A5079122326- Atomic and Molecular Physics
- Astrophysics and Star Formation Studies
- Advanced Chemical Physics Studies
- Fullerene Chemistry and Applications
- Atmospheric Ozone and Climate
- Mass Spectrometry Techniques and Applications
- Laser-induced spectroscopy and plasma
- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Integrated Circuits and Semiconductor Failure Analysis
- Diamond and Carbon-based Materials Research
- Organic Chemistry Cycloaddition Reactions
- Ion-surface interactions and analysis
- Silicon and Solar Cell Technologies
- Atmospheric chemistry and aerosols
- Spectroscopy and Quantum Chemical Studies
- Synthesis and Properties of Aromatic Compounds
- Advanced Combustion Engine Technologies
- Solid-state spectroscopy and crystallography
- Photochemistry and Electron Transfer Studies
- Molecular Spectroscopy and Structure
- Molecular spectroscopy and chirality
- Thermal Radiation and Cooling Technologies
- Quantum optics and atomic interactions
- Semiconductor materials and interfaces
Stockholm University
2022-2024
University of Gothenburg
2022
Universidad Nacional Autónoma de México
2020
Abstract After decades of searching, astronomers have recently identified specific Polycyclic Aromatic Hydrocarbons (PAHs) in space. Remarkably, the observed abundance cyanonaphthalene (CNN, C 10 H 7 CN) Taurus Molecular Cloud (TMC-1) is six orders magnitude higher than expected from astrophysical modeling. Here, we report unimolecular dissociation and radiative cooling rate coefficients 1-CNN isomer its cationic form. These results are based on measurements time-dependent neutral product...
Naphthalene and azulene are isomeric polycyclic aromatic hydrocarbons (PAHs) topical in the context of astrochemistry due to recent discovery substituted naphthalenes Taurus Molecular Cloud-1 (TMC-1). Here, thermal- photo-induced isomerization, dissociation, radiative cooling dynamics energized (vibrationally hot) naphthalene (Np+) (Az+) radical cations, occurring over microsecond seconds timescale, investigated using a cryogenic electrostatic ion storage ring, affording “molecular cloud...
Several small Polycyclic Aromatic Hydrocarbons (PAHs) have been identified recently in the Taurus Molecular Cloud (TMC-1) using radio telescope observations. Reproducing observed abundances of these molecules has a challenge for astrochemical models. Rapid radiative cooling PAHs by Recurrent Fluorescence (RF), emission optical photons from thermally populated electronically excited states, shown to efficiently stabilize following ionization, augmenting their resilience astronomical...
Negative ions are unique quantum systems where electron correlation plays a decisive role in determining their properties. The lack of optically allowed transitions prevents traditional optical spectroscopy and the affinity is, therefore, for most elements, only atomic quantity that can be determined with high accuracy. In this work, we present high-precision experimental determination cesium. A collinear laser-ion beam apparatus was used to investigate partial photodetachment cross section...
Abstract Negative ions, which are formed when an electron is attached to a neutral system, unique quantum systems. The lack of long-range Coulomb force causes the inter-electronic interactions become relatively more important. As consequence, independent particle model, adequately describes atomic structure under normal conditions, breaks down. alkali negative with closed valence s -shell, among simplest anionic Hence, they can favorably be used benchmark theory. In this work, we have...
Polycyclic aromatic hydrocarbons have widely been conjectured to be ubiquitous in space, as supported by the recent discovery of two isomers cyanonaphthalene, indene, and 2-cyanoindene Taurus molecular cloud-1 using radioastronomy. Here, photoionization dynamics 1-cyanonaphthalene (1-CNN) are investigated synchrotron radiation over hν = 9.0-19.5 eV range, revealing that prompt autoionization from plasmon resonance dominates photophysics for 11.5-16.0 eV. Minimal photo-induced dissociation,...
We have measured recurrent fluorescence (RF) cooling rates of internally hot tetracene cations, C18H12+, as functions their storage times and internal energies in two different electrostatic ion-beam rings - the cryogenic ring DESIREE with a circumference 8.6 meters Stockholm much smaller room temperature Mini-Ring Lyon, which has 0.71 meters. The RF were to be high 150 1000 s-1 for 7 9.4 eV energy range, where we probed time evolution distribution nanosecond laser pulses 1 kHz repetition...
In this paper, we present an apparatus for studies into the photodetachment process of atomic negative ions. State-selective detection residual atom following initial step is achieved by combining resonant laser excitation photo-detached with electric field ionization. The resonance ionization technique in combination a co-linear ion-laser beam geometry gives experimental that has both high selectivity and sensitivity. addition to measurements single selected partial channel, also can be...
Time-dependent photodetachment action spectra for the linear hydrocarbon anions C4H- and C6H- are investigated using cryogenic Double ElectroStatic Ion Ring ExpEriment. The radiative cooling characteristics of these ions on millisecond to seconds timescale characterized by monitoring changes in their as cool spontaneous infrared (IR) emission. average rates, extracted Non-negative Matrix Factorization, fit with 1/e lifetimes 19 ± 2 3.0 0.2 s C6H-, respectively. rates successfully reproduced...
We have studied the stability of C$_{59}$ anions as a function time, from their formation on femtosecond timescales to stabilization second and beyond, using combination theory experiments. The C$_{59}^-$ fragments were produced in collisions between C$_{60}$ fullerene neutral helium gas at velocity 90 km/s (corresponding collision energy 166 eV center-of-mass frame). then stored cryogenic ion-beam storage ring DESIREE facility where they followed for up one minute. Classical molecular...
Abstract We have studied the stability of C 59 anions as a function time, from their formation on femtosecond timescales to stabilization second and beyond, using combination theory experiments. The <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi mathvariant="normal">C</mml:mi> </mml:mrow> <mml:mn>59</mml:mn> <mml:mo>−</mml:mo> </mml:msubsup> </mml:math> fragments were produced in collisions between 60 fullerene neutral helium gas...
High-precision measurements of the electron affinities (EA) three stable isotopes silicon, $^{28}$Si, $^{29}$Si and $^{30}$Si, have been performed at cryogenic electrostatic ion-beam storage ring DESIREE. The quantum states ions were manipulated using laser depletion, photodetached by photodetachment threshold spectroscopy. These EA values are first reported for $^{29}$Si$^-$ $^{30}$Si$^-$ provide a reduced uncertainty $^{28}$Si$^-$. resulting EAs $EA(^{28}$Si$) = 1.38952201(17)$ eV,...
The radiative decay of excited states the negative ion rhodium, Rh$^-$, has been investigated experimentally and theoretically. experiments were conducted at Double ElectroStatic Ion Ring Experiment (DESIREE) facility Stockholm University using selective photodetachment from a stored beam to monitor time evolution state populations. lifetimes Rh$^-$ $^3F_{3}$ $^3F_{2}$ fine structure levels measured be 3.2(6)~s 21(4)~s, respectively. An additional, previously unreported, higher-lying bound...
Radiative lifetimes of three elements the nitrogen group have been experimentally investigated at Double ElectroStatic Ion Ring Experiment (DESIREE) facility Stockholm University. The experiments were performed through selective laser photodetachment excited states P$^-$, As$^-$ and Sb$^-$ ions stored in a cryogenic storage ring. experimental results compared with theoretically predicted lifetimes, yielding mixture very good agreements some cases large discrepancies others. These are part...
After decades of speculation and searching, astronomers have recently identified specific Polycyclic Aromatic Hydrocarbons (PAHs) in space. Remarkably, the observed abundance cyanonaphthalene (CNN, C10H7CN) Taurus Molecular Cloud (TMC-1) is six orders magnitude higher than expected from astrophysical modeling. Here, we report absolute unimolecular dissociation radiative cooling rate coefficients 1-CNN isomer its cationic form. These results are based on measurements time-dependent neutral...
Synopsis A refined Resonant Ionization Spectroscopy (RIS) scheme for high resolution Laser Photodetachment Threshold (LPTS). In this work the is used to measure electron affinity of cesium.