LGV Analysis of Hydroperoxy Radical (HO2): Spectral Lines for Its Detection in a Cosmic Object

Abstract

Knowing rotational and centrifugal distortion constants in conjunction with electric dipole moment for HO₂ radical, we have calculated energies for rotational levels (without fine-structure splitting), and probabilities for radiative transitions between the levels. The radiative transition probabilities in conjunction with the scaled values for rate coefficients for collisional transitions between the levels, the Large Velocity Gradient (LVG) analysis for HO₂ is performed. Two observed lines, 2₀₂-1₀₁ and 4₀₄-3₀₃ of HO2 are found to show MASER action. Seven lines 1₁₀-1₁₁, 2_{1. 1}-2_{1. 2}, 3_{1. 2}-3_{1. 3}, 4_{1. 3}-4_{1. 4}, 5_{1. 4}-5_{1. 5}, 6_{1. 5}-6_{0. 6} and 7_{1. 6}-7_{0. 7} are found to show anomalous absorption and five more lines, 7_{1. 6}-7_{1. 7}, 1_{1. 0}-1_{0. 1}, 2_{2. 1}-3_{1. 2}, 4_{2. 3}-3_{1. 2} and 4_{4. 1}-3_{3. 0} are found to show MASER action. These 14 lines are analyzed here and they may play key role in the identification of HO₂ in a cosmic object.