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← Dr. Andree Welker

Evidence-backed archive

Full Research Record

A structured record of work spanning CALICE detector electronics, CERN ISOLDE and ISOLTRAP mass spectrometry, nuclear structure, antimatter instrumentation, research proposals, and technical reports.

53 records

Peer-reviewed publication·2020Source verified

Multiferroic bismuth ferrite: Perturbed angular correlation studies on its ferroic α−β phase transition

Physical Review B 102, 224110

Perturbed angular correlation study of the ferroic α−β phase transition in multiferroic bismuth ferrite (PRB 102, 224110).

Materials physicsHyperfine interactions
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Peer-reviewed publication·2020Source verified

Laser-assisted decay spectroscopy and mass spectrometry of 178Au

Physical Review C 102, 044332

Combined laser-assisted decay spectroscopy and mass spectrometry of ¹⁷⁸Au (PRC 102, 044332).

Nuclear physicsCERNISOLDELaser spectroscopy
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Peer-reviewed publication·2020Source verified

Restoring the valence-shell stabilization in 140Nd

Physical Review C 102, 041304

Nuclear-structure study on restoring valence-shell stabilization in ¹⁴⁰Nd (PRC 102, 041304).

Nuclear physicsNuclear structure
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Peer-reviewed publication·2020Source link pending

Positron production using a 9 MeV electron linac for the GBAR experiment

Nuclear Instruments and Methods in Physics Research A 985, 164657

Describes positron production with a 9 MeV electron linac for the GBAR antimatter experiment.

Antimatter physicsGBARAccelerator technologyCERN
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Peer-reviewed publication·2020Source verified

Laser-assisted decay spectroscopy for the ground states of 180,182Au

Physical Review C 102, 024312

Laser-assisted decay spectroscopy of the ground states of ¹⁸⁰,¹⁸²Au (PRC 102, 024312).

Nuclear physicsCERNISOLDELaser spectroscopy
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Peer-reviewed publication·2020Source link pending

Masses of short-lived 49Sc, 50Sc, 70As, 73Br and stable 196Hg nuclides

Nuclear Physics A 1002, 121990

Reports masses of short-lived ⁴⁹Sc, ⁵⁰Sc, ⁷⁰As, ⁷³Br and stable ¹⁹⁶Hg nuclides.

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2020Source verified

Examining the N = 28 shell closure through high-precision mass measurements of 46–48Ar

Physical Review C 102, 014301

High-precision mass measurements of ⁴⁶–⁴⁸Ar used to examine the N=28 shell closure (PRC 102, 014301).

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2020Source verified

Shape coexistence in 187Au studied by laser spectroscopy

Physical Review C 101, 064321

Laser-spectroscopy investigation of shape coexistence in ¹⁸⁷Au (PRC 101, 064321).

Nuclear physicsCERNISOLDELaser spectroscopy
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Conference proceeding·2020Source link pending

Coulomb Excitation of Proton-rich N = 80 Isotones at HIE-ISOLDE

Journal of Physics: Conference Series 1555, 012027

Coulomb-excitation study of proton-rich N=80 isotones at HIE-ISOLDE.

Nuclear physicsCERNISOLDECoulomb excitation
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Peer-reviewed publication·2020Source verified

Hyperfine anomaly in gold and magnetic moments of Iπ = 11/2− gold isomers

Physical Review C 101, 034308

Laser-spectroscopy determination of hyperfine anomaly and magnetic moments of Iπ=11/2⁻ gold isomers (PRC 101, 034308).

Nuclear physicsCERNISOLDELaser spectroscopy
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Peer-reviewed publication·2020Source verified

First Glimpse of the N = 82 Shell Closure below Z = 50 from Masses of Neutron-Rich Cadmium Isotopes and Isomers

Physical Review Letters 124, 092502

Masses of neutron-rich cadmium isotopes and isomers providing a first glimpse of the N=82 shell closure below Z=50 (PRL 124, 092502).

Nuclear physicsCERNISOLDENuclear structure
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Peer-reviewed publication·2020Source link pending

Development of a PbWO4 Detector for Single-Shot Positron Annihilation Lifetime Spectroscopy at the GBAR Experiment

Acta Physica Polonica A 137, 122–125

Development of a PbWO₄ detector for single-shot positron annihilation lifetime spectroscopy at CERN’s GBAR experiment.

Antimatter physicsGBARDetector electronicsCERN
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Peer-reviewed publication·2020Source link pending

Accumulation of Positrons from a LINAC Based Source

Acta Physica Polonica A 137, 164–166

Reports positron accumulation from a LINAC-based source in the context of antimatter / GBAR beam preparation.

Antimatter physicsGBARAccelerator technologyCERN
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Peer-reviewed publication·2019Source link pending

A hyperfine look at titanium dioxide

AIP Advances 9, 085208

Hyperfine-interaction study of titanium dioxide, probing local electronic/structural environments.

Materials physicsHyperfine interactions
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Peer-reviewed publication·2019Source verified

QEC-value determination for 21Na→21Ne and 23Mg→23Na mirror-nuclei decays using high-precision mass spectrometry with ISOLTRAP

Physical Review C 100, 015502

Determines Q_EC values for the ²¹Na→²¹Ne and ²³Mg→²³Na mirror decays with ISOLTRAP high-precision mass spectrometry (PRC 100, 015502).

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2019Source verified

Mass measurements of neutron-rich isotopes near N=20 by in-trap decay with the ISOLTRAP spectrometer

Physical Review C 100, 014304

Mass measurements of neutron-rich isotopes near N=20 using in-trap decay at ISOLTRAP (PRC 100, 014304).

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2019Source link pending

Evaluation of high-precision atomic masses of A ∼ 50–80 and rare-earth nuclides measured with ISOLTRAP

European Physical Journal A 55, 96

Evaluation and compilation of high-precision ISOLTRAP atomic masses for A∼50–80 and rare-earth nuclides.

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2019Source link pending

Direct decay-energy measurement as a route to the neutrino mass

Hyperfine Interactions 240, 61

Discusses direct decay-energy measurement as an experimental route toward neutrino-mass determination.

Nuclear physicsCERNISOLDENeutrino mass
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Peer-reviewed publication·2019Source verified

Shape staggering of midshell mercury isotopes from in-source laser spectroscopy compared with density-functional-theory and Monte Carlo shell-model calculations

Physical Review C 99, 044306

Compares in-source laser-spectroscopy shape staggering of midshell mercury isotopes with DFT and Monte Carlo shell-model calculations (PRC 99, 044306).

Nuclear physicsCERNISOLDELaser spectroscopy
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Conference proceeding·2018Source link pending

Search for Isovector Valence-Shell Excitations in 140Nd and 142Sm via Coulomb excitation reactions of radioactive ion beams

EPJ Web of Conferences 194, 03003

Conference contribution on searching for isovector valence-shell excitations in ¹⁴⁰Nd and ¹⁴²Sm via Coulomb excitation of radioactive beams.

Nuclear physicsCERNISOLDECoulomb excitation
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Peer-reviewed publication·2018Source link pending

Change in structure between the I = 1/2 states in 181Tl and 177,179Au

Physics Letters B 786, 355

Investigates the structural change between I=1/2 states in ¹⁸¹Tl and ¹⁷⁷,¹⁷⁹Au.

Nuclear physicsCERNISOLDENuclear structure
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Peer-reviewed publication·2018Source verified

Characterization of the shape-staggering effect in mercury nuclei

Nature Physics 14, 1163

Nature Physics study characterizing shape staggering in mercury nuclei using laser-spectroscopy observables.

Nuclear physicsCERNISOLDELaser spectroscopy
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Doctoral thesis·2018Source verified

Implementation and commissioning of the phase-imaging ion-cyclotron-resonance method and mass measurements of exotic copper isotopes with ISOLTRAP

CERN / Technische Universität Dresden

Implemented and commissioned the Phase-Imaging Ion-Cyclotron-Resonance (PI-ICR) technique at CERN’s ISOLTRAP Penning-trap mass spectrometer—including the required electronics and software—for online high-precision mass spectrometry, and measured exotic neutron-rich copper isotopes—including work probing the structure of doubly magic ⁷⁸Ni from one proton away (⁷⁹Cu).

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2018Source verified

Precision Mass Measurements of 58–63Cr: Nuclear Collectivity Towards the N=40 Island of Inversion

Physical Review Letters 120, 232501

Precision mass measurements of ⁵⁸–⁶³Cr mapping nuclear collectivity toward the N=40 island of inversion (PRL 120, 232501).

Nuclear physicsCERNISOLDENuclear structure
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CERN research proposal·2018Source link pending

Collinear resonance ionization spectroscopy of RaF molecules

CERN INTC

CERN INTC proposal for collinear resonance ionization spectroscopy of RaF molecules.

Nuclear physicsCERNISOLDEMolecular spectroscopy
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Peer-reviewed publication·2017Source verified

Binding Energy of 79Cu: Probing the Structure of the Doubly Magic 78Ni from Only One Proton Away

Physical Review Letters 119, 192502

Precision mass/binding-energy measurement of ⁷⁹Cu with ISOLTRAP, probing the structure of doubly magic ⁷⁸Ni from only one proton away (PRL 119, 192502).

Nuclear physicsCERNISOLDENuclear structure
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Peer-reviewed publication·2017Source link pending

Viewpoint: Doubly Magic Nickel

Physics 10, 121

Physics Viewpoint highlighting the scientific implications of the ⁷⁹Cu / ⁷⁸Ni mass result for doubly magic nickel.

Nuclear physicsNuclear structure
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Peer-reviewed publication·2017Source verified

Spectroscopy of the long-lived excited state in neutron-deficient 195,197,199Po by precision mass measurements

Physical Review C 96, 044325

Precision mass spectrometry of neutron-deficient ¹⁹⁵,¹⁹⁷,¹⁹⁹Po to characterize a long-lived excited state (PRC 96, 044325).

Nuclear physicsCERNISOLDENuclear spectroscopy
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Peer-reviewed publication·2017Source link pending

Precision electron-capture energy in 202Pb and its relevance for neutrino mass determination

European Physical Journal A 53, 153

Precision determination of the electron-capture energy in ²⁰²Pb and discussion of its relevance for neutrino-mass determination.

Nuclear physicsCERNISOLDENeutrino mass
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Peer-reviewed publication·2017Source verified

Nuclear deformation in the A≈100 region: Comparison between new masses and mean-field predictions

Physical Review C 96, 014310

Compares new precision masses in the A≈100 region with mean-field predictions to assess nuclear deformation trends (PRC 96, 014310).

Nuclear physicsCERNISOLDENuclear structure
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CERN research proposal·2017Source link pending

Search for β-transitions with the lowest decay energy for a determination of the neutrino mass: precision Q-value measurements of 159Dy and 175Hf

CERN INTC

CERN INTC proposal for precision Q-value measurements of ¹⁵⁹Dy and ¹⁷⁵Hf toward neutrino-mass determination.

Nuclear physicsCERNISOLDENeutrino mass
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CERN research proposal·2017Source link pending

QEC value determination of the superallowed beta-decay of 70Br

CERN INTC

CERN INTC proposal to determine the Q_EC value of the superallowed β-decay of ⁷⁰Br.

Nuclear physicsCERNISOLDEWeak interaction
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Peer-reviewed publication·2017Source link pending

Extending and refining the nuclear mass surface with ISOLTRAP

Journal of Physics G 44

Overview of ISOLTRAP results that extend and refine the nuclear mass surface across regions relevant to nuclear structure and astrophysics.

Nuclear physicsCERNISOLDEMass spectrometry
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Technical report·2017Source verified

First online application of the Phase-Imaging Ion-Cyclotron-Resonance technique at ISOLTRAP

ISOLDE Newsletter

ISOLDE Newsletter report on the first online application of the PI-ICR technique at ISOLTRAP.

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2017Source link pending

Precision Mass Measurements with ISOLTRAP to Study the Evolution of the N = 82 Shell Gap far from Stability

CERN INTC

Addendum to the ISOLTRAP N=82 shell-gap mass-measurement programme at CERN INTC.

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2016Source link pending

Penning-trap mass measurements of Zn and Cu isotopes relevant for the astrophysical rp-process

CERN INTC

CERN INTC letter of intent for Penning-trap mass measurements of Zn and Cu isotopes relevant to the astrophysical rp-process.

Nuclear physicsCERNISOLDENuclear astrophysics
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Peer-reviewed publication·2016Source link pending

Background-free beta-decay half-life measurements by in-trap decay and high-resolution MR-ToF mass analysis

Nuclear Instruments and Methods in Physics Research B 376, 275

Method paper on background-free β-decay half-life measurements using in-trap decay combined with high-resolution MR-ToF mass analysis.

Nuclear physicsCERNISOLDEBeta decay
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CERN research proposal·2016Source link pending

IS490: Seeking the onset of collectivity in neutron-rich krypton isotopes with ISOLTRAP

CERN INTC

CERN INTC addendum (IS490) seeking the onset of collectivity in neutron-rich krypton isotopes with ISOLTRAP.

Nuclear physicsCERNISOLDEMass spectrometry
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Technical report·2016Source verified

Mass spectrometry of neutron-rich copper isotopes: a view of 78Ni from only one proton away

ISOLDE Newsletter

ISOLDE Newsletter report on mass spectrometry of neutron-rich copper isotopes as a view of ⁷⁸Ni from one proton away.

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2016Source link pending

Mass spectrometry of neutron-rich chromium isotopes into the N = 40 island of inversion

CERN INTC

CERN INTC proposal for mass spectrometry of neutron-rich chromium isotopes into the N=40 island of inversion.

Nuclear physicsCERNISOLDEMass spectrometry
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Peer-reviewed publication·2015Source verified

Precision Mass Measurements of 129–131Cd and Their Impact on Stellar Nucleosynthesis via the Rapid Neutron Capture Process

Physical Review Letters 115, 232501

High-precision ISOLTRAP mass measurements of ¹²⁹–¹³¹Cd used to constrain stellar nucleosynthesis via the rapid neutron-capture (r) process (PRL 115, 232501).

Nuclear physicsCERNISOLDENuclear astrophysics
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Peer-reviewed publication·2015Source link pending

Towards ultrahigh-resolution multi-reflection time-of-flight mass spectrometry at ISOLTRAP

Physica Scripta T166

Reports progress toward ultrahigh-resolution multi-reflection time-of-flight (MR-ToF) mass spectrometry at ISOLTRAP for improved isobar and isomer separation.

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2015Source link pending

Shape-coexistence and shape-evolution studies for bismuth isotopes by in-source laser spectroscopy and beta-delayed fission in 188Bi

CERN INTC

CERN INTC proposal on shape coexistence/evolution in bismuth isotopes via in-source laser spectroscopy and β-delayed fission in ¹⁸⁸Bi.

Nuclear physicsCERNISOLDELaser spectroscopy
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CERN research proposal·2014Source verified

In-source laser spectroscopy of mercury isotopes

CERN INTC

CERN INTC proposal (INTC-P-424) for in-source laser spectroscopy of mercury isotopes.

Nuclear physicsCERNISOLDELaser spectroscopy
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CERN research proposal·2014Source verified

Search for β-transitions with the lowest decay energy for a determination of the neutrino mass

CERN INTC

CERN INTC proposal (INTC-P-410) to search for β-transitions with the lowest decay energy for neutrino-mass determination.

Nuclear physicsCERNISOLDENeutrino mass
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CERN research proposal·2014Source verified

High precision mass measurements of odd-odd T=1 nuclides for the study of the Isobaric Multiplet Mass Equation

CERN INTC

CERN INTC letter of intent (INTC-I-157) for high-precision mass measurements of odd-odd T=1 nuclides to study the Isobaric Multiplet Mass Equation.

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2014Source link pending

Beta-delayed fission, laser spectroscopy and shape-coexistence studies with astatine beams

CERN INTC

CERN INTC proposal on β-delayed fission, laser spectroscopy, and shape-coexistence studies with astatine beams.

Nuclear physicsCERNISOLDELaser spectroscopy
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CERN research proposal·2014Source link pending

Seeking the Purported Magic Number N = 32 with High-Precision Mass Spectrometry

CERN INTC

CERN INTC proposal seeking the purported magic number N=32 with high-precision mass spectrometry.

Nuclear physicsCERNISOLDEMass spectrometry
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Technical report·2014Source verified

Report to the ISOLDE and Neutron Time-of-Flight Committee: Penning-trap mass measurements with ISOLTRAP

CERN INTC

Status report to the CERN INTC on Penning-trap mass measurements performed with ISOLTRAP (INTC-SR-034).

Nuclear physicsCERNISOLDEMass spectrometry
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CERN research proposal·2013Source verified

Precision mass measurements with ISOLTRAP to study the evolution of the N=82 shell gap far from stability

CERN ISOLDE and Neutron Time-of-Flight Committee

CERN INTC proposal (INTC-P-382) for ISOLTRAP precision mass measurements to study the evolution of the N=82 shell gap far from stability.

Nuclear physicsCERNISOLDEMass spectrometry
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Diploma thesis·2013Source link pending

Readout chain for high-resolution hadronic calorimeters with silicon photomultipliers

Johannes Gutenberg University Mainz — ATLAS Group / CALICE / ILC

Compressed one-year end-to-end particle/detector-physics delivery of a 1 m, 12-layer PCB Link Data Aggregator (LDA): full design, population, external manufacture, FPGA firmware, first beamtime, and data analysis—built on Delphi electronics/PCB/programming foundations and university minors in electronics, computer science, nuclear chemistry and mathematics. This work provided the foundation for the subsequent direct transition into nuclear-physics doctoral research.

High-energy physicsElectronicsFPGACalorimetry
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Technical report·2013Source verified

The International Linear Collider Technical Design Report — Volume 2: Physics

International Linear Collider Collaboration

Listed signatory as A. Welker with affiliation 138, Johannes Gutenberg University Mainz, on the ILC Technical Design Report (Physics volume).

International Linear ColliderHigh-energy physicsParticle physicsHiggs physics
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Conference proceeding·2012Source verified

Calorimetry for Lepton Collider Experiments — CALICE results and activities

CALICE Collaboration

CALICE collaboration report on calorimetry results and activities for lepton-collider experiments, covering highly granular calorimeter R&D relevant to future e⁺e⁻ machines.

High-energy physicsCalorimetryDetector electronics
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