Publications associées à Pulsar

Stellar Metallicities and Gradients in the Isolated, Quenched Low-mass Galaxy Tucana

We measure the metallicities of 374 red giant branch (RGB) stars in the isolated, quenched dwarf galaxy Tucana using Hubble Space Telescope (HST) narrow-band (F395N) Calcium H & K (CaHK) imaging. Our sample is a factor of similar to 7 similar to 7 larger t ...

Iop Publishing Ltd2024

Characterization of High Harmonic Frequencies in Reactor Noise Experiments Within the CORTEX Project

Andreas Pautz, Vincent Pierre Lamirand

We present a novel technique of neutron noise detection and experimental data interpretation developed during the EU H2020 project CORTEX aiming to improve the capabilities for identification and localization of neutron noise sources. The experimental data ...

2022

Rotation measure and synchrotron emission signatures in simulations of magnetized galactic discs

Jennifer Waltraud Schober, Yoan Rappaz

We analyse observational signatures of magnetic fields for simulations of a Milky Way-like disc with supernova-driven interstellar turbulence and self-consistent chemical processes. In particular, we post-process two simulations data sets of the SILCC Proj ...

OXFORD UNIV PRESS2022

HD 60431, the CP2 star with the shortest rotational period Physical parameters and period analysis

Pierre North

Context. CP2 stars show periodic photometric, spectroscopic, and magnetic variations with the rotational period. They are generally slow rotators, with rotational periods exceeding half a day, except for the late B-type star HD 60431, which has an unusuall ...

EDP SCIENCES S A2022

A novel measurement of marginal Alfven eigenmode stability during high power auxiliary heating in JET

Ambrogio Fasoli, Mario Ludovico Podesta, Paulo Giovane Paschoali Pereira Puglia

The interaction of Alfven eigenmodes (AEs) and energetic particles is one of many important factors determining the success of future tokamaks. In JET, eight in-vessel antennas were installed to actively probe stable AEs with frequencies ranging 25-250 kHz ...

IOP Publishing Ltd2022

Gravitational wave signal from primordial magnetic fields in the Pulsar Timing Array frequency band

Andrii Neronov

The NANOGrav, Parkes, European, and International Pulsar Timing Array (PTA) Collaborations have reported evidence for a common-spectrum process that can potentially correspond to a stochastic gravitational wave background (SGWB) in the 1-100 nHz frequency ...

American Physical Society2022

Development of a new method to determine the axial void velocity profile in BWRs from measurements of the in-core neutron noise

Mathieu Hursin

Determination of the local void fraction in BWRs from in-core neutron noise measurements requires the knowledge of the axial velocity of the void. The purpose of this paper is to revisit the problem of determining the axial void velocity profile from the t ...

PERGAMON-ELSEVIER SCIENCE LTD2021

Secular effects of ultralight dark matter on binary pulsars

Sergey Sibiryakov, Diego Blas Temino

Dark matter (DM) can consist of very light bosons behaving as a classical scalar field that experiences coherent oscillations. The presence of this DM field would perturb the dynamics of celestial bodies, either because the (oscillating) DM stress tensor m ...

American Physical Society2020

How stellar rotation shapes the colour-magnitude diagram of the massive intermediate-age star cluster NGC 1846

Carmela Lardo

We present a detailed study of stellar rotation in the massive 1.5 Gyr old cluster NGC 1846 in the Large Magellanic Cloud. Similar to other clusters at this age, NGC 1846 shows an extended main-sequence turn-off (eMSTO), and previous photometric studies ha ...

OXFORD UNIV PRESS2020

Experimental and numerical study of stochastic branching noise in nuclear reactors

Oskari Ville Pakari

Noise analysis applied to nuclear reactor physics is a powerful tool to investigate a reactor's kinetic parameters, and more generally underlying physical processes determining core behavior. The kinetic parameters are the coefficients of simplified time-d ...

EPFL2020

Development of Advanced Methodologies for Monitoring and Modelling of Neutron Noise in Modern LWR Cores

Dionysios Chionis

Nuclear reactors are inherently stochastic systems, in which neutronic and thermal-hydraulic parameters fluctuate continuously even during steady-state conditions. In addition, structural components vibrate due to the coolant hydraulic forces. This stochas ...

EPFL2020

Propagating transport-code input parameter uncertainties with deterministic sampling

Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Martinus Gijs, Jonathan Graves, Yves Martin, Duccio Testa, Patrick Blanchard, Bruno Emanuel Ferreira De Sousa Correia, Alessandro Pau, Pierre-Thomas Paul Brun, Cristian Sommariva, Henri Weisen, Richard Pitts, Sun Hee Kim, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Mikhail Maslov, Nicola Vianello, Miguel Fernández Ruiz, Federico Nespoli, Antonio José Pereira de Figueiredo, Liang Yao, Yao Zhou, David Pfefferlé, Dalziel Joseph Wilson, Robin Humphry-Baker, Davide Galassi, José Pedro Rebelo Ferreira Marques, Ana Francisca Leal Silva Soares, Jonathan Marc Philippe Faustin, Daniel Scott Alessi, Arnout Lodewijk M Beckers, Julio Rodriguez, Hamish William Patten, Jonnathan Cesar Hidalgo Acosta, , , , , , , , ,

Ultralight Dark Matter Resonates with Binary Pulsars

Sergey Sibiryakov, Diego Blas Temino

We consider the scenario where dark matter (DM) is represented by an ultralight classical scalar field performing coherent periodic oscillations. We point out that such DM perturbs the dynamics of binary systems either through its gravitational field or vi ...

American Physical Society2017

Constraints on violation of Lorentz invariance from atmospheric showers initiated by multi-TeV photons

Sergey Sibiryakov

Parameterizing hypothetical violation of Lorentz invariance at high energies using the framework of effective quantum field theory, we discuss its effect on the formation of atmospheric showers by very-high-energy gamma rays. In the scenario where Lorentz ...

Iop Publishing Ltd2017

Teraelectronvolt pulsed emission from the Crab Pulsar detected by MAGIC

Thomas Günther Bretz

Aims. We investigate the extension of the very high-energy spectral tail of the Crab Pulsar at energies above 400 GeV. Methods. We analyzed similar to 320 h of good-quality Crab data obtained with the MAGIC telescope from February 2007 to April 2014. Resul ...

Edp Sciences S A2016

On constraining the speed of gravitational waves following GW150914

Sergey Sibiryakov, Diego Blas Temino, Mikhail Ivanov

We point out that the observed time delay between the detection of the signal at the Hanford and Livingston LIGO sites from the gravitational wave event GW150914 places an upper bound on the speed of propagation of gravitational waves, c (gw) ae(2) 1.7 in ...

Springer Verlag2016

Femtosecond pulse length and arrival time measurement of hard X-Ray FELs

Ishkhan Gorgisyan

The ultra-bright short-pulsed radiation provided by the free electron lasers (FEL) is used for many new discoveries in different fields of science and industry. The advancement of the FEL technologies allows the generation of shorter photon pulses with hig ...

EPFL2016

Laser arrival measurement tools for SwissFEL

Christoph Peter Hauri

SwissFEL is aiming to produce X-ray pulses from 30 fs down to the attosecond time scale. This requires the compression of the several picosecond long electron bunches produced by a photo-injector to sub-fs level. To achieve this, 40fs accurate injection of ...

Spie-Int Soc Optical Engineering2015

MAGIC reveals a complex morphology within the unidentified gamma-ray source HESS J1857+026

Thomas Günther Bretz

Aims. HESS J1857+026 is an extended TeV gamma-ray source that was discovered by H. E. S. S. as part of its Galactic plane survey. Given its broadband spectral energy distribution and its spatial coincidence with the young energetic pulsar PSR J1856+0245, t ...

Edp Sciences S A2014

Weak lensing galaxy cluster field reconstruction

Jean-Paul Richard Kneib, Mathilde Jauzac

In this paper, we compare three methods to reconstruct galaxy cluster density fields with weak lensing data. The first method called FLens integrates an inpainting concept to invert the shear field with possible gaps, and a multi-scale entropy denoising pr ...

Wiley-Blackwell2014