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相关论文: Study of thorium in hypersonic gas jets: Ionizatio…

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In-source resonance ionization spectroscopy was used to identify an efficient and selective three step excitation/ionization scheme of thorium, suitable for titanium:sapphire (Ti:sa) lasers. The measurements were carried out in preparation…

Using resonant two-step laser excitation of trapped 232Th+ ions, we observe 43 previously unknown energy levels within the energy range from 7.3 to 8.3 eV. The high density of states promises a strongly enhanced electronic bridge excitation…

原子物理 · 物理学 2013-08-01 O. A. Herrera-Sancho , N. Nemitz , M. V. Okhapkin , E. Peik

Precision optical spectroscopy of exotic ions reveals accurate information about nuclear properties such as charge radii and magnetic and quadrupole moments. Thorium ions exhibit unique nuclear properties with high relevance for testing…

We present a comprehensive theoretical investigation of hyperfine-resolved excitation and detection of the low-energy isomeric state of $^{229}$Th in trapped $^{229}\mathrm{Th}^{3+}$ ions. Using a quantum master equation approach, we…

原子物理 · 物理学 2026-05-01 Wu Wang , Ke Zhang , Ke-Mi Xu , Shan-Gui Zhou

High-lying Rydberg and autoionizing (AI) states of thorium (Th) have been studied via resonance laser ionization spectroscopy at both TRIUMF Canada's particle accelerator centre and Oak Ridge National Lab (ORNL). Multiple Rydberg series…

原子物理 · 物理学 2025-08-12 Ruohong Li , Yuan Liu , Dan W. Stracener , Jens Lassen

The ionization quenching factor, the fraction of an ion's initial kinetic energy lost through ionization in a medium, was measured for H$_2^+$ and He$^+$ ions within the 2.5-5 keV energy range in an Ar/CO$_2$ gas mixture at pressures…

We propose a laser resonance chromatography (LRC) experiment on $^{229}$Th$^{3+}$, with the goal of detecting the ion's electronic ground $5f$ $^2$F$_{5/2}$ state and metastable $7s$ $^2$S$_{1/2}$ state by means of their ion mobilities. To…

Experiments on one- and two-photon laser excitation of 232Th+ ions in a radiofrequency ion trap are reported. As the first excitation step, the strongest resonance line at 402 nm from the 6d^2 7s J=3/2 ground state to the 6d7s7p J=5/2 state…

In the whole landscape of atomic nuclei, $^{229}$Th is currently the only known nucleus which could allow for the development of a nuclear-based frequency standard, as it possesses an isomeric state of just 7.6 eV energy above the ground…

仪器与探测器 · 物理学 2017-11-01 Lars von der Wense , Benedict Seiferle , Mustapha Laatiaoui , Peter G. Thirolf

[Background:] A significant quenching of high energy jets was observed in the heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) facility, and is now confirmed at the Large Hadron Collider (LHC) facility. The RHIC plus LHC…

核理论 · 物理学 2014-02-05 Xilin Zhang , Jinfeng Liao

$^{229}$Th is the only known nucleus with an excited state that offers the possibility for a direct laser excitation using existing laser technology. Its excitation energy has been measured indirectly to be 7.8(5) eV ($\approx$160 nm). The…

Thorium ions and molecules, recognized for their distinctive nuclear and atomic attributes, are central to numerous trapped-ion experiments globally. Our study introduces an effective, compact source of thorium ions produced via laser…

Ions of the isomer $^{229m}$Th are a topic of high interest for the construction of a "nuclear clock" and in the field of fundamental physics for testing symmetries of nature. They can be efficiently captured in Paul traps which are ideal…

Compact and robust ion traps for thorium are enabling technology for the next generation of atomic clocks based on a low-energy isomeric transition in the thorium-229 nucleus. We aim at a laser ablation loading of single triply ionized…

原子物理 · 物理学 2020-08-14 Marcin Piotrowski , Jordan Scarabel , Mirko Lobino , Erik Streed , Stephen Gensemer

The acceleration of ions from ultra-thin foils has been investigated using 250 TW, sub-ps laser pulses, focused on target at intensities up to $3\times10^{20} \Wcm2$. The ion spectra show the appearance of narrow band features for proton…

It has been recently predicted theoretically that due to nuclear motion light and heavy hydrogen molecules exposed to strong electric field should exhibit substantially different tunneling ionization rates (O.I. Tolstikhin, H.J. Worner and…

原子物理 · 物理学 2016-08-24 X. Wang , H. Xu , A. Atia-Tul-Noor , B. T. Hu , D. Kielpinski , R. T. Sang , I. V. Litvinyuk

We present an analysis of the kinematics and physical properties of the Class I driven jet HH46-47 based on IR medium and low resolution spectroscopy obtained with ISAAC on VLT. Our aim is to study the gas physics as a function of the…

太阳与恒星天体物理 · 物理学 2015-05-14 Rebeca Garcia Lopez , Brunella Nisini , Jochen Eisloeffel , Teresa Giannini , Francesca Bacciotti , Linda Podio

The oxygen-bearing molecular ions OH+, H2O+, and H3O+ are key species that probe the ionization rate of (partially) molecular gas that is ionized by X-rays and cosmic rays permeating the interstellar medium. We report Herschel far-infrared…

We theoretically study multiphoton ionization of Mg in the circularly as well as the linearly polarized laser fields. Specifically two-, three-, and four-photon ionization cross sections from the ground and first excited states are…

原子物理 · 物理学 2013-03-07 Gabriela Buica , Takashi Nakajima

Very little information has been so far gathered on atomic jets from young embedded low mass sources (class I stars), especially in the inner jet region. We exploit multiwave spectroscopic observations to infer physical conditions of the…

太阳与恒星天体物理 · 物理学 2016-11-02 B. Nisini , T. Giannini , S. Antoniucci , J. M. Alcala' , F. Bacciotti , L. Podio
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