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Search Publications by: Joseph N. Tan (Fed)

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Displaying 1 - 25 of 132

High resolution X-ray Spectra of the Time Evolution of Emission from Metastable Electronic States of Highly Charged Ni-like Ions

June 25, 2024
Author(s)
Timothy Burke, Endre Takacs, Dipti Dipti, Adam Hosier, Galen O'Neil, Hunter Staiger, Joseph N. Tan, Aung S. Naing, Joan Marler, Yuri Ralchenko
Metastable levels of highly charged ions that can only decay via highly forbidden transitions can have a significant effect on the properties of high temperature plasmas. For example the highly forbidden 3d10 J=0 - 3d94s ( 5 2 , 1 2 )J=3 magnetic octupole

Observations and identifications of extreme ultraviolet spectra of Ca-like to Na-like neodymium ions using an electron beam ion trap

August 23, 2023
Author(s)
Yang Yang, Dipti Dipti, Chihiro Suzukic, A. C. Gall, R. Silwal, Samuel Sanders, Joseph N. Tan, Aung S. Naing, Endre Takacs, Yuri Ralchenko
Extreme ultraviolet (EUV) radiation from M-shell Ca-like, Nd40+, through Nalike, Nd49+, highly charged ions have been measured at an electron beam ion trap (EBIT) facility at the National Institute of Standards and Technology. To produce the ionization

Determination of electron beam energy in measuring the electron-impact ionization cross section of He-like Fe24+

March 17, 2023
Author(s)
Yuri Ralchenko, Galen O'Neil, Paul Szypryt, Joseph N. Tan, Aung S. Naing, Yang Yang, Dipti Dipti, Amy Gall, Adam Hosier, David Schultz, Randall Smith, Nancy Brickhouse, Endre Takacs
In an effort to measure electron-impact ionization (EII) cross sections of He-like $Fe^24+}$ at the electron beam ion trap (EBIT) facility of the National Institute of Standards and Technology (NIST), we have experimentally determined the corrections to

Background and blended spectral line reduction in precision spectroscopy of EUV and x-ray transitions in highly charged ions

March 3, 2023
Author(s)
Yuri Ralchenko, Joseph N. Tan, Aung S. Naing, Galen O'Neil, Paul Szypryt, Dipti Dipti, Grant Mondeel, Roshani Silwal, Alain Lapierre, Steven Blundell, Gerald Gwinner, Antonio Camargo Villari, Endre Takacs
We report a method in EBIT spectral analysis that reduces signal from contaminant lines of 1 known or unknown origin. We utilize similar ion charge distributions of heavy highly charged ions 2 that create similar potentials for lighter contaminating

Analysis of E3 Transitions in Ag-like High-Z Ions Observed with the NIST EBIT

March 1, 2023
Author(s)
Yuri Ralchenko, David La Mantia, Aung S. Naing, Paul Szypryt, Joseph N. Tan, Endre Takacs, Dipti Dipti, Yang Yang, Adam Hosier, Hunter Staiger
We report measurements and identification of the E3 4f$_7/2,5/2}$-5s$_1⁄2$ transitions and E1 allowed transitions in Ag-like W (Z=74), Re (Z=75), and Ir (Z=77). The spectra were recorded at the NIST EBIT using a grazing-incidence EUV spectrometer. The

Identifications of extreme ultraviolet spectra of Br-like to Ni-like neodymium ions using an electronbeam ion trap

April 30, 2021
Author(s)
C. Suzuki, Dipti Goyal, Y. Yang, A. Gall, Roshani Silwal, S. Sanders, Aung S. Naing, Joseph N. Tan, Endre A. Takacs, Yuri Ralchenko
Charge-resolved extreme ultraviolet spectra of open N-shell neodymium (Nd) ions have been recorded in an electron beam ion trap facility at the National Institute of Standards and Technology. The measurements have been performed for nominal electron beam

Measurement of the 2P1/2-2P3/2 fine structure splitting in fluorine-like Kr, W, Re, Os and Ir

September 2, 2020
Author(s)
Galen O'Neil, Samuel C. Sanders, Paul Szypryt, Dipti Goyal, Amy Gall, Yang Yang, Samuel M. Brewer, W.Bertrand (Randy) Doriese, Joseph Fowler, Daniel Swetz, Joseph N. Tan, Joel Ullom, Andrey V. Volotka, Endre Takacs, Yuri Ralchenko
Quantum electrodynamics (QED) is currently considered to be one of the most accurate theories of fundamental interactions. As its extraordinary precision offers unique scientific opportunities, e.g., search for new physics, stringent experimental tests of

A transition-edge sensor-based x-ray spectrometer for the study of highly charged ions at the National Institute of Standards and Technology electron beam ion trap

December 16, 2019
Author(s)
Paul Szypryt, Galen C. O'Neil, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Douglas A. Bennett, William B. Doriese, Malcolm S. Durkin, Joseph W. Fowler, Johnathon D. Gard, Gene C. Hilton, Kelsey M. Morgan, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom, Yuri Ralchenko
We report on the design, commissioning, and initial measurements of a Transition-Edge Sensor (TES) x-ray spectrometer for the Electron Beam Ion Trap (EBIT) at the National Institute of Standards and Technology (NIST). Over the past few decades, the NIST

On Low-Energy Tail Distortions in the Detector Response Function of X-Ray Microcalorimeter Spectrometers

November 21, 2019
Author(s)
Galen C. O'Neil, Paul Szypryt, Endre Takacs, Joseph N. Tan, Sean W. Buechele, Aung Naing, Young I. Joe, Daniel S. Swetz, Daniel R. Schmidt, William B. Doriese, Johnathon D. Gard, Carl D. Reintsema, Joel N. Ullom, John S. Villarrubia, Yuri Ralchenko
We use narrow spectral lines from the X-ray spectra of various highly charged ions to measure low-energy tail-like deviations from a Gaussian response function in a microcalorimeter X-ray spectrometer with Au absorbers at energies from 650 to 3320 eV. We

Capture of Highly Charged Ions in a Pseudo-Hyperbolic Paul Trap

July 12, 2019
Author(s)
Joan M. Dreiling, Aung S. Naing, Joseph N. Tan, Joshua Hanson, Shannon Hoogerheide, Samuel M. Brewer
The confinement of ions in a radio-frequency (RF) trap (also known as a Paul trap) has proven to be advantageous in many applications. Typically, singly- or few-times-ionized atoms can be created in situ within the ion trap. Highly charged ions, on the

Lifetime of the metastable 2 P 1/2 state of F-like Ar 9+ isolated in a compact Penning trap

September 6, 2018
Author(s)
Samuel M. Brewer, Joan M. Dreiling, Nicholas D. Guise, Shannon M. Hoogerheide, Aung Naing, Joseph N. Tan
Multiple-ionized atoms can be captured at low energy in a compact Penning trap, allowing the isolation of a single charge state to measure the radiative lifetime of an atomic state that decays via weakly allowed transitions. Such a measurement is reported

Experiments with highly-ionized atoms in unitary Penning traps

August 14, 2015
Author(s)
Shannon Hoogerheide, Aung Naing, Joan M. Dreiling, Samuel M. Brewer, Nicholas D. Guise, Joseph N. Tan
Highly-ionized atoms with special properties have been proposed for interesting applications, including potential candidates for a new generation of optical atomic-clocks at the 1 part in 1019 level of precision, quantum-information processing, and tests

A Miniature EBIT with Ion Extraction for Isolating Highly Charged Ions

May 28, 2015
Author(s)
Shannon Hoogerheide, Joseph N. Tan
We report on the development of a room-temperature miniature electron beam ion trap (EBIT) for efficient production of charge states with relatively low ionization energies. A unitary Penning trap is modified slightly to provide the magnetic field and

Multiply-ionized Atoms Isolated at low energy in a Unitary Penning Trap

January 9, 2015
Author(s)
Joseph N. Tan, Shannon Hoogerheide, Samuel M. Brewer, Nicholas D. Guise
Ions extracted from the EBIT at NIST are slowed and captured in a Penning trap that is made very compact ( 150 cm3) by a unitary architecture. Measurements after 1 ms of ion storage indicate that the captured ions are distributed with 5(1) eV of energy