Publications associées à Raies de Fraunhofer

CEERS Key Paper. VIII. Emission-line Ratios from NIRSpec and NIRCam Wide-Field Slitless Spectroscopy at z > 2

We use James Webb Space Telescope Near-Infrared Camera Wide Field Slitless Spectroscopy (NIRCam WFSS) and the Near-Infrared spectrograph (NIRSpec) in the Cosmic Evolution Early Release survey to measure rest-frame optical emission-line ratios of 155 galaxi ...

Iop Publishing Ltd2024

Spectroscopic characterisation of TCV divertor towards a detached regime

Lorenzo Martinelli

The challenge of power exhaust of the high heat and particle fluxes foreseen for ITER and the forthcoming nuclear fusion reactors can be mitigated by operating in a detached divertor regime. This regime has been the object of three decades of studies, as i ...

EPFL2023

Optical and mid-infrared line emission in nearby Seyfert galaxies

Michaela Hirschmann

Line ratio diagnostics provide valuable clues as to the source of ionizing radiation in galaxies with intense black hole accretion and starbursting events, such as local Seyfert galaxies or galaxies at the peak of their star formation history. We aim to pr ...

2023

Numerical simulations of gas puff imaging using a multi-component model of the neutral-plasma interaction in the tokamak boundary

Paolo Ricci

A three-dimensional simulation of gas puff imaging (GPI) diagnostics is carried out by using a self-consistent multi-component model of the neutral-plasma interaction. The simulation, based on the drift-reduced Braginskii model for the plasma and a kinetic ...

AIP Publishing2022

A novel hydrogenic spectroscopic technique for inferring the role of plasma-molecule interaction on power and particle balance during detached conditions

Basil Duval, Artur Perek, Kevin Henricus Annemarie Verhaegh, Mirko Wensing

Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced through plasma-atom and plasma-molecule interactions. Experimental research in how those reactions pre ...

IOP PUBLISHING LTD2021

Photonic chip-based resonant supercontinuum via pulse-driven Kerr microresonator solitons

Tobias Kippenberg, Junqiu Liu, Wenle Weng, Tobias Herr, Miles Henry Anderson

Supercontinuum generation and soliton microcomb formation both represent key techniques for the formation of coherent, ultrabroad optical frequency combs, enabling the RF-to-optical link. Coherent supercontinuum generation typically relies on ultrashort pu ...

2021

A study of the influence of plasma-molecule interactions on particle balance during detachment

Basil Duval, Christian Gabriel Theiler, Kevin Henricus Annemarie Verhaegh, Artur Perek, Mirko Wensing

In this work we provide experimental insights into the impact of plasma-molecule interactions on the target ion flux decrease during divertor detachment achieved through a core density ramp in the TCV tokamak. Our improved analysis of the hydrogen Balmer s ...

Elsevier2021

Cepheids with Giant Companions. I. Revealing a Numerous Population of Double-lined Binary Cepheids* (dagger)

Richard Irving Anderson

Masses of classical Cepheids of 3-11 M are predicted by theory but those measured clump between 3.6-5 M. As a result, their mass-luminosity relation is poorly constrained, impeding our understanding of basic stellar physics and the Leavitt Law. All Cepheid ...

2021

Low-dimensional perovskite nanoplatelet synthesis using in situ photophysical monitoring to establish controlled growth

Perovskite nanoparticles have attracted the attention of research groups around the world for their impressive photophysical properties, facile synthesis and versatile surface chemistry. Here, we report a synthetic route that takes advantage of a suite of ...

2019

MANTIS: A real-time quantitative multispectral imaging system for fusion plasmas

Basil Duval, Cristian Galperti, Yanis Andrebe, Artur Perek, Kevin Henricus Annemarie Verhaegh, Wouter Vijvers

This work presents a novel, real-time capable, 10-channel Multispectral Advanced Narrowband Tokamak Imaging System installed on the TCV tokamak, MANTIS. Software and hardware requirements are presented together with the complete system architecture. The im ...

AMER INST PHYSICS2019

Determination of isotope ratio in the divertor of JET-ILW by high-resolution H alpha spectroscopy: H-D experiment and implications for D-T experiment

Olivier Sauter, Ambrogio Fasoli, Stefano Coda, Basil Duval, Jonathan Graves, Duccio Testa, Henri Weisen, Yves Martin, Federico Nespoli, David Pfefferlé, Patrick Blanchard, Jonathan Marc Philippe Faustin, Hamish William Patten, Alessandro Pau, Samuel Lanthaler, Cristian Sommariva, Stéphanie Prior, Richard Pitts, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Yao Zhou, Davide Galassi, Antonio José Pereira de Figueiredo, Liang Yao, Dalziel Joseph Wilson, Bernhard Sieglin, Otto Asunta

The data of the H alpha high-resolution spectroscopy, collected on the multiple lines of sight, which cover the entire divertor space in poloidal cross-section, during the recent hydrogen-deuterium experiments in JET-ILW (ITER-like wall), are processed. A ...

IOP Publishing Ltd2019

Quasi-stellar objects acting as potential strong gravitational lenses in the SDSS-III BOSS survey

Jean-Paul Richard Kneib, Frédéric Courbin, Timothée Guy Olivier Delubac

We present a sample of 12 quasi-stellar objects (QSOs) that potentially act as strong gravitational lenses on background emission line galaxies (ELG) or Lyman-alpha emitters (LAEs) selected through a systematic search of the 297 301 QSOs in the Sloan Digit ...

EDP SCIENCES S A2019

Reconfigurable optical generation of nine Nyquist WDM channels with sinc-shaped temporal pulse trains using a single microresonator-based Kerr frequency comb

Tobias Kippenberg, Maxim Karpov, Martin Hubert Peter Pfeiffer, Arne Kordts, Fatemeh Alishahi, Ahmad Fallahpour, Amirhossein Mohajerin Ariaei, Cong Liu

Sinc-shaped temporal pulse trains have a spectrally efficient, rectangular Nyquist spectrum. We demonstrate the simultaneous and reconfigurable optical generation of multiple Nyquist-shaped wavelength-division-multiplexed (WDM) channels having temporal sin ...

OPTICAL SOC AMER2019

Observation of the 1S-2P Lyman-alpha transition in antihydrogen

Shirit Cohen

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum(1,2). The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now ...

Nature Publishing Group2018

Stark broadening of Balmer lines with low and moderate quantum number in dense divertor plasmas

Basil Duval, Kevin Henricus Annemarie Verhaegh

A computer simulation technique is applied to the modelling of Balmer line shapes in dense divertor conditions. The spectral profile of lines with a high principal quantum number n is sensitive to Stark broadening and can be used as a density diagnostic. I ...

2018

Dissecting cold gas in a high-redshift galaxy using a lensed background quasar

Frédéric Courbin

We present a study of cold gas absorption from a damped Lyman-alpha absorber (DLA) at redshift z(abs) = 1.946 toward two lensed images of the quasar J144254.78+405535.5 at redshift z(QSO) = 2.590. The physical separation of the two lines of sight at the ab ...

EDP SCIENCES S A2018

The Gaia-ESO Survey: dynamics of ionized and neutral gas in the Lagoon nebula (M 8)

Carmela Lardo

Aims. We present a spectroscopic study of the dynamics of the ionized and neutral gas throughout the Lagoon nebula (M 8), using VLT-FLAMES data from the Gaia-ESO Survey. The new data permit exploration of the physical connections between the nebular gas an ...

Edp Sciences S A2017

The Pristine survey - III. Spectroscopic confirmation of an efficient search for extremely metal-poor stars

Pascale Jablonka, Marc Gentile

The Pristine survey is a narrow-band, photometric survey focused around the wavelength region of the Ca II H&K absorption lines, designed to efficiently search for extremely metal-poor stars. In this work, we use the first results of amedium-resolution spe ...

Oxford Univ Press2017

Spectroscopic investigations of divertor detachment in TCV

Basil Duval, Christian Gabriel Theiler, Holger Reimerdes, Benoît Labit, Umar Sheikh, Nicola Vianello, Federico Nespoli, Cedric Kar-Wai Tsui, Kevin Henricus Annemarie Verhaegh, Wouter Vijvers, Roberto Maurizio, Claudio Marini

The aim of this work is to provide an understanding of detachment at TCV with emphasis on analysis of the Balmer line emission. A new Divertor Spectroscopy System has been developed for this purpose. Further development of Balmer line analysis techniques h ...

Elsevier2017

NEAR-ULTRAVIOLET SPECTROSCOPY OF STAR-FORMING GALAXIES FROM eBOSS: SIGNATURES OF UBIQUITOUS GALACTIC-SCALE OUTFLOWS

Jean-Paul Richard Kneib, Johan Comparat, Anand Stéphane Raichoor, Timothée Guy Olivier Delubac, Jeffrey Newman

We present rest-frame near-ultraviolet (NUV) spectroscopy of star-forming galaxies (SFGs) at 0.6 < z < 1.2 from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) in SDSS-IV. One of the eBOSS programs is to obtain 2 ''. (about 15 kpc) fiber spect ...

Iop Publishing Ltd2015