Population ratios for the fine-structure ground state of O I applicable to the interstellar medium

1988 ◽  
Vol 333 ◽  
pp. 806 ◽  
Author(s):  
F. P. Keenan ◽  
K. A. Berrington
Keyword(s):  
Fine Structure ◽  
Interstellar Medium ◽  
Ground State

scholarly journals Population ratios for the fine structure ground state of Si II applicable to the interstellar medium

1985 ◽  
Vol 214 (1) ◽  
pp. 37P-40P ◽  
Author(s):  
F. P. Keenan ◽  
C. T. Johnson ◽  
A. E. Kingston ◽  
P. L. Dufton
Keyword(s):  
Fine Structure ◽  
Interstellar Medium ◽  
Ground State

scholarly journals The prospects for observing [O iii] 52 micron emission from galaxies during the Epoch of Reionization

2021 ◽  
Vol 504 (1) ◽  
pp. 723-730
Author(s):  
Shengqi Yang ◽  
Adam Lidz ◽  
Gergö Popping
Keyword(s):  
Fine Structure ◽  
Interstellar Medium ◽  
Emission Line ◽  
Parameter Space ◽  
Gas Density ◽  
Star Forming ◽  
Upper Limits ◽  
Redshift Galaxies

ABSTRACT The [O iii] 88 $\mu$m fine-structure emission line has been detected into the Epoch of Reionization (EoR) from star-forming galaxies at redshifts 6 < z ≲ 9 with ALMA. These measurements provide valuable information regarding the properties of the interstellar medium (ISM) in the highest redshift galaxies discovered thus far. The [O iii] 88 $\mu$m line observations leave, however, a degeneracy between the gas density and metallicity in these systems. Here, we quantify the prospects for breaking this degeneracy using future ALMA observations of the [O iii] 52 $\mu$m line. Among the current set of 10 [O iii] 88 $\mu$m emitters at 6 < z ≲ 9, we forecast 52 $\mu$m detections (at 6σ) in SXDF-NB1006-2, B14-6566, J0217-0208, and J1211-0118 within on-source observing times of 2–10 h, provided their gas densities are larger than about nH ≳ 102–103 cm−3. Other targets generally require much longer integration times for a 6σ detection. Either successful detections of the 52 $\mu$m line or reliable upper limits will lead to significantly tighter constraints on ISM parameters. The forecasted improvements are as large as ∼3 dex in gas density and ∼1 dex in metallicity for some regions of parameter space. We suggest SXDF-NB1006-2 as a promising first target for 52 $\mu$m line measurements. We discuss how such measurements will help in understanding the mass–metallicity relationship during the EoR.

An Investigation on the Fine Structure Levels in the Ground State Configuration for the Antimony Anion

2014 ◽  
Vol 69 (8-9) ◽  
pp. 397-402
Author(s):  
Leyla Özdemir ◽  
Sadiye Tuna
Keyword(s):  
Fine Structure ◽  
Ground State ◽  
Transition Probabilities ◽  
Relativistic Effects ◽  
Electric Quadrupole ◽  
Radiative Transition ◽  
Ground State Configuration ◽  
Hartree Fock ◽  
First Time ◽  
State Configuration

We have investigated the correlation, relativistic, and isotope shift effects on the fine structure levels in the ground state configuration for the antimony anion ( Sb-). Energies and radiative transition probabilities (for magnetic dipole, M1, and electric quadrupole, E2) have been obtained using the multiconfiguration Hartree-Fock method within the framework of the Breit-Pauli Hamiltonian. Therefore, the most important configuration interaction and relativistic effects have been included. Comparisons with other available works are presented. For some M1 and E2 lines the considered transition probabilities are reported for the first time

scholarly journals First Results from the Submillimeter Wave Astronomy Satellite – H2O and O2 Discoveries

2000 ◽  
Vol 197 ◽  
pp. 161-174
Author(s):  
Gary J. Melnick
Keyword(s):  
Interstellar Medium ◽  
Ground State ◽  
Molecular Clouds ◽  
Submillimeter Wave ◽  
Important Species ◽  
First Results ◽  
One Year

The Submillimeter Wave Astronomy Satellite (SWAS) was successfully launched on 5 December 1998 with the goals of studying: (1) the distribution of oxygen in the interstellar medium; (2) the role of H2O and O2 as gas coolants; and (3) the UV-illuminated surfaces of molecular clouds. To achieve these goals, SWAS is conducting pointed observations of dense (n(H2) > 103 cm–3) molecular clouds throughout our Galaxy in either the ground-state or a low-lying transition of five astrophysically important species: H2O, H218O, O2, CI, and 13CO. SWAS has made great strides in each of these areas of investigation. This paper will summarize our H2O and O2 findings one year into the mission.

scholarly journals Methyl Internal Rotation Fine Structure in the Ground State Rotational Spectrum of Gauche Butane

1990 ◽  
Vol 45 (8) ◽  
pp. 989-994 ◽  
Author(s):  
Kirsten Vormann ◽  
Helmut Dreizler ◽  
Hans Hübner ◽  
Wolfgang Hüttner
Keyword(s):  
Fine Structure ◽  
Internal Rotation ◽  
Barrier Height ◽  
Ground State ◽  
High Accuracy ◽  
Rotational Spectrum ◽  
Frequency Range ◽  
Vibrational Ground State ◽  
Rotation Parameters

Abstract The methyl torsional fine structure in the rotational spectrum of gauche butane in the vibrational ground state was investigated in the frequency range between 10 and 141 GHz. Using the internal axis method (IAM) in the formulation of Woods, all internal rotation parameters were determined with high accuracy. The barrier height of the methyl internal rotation was determined to 11.34 (29) kJ/mol (2.710 (69) kcal/mol)

Sign in / Sign up

Export Citation Format

Share Document