- ID:
- ivo://CDS.VizieR/J/PAZh/28/41
- Title:
- Eu III oscillator strengths
- Short Name:
- J/PAZh/28/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The calculations of the spectrum and oscillator strengths for the 4f^7^-(4f^6^5d+4f^6^6s) Eu III transitions. The calculations were performed with Cowan's RCN-RCG-RCE codes in the single-configuration approximation. The new oscillator strengths were tested by analyzing the Europium abundances using Eu II and Eu III lines in the spectra of hot peculiar stars ({alpha}^2^ CVn is a typical representative) and a cool peculiar stars ({beta} CrB is a typical representative).
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/AZh/81/33
- Title:
- Excitation of PtI transitions
- Short Name:
- J/AZh/81/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have experimentally studied the excitation of transitions of the platinum atom ending in levels of the ^3^D main term. The atoms were excited by a 30 eV monoenergetic electron beam. The lines studied are located at wavelengths of 204-367nm. The largest of the measured excitational cross sections exceed 10^-16^cm^2^. The optical-excitation functions measured at electron energies of 0-200eV have complex structures.
- ID:
- ivo://CDS.VizieR/J/ApJS/123/311
- Title:
- Excitation rate coefficients for O III
- Short Name:
- J/ApJS/123/311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Collision strengths for fine-structure transitions among the levels of the (1s^2^) 2s^2^2p^2^, 2s2p^3^, 2p^4^, 2s^2^2p3s, 2s^2^2p3p, and 2s^2^2p3d configurations of O III have been computed over a wide range of energies below 13.0 ryd using the R-matrix program. All partial waves with L{<=}40 have been included to ensure the convergence of results. Excitation rate coefficients, in the form of dimensionless effective collision strengths, have also been computed at temperatures below 200,000 K. The results are compared with available calculations, and accuracy of the data is assessed.
- ID:
- ivo://CDS.VizieR/J/A+A/407/769
- Title:
- Excitation rates for transitions in Ca XV
- Short Name:
- J/A+A/407/769
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Collision strengths for transitions among the energetically lowest 46 fine-structure levels belonging to the (1s^2^) 2s^2^2p^2^, 2s2p^3^, 2p^4^, and 2s^2^2p3l configurations of Ca XV are computed, over a wide electron energy range below 300Ryd, using the Dirac Atomic R-matrix Code (DARC) of Norrington & Grant (2003, Comput. Phys. Comm., in preparation). Resonances in the threshold region have been resolved in a fine energy mesh, and excitation rates are determined over a wide electron temperature range below 10^7^K. The results are compared with those available in the literature, and the accuracy of the data is assessed.
- ID:
- ivo://CDS.VizieR/J/MNRAS/437/1828
- Title:
- ExoMol line list for HCN and HNC
- Short Name:
- J/MNRAS/437/1828
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A revised rotation-vibration line list for the combined hydrogen cynanide (HCN)/hydrogen isocyanide (HNC) system is presented. The line list uses ab initio transition intensities calculated previously (Harris et al., 2002ApJ...578..657H) and extensive datasets of recently measured experimental energy levels. The resulting line list has significantly more accurate wavelengths than previous ones for these systems. An improved value for the separation between HCN and HNC is adopted leading to an approximately 25% lower predicted thermal population of HNC as a function of temperature in the key 2000 to 3000K region. Temperature-dependent partition functions and equilibrium constant are presented. The line lists are validated by comparison with laboratory spectra and are presented in full as supplementary data to the article and at www.exomol.com.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/1363
- Title:
- ExoMol line list for H_2_^18^O and H_2_^17^O
- Short Name:
- J/MNRAS/466/1363
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hot line lists for two isotopologues of water, H_2_^18^O and H_2_^17^O, are presented. The calculations employ newly constructed potential energy surfaces (PES), which take advantage of a novel method for using the large set of experimental energy levels for H_2_^16^O to give high-quality predictions for H_2_^18^O and H_2_^17^O. This procedure greatly extends the energy range for which a PES can be accurately determined, allowing an accurate prediction of higher lying energy levels than are currently known from direct laboratory measurements. This PES is combined with a high-accuracy, ab initio dipole moment surface of water in the computation of all energy levels, transition frequencies and associated Einstein A coefficients for states with rotational excitation up to J=50 and energies up to 30000cm^-1^. The resulting HotWat78 line lists complement the well-used BT2 H_2_^16^O line list.
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/4063
- Title:
- ExoMol line list for H2S AYT2
- Short Name:
- J/MNRAS/460/4063
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This work presents the AYT2 line list: a comprehensive list of 115 million ^1^H_2_^32^S vibration-rotation transitions computed using an empirically adjusted potential energy surface and an ab initio dipole moment surface. The line list gives complete coverage up to 11000cm^-1^ (wavelengths longer than 0.91um) for temperatures up to 2000K. Room temperature spectra can be simulated up to 20000cm^-1^ (0.5um) but the predictions at visible wavelengths are less reliable. AYT2 is made available in electronic form as supplementary data to this paper at www.exomol.com.
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/1821
- Title:
- ExoMol line list for KCl
- Short Name:
- J/MNRAS/442/1821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate rotation-vibration line lists for two molecules, NaCl and KCl, in their ground electronic states are presented. These line lists are suitable for temperatures relevant to exoplanetary atmospheres and cool stars (up to 3000K). Isotopologues ^23^Na^35^Cl, ^23^Na^37^Cl, ^39^K^35^Cl, ^39^K^37^Cl, ^41^K^35^Cl and ^41^K^37^Cl are considered. Laboratory data were used to refine ab initio potential energy curves in order to compute accurate ro-vibrational energy levels. Einstein A coefficients are generated using newly determined ab initio dipole moment curves calculated using the CCSD(T) method. New Dunham Yij constants for KCl are generated by a re-analysis of a published Fourier transform infrared emission spectra. Partition functions plus full line lists of ro-vibration transitions are made available in an electronic form here and at www.exomol.com.
- ID:
- ivo://CDS.VizieR/J/MNRAS/445/1383
- Title:
- ExoMol line list for phosphorus nitride (PN)
- Short Name:
- J/MNRAS/445/1383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate rotational-vibrational line lists for two isotopologues of PN in their ground electronic states are computed. The line lists are produced using an empirical potential energy curve obtained by fitting to the experimental transition frequencies available in the literature in conjunction with an accurate, high level ab initio dipole moment curve. In these calculations the programs DPotFit and LEVEL 8.0 were used. The new line lists reproduce the experimental wavenumbers with a root-mean-square error of 0.004cm^-1^. The line lists cover the frequency range 0-51000cm^-1^, contain almost 700000 lines each and extend up to a maximum vibrational level of v=66 and a maximum rotational level of J=357. They should be applicable for a large range of temperature up to, at least, 5000K. These new line lists are used to simulate spectra for PN at a range of temperatures and are deposited in the Strasbourg data centre. This work is part of the ExoMol project (2012MNRAS.425...21T).
- ID:
- ivo://CDS.VizieR/J/MNRAS/479/1401
- Title:
- ExoMol line lists. AlH
- Short Name:
- J/MNRAS/479/1401
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new line list for AlH is produced. The WYLLoT line list spans two electronic states X^1^{SIGMA}^1^ and A^1^{PI}. A diabatic model is used to model the shallow potential energy curve of the A^1^{PI} state, which has a strong pre-dissociative character with only two bound vibrational states. Both potential energy curves are empirical and were obtained by fitting to experimentally derived energies of the X^1^{SIGMA}^1^ and A^1^{PI} electronic states using the diatomic nuclear motion codes Level and Duo. High temperature line lists plus partition functions and lifetimes for three isotopologues ^27^AlH, ^27^AlD and ^26^AlH were generated using ab initio dipole moments obtained with the MRCI/aug-cc-pV5Z level of theory. The line lists cover both the X-X and A-X systems and are made available in electronic form at the CDS and ExoMol databases.
