ShantanuT01/DACTYL-Pretraining huggingface dataset:
We conduct an analysis of the measurement abilities of distinctive LISA detector designs, examining the influence of LISA's low-frequency performance on the detection and characterization of massive black hole binaries. We are particularly interested in LISA's ability to measure massive black holes merging at frequencies near the low-frequency band edge, with masses in the range of $\sim 10^6-10^{10}M_\odot$. We examine the signal-to-noise ratio (SNR) using phenomenological waveforms for inspiral, merger, and ringdown over a wide range of massive black hole binary parameters. We employ a broad palette of possible LISA configurations with different sensitivities at low frequencies. For this analysis, we created a tool (github.com/mikekatz04/BOWIE) that evaluates the change in SNR between two parameterized situations. The shifts in SNR are computed as gains or losses as a function of binary parameters, and graphically displayed across a two dimensional grid of parameter values. We illustrate the use of this technique for both parameterized LISA mission designs, as well as for considering the influence of astrophysical parameters on gravitational wave signal models. In terms of low-frequency sensitivity, acceleration noise or armlength is found to be the most important factor in observing the largest massive black hole binaries, followed by break frequency and then spectral index. LISA's ability to probe the astrophysical population of $\sim10^7-10^9M_\odot$ black holes is greatly influenced by these aspects of its sensitivity. The importance of the constituent black hole spins is also highlighted.
The purpose of this paper is to show that the third unramified cohomology with divisible coefficients of a smooth projective geometrically rational threefold over a finite field must vanish under $\Z_{\ell}$-exactness Hard Lefschetz condition.
Recent progress in the applications of covariant density functional theory (CDFT) to the description of the spectroscopy of the heaviest nuclei is reviewed. The analysis of quasiparticle spectra in actinides and the heaviest A ~ 250 nuclei provides a measure of the accuracy of the description of single-particle energies in CDFT and an additional constraint for the choice of effective interactions for the description of superheavy nuclei. The response of these nuclei to the rotation is rather well described by cranked relativistic Hartree+Bogoliubov theory and it serves as a supplementary tool in configuration assignment in odd-mass nuclei. A systematic analysis of the fission barriers with allowance for triaxial deformation shows that covariant density functional theory is able to describe fission barriers on a level of accuracy comparable with the best phenomenological macroscopic+microscopic approaches.
We investigate whether there are attractor equations for N=1 flux vacua in generalized compactifications. We fill a gap in the existing literature by verifying analytically that the recently proposed susy attractors, for type IIB CY(3) orientifold compactifications with flux, do give supersymmetric minima of the relevant scalar potential. Furthermore, our considerations clarify various confusions about existing proposals for generalization of the flux vacua attractors to non-K\"{a}hler compactifications. We explore different possibilities for generalization and find attractor equations for N=1 Minkowski vacua only both for the heterotic string on SU(3) structure manifolds and for type IIA/B on SU(3)xSU(3) structure spaces.
Magnetic dissipation is frequently invoked as a way of powering the observed emission of relativistic flows in Gamma Ray Bursts and Active Galactic Nuclei. Pulsar Wind Nebulae provide closer to home cosmic laboratories which can be used to test the hypothesis. To this end, we analyze the observational data on the spindown power of the Crab pulsar, energetics of the Crab nebula, and its magnetic field. We show that unless the magnetic inclination angle of the Crab pulsar is very close to 90 degrees the overall magnetization of the striped wind after total dissipation of its stripes is significantly higher than that deduced in the Kennel-Coroniti model and recent axisymmetric simulations of Pulsar Wind Nebulae. On the other hand, higher wind magnetization is in conflict with the observed low magnetic field of the Crab nebula, unless it is subject to efficient dissipation inside the nebula as well. For the likely inclination angle of 45 degrees the data require magnetic dissipation on the timescale about 80 years, which is short compared to the life-time of the nebula but long compared to the time scale of Crab's gamma-ray flares.
We review the blackfold description of the fully localized orthogonal M2-M5 intersection in eleven-dimensional supergravity which constitutes the direct gravitational analogue of the Howe-Lambert-West self-dual string soliton solution. We emphasize the preliminary implications of this description for the physics of the M2-M5 system and the novel research directions that it opens. This report contains several new results. As an extension of previous work we report new results on deformations of the M2-M5-KKW intersection that describe self-dual ring intersections. Extremal non-supersymmetric configurations of this type probe novel aspects of the M2-M5 system and allow us to explore further the merits and limitations of the blackfold description of black brane intersections. In particular, we provide an example of a situation where an effective description of extremal non-supersymmetric spike configurations is shown to capture correctly features of the exact solutions beyond its strict regime of validity. This observation hints at the existence of improved convergence properties in the underlying derivative expansion scheme without the necessary presence of supersymmetry.
Exchange symmetry in acceleration partitions the configuration space of an N particle, one-dimensional, gravitational system into N! equivalent cells. We take advantage of the resulting small angular extent of each cell to construct a related integrable version of the system that takes the form of a central force problem in N-1 dimensions. The properties of the latter, including the construction of trajectories, as well as several continuum limits, are developed. Dynamical simulation is employed to compare the two models. For a class of initial conditions, excellent agreement is observed.
The Faraday dispersion function (FDF), which can be derived from an observed polarization spec- trum by Faraday rotation measure synthesis, is a profile of polarized emissions as a function of Faraday depth. We study intrinsic FDFs along sight lines through face-on, Milky-Way-like galaxies by means of a sophisticated galactic model incorporating 3D MHD turbulence, and investigate how much the FDF contains information intrinsically. Since the FDF reflects distributions of thermal and cosmic- ray electrons as well as magnetic fields, it has been expected that the FDF could be a new probe to examine internal structures of galaxies. We, however, find that an intrinsic FDF along a sight line through a galaxy is very complicated, depending significantly on actual configurations of turbulence. We perform 800 realizations of turbulence, and find no universal shape of the FDF even if we fix the global parameters of the model. We calculate the probability distribution functions of the standard deviation, skewness, and kurtosis of FDFs and compare them for models with different global pa- rameters. Our models predict that the presence of vertical magnetic fields and large scale-height of cosmic-ray electrons tend to make the standard deviation relatively large. Contrastingly, differences in skewness and kurtosis are relatively less significant.
We investigate the intersections of the curve $\mathbb{R}\ni t\mapsto \zeta({1\over 2}+it)$ with the real axis. We show unconditionally that the zeta-function takes arbitrarily large positive and negative values on the critical line.
In this paper, an improvement has been made on the variation after projection (VAP) method, which is crucial in the calculations of high-spin states. It turns out that, the form of the trial VAP wave function with spin $J$ can be simplified by adopting just one projected state rather than previously adopting all $(2J+1)$ angular momentum projected states for each selected reference state, $|\Phi\rangle$. The present calculations show that such simplification still minimizes the angular momentum projected energy up to a very good approximation. In this simplified VAP scheme, one can obtain almost equivalent VAP wave functions starting from different sets of the projected basis states. This clearly shows that a nuclear state can not be identified with a single intrinsic state, while in the traditional nuclear collective models, an intrinsic state is usually assigned to a well deformed rotational band.
The thermodynamic stability conditions (TSC) of nonadditive and composable entropies are discussed. Generally the concavity of a nonadditive entropy with respect to internal energy is not necessarily equivalent to the corresponding TSC. It is shown that both the TSC of Tsallis' entropy and that of the $\kappa$-generalized Boltzmann entropy are equivalent to the positivity of the standard heat capacity.
The H-alpha luminosity density of galaxies is used to calculate the local diffuse radiation field at the Lyman limit as resulting from star formation in the universe.   The fraction of Lyman continuum radiation leaking out from galaxies through their neutral hydrogen is the most uncertain parameter of the calculation.   A comparison of the diffuse radiation predicted from galaxies with that measured from all sources of ionization shows that the average Lyman continuum escape fraction should be lower than 1%. This number is lower than the upper limits reported so far in a few objects.   It is also shown that the luminosity density at the Lyman limit resulting from star formation is consistent with the luminosity density and the diffuse background measured in the far (non-ionizing) ultraviolet.
We give a new criterion for when a resolution of a surface of general type with canonical singularities has big cotangent bundle and a new lower bound for the values of $d$ for which there is a surface with big cotangent bundle that is deformation equivalent to a smooth hypersurface in $\mathbb{P}^3$ of degree $d$.
A new representation of the next to leading QCD corrections to the nucleon structure functions is given in terms of parton distributions. All $~\alpha_{s}~$ corrections to the leading logarithmic approximation (LLA) are included. In contrast to the similar representations in the literature terms of order $~O(\alpha_{s}^{2})~$ do not attend in our expressions for the nucleon structure functions taken in the next to leading logarithmic approximation. This result is generelized for any order in $~\alpha_{s}~$ beyond the LLA. Terms of order $~O(\alpha^{n}_{s})~$ which belong only to the approximation in consideration are present in such a representation for the structure functions.
We determined oxygen and iron abundances of the interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards Ultra luminous X-ray sources (ULXs). We determine the hydrogen column densities (n_H) towards the ULXs from XMM-Newton archival spectra of 14 ULX sources. We compare our X-ray values with those obtained from radio HI observations for 8 of the sources. The X-ray model n_H values are in good agreement with the HI n_H values, implying that the hydrogen absorption towards the ULX is not local to the source, with the exception of M81 X-1. Oxygen abundances and iron abundances are roughly solar for the host galaxies.
Considering neutrinos as time-like leptons one may estimate the three-body decay probability of muon neutrinos in long base-line accelerator experiments. In the extreme assumption of time-space symmetry the absolute value of the transcendent mass of a muon neutrino is equal to the rest mass of its bradyon partner which is, however, strongly suppressed in measurements using the weak interaction. This decay, neglecting small oscillations or other effects, leads to a strong dependence of the effect on the base-line distance. As a result, few hundred kilometre long baseline experiments might hardly see muon-like events. Total rates of electron-like events from three-body decay are calculated for K2K, MINOS and ICARUS. Shorter base-line experiments able to see clearly the effect of muon neutrino decay are very promissing component of long base-line projects.
For hybrid systems, such as molecules grafted onto solid surfaces, the calculation of linear response in time dependent density functional theory is slowed down by the need to calculate, in N^4 operations, the susceptibility of N non interacting Kohn-Sham reference electrons. We show how this susceptibility can be calculated N times faster within finite precision. By itself or in combination with previous methods, this should facilitate the calculation of TDDFT response and optical spectra of hybrid systems.
We demonstrate real-time detection of self-interfering electrons in a double quantum dot embedded in an Aharonov-Bohm interferometer, with visibility approaching unity. We use a quantum point contact as a charge detector to perform time-resolved measurements of single-electron tunneling. With increased bias voltage, the quantum point contact exerts a back-action on the interferometer leading to decoherence. We attribute this to emission of radiation from the quantum point contact, which drives non-coherent electronic transitions in the quantum dots.
We present the results of the computation of a twisting type N solution to vacuum Einstein equations following an iterative approach. Our results show that the higher order terms fail to provide a full exact solution with non-vanishing twist. Nevertheless, our fourth-order solution still represents a regular and twisting type N solution.
The pressure influence on the lattice vibration of $CaZnF_4$ has been studied by Raman diffusion up to 17 GPa. Most Raman frequencies increase with increasing pressure. Three singularities in the pressure induced frequency evolution are observed around 1.5 GPa, 10 GPa and 17 GPa. The samples pressurized to 17 GPa or higher do not revert to the ambient pressure phase after being released, the new phase showing different Raman spectra from the ordinary one. It is suggested that $CaZnF_4$ undergoes probably sudden lattice deformations at about 1.5 GPa and 10 GPa, and an irreversible phase transformation above 17 GPa.
We consider laboratory experiments that can detect stable, neutral strongly interacting massive particles (SIMPs). We explore the SIMP annihilation cross section from its minimum value (restricted by cosmological bounds) to the barn range, and vary the mass values from a GeV to a TeV. We calculate, as a function of the SIMP-nucleon cross section, the minimum nucleon number A for which there should be binding in a nucleus. We consider accelerator mass spectrometry with a gold (A=200) target, and compute the likely abundance of anomalous gold nuclei if stable neutral SIMPs exist. We also consider the prospects and problems of detecting such particles at the Tevatron. We estimate optimistically that such detection might be possible for SIMPs with SIMP-nucleon cross sections larger than 0.1 millibarn and masses between 25 and 50 GeV.
Previously derived "global" thermodynamic speed limit theorems state that increasing the maximum speed with which a system can evolve between two given probability distributions over its states requires the system to produce more entropy in its evolution. However, these theorems ignore that many systems are not monolithic, but instead comprise multiple subsystems that interact according to an (often sparse) network. Indeed, most naturally-occurring and human-engineered systems of increasing complexity can be decomposed into sets of co-evolving subsystems, where there exist a priori constraints on the dynamics of each subsystem, restricting which other subsystems can affect its dynamics. Here we derive three new SLTs that account for the thermodynamic effects of such constraints. Our first new speed limit strengthens the global speed limit. While our other two SLTs do not have this guarantee, in some situations they are even stronger than our first speed limit. Our results establish that a stochastically evolving system will, on average, produce more entropy in evolving between two distributions within a given time simply due to its comprising multiple, co-evolving subsystems. We illustrate our results with numerical calculations involving a model of two cells sensing and storing information about their environment.
Given a hyperbolic quadric of PG(5,2), there are 28 points off this quadric and 56 lines skew to it. It is shown that the $(28_6, 56_3)$-configuration formed by these points and lines is isomorphic to the combinatorial Grassmannian of type $G_2(8)$. It is also pointed out that a set of seven points of $G_2(8)$ whose labels share a mark corresponds to a Conwell heptad of PG(5,2). Gradual removal of Conwell heptads from the $(28_6, 56_3)$-configuration yields a nested sequence of binomial configurations identical with part of that found to be associated with Cayley-Dickson algebras (arXiv:1405.6888).
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations from the 2014 Long Baseline Campaign in dust continuum and spectral line emission from the HL Tau region. The continuum images at wavelengths of 2.9, 1.3, and 0.87 mm have unprecedented angular resolutions of 0.075 arcseconds (10 AU) to 0.025 arcseconds (3.5 AU), revealing an astonishing level of detail in the circumstellar disk surrounding the young solar analogue HL Tau, with a pattern of bright and dark rings observed at all wavelengths. By fitting ellipses to the most distinct rings, we measure precise values for the disk inclination (46.72pm0.05 degrees) and position angle (+138.02pm0.07 degrees). We obtain a high-fidelity image of the 1.0 mm spectral index ($\alpha$), which ranges from $\alpha\sim2.0$ in the optically-thick central peak and two brightest rings, increasing to 2.3-3.0 in the dark rings. The dark rings are not devoid of emission, we estimate a grain emissivity index of 0.8 for the innermost dark ring and lower for subsequent dark rings, consistent with some degree of grain growth and evolution. Additional clues that the rings arise from planet formation include an increase in their central offsets with radius and the presence of numerous orbital resonances. At a resolution of 35 AU, we resolve the molecular component of the disk in HCO+ (1-0) which exhibits a pattern over LSR velocities from 2-12 km/s consistent with Keplerian motion around a ~1.3 solar mass star, although complicated by absorption at low blue-shifted velocities. We also serendipitously detect and resolve the nearby protostars XZ Tau (A/B) and LkHa358 at 2.9 mm.
We consider the FCFS $\mathit{GI}/\mathit{GI}/n$ queue in the so-called Halfin-Whitt heavy traffic regime. We prove that under minor technical conditions the associated sequence of steady-state queue length distributions, normalized by $n^{1/2}$, is tight. We derive an upper bound on the large deviation exponent of the limiting steady-state queue length matching that conjectured by Gamarnik and Momcilovic [Adv. in Appl. Probab. 40 (2008) 548-577]. We also prove a matching lower bound when the arrival process is Poisson. Our main proof technique is the derivation of new and simple bounds for the FCFS $\mathit{GI}/\mathit{GI}/n$ queue. Our bounds are of a structural nature, hold for all $n$ and all times $t\geq0$, and have intuitive closed-form representations as the suprema of certain natural processes which converge weakly to Gaussian processes. We further illustrate the utility of this methodology by deriving the first nontrivial bounds for the weak limit process studied in [Ann. Appl. Probab. 19 (2009) 2211-2269].
We are concerned with the Sinh-Gordon equation in bounded domains. We construct blow up solutions with residual mass exhibiting either partial or asymmetric blow up, i.e. where both the positive and negative part of the solution blow up. This is the first result concerning residual mass for the Sinh-Gordon equation showing in particular that the concentration-compactness theory of Brezis-Merle can not be extended to this class of problems.
We report on correlations between radio luminosity and X-ray timing features in X-ray binary systems containing low magnetic field neutron stars and black holes. The sample of neutron star systems consists of 4U 1728-34, 4U 1820-34, Ser X-1, MXB 1730-335, GX 13+1, the millisecond X-ray pulsars SAX J1808.4-3658 and IGR J00291+5934, and these are compared with the black hole system GX 339-4. The analysis has been done using data from pointed observations of the Rossi X-ray Timing Explorer coordinated with radio observations. In the neutron star systems the radio luminosity L_{R} is correlated with the characteristic frequency of the L_{h} Lorentzian component detected contemporaneously in the power spectrum, and anticorrelated with its strength. Similarly, in the black hole system GX 339-4 L_{R} is correlated with the frequency of the L_{\ell} component in the power spectrum, and anti-correlated with its strength. The index of a power-law fit to the correlation is similar in both cases, L_{R} \propto \nu^{~1.4} and L_{R} \propto (rms)^{-2.3}. At lower timing frequencies, the radio luminosity is further found to be correlated with the characteristic (break) frequency of the L_{b} component of the power spectra in the neutron stars and, marginally, with the equivalent break frequency in GX 339-4. We briefly discuss the coupling between the innermost regions of the accretion disc and the production of the jet and, from the behaviour of the ms accreting X-ray pulsars, the possible role of the NS magnetic field.
In the light of the recent Planck downward revision of the electron scattering optical depth, and of the discovery of a faint AGN population at $z > 4$, we reassess the actual contribution of quasars to cosmic reionization. To this aim, we extend our previous MCMC-based data-constrained semi-analytic reionization model and study the role of quasars on global reionization history. We find that, the quasars can alone reionize the Universe only for models with very high AGN emissivities at high redshift. These models are still allowed by the recent CMB data and most of the observations related to HI reionization. However, they predict an extended and early HeII reionization ending at $z\gtrsim4$ and a much slower evolution in the mean HeII Ly-$\alpha$ forest opacity than what the actual observation suggests. Thus when we further constrain our model against the HeII Ly-$\alpha$ forest data, this AGN-dominated scenario is found to be clearly ruled out at 2-$\sigma$ limits. The data seems to favour a standard two-component picture where quasar contributions become negligible at $z\gtrsim6$ and a non-zero escape fraction of $\sim10\%$ is needed from early-epoch galaxies. For such models, mean neutral hydrogen fraction decreases to $\sim10^{-4}$ at $z=6.2$ from $\sim0.8$ at $z=10.0$ and helium becomes doubly ionized at much later time, $z\sim3$. We find that, these models are as well in good agreement with the observed thermal evolution of IGM as opposed to models with very high AGN emissivities.
This paper is lead by the question whether there is a nice structure theory of finitely generated modules over the Iwasawa algebra, i.e. the completed group algebra, R of a p-adic analytic group G. For G without any p-torsion element we prove that R is an Auslander regular ring. This result enables us to give a good definition for pseudo-null R-modules. Then the category of R-modules up to pseudo-isomorphisms is studied and we obtain a weak structure theorem for the p-primary part of a finitely generated R-module. A local duality theorem as well as the Auslander-Buchsbaum equality are further main issues. The arithmetic applications to the Iwasawa theory of abelian varieties are published elsewhere.