Absorption cross-section measurements on the vacuum ultra-violet spectrum of zinc vapour

Marr, G. V.; Austin, Joanna

doi:10.1088/0022-3700/2/1/315

Cited by 55 publications

(32 citation statements)

References 15 publications

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“…There are two measurements of the Zn photoabsorption cross section between 110 nm and the photoionisation threshold at 132 nm (Marr & Austin 1969;Yih et al 1998) that disagree by a factor of two. We used an average of these two measurements where they coincide, the measurement of Marr & Austin (1969) between 91 and 110 nm and the relative-photoionisation cross section of Harrison et al (1969) at shorter wavelengths, after scaling its integrated magnitude to match the continuum level of an R-matrix calculation (Huebner & Mukherjee 2015).…”

Section: Zn -Zincmentioning

confidence: 99%

“…We used an average of these two measurements where they coincide, the measurement of Marr & Austin (1969) between 91 and 110 nm and the relative-photoionisation cross section of Harrison et al (1969) at shorter wavelengths, after scaling its integrated magnitude to match the continuum level of an R-matrix calculation (Huebner & Mukherjee 2015).…”

Section: Zn -Zincmentioning

confidence: 99%

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Photodissociation and photoionisation of atoms and molecules of astrophysical interest

Heays

Bosman

Dishoeck

2017

A&A

422

442

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A new collection of photodissociation and photoionisation cross sections for 102 atoms and molecules of astrochemical interest has been assembled, along with a brief review of the basic physical processes involved. These have been used to calculate dissociation and ionisation rates, with uncertainties, in a standard ultraviolet interstellar radiation field (ISRF) and for other wavelength-dependent radiation fields, including cool stellar and solar radiation, Lyman-α dominated radiation, and a cosmic-ray induced ultraviolet flux. The new ISRF rates generally agree within 30% with our previous compilations, with a few notable exceptions. Comparison with other databases such as PHIDRATES is made. The reduction of rates in shielded regions was calculated as a function of dust, molecular and atomic hydrogen, atomic C, and self-shielding column densities. The relative importance of these shielding types depends on the atom or molecule in question and the assumed dust optical properties. All of the new data are publicly available from the Leiden photodissociation and ionisation database. Sensitivity of the calculated rates to variation of temperature and isotope, and uncertainties in measured or calculated cross sections, are tested and discussed. Tests were conducted on the new rates with an interstellar-cloud chemical model, and find general agreement (within a factor of two) in abundances obtained with the previous iteration of the Leiden database assuming an ISRF, and order-of-magnitude variations assuming various kinds of stellar radiation. The newly parameterised dust-shielding factors makes a factor-of-two difference to many atomic and molecular abundances relative to parameters currently in the UDfA and KIDA astrochemical reaction databases. The newly-calculated cosmic-ray induced photodissociation and ionisation rates differ from current standard values up to a factor of 5. Under high temperature and cosmic-ray-flux conditions the new rates alter the equilibrium abundances of abundant dark cloud abundances by up to a factor of two. The partial cross sections for H 2 O and NH 3 photodissociation forming OH, O, NH 2 and NH are also evaluated and lead to radiation-field-dependent branching ratios.

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Section: Zn -Zincmentioning

confidence: 99%

Section: Zn -Zincmentioning

confidence: 99%

Photodissociation and photoionisation of atoms and molecules of astrophysical interest

Heays

Bosman

Dishoeck

2017

A&A

422

442

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“…Figure 2 shows the photoionization cross-section for the ground state of Zn I in a solid line. To compare with the experimental results, we show the experimental data from Marr & Austin (1969) and Harrison et al (1969) as a dashed line and filled circles, respectively. The cross-section near the threshold is shown on an expanded scale at the top left corner, and is shifted by 0.02432 Ry, which is the difference between the calculated ionization potential of the ground state and the experimental value shown in Bartschat (1987).…”

Section: Photoionization Cross-sectionsmentioning

confidence: 99%

“…The cross-section near the threshold is shown on an expanded scale at the top left corner, and is shifted by 0.02432 Ry, which is the difference between the calculated ionization potential of the ground state and the experimental value shown in Bartschat (1987). The dashed line and the filled circles represent the experimental data from Marr & Austin (1969) and Harrison (1969), respectively. The inset at the top left corner is the cross-section near threshold shown on an expanded scale.…”

Section: Photoionization Cross-sectionsmentioning

confidence: 99%

“…Most investigations of the photoionization of Zn I have focused on the ground state 3d 10 4s 2 1 S. Marr & Austin (1969) and Harrison et al (1969) measured the photoionization crosssection of Zn I in the photon energy range of 0.69-1.22 and 0.73-3.69 Ry, respectively. The d-shell absorption spectrum was presented and analyzed by Sommer et al (1987) using synchrotron radiation as the background source.…”

Section: Introductionmentioning

confidence: 99%

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Atomic data of Zn I for the investigation of element abundances

Liu

Cheng

Zeng

et al. 2011

A&A

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Aims. We calculate the energy levels, oscillator strengths, and photoionization cross-sections of Zn I to provide atomic data for the study of element abundances in astrophysics. Methods. The calculations are carried out by using the R-matrix method in the LS-coupling scheme. The lowest 12 terms of Zn II are utilized as target states and extensive configuration interaction is included to properly delineate the quantum states of Zn II and Zn I. Results. The 3443 oscillator-strength values are calculated in both length and velocity forms, for the dipole-allowed transitions between 235 bound states of Zn I. The photoionization cross-section of each bound state is presented in a photon energy range from the first threshold to about 1.5 Ry. Some resonance structures are identified in the photoionization cross-sections. Conclusions. A set of atomic data to derive the spectral characteristics of neutral zinc is obtained. Comparisons are made with available experimental and other theoretical results.

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Comparison of Resonance Harmonics: Experiment and Theory

2018

Resonance Enhancement in Laser‐Produced Plasmas

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Absorption cross-section measurements on the vacuum ultra-violet spectrum of zinc vapour

Cited by 55 publications

References 15 publications

Photodissociation and photoionisation of atoms and molecules of astrophysical interest

Photodissociation and photoionisation of atoms and molecules of astrophysical interest

Atomic data of Zn I for the investigation of element abundances

Comparison of Resonance Harmonics: Experiment and Theory

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