Publications (51)
Dualism of the 4f electrons and high-temperature antiferromagnetism of the heavy-fermion compound YbCoC
D. A. Salamatin, N. Martin, V. A. Sidorov +9
We report on the first study of the noncentrosymmetric ternary carbide YbCoC. Our magnetization, specific heat, resistivity and neutron diffraction measurements consistently…
The StEllar Counterparts of COmpact high velocity clouds (SECCO) survey. II. Sensitivity of the survey and an Atlas of Synthetic Dwarf Galaxies
G. Beccari, M. Bellazzini, G. Battaglia +5
SECCO is a survey devoted to the search for stellar counterparts within Ultra Compact High Velocity Clouds. In this contribution we present the results of a set of simulations aime…
Nonlocal corrections to dynamical mean-field theory from the two-particle self-consistent method
N. Martin, C. Gauvin-Ndiaye, A. -M. S. Tremblay
Theoretical methods that are accurate for both short-distance observables and long-wavelength collective modes are still being developed for the Hubbard model. Here, we benchmark a…
Field-induced vortex-like textures as a probe of the critical line in reentrant spin glasses
N. Martin, L. J. Bannenberg, M. Deutsch +4
We study the evolution of the low-temperature field-induced magnetic defects observed under an applied magnetic field in a series of frustrated amorphous ferromagnets (FeMn…
Magnetic ground state and spin fluctuations in MnGe chiral magnet as studied by Muon Spin Rotation
N. Martin, M. Deutsch, F. Bert +9
We have studied by muon spin resonance (μSR) the helical ground state and fluctuating chiral phase recently observed in the MnGe chiral magnet. At low temperature, the muon polari…
The metal-poor tail of the APOGEE survey II. Spectral analysis of Mg and Si in very metal-poor APOGEE spectra
M. Montelius, A. Angrilli Muglia, E. Starkenburg +9
H-band spectra contain very limited spectral information for stars at the most metal-poor tail ( Fe/H < -2.5) because the available Fe lines in FGK stars in this wavelength range a…
Empirical phi-divergence test statistics in the logistic regression model
A. Felipe, P. Garcia-Segador, N. Martin +2
In this paper we apply divergence measures to empirical likelihood applied to logistic regression models. We define a family of empirical test statistics based on divergence measur…
The kinematic footprints of five stellar streams in Andromeda's halo
S. C. Chapman, R. Ibata, M. Irwin +12
(abridged) We present a spectroscopic analysis of five stellar streams (`A', `B', `Cr', `Cp' and `D') as well as the extended star cluster, EC4, which lies within streamC, all disc…
Globular Clusters in the Sagittarius stream. Revising members and candidates with Gaia DR2
M. Bellazzini, R. Ibata, K. Malhan +3
We reconsider the case for the association of Galactic globular clusters (GCs) to the tidal stream of the Sagittarius dwarf spheroidal galaxy (Sgr dSph), using Gaia DR2 data. We us…
Robust Estimators and Test-Statistics for One-Shot Device Testing Under the Exponential Distribution
N. Balakrishnan, E. Castilla, N. Martin +1
This paper develops a new family of estimators, the minimum density power divergence estimators (MDPDEs), for the parameters of the one-shot device model as well as a new family of…
Power divergence approach for one-shot device testing under competing risks
N. Balakrishnan, E. Castilla, N. Martin +1
Most work on one-shot devices assume that there is only one possible cause of device failure. However, in practice, it is often the case that the products under study can experienc…
MOONS Surveys of the Milky Way and its Satellites
O. A. Gonzalez, A. Mucciarelli, L. Origlia +37
The study of resolved stellar populations in the Milky Way and other Local Group galaxies can provide us with a fossil record of their chemo-dynamical and star-formation histories…
Divergence-based robust inference under proportional hazards model for one-shot device life-test
N. Balakrishnan, E. Castilla, N. Martin +1
In this paper, we develop robust estimators and tests for one-shot device testing under proportional hazards assumption based on divergence measures. Through a detailed Monte Carlo…
Detection of the Canis Major galaxy at (l;b)=(244;-8) and in the background of Galactic open clusters
M. Bellazzini, R. Ibata, L. Monaco +3
We report on the detection of Main Sequence stars belonging to the recently identified Canis Major galaxy in a field located at ~ 4.2 deg from the center of the stellar system. Wit…
Disorder and Quantum spin ice
N. Martin, P. Bonville, E. Lhotel +7
We report on diffuse neutron scattering experiments providing evidence for the presence of random strains in the quantum spin ice candidate Pr2Zr2O7. Since Pr is a non-Kramers ion,…
The Two-Particle Self-Consistent Approach for Multiorbital models: application to the Emery model
C. Gauvin-Ndiaye, J. Leblanc, S. Marin +3
The Emery model, or three-band Hubbard model, is a Hamiltonian that is thought to contain much of the physics of cuprate superconductors. This model includes two noninteracting …
Gemini/GRACES Spectroscopy of Stars in Triangulum II
K. A. Venn, E. Starkenburg, L. Malo +2
The chemical abundance ratios and radial velocities for two stars in the recently discovered Triangulum II faint dwarf galaxy have been determined from high resolution, medium sign…
The core of the Canis Major galaxy as traced by Red Clump stars
M. Bellazzini, R. Ibata, N. Martin +3
The recently-discovered stellar system in Canis Major is analysed using He-burning Red Clump stars as tracers. Canis Major turns out to be the strongest and most spatially confined…
Controlling coherence between waveguide-coupled quantum dots
D. Hallett, J. Wiercinski, L. Hallacy +10
We present a novel waveguide design that incorporates a split-diode structure, allowing independent electrical control of transition energies of multiple emitters over a wide range…
Low Temperature Formation of Crystalline VO2 Domains in Porous 1 Nanocolumnar Thin Films for Thermochromic Applications
H. Acosta-Rivera, V. Rico, F. J. Ferrer +5
The formation of VO2 crystalline domains in amorphous substoichiometric nanocolumnar VOx thin films subjected to an oxidation process at temperatures below 300°C has been studied.…
Evolution of magneto-crystalline anisotropies in MnFeSi and MnCoSi as inferred from small-angle neutron scattering and bulk properties
J. Kindervater, T. Adams, A. Bauer +12
We report a comprehensive small-angle neutron scattering~(SANS) study of MnFeSi at zero magnetic field. To delineate changes of magneto-crystalline anisotropies (MCAs…
CASCADE - a multi-layer Boron-10 neutron detection system
M. Köhli, M. Klein, F. Allmendinger +5
The globally increased demand for helium-3 along with the limited availability of this gas calls for the development of alternative technologies for the large ESS instrumentation p…
Spin Textures induced by Quenched Disorder in a Reentrant Spin Glass: Vortices versus "Frustrated" Skyrmions
I. Mirebeau, N. Martin, M. Deutsch +6
Reentrant spin glasses are frustrated disordered ferromagnets developing vortex-like textures under an applied magnetic field. Our study of a NiMn single crystal…
The Pristine survey II: a sample of bright stars observed with FEROS
E. Caffau, P. Bonifacio, E. Starkenburg +8
Extremely metal-poor (EMP) stars are old objects formed in the first Gyr of the Universe. They are rare and, to select them, the most successful strategy has been to build on large…
A very dark stellar system lost in Virgo: kinematics and metallicity of SECCO1 with MUSE
G. Beccari, M. Bellazzini, L. Magrini +11
We present the results of VLT-MUSE integral field spectroscopy of SECCO1, a faint, star-forming stellar system recently discovered as the stellar counterpart of an Ultra Compact Hi…
The StEllar Counterparts of COmpact high velocity clouds (SECCO) survey. I. Photos of ghosts
M. Bellazzini, G. Beccari, G. Battaglia +6
We present an imaging survey aimed at searching for the stellar counterparts of recently discovered ultra-compact high-velocity HI clouds (UCHVC). Adams et al. (2013) proposed thes…
Long period helical structures and twist-grain boundary phases induced by non magnetic ion doping in Mn(Co,Rh)Ge chiral magnet
N. Martin, M. Deutsch, G. Chaboussant +6
We study the evolution of helical magnetism in MnGe chiral magnet upon partial substitution of Mn for non magnetic 3d-Co and 4d-Rh ions. At high doping levels, we observe spin heli…
Dynamics in the satellite system of Triangulum: Is AndXXII a dwarf satellite of M33?
S. C. Chapman, L. Widrow, M. L. M. Collins +10
We present results from a spectroscopic survey of the dwarf spheroidal And XXII and the two extended clusters EC1 and EC2. These three objects are candidate satellites of the Trian…
The Pluto system: Initial results from its exploration by New Horizons
S. A. Stern, F. Bagenal, K. Ennico +148
The Pluto system was recently explored by NASA's New Horizons spacecraft, making closest approach on 14 July 2015. Pluto's surface displays diverse landforms, terrain ages, albedos…
On the resolution of a MIEZE spectrometer
N. Martin
We study the effect of a finite sample size, beam divergence and detector thickness on the resolution function of a MIEZE spectrometer. We provide a transparent analytical framewor…
Spectroscopic Signatures of Photogenerated Radical Anions in Polymer-[C70]Fullerene Bulk Heterojunctions
M. Liedtke, A. Sperlich, H. Kraus +6
Light induced polarons in solid films of polymer-fullerene blends were studied by applying photoluminescence (PL), photo induced absorption (PIA) techniques as well as electron spi…
The metal-poor tail of the APOGEE survey I. Uncovering [Fe/H] < -2.5 stars from the inner Galaxy to the Magellanic Clouds
M. Montelius, E. Starkenburg, H. Woudenberg +9
In the search for metal-poor stars, large spectroscopic surveys are an invaluable tool. However, the spectra of metal-poor stars can be difficult to analyse because of the relative…
Onset of a skyrmion phase by chemical substitution in MnGe chiral magnet
E. Altynbaev, N. Martin, A. Heinemann +4
We study the evolution of the magnetic phase diagram of MnFeGe alloys with concentration () by small-angle neutron scattering. We unambiguously…
Lifetime of Gapped Excitations in a Collinear Quantum Antiferromagnet
A. L. Chernyshev, M. E. Zhitomirsky, N. Martin +1
We demonstrate that local modulations of magnetic couplings have a profound effect on the temperature dependence of the relaxation rate of optical magnons in a wide class of antife…
The Hubble Space Telescope Survey of M31 Satellite Galaxies II. The Star Formation Histories of Ultra-Faint Dwarf Galaxies
A. Savino, D. R. Weisz, E. D. Skillman +34
We present the lifetime star formation histories (SFHs) for six ultra-faint dwarf (UFD; , ) satellite galaxies of M31 based on…
The Pristine survey -- XV. A CFHT ESPaDOnS view on the Milky Way halo and disc populations
R. Lucchesi, C. Lardo, P. Jablonka +14
We present a one-dimensional, local thermodynamic equilibrium (1D-LTE) homogeneous analysis of 132 stars observed at high-resolution with ESPaDOnS. This represents the largest samp…
Young stars raining through the Galactic Halo: the nature and orbit of Price-Whelan 1
M. Bellazzini, R. A. Ibata, N. Martin +3
We present radial velocities for five member stars of the recently discovered young (age= 100-150 Myr) stellar system Price-Whelan 1 (PW 1), that is located far away in the Galacti…
Neutron spin echo spectroscopy under 17T magnetic field at RESEDA
J. Kindervater, N. Martin, W. HäuÃler +7
We report proof-of-principle measurements at the neutron resonance spin echo spectrometer RESEDA (MLZ) under large magnetic fields by means of Modulation of IntEnsity with Zero Eff…
The Hubble Space Telescope Survey of M31 Satellite Galaxies IV. Survey Overview and Lifetime Star Formation Histories
A. Savino, D. R. Weisz, A. E. Dolphin +35
From orbits of HST imaging, we present deep homogeneous resolved star color-magnitude diagrams that reach the oldest main sequence turnoff and uniformly measured star forma…
Strangers in the night: Discovery of a dwarf spheroidal galaxy on its first Local Group infall
S. C. Chapman, J. Penarrubia, R. Ibata +9
We present spectroscopic observations of the AndXII dwarf spheroidal galaxy using DEIMOS/Keck-II, showing it to be moving rapidly through the Local Group (-556 km/s heliocentric ve…
Split of the magnetic and crystallographic states in FeRhGe
D. O. Skanchenko, E. V. Altynbaev, V. A. Sidorov +8
We report on a comprehensive experimental and theoretical study of FeRhGe compounds, within the entire concentration range , using X-Ray…
Reorientations, relaxations, metastabilities and multidomains of skyrmion lattices
L. J. Bannenberg, F. Qian, R. M. Dalgliesh +7
Magnetic skyrmions are nano-sized topologically protected spin textures with particle-like properties. They can form lattices perpendicular to the magnetic field and the orientatio…
A Keck/DEIMOS spectroscopic survey of the faint M31 satellites And XV and And XVI
B. Letarte, S. C. Chapman, M. Collins +7
We present the results of a spectroscopic survey of the recently discovered M31 satellites And XV and And XVI, lying at projected distances from the centre of M31 of 93 and 130 kpc…
A Pristine-UNIONS view on the Galaxy: Kinematics of the distant spur feature of the Sagittarius stream traced by Blue Horizontal Branch stars
M. Bayer, E. Starkenburg, G. F. Thomas +14
Providing a detailed picture of the Sagittarius (Sgr) stream offers important constraints on the build-up of the Galactic halo as well as its gravitational potential at large radii…
HII regions within a compact high velocity cloud. A nearly star-less dwarf galaxy?
M. Bellazzini, L. Magrini, A. Mucciarelli +9
Within the SECCO survey we identified a candidate stellar counterpart to the Ultra Compact High Velocity Cloud (UCHVC) HVC274.68+74.70-123, that was suggested by Adams et al. (2013…
Interaction and temperature effects on the magneto-optical conductivity of Weyl liquids
S. Acheche, R. Nourafkan, J. Padayasi +2
Negative magnetoresistance is one of the manifestations of the chiral anomaly in Weyl semimetals. The magneto-optical conductivity also shows transitions between Landau levels that…
The Pristine survey. XXVI. Chemical abundances of subgiant stars of the extremelymetal-poor stream C-19
P. Bonifacio, E. Caffau, P. François +17
Context: The C-19 stellar stream is the most metal-poor stream known to date. While its width and velocity dispersion indicate a dwarf galaxy origin, its metallicity spread and abu…
Neutron Resonance Spin Flippers: Static Coils Manufactured by Electrical Discharge Machining
N. Martin, J. N. Wagner, M. Dogú +4
Radiofrequency spin flippers (RFSF) are key elements of Neutron Resonance Spin Echo (NRSE) spectrometers, which allow performing controlled manipulations of the beam polarization.…
Anisotropic fractal magnetic domain pattern in bulk MnPtSn
A. S. Sukhanov, B. E. Zuniga Cespedes, P. Vir +9
The tetragonal compound MnPtSn with the symmetry recently attracted attention as the first known material that hosts magnetic antiskyrmions, which differ from the…
Increasing the skyrmion stability in CuOSeO by chemical substitution
A. S. Sukhanov, Praveen Vir, A. S. Cameron +7
The cubic chiral helimagnets with the space group represent a group of compounds in which the stable skyrmion-lattice state is experimentally observed. The key parameter th…
Magnetovolume effect, macroscopic hysteresis and moment collapse in the paramagnetic state of cubic MnGe under pressure
N. Martin, I. Mirebeau, M. Deutsch +6
Itinerant magnets generally exhibit pressure induced transitions towards non magnetic states. Using synchrotron based X-ray diffraction and emission spectroscopy, the evolution of…