Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Decays of excited silver-cluster anions Ag-n, n=4 to 7, in the Double ElectroStatic Ion Ring ExpEriment
Stockholm University, Faculty of Science, Department of Physics.
Stockholm University, Faculty of Science, Department of Physics. Jan Kochanowski University, Poland.
Stockholm University, Faculty of Science, Department of Physics.
Stockholm University, Faculty of Science, Department of Physics.
Show others and affiliations
Number of Authors: 92018 (English)In: Physical Review A: covering atomic, molecular, and optical physics and quantum information, ISSN 2469-9926, E-ISSN 2469-9934, Vol. 98, no 2, article id 022705Article in journal (Refereed) Published
Abstract [en]

Spontaneous decays of small, hot silver-cluster anions Ag-n(-), n = 4-7, have been studied using one of the rings of the Double ElectroStatic Ion Ring ExpEriment (DESIREE). Observation of these decays over very long time scales is possible due to the very low residual gas pressure (similar to 10(-14)) and cryogenic (13 K) operation of DESIREE. The yield of neutral particles from stored beams of Ag-6(-) and Ag-2(-) anions were measured for 100 milliseconds and were found to follow single power-law behavior with millisecond time-scale exponential cutoffs. The Ag-4(-) and Ag-5(-) anions were stored for 60 s and the observed decays show two-component power-law behaviors. We present calculations of the rate constants for electron detachment from and fragmentation of Ag-4(-) and Ag-5(-). In these calculations, we assume that the internal energy distribution of the clusters are flat and with this we reproduce the early steep parts of the experimentally measured decay curves for Ag-4(-) and Ag-5(-) which extends to tens and hundreds of milliseconds, respectively. The fact that the calculations reproduce the early slopes of Ag-4(-) and Ag-5(-), which differ for the two cases, suggests that it is the changes in fragmentation rates with internal cluster energies of Ag-4(-) and Ag-5(-) rather than conditions in the ion source that determine this behavior. Comparisons with the measurements strongly suggest that the neutral particles detected in these time domains originate from Ag-4(-) -> Ag-3(-) + Ag and Ag-5(-) -> Ag-3(-) +Ag-2 fragmentation processes.

Place, publisher, year, edition, pages
2018. Vol. 98, no 2, article id 022705
National Category
Physical Sciences
Research subject
Physics
Identifiers
URN: urn:nbn:se:su:diva-160075DOI: 10.1103/PhysRevA.98.022705ISI: 000442804000005OAI: oai:DiVA.org:su-160075DiVA, id: diva2:1251829
Available from: 2018-09-28 Created: 2018-09-28 Last updated: 2019-12-04Bibliographically approved
In thesis
1. DESIREE: Instrumentation Developments and Hot Metal Cluster Decays
Open this publication in new window or tab >>DESIREE: Instrumentation Developments and Hot Metal Cluster Decays
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This thesis presents instrumentation developments and measurements performed at the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. DESIREE operates at cryogenic temperatures ~13 K, with very low background pressures of ~10-14mbar, allowing the observation of stored ions to long times of tens of seconds and longer.

Investigations into improving the count rate capability of the DESIREE detectors are presented. Microchannel plate (MCP) detectors are used for position sensitive particle counting in the DESIREE detector assemblies. In a cryogenic environment the operational resistance of MCPs is orders of magnitude higher than at room temperature and this limits the possible count rates. Novel low-resistance MCP detectors were investigated and resulted in the replacement of the MCPs in the DESIREE detector assemblies.

DESIREE was used to measure spontaneous decays of hot, small cluster anions. The decays of small silver, copper and gold cluster anions are presented and compared to statistical model calculations. An experiment that is able to measure the proportion of spontaneous decay due to fragmentation or electron detachment in dimer anions of silver and copper is presented and significant, previously overlooked, contributions from electron detachment to the decay is identified. Furthermore, measurements of the stability and decay of small carbon cluster dianions are presented. These experiments utilised the aforementioned low-resistance MCPs.

Place, publisher, year, edition, pages
Stockholm: Department of Physics, Stockholm University, 2019. p. 84
Keywords
DESIREE, microchannel plate, clusters, spontaneous decay, small metal cluster anions, silver, copper, gold, carbon dianions, fragmentation, vibrational autodetachment, DESIREE, mikrokanalplattor, kluster, spontana sönderfall, små metallklusteranjoner, silver, koppar, guld, kol di-anjoner, fragmentering
National Category
Physical Sciences
Research subject
Physics
Identifiers
urn:nbn:se:su:diva-167321 (URN)978-91-7797-634-9 (ISBN)978-91-7797-635-6 (ISBN)
Public defence
2019-05-10, FP41, hus 1, AlbaNova universitetscentrum, Roslagstullbacken 21, Stockholm, 13:00 (English)
Opponent
Supervisors
Note

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 3: Manuscript.

Available from: 2019-04-15 Created: 2019-03-25 Last updated: 2019-05-03Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Search in DiVA

By author/editor
Anderson, Emma K.Kamińska, MagdalenaChartkunchand, Kiattichart C.Eklund, GustavGatchell, MichaelZettergren, HenningCederquist, HenrikSchmidt, Henning T.
By organisation
Department of Physics
In the same journal
Physical Review A: covering atomic, molecular, and optical physics and quantum information
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 53 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf