- ID:
- ivo://CDS.VizieR/VI/72
- Title:
- Atomic Transition Probabilities, Sc-Ni
- Short Name:
- VI/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Atomic transition probabilities for Scandium (Z = 21) through Ni (Z = 28) for about 18,300 spectral lines are critically compiled, based on all available literature sources. The transition probability data, oscillator strengths, and line shape data were collected, catalogued and evaluated by the Data Center on Atomic Transition Probabilities at the National Institute of Standards and Technology, USA (NIST).
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- ID:
- ivo://CDS.VizieR/J/A+A/444/305
- Title:
- A-values + oscillator strength of Ca XIII
- Short Name:
- J/A+A/444/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Electron impact collision strengths, energy levels, oscillator strengths and spontaneous radiative decay rates are calculated for Ca XIII. The configurations used are 2s2.2p4, 2s.2p5, 2p6, 2s2.2p3.3s, 2s2.2p3.3p and 2s2.2p3.3d giving rise to 86 fine-structure levels in intermediate coupling. Collision strengths are calculated at five incident energies (40, 80, 120, 160 and 200Ry) in the distorted wave approximation. Excitation rate coefficients are calculated as a function of electron temperature by assuming a Maxwellian electron velocity distribution. Using the excitation rate coefficients and the radiative transition rates, statistical equilibrium equations for level populations are solved at electron densities covering the range of 10^8-10^14cm^-3 at an electron temperature of logTe(K)=6.5, corresponding to maximum abundance of Ca XIII. Relative and absolute spectral line intensities are calculated, and their diagnostic relevance is discussed. This dataset will be made available in the next version of the CHIANTI database.
- ID:
- ivo://CDS.VizieR/J/A+A/434/365
- Title:
- A-values & oscillator strength of O-like ions
- Short Name:
- J/A+A/434/365
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the present work a complete set of radiative transition rates is calculated for all for the O-like ions with Z=11-30. Energy levels, oscillator strengths and A values are computed for all transitions within the n=2 complex and are compared with previous calculations, where available. Calculations are carried out using the Superstructure code. The present work provides for the first time a self-consistent, complete set of A values necessary for the calculation of line emissivities and synthetic spectra for all the ions considered, filling several gaps in the existing literature. The present data are especially suited for the analysis of spectral lines emitted by the less-abundant elements in the universe, for which few if any data were available in the literature.
- ID:
- ivo://CDS.VizieR/VI/133
- Title:
- A variationally computed hot NH3 line list - BYTe
- Short Name:
- VI/133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 'BYTe' a comprehensive 'hot' line list of ro-vibrational transitions of ammonia, ^14^NH_3_, in its ground electronic state. It comprises 1,138,323,351 transitions with frequencies up to 12,000cm^-1^, constructed from 1,373,897 energy levels below 18,000cm^-1^ having J values less than 37. The line list is sufficiently accurate and complete for high resolution spectroscopy and atmospheric modelling of astrophysical objects, including brown dwarfs and exoplanets at temperatures up to 1,500K. The data are in two parts. The first, nh3_0-41.dat contains a list of 4,167,360 rovibrational states, ordered by J (max= 41), symmetry block and energy (in cm^-1^). Only one third of the states (1,373,897) are within the parameters used for generating transitions (see above), but all the states are required for computing temperature-dependent partition functions. Each state is labelled with: seven normal mode vibrational quantum numbers; three rotational quantum numbers and the total symmetry quantum number, Gamma. In addition there are six local mode vibrational numbers and a local mode vibrational symmetry quantum numbers, which we include because the basis set used in our calculations is expressed in terms of these local mode quantum numbers. Each rovibrational state has a unique number, which is the number of the row in which it appears in the file. This number is the means by which the state is related to the second part of the data system, the transitions files. Because of their size, the transitions are listed in 120 separate files, each containing all the transitions in a 100cm^-1^ frequency range. These and their contents are ordered by increasing frequency. The name of the file includes the lowest frequency in the range; thus the a-00500.dat file contains all the transitions in the frequency range 500-600cm^-1^. The transition files contain three columns: the reference number in the energy file of the upper state; that of the lower state; and the Einstein A coefficient of the transition. The energy file and the transitions files are zipped, and need to be extracted before use. There is a Fortran 90 programme, sp_byte.f90 which may be used to generate synthetic spectra (see sp_byte.txt for details). Using this, it is possible to generate absorption or emission spectra in either 'stick' form or else convoluted with a gaussian with the half-width at half maximum being specified by the user, or with a the temperature-dependent doppler half-width. Three sample input files for use with sp_byte.f90 are supplied: "stick300.in", "gauss300.in", and "sp08900.in" (generates a spectrum for 8900-9000cm^-1^).
- ID:
- ivo://CDS.VizieR/J/A+AS/122/163
- Title:
- Ba I & Ba II Stark broadening
- Short Name:
- J/A+AS/122/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a semiclassical approach, we have calculated electron-, proton-, and ionized helium-impact line widths and shifts for 14 Ba I and 64 Ba II multiplets for perturber densities 10^15^-10^18^cm^-3^ and temperatures T=2500-50000K for BaI and 5000-100000K for Ba II. The results have been compared with available experimental and theoretical data.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A10
- Title:
- Ba V, Ba VI, and Ba VII oscillator strengths
- Short Name:
- J/A+A/566/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the spectral analysis of high-resolution and high-signal-to-noise (S/N) spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Reliable Ba V-VII oscillator strengths are used to identify Ba lines in the spectra of the DA-type white dwarf G191-B2B and the DO-type white dwarf RE 0503-289 and to determine their photospheric Ba abundances. We newly calculated Ba V-VII oscillator strengths to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for the analysis of Ba lines exhibited in high-resolution and high-S/N UV observations of G191-B2B and RE 0503-289.
- ID:
- ivo://CDS.VizieR/J/ApJ/763/L33
- Title:
- Be-B concentrations in rare CB/CH chondrite
- Short Name:
- J/ApJ/763/L33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search for short-lived ^10^Be in 21 calcium-aluminum-rich inclusions (CAIs) from Isheyevo, a rare CB/CH chondrite, showed that only 5 CAIs had ^10^B/^11^B ratios higher than chondritic correlating with the elemental ratio ^9^Be/^11^B, suggestive of in situ decay of this key short-lived radionuclide. The initial (^10^Be/^9^Be)_0_ ratios vary between ~10^-3^ and ~10^-2^ for CAI 411. The initial ratio of CAI 411 is one order of magnitude higher than the highest ratio found in CV3 CAIs, suggesting that the more likely origin of CAI 411 ^10^Be is early solar system irradiation. The low (^26^Al/^27^Al)_0_ [<=8.9x10^-7^] with which CAI 411 formed indicates that it was exposed to gradual flares with a proton fluence of a few 10^19^protons/cm2, during the earliest phases of the solar system, possibly the infrared class 0. The irradiation conditions for other CAIs are less well constrained, with calculated fluences ranging between a few 10^19^ and 10^20^protons/cm2. The variable and extreme value of the initial ^10^Be/^9^Be ratios in carbonaceous chondrite CAIs is the reflection of the variable and extreme magnetic activity in young stars observed in the X-ray domain.
- ID:
- ivo://CDS.VizieR/J/ApJ/829/14
- Title:
- Behavior of heavy elements in H-He-Z mixtures
- Short Name:
- J/ApJ/829/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The core-accretion model for giant planet formation suggests a two-layer picture for the initial structure of Jovian planets, with heavy elements in a dense core and a thick H-He envelope. Late planetesimal accretion and core erosion could potentially enrich the H-He envelope in heavy elements, which is supported by the threefold solar metallicity that was measured in Jupiter's atmosphere by the Galileo entry probe. In order to reproduce the observed gravitational moments of Jupiter and Saturn, models for their interiors include heavy elements, Z, in various proportions. However, their effect on the equation of state of the hydrogen-helium mixtures has not been investigated beyond the ideal mixing approximation. In this article, we report results from ab initio simulations of fully interacting H-He-Z mixtures in order to characterize their equation of state and to analyze possible consequences for the interior structure and evolution of giant planets. Considering C, N, O, Si, Fe, MgO, and SiO_2_, we show that the behavior of heavy elements in H-He mixtures may still be represented by an ideal mixture if the effective volumes and internal energies are chosen appropriately. In the case of oxygen, we also compute the effect on the entropy. We find the resulting changes in the temperature-pressure profile to be small. A homogeneous distribution of 2% oxygen by mass changes the temperature in Jupiter's interior by only 80K.
- ID:
- ivo://CDS.VizieR/J/ApJS/234/40
- Title:
- Be-like ions from BII to NeVII transition data
- Short Name:
- J/ApJS/234/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large-scale self-consistent multiconfiguration Dirac-Hartree-Fock (MCDHF) and relativistic configuration interaction (RCI) calculations are reported for the n<=6 levels in Be-like ions from BII to NeVII. Effects from electron correlation are taken into account by means of large expansions in terms of a basis of configuration state functions, and a complete and accurate data set of excitation energies; lifetimes; wavelengths; electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole line strengths; transition rates; and oscillator strengths for these levels is provided for each ion. Comparisons are made with available experimental and theoretical results. The uncertainty of excitation energies is assessed to be 0.01% on average, which makes it possible to find and rule out misidentifications and aid new line identifications involving high-lying levels in astrophysical spectra. The complete data set is also useful for modeling and diagnosing astrophysical plasmas.
- ID:
- ivo://CDS.VizieR/J/A+A/547/A87
- Title:
- B-like iso-electronic sequence
- Short Name:
- J/A+A/547/A87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present our calculated data including energy levels, radiative decay rates and effective collision strengths for all the transitions among the 204 fine-structure levels of boron-like iso-electronic sequence, belonging to configurations of 2s^x^ 2p^y^ (x+y=3), 2s2 3l, 2s2 4l, 2s 2p 3l, 2s 2p 4l, 2p2 3l The effective collision strengths at 13 temperatures ranging from 2x10^2^(q+1)^2^ to 2x10^6(q+1)^2^K, where q is the residual charge of ions, i.e. Z-5, have been calculated using the ICFT R-matrix method. The data format adopts ADAS adf04 format, see the file at website http://www.adas.ac.uk/man/appxa-04.pdf Filename format: sequence_author(no_space)year_element(no_space)charge.dat. For example Ne^5+, blike_lgy12_ne5.dat
