Results for "Tomaž Pisanski"

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A novel characterization of cubic Hamiltonian graphs via the associated quartic graphsAug 08 2015We give a necessary and sufficient condition for a cubic graph to be Hamiltonian by analyzing Eulerian tours in certain spanning subgraphs of the quartic graph associated with the cubic graph by 1-factor contraction. This correspondence is most useful ... More
Characterization of generalized Petersen graphs that are Kronecker coversFeb 20 2018The family of generalized Petersen graphs $G(n, k)$, introduced by Coxeter et al. [4] and named by Mark Watkins (1969), is a family of cubic graphs formed by connecting the vertices of a regular polygon to the corresponding vertices of a star polygon. ... More
Coronoids, Patches and Generalised AltansSep 29 2015In this paper we revisit coronoids, in particular multiple coronoids. We consider a mathematical formalisation of the theory of coronoid hydrocarbons that is solely based on incidence between hexagons of the infinite hexagonal grid in the plane. In parallel, ... More
Strong Traces Model of Self-Assembly Polypeptide StructuresJul 25 2013A novel self-assembly strategy for polypeptide nanostructure design was presented in [Design of a single-chain polypeptide tetrahedron assembled from coiled-coil segments, Nature Chemical Biology 9 (2013) 362--366]. The first mathematical model (polypeptide ... More
Vertex-transitive Haar graphs that are not Cayley graphsMar 18 2016In a recent paper (arXiv:1505.01475 ) Est\'elyi and Pisanski raised a question whether there exist vertex-transitive Haar graphs that are not Cayley graphs. In this note we construct an infinite family of trivalent Haar graphs that are vertex-transitive ... More
Medial symmetry type graphsJan 31 2013A $k$-orbit map is a map with its automorphism group partitioning the set of flags into $k$ orbits. Recently $k$-orbit maps were studied by Orbani\' c, Pellicer and Weiss, for $k \leq 4$. In this paper we use symmetry type graphs to extend such study ... More
The number of cyclic configurations of type $(v_3)$ and the isomorphism problemJan 11 2013A configuration of points and lines is cyclic if it has an automorphism which permutes its points in a full cycle. A closed formula is derived for the number of non-isomorphic connected cyclic configurations of type (v_3), i.e., which have v points and ... More
The Sierpiński product of graphsApr 08 2019In this paper we introduce a product-like operation that generalizes the construction of generalized Sierpi\'nski graphs. Let $G,H$ be graphs and let $f: V(G) \to V(H)$ be a function. Then the Sierpi\'nski product of $G$ and $H$ with respect to $f$ is ... More
Splittable and unsplittable graphs and configurationsMar 17 2018We prove that there exist infinitely many splittable and also infinitely many unsplittable cyclic $(n_3)$ configurations. We also present a complete study of trivalent cyclic Haar graphs on at most 60 vertices with respect to splittability. Finally, we ... More
Point-ellipse and some other exotic configurationsMar 14 2019In this paper we introduce point-ellipse configurations and point-conic configurations. We study some of their basic properties and describe two interesting families of balanced point-ellipse, respectively point-conic $6$-configurations. The construction ... More
Core-Free, Rank Two Coset Geometries from Edge-Transitive Bipartite GraphsJun 28 2011Jun 29 2011It is known that the Levi graph of any rank two coset geometry is an edge-transitive graph, and thus coset geometries can be used to construct many edge transitive graphs. In this paper, we consider the reverse direction. Starting from edge- transitive ... More
GI-graphs and their groupsJul 11 2012The class of generalized Petersen graphs was introduced by Coxeter in the 1950s. Frucht, Graver and Watkins determined the automorphism groups of generalized Petersen graphs in 1971, and much later, Nedela and \v{S}koviera and (independently) Lovre\v{c}i\v{c}-Sara\v{z}in ... More
Which Haar graphs are Cayley graphs?May 06 2015For a finite group $G$ and subset $S$ of $G,$ the Haar graph $H(G,S)$ is a bipartite regular graph, defined as a regular $G$-cover of a dipole with $|S|$ parallel arcs labelled by elements of $S$. If $G$ is an abelian group, then $H(G,S)$ is well-known ... More
Kronecker covers, V-construction, unit-distance graphs and isometric point-circle configurationsJun 24 2012Jul 29 2012We call a polytope P of dimension 3 admissible if it has the following two properties: (1) for each vertex of P the set of its first-neighbours is coplanar; (2) all planes determined by the first-neighbours are distinct. It is shown that the Levi graph ... More
Iterated altans and their propertiesApr 30 2015Recently a class of molecular graphs, called altans, became a focus of attention of several theoretical chemists and mathematicians. In this paper we study primary iterated altans and show, among other things, their connections with nanotubes and nanocaps. ... More
Danzer's configuration revisitedJan 06 2013Jan 06 2015We revisit the configuration of Danzer DCD(4), a great inspiration for our work. This configuration of type (35_4) falls into an infinite series of geometric point-line configurations DCD(n). Each DCD(n) is characterized combinatorially by having the ... More
Vertex-transitive graphs and their arc-typesMay 08 2015Let $X$ be a finite vertex-transitive graph of valency $d$, and let $A$ be the full automorphism group of $X$. Then the arc-type of $X$ is defined in terms of the sizes of the orbits of the action of the stabiliser $A_v$ of a given vertex $v$ on the set ... More
On the Number of Hamiltonian GroupsMar 09 2005Finite hamiltonian groups are counted. The sequence of numbers of all groups of order $n$ all whose subgroups are normal and the sequence of numbers of all groups of order less or equal to $n$ all whose subgroups are normal are presented.
Combinatorial configurations, quasiline arrangements, and systems of curves on surfacesOct 09 2014It is well known that not every combinatorial configuration admits a geometric realization with points and lines. Moreover, some of them do not even admit realizations with pseudoline arrangements, i.e., they are not topological. In this paper we provide ... More
Distance-residual graphsSep 28 2006If we are given a connected finite graph $G$ and a subset of its vertices $V_{0}$, we define a distance-residual graph as a graph induced on the set of vertices that have the maximal distance from $V_{0}$. Some properties and examples of distance-residual ... More
Multiple Kronecker Covering GraphsMay 08 2005A graph may be the Kronecker cover in more than one way. In this note we explore this phenomenon. Using this approach we show that the least common cover of two graphs need not be unique.
Sizes of Pentagonal Clusters in FullerenesMar 16 2017Stability and chemistry, both exohedral and endohedral, of fullerenes are critically dependent on the distribution of their obligatory 12 pentagonal faces. It is well known that there are infinitely many IPR-fullerenes and that the pentagons in these ... More
Combinatorial algorithm for counting small induced graphs and orbitsJan 25 2016Graphlet analysis is an approach to network analysis that is particularly popular in bioinformatics. We show how to set up a system of linear equations that relate the orbit counts and can be used in an algorithm that is significantly faster than the ... More
Heat transport in quantum harmonic chains with Redfield bathsMar 09 2012Mar 16 2012We provide an explicit method for solving general markovian master equations for quadratic bosonic Hamiltonians with linear bath operators. As an example we consider a one-dimensional quantum harmonic oscillator chain coupled to thermal reservoirs at ... More
Determinantal representations of smooth cubic surfacesJun 05 2006Mar 22 2007For every smooth (irreducible) cubic surface $S$ we give an explicit construction of a representative for each of the 72 equivalence classes of determinantal representations. Equivalence classes (under $\GL_3\times \GL_3$ action by left and right multiplication) ... More
On pairs of commuting nilpotent matricesDec 17 2007May 22 2008Let $B$ be a nilpotent matrix and suppose that its Jordan canonical form is determined by a partition $\lambda$. Then it is known that its nilpotent commutator $N_B$ is an irreducible variety and that there is a unique partition $\mu$ such that the intersection ... More
Burnett coefficients in quantum many-body systemsFeb 20 2013May 31 2013The Burnett coefficient B is investigated for transport in one-dimensional quantum many-body systems. Extensive numerical computations in spin-1/2 chains suggest a linear growth with time, B(t) \sim t, for non-integrable chains exhibiting diffusive transport. ... More
Reflected maxmin copulas and modelling quadrant subindependenceAug 23 2018Dec 11 2018Copula models have become popular in different applications, including modeling shocks, in view of their ability to describe better the dependence concepts in stochastic systems. The class of maxmin copulas was recently introduced by Omladi\v{c} and Ru\v{z}i\'{c}. ... More
Dynamical interstellar medium with Gaia and ground-based massive spectroscopic stellar surveysDec 21 2015The ongoing Gaia mission of ESA will provide accurate spatial and kinematical information for a large fraction of stars in the Galaxy. Interstellar extinction and line absorption studies toward a large number of stars at different distances and directions ... More
Exact asymptotics of the current in boundary dissipated quantum chains in large external fieldsJan 10 2015Boundary driven quantum master equation for a general inhomogeneous (non-integrable) anisotropic Heisenberg spin $1/2$ chain, or an equivalent nearest neighbor interacting spinless fermion chain, is considered in the presence of a strong external field ... More
Quantum metrology with non-equilibrium steady states of quantum spin chainsDec 05 2014We consider parameter estimations with probes being the boundary driven/dissipated non- equilibrium steady states of XXZ spin 1/2 chains. The parameters to be estimated are the dis- sipation coupling and the anisotropy of the spin-spin interaction. In ... More
Non-universal level statistics in a chaotic quantum spin chainFeb 15 2007We study the level statistics of an interacting multi-qubit system, namely the kicked Ising spin chain, in the regime of quantum chaos. Long range quasi-energy level statistics show effects analogous to the ones observed in semi-classical systems due ... More
Chaotic dephasing in a double-slit scattering experimentJun 02 2010Oct 06 2010We design a computational experiment in which a quantum particle tunnels into a billiard of variable shape and scatters out of it through a double-slit opening on the billiard's base. The interference patterns produced by the scattered probability currents ... More
Integrable quantum dynamics of open collective spin modelsJul 25 2018We consider a collective quantum spin-$s$ in contact with Markovian spin-polarized baths. Using a conserved super-operator charge, a differential representation of the Liouvillian is constructed to find its exact spectrum and eigen-modes. We study the ... More
On the computational complexity of degenerate unit distance representations of graphsJan 06 2010Some graphs admit drawings in the Euclidean k-space in such a (natu- ral) way, that edges are represented as line segments of unit length. Such drawings will be called k dimensional unit distance representations. When two non-adjacent vertices are drawn ... More
Overview of Annotation Creation: Processes & ToolsFeb 18 2016Creating linguistic annotations requires more than just a reliable annotation scheme. Annotation can be a complex endeavour potentially involving many people, stages, and tools. This chapter outlines the process of creating end-to-end linguistic annotations, ... More
A note on dilation coefficient, plane-width, and resolution coefficient of graphsJan 02 2010In this note we study and compare three graph invariants related to the 'compactness' of graph drawing in the plane: the dilation coefficient, defined as the smallest possible quotient between the longest and the shortest edge length; the plane-width, ... More
On the Size of Equifacetted Semi-Regular PolytopesSep 11 2011Unlike the situation in the classical theory of convex polytopes, there is a wealth of semi-regular abstract polytopes, including interesting examples exhibiting some unexpected phenomena. We prove that even an equifacetted semi-regular abstract polytope ... More
Ballistic spin transport in a periodically driven integrable quantum systemJan 16 2019Jan 25 2019We demonstrate ballistic spin transport of an integrable unitary quantum circuit, which can be understood either as a paradigm of an integrable periodically driven (Floquet) spin chain, or as a Trotterized anisotropic ($XXZ$) Heisenberg spin-1/2 model. ... More
Non-equilibrium quantum transport in presence of a defect: the non-interacting caseFeb 15 2018Dec 03 2018We study quantum transport after an inhomogeneous quantum quench in a free fermion lattice system in the presence of a localised defect. Using a new rigorous analytical approach for the calculation of large time and distance asymptotics of physical observables, ... More
Two dimensional kicked quantum Ising model: dynamical phase transitionsSep 09 2014Dec 31 2014Using an efficient one and two qubit gate simulator, operating on graphical processing units, we investigate ergodic properties of a quantum Ising spin 1/2 model on a two dimensional lattice, which is periodically driven by a $\delta$-pulsed transverse ... More
Spectral and Steady-State Properties of Random LiouvilliansMay 06 2019We study generic open quantum systems with Markovian dissipation, focusing on a class of stochastic Liouvillian operators of Lindblad form with independent random dissipation channels (jump operators) and a random Hamiltonian. We establish that the global ... More
NanocoolersJul 27 2011We present a simple kinematic model of a non-equilibrium steady state device, which can operate either as a heat engine or as a refrigerator. The model is composed of two or more scattering channels where the motion is fully described by deterministic ... More
Markovian kinetic equation approach to electron transport through quantum dot coupled to superconducting leadsJun 15 2012Oct 21 2012We present a derivation of Markovian master equation for the out of equilibrium quantum dot connected to two superconducting reservoirs, which are described by the Bogoliubov-de Gennes Hamiltonians and have the chemical potentials, the temperatures, and ... More
Counting One-Vertex MapsJan 03 2008The number of distinct maps (pre-maps) with a single vertex and valence $d$ is computed for any value of $d$. The types of maps (pre-maps) that we consider depend on whether the underlaying graph (pre-graph) is signed or unsigned and directed or undirected. ... More
Fictitious-time wave-packet dynamics in atomic systemsMay 27 2009Gaussian wave packets (GWPs) are well suited as basis functions to describe the time evolution of arbitrary wave functions in systems with nonsingular smooth potentials. They are less so in atomic systems on account of the singular behavior of the Coulomb ... More
Integrable Trotterization: Local Conservation Laws and Boundary DrivingDec 01 2017Dec 06 2017We discuss a general procedure to construct an integrable real-time trotterization of interacting lattice models. As an illustrative example we consider a spin-$1/2$ chain, with continuous time dynamics described by the isotropic ($XXX$) Heisenberg Hamiltonian. ... More
Semisymmetric Graphs from PolytopesJun 19 2006Every finite, self-dual, regular (or chiral) 4-polytope of type {3,q,3} has a trivalent 3-transitive (or 2-transitive) medial layer graph. Here, by dropping self-duality, we obtain a construction for semisymmetric trivalent graphs (which are edge- but ... More
Existence of Regular Nut Graphs and the Fowler ExtensionApr 03 2019In this paper the problem of the existence of regular nut graphs is addressed. A generalization of Fowler's extension which is a local enlargement applied to a vertex in a graph is introduced to generate nut graphs of higher order. Let $N(\rho)$ denote ... More
Upgrading EasyTime: from a textual to a visual languageAug 20 2012Measuring time in mass sports competitions is usually performed using expensive measuring devices. Unfortunately, these solutions are not acceptable by many organizers of sporting competitions. In order to make the measuring time as cheap as possible, ... More
Dimer Decimation and Intricately Nested Localized-Ballistic Phases of Kicked HarperFeb 09 2001Dimer decimation scheme is introduced in order to study the kicked quantum systems exhibiting localization transition. The tight-binding representation of the model is mapped to a vectorized dimer where an asymptotic dissociation of the dimer is shown ... More
Two-species hardcore reversible cellular automaton: matrix ansatz for dynamics and nonequilibrium stationary stateMar 25 2019May 20 2019In this paper we study the statistical properties of a reversible cellular automaton in two out-of-equilibrium settings. In the first part we consider two instances of the initial value problem, corresponding to the inhomogeneous quench and the local ... More
Dynamics and stability of Bose-Einstein condensates with attractive 1/r interactionMar 12 2008Apr 29 2008The time-dependent extended Gross-Pitaevskii equation for Bose-Einstein condensates with attractive 1/r interaction is investigated with both a variational approach and numerically exact calculations. We show that these condensates exhibit signatures ... More
Bifurcations, order, and chaos in the Bose-Einstein condensation of dipolar gasesFeb 27 2008Dec 09 2008We apply a variational technique to solve the time-dependent Gross-Pitaevskii equation for Bose-Einstein condensates in which an additional dipole-dipole interaction between the atoms is present with the goal of modelling the dynamics of such condensates. ... More
Non-exchangeability of copulas arising from shock modelsAug 29 2018Dec 11 2018When choosing the right copula for our data a key point is to distinguish the family that describes it at the best. In this respect, a better choice of the copulas could be obtained through the information about the (non)symmetry of the data. Exchangeability ... More
EasyTime++: A case study of incremental domain-specific language developmentMar 04 2013EasyTime is a domain-specific language (DSL) for measuring time during sports competitions. A distinguishing feature of DSLs is that they are much more amenable to change, and EasyTime is no exception in this regard. This paper introduces two new EasyTime ... More
Two-species hardcore reversible cellular automaton: matrix ansatz for dynamics and nonequilibrium stationary stateMar 25 2019In this paper we study the statistical properties of a reversible cellular automaton in two out-of-equilibrium settings. In the first part we consider two instances of the initial value problem, corresponding to the inhomogeneous quench and the local ... More
Accurate orbital solution for the new and metal poor eclipsing binary Tycho~5227-1023-1May 16 2017The orbit and physical parameters of the previously unsolved double-lined eclipsing binary Tyc 5227-1023-1, discovered during the search for RR Lyr variables candidate members of the Aquarius stream, are derived using high resolution \'echelle spectroscopy ... More
Interstellar medium, young stars, and astrometric binaries in Galactic archaeology spectroscopic surveysDec 21 2015Current ongoing stellar spectroscopic surveys (RAVE, GALAH, Gaia-ESO, LAMOST, APOGEE, Gaia) are mostly devoted to studying Galactic archaeology and structure of the Galaxy. But they allow for important auxiliary science: (i) Galactic interstellar medium ... More
Semitransitive subsemigroups of the singular part of the finite symmetric inverse semigroupFeb 09 2009We prove that the minimal cardinality of the semitransitive subsemigroup in the singular part $\IS_n\setminus \S_n$ of the symmetric inverse semigroup $\IS_n$ is $2n-p+1$, where $p$ is the greatest proper divisor of $n$, and classify all semitransitive ... More
Non-exchangeability of copulas arising from shock modelsAug 29 2018Feb 21 2019When choosing the right copula for our data a key point is to distinguish the family that describes it at the best. In this respect, a better choice of the copulas could be obtained through the information about the (non)symmetry of the data. Exchangeability ... More
Asymmetric linkages: maxmin vs. reflected maxmin copulasAug 23 2018Dec 12 2018In this paper we introduce some new copulas emerging from shock models, motivated by applications, i.e. the reflected maxmin copulas with dependent endogenous shocks and their extension to multivariate case. Our main goal is to show that reflected maxmin ... More
Slow quenches in two-dimensional time-reversal symmetric Z2 topological insulatorsFeb 15 2018Dec 28 2018We study the topological properties and transport in the Bernevig-Hughes-Zhang (BHZ) model undergoing a slow quench between different topological regimes. Due to the closing of the band gap during the quench, the system ends up in an excited state. For ... More
Super-diffusion in one-dimensional quantum lattice modelsJun 08 2018Dec 12 2018We identify a class of one-dimensional spin and fermionic lattice models which display diverging spin and charge diffusion constants, including several paradigmatic models of exactly solvable strongly correlated many-body dynamics such as the isotropic ... More
COINS: ContinuOus IntegratioN in wirelesS technology developmentApr 05 2018Jun 15 2018Network testing plays an important role in the iterative process of developing new communication protocols and algorithms. However, test environments have to keep up with the evolution of technology and require continuous update and redesign. In this ... More
Semitransitive and transitive subsemigroups of the inverse symmetric semigroupsSep 05 2007We classify minimal transitive subsemigroups of the finitary inverse symmetric semigroup modulo the classification of minimal transitive subgroups of finite symmetric groups; and semitransitive subsemigroups of the finite inverse symmetric semigroup of ... More
Slow Dynamics in Translation-Invariant Quantum Lattice ModelsJun 15 2017Mar 21 2018Many-body quantum systems typically display fast dynamics and ballistic spreading of information. Here we address the open problem of how slow the dynamics can be after a generic breaking of integrability by local interactions. We develop a method based ... More
On the resilience of magic number theory for conductance ratios of aromatic moleculesMar 08 2019If simple guidelines could be established for understanding how quantum interference (QI) can be exploited to control the flow of electricity through single molecules, then new functional molecules, which exploit room-temperature QI could be rapidly identified ... More
Convergence radius of perturbative Lindblad driven non-equilibrium steady statesFeb 09 2017Apr 04 2017We address the problem of analyzing the radius of convergence of perturbative expansion of non-equilibrium steady states of Lindblad driven spin chains. A simple formal approach is developed for systematically computing the perturbative expansion of small ... More
Discovery of a 21 Myr old stellar population in the Orion complexNov 28 2018Context: The Orion complex is arguably the most studied star-forming region in the Galaxy. While stars are still being born in the Orion nebula, the oldest part was believed to be no more than 13 Myr old. Aims: In order to study the full hierarchy of ... More
Exact large deviation statistics and trajectory phase transition of a deterministic boundary driven cellular automatonJan 03 2019We study the statistical properties of the long-time dynamics of the rule 54 reversible cellular automaton (CA), driven stochastically at its boundaries. This CA can be considered as a discrete-time and deterministic version of the Fredrickson-Andersen ... More
The GALAH survey: unresolved triple Sun-like stars discovered by the Gaia missionApr 09 2019The latest Gaia data release enables us to accurately identify stars that are more luminous than would be expected on the basis of their spectral type and distance. During an investigation of the 329 best Solar twin candidates uncovered among the spectra ... More
The Gaia-ESO Survey: Catalogue of H$α$ emission starsJul 14 2015We discuss the properties of H$\alpha$ emission stars across the sample of 22035 spectra from the Gaia-ESO Survey internal data release, observed with the GIRAFFE instrument and largely belonging to stars in young open clusters. Automated fits using two ... More
Pseudo Three-dimensional Maps of the Diffuse Interstellar Band at 862 nmAug 18 2014The diffuse interstellar bands (DIBs) are absorption lines observed in visual and near infrared spectra of stars. Understanding their origin in the interstellar medium (ISM) is one of the oldest problems in astronomical spectroscopy, as DIBs ahave been ... More
Chemical separation of disc components using RAVEMar 30 2016Jul 07 2016We present evidence from the RAdial Velocity Experiment (RAVE) survey of chemically separated, kinematically distinct disc components in the solar neighbourhood. We apply probabilistic chemical selection criteria to separate our sample into $\alpha$-low ... More
Improved distances and ages for stars common to TGAS and RAVEJul 14 2017Apr 18 2018We combine parallaxes from the first Gaia data release with the spectrophotometric distance estimation framework for stars in the fifth RAVE survey data release. The combined distance estimates are more accurate than either determination in isolation ... More
The RAVE-on catalog of stellar atmospheric parameters and chemical abundances for chemo-dynamic studies in the Gaia eraSep 09 2016The orbits, atmospheric parameters, chemical abundances, and ages of individual stars in the Milky Way provide the most comprehensive illustration of galaxy formation available. The Tycho-Gaia Astrometric Solution (TGAS) will deliver astrometric parameters ... More
The GALAH survey: unresolved triple Sun-like stars discovered by the Gaia missionApr 09 2019May 16 2019The latest Gaia data release enables us to accurately identify stars that are more luminous than would be expected on the basis of their spectral type and distance. During an investigation of the 329 best Solar twin candidates uncovered among the spectra ... More
Holistic spectroscopy: Complete reconstruction of a wide-field, multi-object spectroscopic image using a photonic combApr 16 2018The primary goal of Galactic archaeology is to learn about the origin of the Milky Way from the detailed chemistry and kinematics of millions of stars. Wide-field multi-fibre spectrographs are increasingly used to obtain spectral information for huge ... More
The selection function of the RAVE surveyNov 02 2016The selection function of a sample of observed objects quantifies the probability that a given target would have been observed and included in the final catalogue. Knowledge of this function is indispensable for any statistical analysis of such a sample. ... More
The selection function of the RAVE surveyNov 02 2016Mar 09 2017We characterize the selection function of RAVE using 2MASS as our underlying population, which we assume represents all stars which could have potentially been observed. We evaluate the completeness fraction as a function of position, magnitude, and color ... More
The GALAH survey: a catalogue of carbon-enhanced stars and CEMP candidatesJul 20 2018Nov 20 2018Swan bands - characteristic molecular absorption features of the C$_2$ molecule - are a spectroscopic signature of carbon-enhanced stars. They can also be used to identify carbon-enhanced metal-poor (CEMP) stars. The GALAH (GALactic Archaeology with Hermes) ... More
The GALAH Survey and Gaia DR2: (Non)existence of five sparse high-latitude open clustersJul 02 2018Sparse open clusters can be found at high galactic latitudes where loosely populated clusters are more easily detected against the lower stellar background. Because most star formation takes place in the thin disk, the observed population of clusters ... More
The GALAH survey: The data reduction pipelineAug 15 2016We present the data reduction procedures being used by the GALAH survey, carried out with the HERMES fibre-fed, multi-object spectrograph on the 3.9~m Anglo-Australian Telescope. GALAH is a unique survey, targeting 1 million stars brighter than magnitude ... More
The GALAH survey: Co-orbiting stars and chemical taggingApr 16 2018Jun 19 2018We present a study using the second data release of the GALAH survey of stellar parameters and elemental abundances of 15 pairs of stars identified by Oh et al 2017. They identified these pairs as potentially co-moving pairs using proper motions and parallaxes ... More
The GALAH survey: Chemical Tagging of Star Clusters and New Members in the PleiadesSep 04 2017The technique of chemical tagging uses the elemental abundances of stellar atmospheres to `reconstruct' chemically homogeneous star clusters that have long since dispersed. The GALAH spectroscopic survey --which aims to observe one million stars using ... More
The GALAH and TESS-HERMES surveys: high-resolution spectroscopy of luminous supergiants in the Magellanic Clouds and BridgeApr 16 2018Apr 19 2018We report the serendipitous observations of 571 luminous supergiants in the Magellanic Clouds by the spectroscopic GALAH and TESS-HERMES surveys: 434 stars in the Large Magellanic Cloud and 137 in the Small Magellanic Cloud. We also find one star that ... More
The GALAH Survey: Accurate Radial Velocities and Library of Observed Stellar Template SpectraApr 17 2018Sep 06 2018GALAH is a large-scale magnitude-limited southern stellar spectroscopic survey. Its second data release (GALAH DR2) provides values of stellar parameters and abundances of 23 elements for 342,682 stars (Buder et al.). Here we add a description of the ... More