18-FR-4049

Astronomy has always been propelled by the discovery of new phenomena lacking precedent, often followed by new theories to explain their existence and properties. In the modern era of large surveys tiling the sky at ever high precision and sampling rates, these serendipitous discoveries look set to continue, with recent examples including Boyajian's Star, Fast Radio Bursts and `Oumuamua. Accordingly, we here look ahead and aim to provide a statistical framework for interpreting such events and providing guidance to future observations, under the basic premise that the phenomenon in question stochastically repeat at some unknown, constant rate, $\lambda$. Specifically, expressions are derived for 1) the a-posteriori distribution for $\lambda$, 2) the a-posteriori distribution for the recurrence time, and, 3) the benefit-to-cost ratio of further observations relative to that of the inaugural event. Some rule-of-thumb results for each of these are found to be 1) $\lambda < \{0.7, 2.3, 4.6\}\,t_1^{-1}$ to $\{50, 90, 95\}\%$ confidence (where $t_1=$ time to obtain the first detection), 2) the recurrence time is $t_2 < \{1, 9, 99\}\,t_1$ to $\{50, 90, 95\}\%$ confidence, with a lack of repetition by time $t_2$ yielding a $p$-value of $1/[1+(t_2/t_1)]$, and, 3) follow-up for $\lesssim 10\,t_1$ is expected to be scientifically worthwhile under an array of differing assumptions about the object's intrinsic scientific value. We apply these methods to the Breakthrough Listen Candidate 1 signal and tidal disruption events observed by TESS., Comment: Accepted to MNRAS

We demonstrate that the physics which resolves naturalness problems need not take the form of new particles and can sometimes manifest itself as higher dimensional operators. As a proof of principle, we present a simple model where the scale of new particles is parametrically separated from that estimated via naturalness arguments applied to self-quartic couplings. In this example, new particles appear far above the scale $m/\sqrt{\lambda}$, where $m$ is the mass of the particle and $\lambda$ is its self-quartic coupling. The shift symmetry responsible for resolving the naturalness problem involves higher dimensional operators rather than new particles., Comment: 3 pages

We investigate entropic force cosmological models with the possibility of matter creation and energy exchange between the bulk and the horizon of a homogeneous and an isotropic flat Universe. We consider three different kinds of entropy, Bekenstein's, the non-extensive Tsallis-Cirto's and the quartic entropy, plus some phenomenological functional forms for matter creation rate to model different entropic force models and put the observational constraints on them. We show that while most of them are basically indistinguishable from a standard $\Lambda$CDM scenario, the Bekenstein entropic force model with a matter creation rate proportional to the Hubble parameter is statistically highly favored over $\Lambda$CDM. As a general result, we also find that both the Hawking temperature parameter $\gamma$, which relates the energy exchange between the bulk and the boundary of the Universe, and the matter creation rate $\Gamma(t)$, must be very small in order to reproduce observational data., Comment: 13 pages, 2 tables, 1 figure, discussion updated, new references added

We study the long-time behavior of the Schrodinger flow in a heterogeneous potential $$\lambda V$$ with small intensity $$00$$ . More precisely, the approximate normal form leads to an accurate long-time description of the Schrodinger flow as an effective unitary correction of the free flow. The approach is robust and generically applies to linear waves. For classical waves, for instance, this allows to extend diffractive geometric optics to quasiperiodically perturbed media.

The threshold behaviour of negative eigenvalues for Schr\"{o}dinger operators of the type $$ H_\lambda=-\frac{d^2}{dx^2}+U(x)+\lambda\alpha_\lambda V(\alpha_\lambda x) $$ is considered. The potentials $U$ and $V$ are real-valued bounded functions of compact support, $\lambda$ is a positive parameter, and positive sequence $\alpha_\lambda$ has a finite or infinite limit as $\lambda\to 0$. Under certain conditions on the potentials there exists a bound state of $H_\lambda$ which is absorbed at the bottom of the continuous spectrum. For several cases of the limiting behaviour of sequence $\alpha_\lambda$, asymptotic formulas for the bound states are proved and the first order terms are computed explicitly., Comment: 16 pages

Galaxy internal structure growth has long been accused of inhibiting star formation in disc galaxies. We investigate the potential physical connection between the growth of dispersion-supported stellar structures (e.g. classical bulges) and the position of galaxies on the star-forming main sequence at $z\sim0$. Combining the might of the SAMI and MaNGA galaxy surveys, we measure the $\lambda_{Re}$ spin parameter for 3781 galaxies over $9.5 < \log M_{\star} [\rm{M}_{\odot}] < 12$. At all stellar masses, galaxies at the locus of the main sequence possess $\lambda_{Re}$ values indicative of intrinsically flattened discs. However, above $\log M_{\star}[\rm{M}_{\odot}]\sim10.5$ where the main sequence starts bending, we find tantalising evidence for an increase in the number of galaxies with dispersion-supported structures, perhaps suggesting a connection between bulges and the bending of the main sequence. Moving above the main sequence, we see no evidence of any change in the typical spin parameter in galaxies once gravitationally-interacting systems are excluded from the sample. Similarly, up to 1 dex below the main sequence, $\lambda_{Re}$ remains roughly constant and only at very high stellar masses ($\log M_{\star}[\rm{M}_{\odot}]>11$), do we see a rapid decrease in $\lambda_{Re}$ once galaxies decline in star formation activity. If this trend is confirmed, it would be indicative of different quenching mechanisms acting on high- and low-mass galaxies. The results suggest that while a population of galaxies possessing some dispersion-supported structure is already present on the star-forming main sequence, further growth would be required after the galaxy has quenched to match the kinematic properties observed in passive galaxies at $z\sim0$., Comment: 16 pages, 10 figures, accepted for publication in MNRAS

To construct the rotation curve of the Galaxy, classical Cepheids with proper motions, parallaxes and line-of-sight velocities from the Gaia DR2 Catalog are used in large part. The working sample formed from literature data contains about 800 Cepheids with estimates of their age. We determined that the linear rotation velocity of the Galaxy at a solar distance is $V_0=240\pm3$~km s$^{-1}$. In this case, the distance from the Sun to the axis of rotation of the Galaxy is found to be $R_0=8.27\pm0.10$~kpc. A spectral analysis of radial and residual tangential velocities of Cepheids younger than 120 Myr showed close estimates of the parameters of the spiral density wave obtained from data both at present time and in the past. So, the value of the wavelength $\lambda_{R,\theta}$ is in the range of [2.4--3.0] kpc, the pitch angle $i_{R,\theta}$ is in the range of [$-13^\circ$,$-10^\circ$] for a four-arm pattern model, the amplitudes of the radial and tangential perturbations are $f_R\sim12$~km s$^{-1}$ and $f_\theta\sim9$~km s$^{-1}$, respectively. Velocities of Cepheids older than 120 Myr are currently giving a wavelength $\lambda_{R,\theta}\sim5$~kpc. This value differs significantly from one that we obtained from the samples of young Cepheids. An analysis of positions and velocities of old Cepheids, calculated by integrating their orbits backward in time, made it possible to determine significantly more reliable values of the parameters of the spiral density wave: wavelength $\lambda_{R,\theta}=2.7$~kpc, amplitudes of radial and tangential perturbations are $f_R=7.9$~km s$^{-1}$ and $f_\theta=5$~km s$^{-1}$, respectively., Comment: 17 pages, 12 figures, 2 tables

If $A$ is an $n \times n$ Hermitian matrix with eigenvalues $\lambda_1(A),\dots,\lambda_n(A)$ and $i,j = 1,\dots,n$, then the $j^{\mathrm{th}}$ component $v_{i,j}$ of a unit eigenvector $v_i$ associated to the eigenvalue $\lambda_i(A)$ is related to the eigenvalues $\lambda_1(M_j),\dots,\lambda_{n-1}(M_j)$ of the minor $M_j$ of $A$ formed by removing the $j^{\mathrm{th}}$ row and column by the formula $$ |v_{i,j}|^2\prod_{k=1;k\neq i}^{n}\left(\lambda_i(A)-\lambda_k(A)\right)=\prod_{k=1}^{n-1}\left(\lambda_i(A)-\lambda_k(M_j)\right)\,.$$ We refer to this identity as the \emph{eigenvector-eigenvalue identity} and show how this identity can also be used to extract the relative phases between the components of any given eigenvector. Despite the simple nature of this identity and the extremely mature state of development of linear algebra, this identity was not widely known until very recently. In this survey we describe the many times that this identity, or variants thereof, have been discovered and rediscovered in the literature (with the earliest precursor we know of appearing in 1834). We also provide a number of proofs and generalizations of the identity., Comment: 28 pages, 1 figure, phase discussion expanded, matches published version

We derive a quadratic recursion relation for the linear Hodge integrals of the form $\langle\tau_2^n\lambda_k\rangle$. These numbers are used in a formula for Masur-Veech volumes of moduli spaces of quadratic differentials discovered by Chen, M\"oller, and Sauvaget. Therefore, our recursion provides an efficient way of computing these volumes., Comment: 6 pages

Two physically important potentials (Manning-Rosen and P\"oschl-Teller) are considered for the ro-vibrational energy in diatomic molecules. An improved new approximation is invoked for the centrifugal term, which is then used for their solution within the Nikiforov-Uvarov framework. This employs a recently proposed scheme, which combines the two widely used Greene-Aldrich and Pekeris-type approximations. Thus, approximate analytical expressions are derived for eigenvalues and eigenfunctions. The energies are examined with respect to two approximation parameters, $\lambda$ and $\nu$. The original approximations are recovered for certain specials values of these two parameters. This offers a simple effective scheme for these and other relevant potentials in quantum mechanics., Comment: 16 pages, 4 figures, 2 tables

The quartic gauge boson couplings that identify the strengths of the gauge boson self-interactions are exactly determined by the non-Abelian gauge nature of the Standard Model. The examination of these couplings at $ep$ collisions with high center-of-mass energy and high integrated luminosity provides an important opportunity to test the validity of the Standard Model and the existence of new physics beyond the Standard Model. The quartic gauge boson couplings can contribute directly to multi-boson production at colliders. Therefore, we examine the potential of the process $ep \rightarrow \nu_{e}W^{+}W^{-} j$ at the Large Hadron Electron Collider and the Future Circular Collider-hadron electron to study non-standard $WWWW$ couplings in a model independent way by means of the effective Lagrangian approach. We present an investigation on measuring $W^{+}W^{-}$ production in pure leptonic and semileptonic decay channels. In addition, we calculate the sensitivity limits at $95\%$ Confidence Level on the anomalous $\frac{f_{M0}}{\Lambda^{4}}$, $\frac{f_{M1}}{\Lambda^{4}}$, $\frac{f_{M7}}{\Lambda^{4}}$, $\frac{f_{S0}}{\Lambda^{4}}$, $\frac{f_{S1}}{\Lambda^{4}}$, $\frac{f_{T0}}{\Lambda^{4}}$, $\frac{f_{T1}}{\Lambda^{4}}$ and $\frac{f_{T2}}{\Lambda^{4}}$ couplings obtained by dimension-8 operators through the process $ep \rightarrow \nu_{e}W^{+}W^{-} j$ for the Large Hadron Electron Collider and the Future Circular Hadron Electron Collider's different center-of-mass energies and integrated luminosities. Our results show that with the process $ep \rightarrow \nu_{e}W^{+}W^{-} j$ at the Large Hadron Electron Collider and the Future Circular Collider-hadron electron the sensitivity estimated on the anomalous $WWWW$ couplings can be importantly strengthened., Comment: 33 pages, 9 figures and 25 tables

We show that, if $\mathbf{W} \in \mathbb{R}^{N \times N}_{\mathsf{sym}}$ is drawn from the gaussian orthogonal ensemble, then with high probability the degree 4 sum-of-squares relaxation cannot certify an upper bound on the objective $N^{-1} \cdot \mathbf{x}^\top \mathbf{W} \mathbf{x}$ under the constraints $x_i^2 - 1 = 0$ (i.e. $\mathbf{x} \in \{ \pm 1 \}^N$) that is asymptotically smaller than $\lambda_{\max}(\mathbf{W}) \approx 2$. We also conjecture a proof technique for lower bounds against sum-of-squares relaxations of any degree held constant as $N \to \infty$, by proposing an approximate pseudomoment construction., Comment: 34 pages. Minor text revisions; closest to published version to appear in Mathematical Programming

Dust-obscured galaxies (DOGs) with extreme infrared luminosities may represent a key phase in the co-evolution of galaxies and supermassive black holes. We select 12 DOGs at $0.3\lesssim z\lesssim1.0$ with broad Mg II or H$\beta$ emission lines and investigate their X-ray properties utilizing snapshot observations ($\sim3~\mathrm{ks}$ per source) with Chandra. By assuming that the broad lines are broadened due to virial motions of broad-line regions, we find that our sources generally have high Eddington ratios ($\lambda_\mathrm{Edd}$). Our sources generally have moderate intrinsic X-ray luminosities ($L_\mathrm{X}\lesssim10^{45}~\mathrm{erg~s^{-1}}$), which are similar to those of other DOGs, but are more obscured. They also present moderate outflows and intense starbursts. Based on these findings, we conclude that high-$\lambda_\mathrm{Edd}$ DOGs are closer to the peaks of both host-galaxy and black-hole growth compared to other DOGs, and that AGN feedback has not swept away their reservoirs of gas. However, we cannot fully rule out the possibility that the broad lines are broadened by outflows, at least for some sources. We investigate the relations among $L_\mathrm{X}$, AGN rest-frame $6~\mathrm{\mu m}$ monochromatic luminosity, and AGN bolometric luminosity, and find the relations are consistent with the expected ones., Comment: 19 pages, 14 figures, accepted for publication in MNRAS

We study the distribution of line-of-sight velocities of galaxies in the vicinity of SDSS redMaPPer galaxy clusters. Based on their velocities, galaxies can be split into two categories: galaxies that are dynamically associated with the cluster, and random line-of-sight projections. Both the fraction of galaxies associated with the galaxy clusters, and the velocity dispersion of the same, exhibit a sharp feature as a function of radius. The feature occurs at a radial scale $R_{\rm edge} \approx 2.2R_{\rm{\lambda}}$, where $R_{\rm{\lambda}}$ is the cluster radius assigned by redMaPPer. We refer to $R_{\rm edge}$ as the "edge radius." These results are naturally explained by a model that further splits the galaxies dynamically associated with a galaxy cluster into a component of galaxies orbiting the halo and an infalling galaxy component. The edge radius $R_{\rm edge}$ constitutes a true "cluster edge", in the sense that no orbiting structures exist past this radius. A companion paper (Aung et al. 2020) tests whether the "halo edge" hypothesis holds when investigating the full three-dimensional phase space distribution of dark matter substructures in numerical simulations, and demonstrates that this radius coincides with a suitably defined splashback radius., Comment: 10 pages, 5 figures, submitted to MNRAS, companion paper to Aung et al. 2020

We study the effect of an explicit interaction between two scalar fields components describing dark matter in the context of a recent proposal framework for interaction. We find that, even assuming a very small coupling, it is sufficient to explain the observational effects of a cosmological constant, and also overcome the problems of the $\Lambda$CDM model without assuming an exotic dark energy., Comment: 11 pages, 6 figures. arXiv admin note: text overlap with arXiv:1507.03800 by other authors

An important task at future colliders is the measurement of the triple Higgs coupling. Depending on its size relative to the Standard Model (SM) value, certain collider options result in a higher experimental accuracy. Within the framework of Two Higgs Doublet Models (2HDM) types I and II we investigate the allowed ranges for all triple Higgs couplings involving at least one light, SM-like Higgs boson. We take into account theoretical constraints (unitarity, stability), experimental constraints from direct Higgs-boson searches, measurements of the SM-like Higgs-boson properties, flavor observables and electroweak precision data. We find that the SM-type triple Higgs coupling w.r.t. its SM value, λhhh/λSM, can range between ∼−0.5 and ∼1.5. Depending on which value is realized, the HL-LHC can compete with, or is clearly inferior to the ILC. We find the coupling λhhH between ∼−1.5 and ∼1.5. Triple Higgs couplings involving two heavy Higgs bosons, λhHH, λhAA and λhH+H− can reach values up to O(10), roughly independent of the 2HDM type. This can lead to potentially strongly enhanced production of two Higgs-bosons at the HL-LHC or high-energy e+e− colliders., The present work has received financial support from the ‘Spanish Agencia Estatal de Investigación” (AEI) and the EU “Fondo Europeo de Desarrollo Regional” (FEDER) through the project FPA2016-78022-P and from the grant IFT Centro de Excelencia Severo Ochoa SEV-2016-0597. The work of S.H. was also supported in part by the MEINCOP Spain under contract FPA2016-78022-P and in part by the “Spanish Red Consolider MultiDark” FPA2017-90566-REDC. This work has also received partial funding/support from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 674896. The work of F.A. was also supported by the Spanish Ministry of Science and Innovation via a FPU grant with code FPU18/06634., Funded by SCOAP3.

We have started an ambitious program to determine if the full diversity of extinction laws is real or if some of it is due to calibration or methodological issues. Here we start by analyzing the information on NIR extinction in a 2MASS stellar sample with good quality photometry and very red colours. We calculate the extinction at 1 $\mu$m, $A_1$, and the power-law exponent, $\alpha$ ($A_\lambda = A_1 \lambda^{-\alpha}$), for the 2MASS stars located in the extinction trajectory in the $H-K$ vs. $J-H$ plane expected for red giants with $A_1 > 5$ mag. We test the validity of the assumption about the nature of those stars, whether a single or multiple values of $\alpha$ are needed, and the spatial variations of the results. Most ($\sim$83%) of those stars can indeed be explained by high-extinction red giants and the rest is composed of extinguished AGB stars (mostly O-rich), blended sources, and smaller numbers of other objects, a contaminant fraction that can be reduced with the help of Gaia} DR2 data. Galactic red giants experience a NIR extinction with $\alpha\sim 2.27$ and an uncertainty of a few hundredths of a magnitude. There is no significant spread in $\alpha$ even though our sample is widely distributed and has a broad range of extinctions. Differences with previous results are ascribed to the treatment of non-linear photometric effects and/or the contaminant correction. Future research should concentrate in finding the correct functional form for the NIR extinction law. In the appendix we detail the treatment of non-linear photometric effects in the 2MASS bands., Comment: 13 pages, accepted for publication in MNRAS

We study a class of close-packed dimer models on the square lattice, in the presence of small but extensive perturbations that make them non-determinantal. Examples include the 6-vertex model close to the free-fermion point, and the dimer model with plaquette interaction previously analyzed in \cite{A,AL,GMT17a,GMT17b}. By tuning the edge weights, we can impose a non-zero average tilt for the height function, so that the considered models are in general not symmetric under discrete rotations and reflections. In the determinantal case, height fluctuations in the massless (or `liquid') phase scale to a Gaussian log-correlated field and their amplitude is a universal constant, independent of the tilt. When the perturbation strength $\lambda$ is sufficiently small we prove, by fermionic constructive Renormalization Group methods, that log-correlations survive, with amplitude $A$ that, generically, depends non-trivially and non-universally on $\lambda$ and on the tilt. On the other hand, $A$ satisfies a universal scaling relation (`Haldane' or `Kadanoff' relation), saying that it equals the anomalous exponent of the dimer-dimer correlation., Comment: 78 pages, 5 figures. Version accepted for publication on Comm. Math. Phys. Compared to previous version, a few more details have been added in Sect.6.5 on the finite size corrections to the correlation functions, see in particular eqs.(6.132), (6.133) and following discussion

In the {\Lambda}-CDM paradigm of cosmology, anisotropies larger than 260 Mpc shouldn't exist. However, the existence of the Hercules-Corona Borealis Great Wall (HCB) is purported to challenge this principle by some with an estimated size exceeding 2000 Mpc. Recently, some have challenged the assertion of the existence of the HCB, attributing the anisotropy to sky exposure effects. It has never been explained why the original methods purporting the existence of the HCB produce anisotropies, even if sky-exposure effects are taken into account. In this paper, I apply the methods of the original papers purporting the existence of the HCB in various Monte-Carlo simulations that assume isotropy to analyze the empirical meaning of the significance levels of the original tests used. I find that, although the statistical tests at first glance show significant anisotropies present in the suspect sample, Monte-Carlo simulations can easily reproduce the sample in most cases, and if not, the differences can be accounted for by other statistical considerations. An updated sample raises the probability of drawing the observed clustering from an isotropic sample ten-fold in some cases. Thus the statistical tests used in prior studies overestimate the significance of the observed anisotropy, and an updated sample returns even less significant probabilities. Given the ability to reproduce the observed anisotropy in Monte-Carlo simulations, the new, higher probabilities of being drawn from isotropy for an updated sample, and the work of previous papers attributing anisotropies to sky-selection effects, the existence of the HCB must be treated as doubtful at best., Comment: 6 pages, 5 figures. Accepted for publication in MNRAS

In this article, a detailed parameter extraction methodology is proposed for low-frequency noise (LFN) in single-layer (SL) graphene transistors (GFETs) based on a recently established compact LFN model. The drain current and LFN of two short channel back-gated GFETs ( ${L} = {300}$ and 100 nm) were measured at lower and higher drain voltages, for a wide range of gate voltages covering the region away from charge neutrality point (CNP) up to CNP at p-type operation region. Current–voltage ( IV ) and LFN data were also available from a long-channel SL top solution-gated (SG) GFET ( ${L} = {5}\,\,\mu \text{m}$ ), for both p- and n-type regions near and away CNP. At each of these regimes, the appropriate IV and LFN parameters can be accurately extracted. Regarding LFN, mobility fluctuation effect is dominant at CNP, and from there, the Hooge parameter $\alpha _{H}$ can be extracted, whereas the carrier number fluctuation contribution which is responsible for the well-known M-shape bias dependence of output noise divided by squared drain current, also observed in our data, makes possible the extraction of the ${N}_{T}$ parameter related to the number of traps. In the less possible case of a $\Lambda $ -shape trend, ${N}_{T}$ and $\alpha _{H}$ can be extracted simultaneously from the region near CNP. Away from CNP, contact resistance can have a significant contribution to LFN, and from there, the relevant parameter ${S}_{\Delta {R}}^{{2}}$ is defined. The LFN parameters described above can be estimated from the low drain voltage region of operation where the effect of velocity saturation (VS) mechanism is negligible. VS effect results in the reduction of LFN at higher drain voltages, and from there, the IV parameter $h\Omega $ which represents the phonon energy and is related to VS effect can be derived both from drain current and LFN data.

Requiring the existence of a unitary, causal and local UV-completion places a set of positivity bounds on the corresponding effective field theories (EFTs). We discuss the obstructions and possibility in applying the positivity bound to cosmology, in particular the EFT of cosmological perturbations. Taking a $c_T=1$ beyond-Horndeski EFT as an illustrative example, we derive such bounds, which incorporate the cosmological correction of order $H^2/\Lambda^2$, $\Lambda$ being the cutoff scale. The derived bounds are applied to slow-roll inflation with beyond Horndeski operators. It is found that the cosmological positivity bounds may be either stronger or weaker than their flat space counterpart., Comment: 24 pages, 2 figures; major revision; matched published version in EPJC

The classical spectral curve for the worldsheet theory of the AdS_5 x S^5 lambda superstring is constructed. The lambda string is interpreted as a regularized, non-abelian T dual of the AdS_5 x S^5 superstring with respect to full PSU(2,2|4) symmetry. The form of the curve is identified as the semi-classical limit of a set of Bethe ansatz equations for an XXZ type spin chain for the supergroup PSU(2,2|4) in contrast to the string in AdS_5 x S^5 which is XXX type., 45 pages, numerous improvements, version accepted for publication

We studied the spectral features of Si II $\lambda\lambda$4130, 5972, 6355 and S II W-trough for a large sample of Type Ia supernovae (SNe Ia). We find that in NV (Normal-Velocity) subclass of SNe Ia, these features tend to reach a maximum line strength near maximum light, except for Si II $\lambda$5972. Spectral features with higher excitation energy, such as S II W-trough, are relatively weak and have relatively low velocity. SNe Ia with larger $\Delta$m$_{15}$($B$) tend to have lower velocities especially at phases after maximum light. NV SNe show a trend of increasing line strength with increasing $\Delta$m$_{15}$($B$), while 91T/99aa-like SNe show an opposite trend. Near maximum light, the absorption depth of Si II $\lambda$5972 shows the strongest correlation with $\Delta$m$_{15}$($B$), while at early times the sum of the depths of Si II $\lambda\lambda$4130 and 5972 shows the strongest correlation with $\Delta$m$_{15}$($B$). The overall correlation between velocity and line strength is positive, but within NV SNe the correlation is negative or unrelated. In normal SNe Ia, the velocity-difference and depth-ratio of a longer-wavelength feature to a shorter-wavelength feature tend to increase with increasing $\Delta$m$_{15}$($B$). These results are mostly well explained with atomic physics, but some puzzles remain, possibly related to the effects of the saturation, line competition or other factors., Comment: 14 pages, 13 figures. Accepted for publication in MNRAS

We present here medium resolution (\lambda /\Delta\lambda\sim1200) H- and K-band spectra of M type dwarf stars covering the wavelength range 1.50 - 1.80 {\mu}m and 1.95 - 2.45 {\mu}m. The sample includes 53 dwarf stars (M0V-M7V) from new observations using the TIFR Near-Infrared Spectrometer and Imager (TIRSPEC) instrument on the 2-m Himalayan Chandra Telescope (HCT). Using interferometrically-measured effective temperature (T_{eff}), radius and luminosity of nearby bright calibrator stars, we have created new empirical relationships among those fundamental parameters and spectral indices. The equivalent widths of H-band spectral features like Mg (1.57 {\mu}m), Al (1.67 {\mu}m) and Mg (1.71 {\mu}m), and the H_{2}O-H index are found to be good indicators of T_{eff}, radius and luminosity and we establish the linear functions using these features relating to those stellar parameters. The root mean squared error (RMSE) of our best fits are 102K, 0.027R_{\sun} and 0.12dex respectively. Using spectral type standards along with known parallaxes, we calibrate both H and K-band H_{2}O indices as a tracer of spectral type and absolute K_{s} magnitude. Metallicities of M-dwarf samples are estimated using the K-band calibration relationships. The mass of M-dwarfs could be determined using the luminosity (L/L_{\sun}) and we establish a new empirical relation for this. We also compare and contrast our results with other similar work from the literature., Comment: 19 pages, 12 figures, accepted on February 08, 2020 for publication in Monthly Notices of the Royal Astronomical Society (MNRAS)

We consider the 3D Schr\"odinger operator $H_0$ with constant magnetic field $B$ of scalar intensity $b>0$, and its perturbations $H_+$ (resp., $H_-$) obtained by imposing Dirichlet (resp., Neumann) conditions on the boundary of the bounded domain $\Omega_{\rm in} \subset {\mathbb R}^3$. We introduce the Krein spectral shift functions $\xi(E;H_\pm,H_0)$, $E \geq 0$, for the operator pairs $(H_\pm,H_0)$, and study their singularities at the Landau levels $\Lambda_q : = b(2q+1)$, $q \in {\mathbb Z}_+$, which play the role of thresholds in the spectrum of $H_0$. We show that $\xi(E;H_+,H_0)$ remains bounded as $E \uparrow \Lambda_q$, $q \in {\mathbb Z}_+$ being fixed, and obtain three asymptotic terms of $\xi(E;H_-,H_0)$ as $E \uparrow \Lambda_q$, and of $\xi(E;H_\pm,H_0)$ as $E \downarrow \Lambda_q$. The first two terms are independent of the perturbation while the third one involves the {\em logarithmic capacity} of the projection of $\Omega_{\rm in}$ onto the plane perpendicular to $B$., Comment: 35 pages

Data on hadron multiplicities from inelastic proton-proton interactions in the energy range of the NICA collider have been compiled. The compilation includes recent results from the NA61/SHINE and NA49 experiments at the CERN SPS accelerator. New parameterizations for excitation functions of mean multiplicities $\left$, $\left$, $\left$, $\left$, $\left$, $\left$ are obtained in the region of collision energies $3, Comment: Submitted to PEPAN Letters

Previous work has shown that total variation superiorization (TVS) improves reconstructed image quality in proton computed tomography (pCT). The structure of the TVS algorithm has evolved since then and this paper investigated if this new algorithmic structure provides additional benefits to pCT image quality. Structural and parametric changes introduced to the original TVS algorithm included: (1) inclusion or exclusion of TV reduction requirement, (2) a variable number, $N$ , of TV perturbation steps per feasibility-seeking iteration, and (3) introduction of a perturbation kernel $0 . The structural change of excluding the TV reduction requirement check tended to have a beneficial effect for $3\le N\le 6$ and allows full parallelization of the TVS algorithm. Repeated perturbations per feasibility-seeking iterations reduced total variation (TV) and material dependent standard deviations for $3\le N\le 6$ . The perturbation kernel $\alpha $ , effectively equal to $\alpha =0.5$ in the original TVS algorithm, reduced TV and standard deviations as $\alpha $ was increased beyond $\alpha =0.5$ , but negatively impacted reconstructed relative stopping power (RSP) values for $\alpha >0.75$ . The reductions in TV and standard deviations allowed feasibility-seeking with a larger relaxation parameter $\lambda $ than previously used, without the corresponding increases in standard deviations experienced with the original TVS algorithm. This paper demonstrates that the modifications related to the evolution of the original TVS algorithm provide benefits in terms of both pCT image quality and computational efficiency for appropriately chosen parameter values.

A new ro-vibrational line list for the ground electronic state of the main isotopologue of acetylene, 12C2H2, is computed as part of the ExoMol project. The aCeTY line list covers the transition wavenumbers up to 10 000 cm−1 (λ > 1 $\mu$m), with lower and upper energy levels up to 12 000 and 22 000 cm−1 considered, respectively. The calculations are performed up to a maximum value for the vibrational angular momentum, Kmax = Lmax = 16, and maximum rotational angular momentum, J = 99. Higher values of J were not within the specified wavenumber window. The aCeTY line list is considered to be complete up to 2200 K, making it suitable for use in characterizing high-temperature exoplanet or cool stellar atmospheres. Einstein-A coefficients, which can directly be used to calculate intensities at a particular temperature, are computed for 4.3 billion (4 347 381 911) transitions between 5 million (5 160 803) energy levels. We make comparisons against other available data for 12C2H2, and demonstrate this to be the most complete line list available. The line list is available in electronic form from the online CDS and ExoMol data bases.

Funder: Physics Division, National Center for Theoretical Sciences; doi: http://dx.doi.org/10.13039/100009638, We study a special running vacuum model (RVM) with $$\Lambda = 3 \alpha H^2+3\beta H_0^4 H^{-2}+\Lambda _0$$Λ=3αH2+3βH04H-2+Λ0, where $$\alpha $$α, $$\beta $$β and $$\Lambda _0$$Λ0 are the model parameters and H is the Hubble one. This RVM has non-analytic background solutions for the energy densities of matter and radiation, which can only be evaluated numerically. From the analysis of the CMB power spectrum and baryon acoustic oscillation along with the prior of $$\alpha >0$$α>0 to avoid having a negative dark energy density, we find that $$\alpha

Programmable metasurfaces have garnered significant attention as they confer unprecedented control over the electromagnetic (EM) response of any surface. Such feature has given rise to novel design paradigms such as Software-Defined Metamaterials (SDM) and Reconfigurable Intelligent Surfaces (RIS) with multiple groundbreaking applications. However, the development of programmable metasurfaces tailored to the particularities of a potentially large application pool becomes a daunting task because the design space becomes remarkably large. This paper aims to ease the design process by proposing a methodology that employs a semi-analytical formulation to model the response of a metasurface and, then, derives performance scaling trends as functions of a representative set of design and application-specific variables. Although the methodology is amenable to any EM functionality, this paper explores its use for the case of beam steering at 26 GHz for 5G applications. Conventional beam steering metrics are evaluated as functions of the unit cell size, number of unit cell states, and metasurface size for different incidence and reflection angles. It is shown that metasurfaces 5¿×5¿ or larger with unit cells of ¿/3 and four unit cell states ensure good performance overall. Further, it is demonstrated that performance degrades significantly for angles larger than ¿>60o and that, to combat this, extra effort is needed in the development of the unit cell. These performance trends, when combined with power and cost models, will pave the way to optimal metasurface dimensioning. This work was supported in part by the European Commission (VISORSURF) under Grant H2020-FETOPEN-736876, and in part by Catalan Institution for Research and Advanced Studies (ICREA) through the ICREA Academia Programme. Odysseas Tsilipakos acknowledges support by the Stavros Niarchos Foundation within the framework of the project Advancing Young Researchers Human Capital in Cutting Edge Technologies in the Preservation of Cultural Heritage and the Tackling of Societal Challenges (ARCHERS).

Improving our understanding of the nuclear properties of high-Eddington-ratio (λEdd) active galactic nuclei (AGN) is necessary since at this regime the radiation pressure is expected to affect the structure and efficiency of the accretion disc-corona system. This may cause departures from the typical nuclear properties of low-λEdd AGN, which have been largely studied so far. We present here the X-ray spectral analysis of 14 radio-quiet, λEdd ≳ 1 AGN at 0.4 ≤ z ≤ 0.75, observed with XMM-Newton. Optical/UV data from simultaneous Optical Monitor observations have also been considered. These quasars were selected to have relatively high values of black hole mass (MBH ∼ 108 − 8.5 M⊙) and bolometric luminosity (Lbol ∼ 1046 erg s−1) in order to complement previous studies of high-λEdd AGN at lower MBH and Lbol. We studied the relation between λEdd and other key X-ray spectral parameters, such as the photon index (Γ) of the power-law continuum, the X-ray bolometric correction (kbol, X), and the optical/UV-to-X-ray spectral index (αox). Our analysis reveals that, despite the homogeneous optical and supermassive black hole accretion properties, the X-ray properties of these high-λEdd AGN are quite heterogeneous. We indeed measured values of Γ between 1.3 and 2.5, at odds with the expectations based on previously reported Γ − λEdd relations, for which Γ ≥ 2 would be a ubiquitous hallmark of AGN with λEdd ∼ 1. Interestingly, we found that ∼30% of the sources are X-ray weak, with an X-ray emission about a factor of ∼10 − 80 fainter than that of typical AGN at similar UV luminosities. The X-ray weakness seems to be intrinsic and not due to the presence of absorption along the line of sight to the nucleus. This result may indicate that high-λEdd AGN commonly undergo periods of intrinsic X-ray weakness. Furthermore, results from follow-up monitoring with Swift of one of these X-ray weak sources suggest that these periods can last for several years. © ESO 2022., This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. Part of this work is based on archival data, software and online services provided by the Space Science Data Center – ASI. This work has been partially supported by the ASI-INAF program I/004/11/4. ML acknowledges financial support from the PhD programme in Astronomy, Astrophysics and Space Science supported by MIUR (Ministero dell’Istruzione, dell’Università e della Ricerca). EP, LZ, FT, SB, AL and GV acknowledge financial support under ASI/INAF contract 2017-14-H.0. EP, SB, MB and GV acknowledge support from PRIN MIUR project “Black Hole winds and the Baryon Life Cycle of Galaxies: the stone-guest at the galaxy evolution supper”, contract #2017PH3WAT. AdO acknowledges financial support from the State Agency for Research of the Spanish MCIU through the project PID2019-106027GB-C41 and the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709). RM acknowledges the financial support of INAF (Istituto Nazionale di Astrofisica), Osservatorio Astronomico di Roma, ASI (Agenzia Spaziale Italiana) under contract to INAF: ASI 2014-049-R.0 dedicated to SSDC. CR acknowledges support from the Fondecyt Iniciacion grant 11190831.

We propose to investigate the effects of new physics in the semi-leptonic sequential decay $\Lambda_b \to \Lambda_c (\to \Lambda \pi) \tau{\bar \nu}_{\tau}$. Firstly, we write the general, model independent, non-covariant expression of the differential decay width of the process. Then, we calculate that observable according to three different types of new physics interactions, which might explain the tension of data with the standard model predictions. We find that some coefficients of the differential decay width are sensitive to the kind of interaction that is assumed. The measurements that we suggest seem to be feasible., Comment: 10 pages

Laminar premixed flame profiles of methane/air free flames and strained flames at different fuel/air ratios and strain rates are analysed using detailed chemistry with Lewis numbers equal to one. It is shown that the detailed chemistry flame profiles of progress variables CO2+CO and H2O+H2 in canonically stretched coordinates can be fitted accurately by a slight generalization of recently proposed analytical presumed flame profiles over a wide range of fuel/air ratios through adaptation of a single model parameter. Strained flame profiles can be reproduced using an additional linear coordinate transformation, emulating the compression of the preheat zone by strain as predicted by premixed flame theory. The model parameter can alternatively be determined using only the laminar flame speeds and the fully burnt temperatures from the laminar flame calculations. The stretch factor of the coordinate transformation is proportional to cp/lambda, which drops by factor up to 4 across the laminar flame. It is shown how the non-constant cp/lambda modifies the laminar flame \textcolor{black}{probability density function (pdf)}, a polynomial fit to cp/lambda as function of progress variable allows analytical results for the laminar flame pdf, the mean value of progress variable and of the reaction source term. An analytic pdf for partially premixed flames is proposed based on Bayes theorem as a combination of a beta pdf for the mixture fraction and the laminar flame pdf's evaluated at the respective fuel/air ratio., 32 pages, 20 figures