Search results for "binary [neutron star]"
showing 10 items of 544 documents
Dynamical environments of relativistic binaries: The phenomenon of resonance shifting
2019
In this article, we explore both numerically and analytically how the dynamical environments of mildly relativistic binaries evolve with increasing the general relativity factor $\gamma$ (the normalized inverse of the binary size measured in the units of the gravitational radius corresponding to the total mass of the system). Analytically, we reveal a phenomenon of the relativistic shifting of mean-motion resonances: on increasing $\gamma$, the resonances between the test particle and the central binary shift, due to the relativistic variation of the mean motions of the primary and secondary binaries and the relativistic advance of the tertiary's pericenter. To exhibit the circumbinary dyna…
Global Coastal Permeability database (GCPdb)
2023
The Global Coastal Permeability Database contains both the input and output data of the Global Coastal Permeability Model developed by Tschaikowski et al. (2023) and available at DOI: 10.5281/zenodo.7845568. The model is implemented in R and calculates the coastal permeability for each shoreline segment of the global shoreline vector created by Sayre et al. (2019) with a 30-meter resolution and covering a spatial extent of 180.0°W to 180.0°E longitude and 60.8°S to 83.7°N latitude. The coastline is separated into three sections (A: coastal aquifer section, B: shoreline section, C: shallow section), and permeability values and ranges are provided for each section. Permeability values were de…
Post-post-Newtonian effects on a clean nearly-Newtonian binary
1983
Etude du taux de changement temporel moyen de l'energie newtonienne et du moment d'une binaire presque newtonienne, ponctuelle. On trouve qu'il faut ajouter quelques termes post-post newtoniens non seculaires aux flux radiatifs seculaires standards. Les termes post-post newtoniens tendent vers zero pour l'observateur du centre de masse newtonien dans le cas de l'energie mais pas dans le cas du moment. Du fait de la longue periode de ces termes ils sont observationnellement significatifs, c'est-a-dire qu'ils vont apparaitre comme s'ils etaient des effets seculaires
A trace partitioned Gray code forq-ary generalized Fibonacci strings
2015
AbstractWe provide a trace partitioned Gray code for the set of q-ary strings avoiding a pattern constituted by k consecutive equal symbols. The definition of this Gray code is based on two different constructions, according to the parity of q. This result generalizes, and is based on, a Gray code for binary strings avoiding k consecutive 0's.
Identifying Images with Ladders Using Deep CNN Transfer Learning
2019
Deep Convolutional Neural Networks (CNNs) as well as transfer learning using their pre-trained models often find applications in image classification tasks. In this paper, we explore the utilization of pre-trained CNNs for identifying images containing ladders. We target a particular use case, where an insurance firm, in order to decide the price for workers’ compensation insurance for its client companies, would like to assess the risk involved in their workplace environments. For this, the workplace images provided by the client companies can be utilized and the presence of ladders in such images can be considered as a workplace hazard and therefore an indicator of risk. To this end, we e…
Solvent Effects on Vapor–Liquid Equilibria of the Binary System 1-Hexene + n-Hexane
2012
In order to study the separation of 1-hexene and n-hexane, two solvents, 2-pentanol and ethyl-butyrate, are tested as possible entrainers for an extractive distillation. In this way, isobaric vapor–liquid equilibrium (VLE) data at 100 kPa have been measured for the two ternary systems formed by the initial mixture and one of the mentioned solvents: 1-hexene + n-hexane + ethyl butyrate and 1-hexene + n-hexane + 2-pentanol. VLE data for the four constituent binary systems have also been measured. These systems are 1-hexene + ethyl butyrate, n-hexane + ethyl butyrate, 1-hexene + 2-pentanol, and finally n-hexane + 2-pentanol. All binary systems show moderate positive deviations from the ideal b…
On Sets of Words of Rank Two
2019
Given a (finite or infinite) subset X of the free monoid A∗ over a finite alphabet A, the rank of X is the minimal cardinality of a set F such that X⊆ F∗. A submonoid M generated by k elements of A∗ is k-maximal if there does not exist another submonoid generated by at most k words containing M. We call a set X⊆ A∗ primitive if it is the basis of a |X|-maximal submonoid. This extends the notion of primitive word: indeed, w is a primitive set if and only if w is a primitive word. By definition, for any set X, there exists a primitive set Y such that X⊆ Y∗. The set Y is therefore called a primitive root of X. As a main result, we prove that if a set has rank 2, then it has a unique primitive …
Constant circulation sequences of binary neutron stars and their spin characterization
2018
For isentropic fluids, dynamical evolution of a binary system conserves the baryonic mass and circulation; therefore, sequences of constant rest mass and constant circulation are of particular importance. In this work, we present the extension of our Compact Object CALculator (\cocal{}) code to compute such quasiequilibria and compare them with the well-known corotating and irrotational sequences, the latter being the simplest, zero-circulation case. The circulation as a measure of the spin for a neutron star in a binary system has the advantage of being exactly calculable since it is a local quantity. To assess the different measures of spin, such as the angular velocity of the star, the q…
Correlated optical/X-ray variability in the high-mass X-ray binary SAX J2103.5+4545
2009
SAX J2103.5+4545 is the Be/X-ray binary with the shortest orbital period. It shows extended bright and faint X-ray states that last for a few hundred days. The main objective of this work is to investigate the relationship between the X-ray and optical variability and to characterise the spectral and timing properties of the bright and faint states. We have found a correlation between the spectral and temporal parameters that fit the energy and power spectra. Softer energy spectra correspond to softer power spectra. That is to say, when the energy spectrum is soft the power at high frequencies is suppressed. We also present the results of our monitoring of the Halpha line of the optical cou…
Completion of the universal I-Love-Q relations in compact stars including the mass
2017
In a recent paper we applied a rigorous perturbed matching framework to show the amendment of the mass of rotating stars in Hartle's model. Here, we apply this framework to the tidal problem in binary systems. Our approach fully accounts for the correction to the Love numbers needed to obtain the universal $I$-Love-$Q$ relations. We compute the corrected mass vs radius configurations of rotating quark stars, revisiting a classical paper on the subject. These corrections allow us to find a universal relation involving the second-order contribution to the mass $\delta M$. We thus complete the set of universal relations for the tidal problem in binary systems, involving four perturbation param…