Ron Allen, Exploring ISM Physics and Galactic Structure with 18cm OH Emissi
December 12, 2019 Ron Allen, Exploring ISM Physics and Galactic Structure with 18cm OH Emissi Exploring ISM Physics and Galactic Structure with 18cm OH Emission at the GBO] This talk will summarize recent radio observations and theoretical modeling work on the 18-cm lines of the OH molecule in the low-density Galactic ISM. Over the past several years, together with my colleagues and students, I have been exploring using this tracer as an alternative to the millimeter lines of the CO molecule for studies of the ISM in the Outer Galaxy. The OH lines appear especially useful as tracers of the diffuse H2 which we think pervades most of the volume of the ISM in the Galaxy, and in which the level of collisional excitation may be insufficient to excite CO emission. The OH lines show promise both for studies of diffuse ISM physics, and for mapping the large-scale spatial distribution and kinematics of H2 in the Outer Galaxy. As an example of the latter I will present some preliminary results on a remarkable disk-like feature in molecular gas which we have serendipitously discovered in the Outer Galaxy.
December 12, 2019 Ron Allen, Exploring ISM Physics and Galactic Structure with 18cm OH Emissi Exploring ISM Physics and Galactic Structure with 18cm OH Emission at the GBO] This talk will summarize recent radio observations and theoretical modeling work on the 18-cm lines of the OH molecule in the low-density Galactic ISM. Over the past several years, together with my colleagues and students, I have been exploring using this tracer as an alternative to the millimeter lines of the CO molecule for studies of the ISM in the Outer Galaxy. The OH lines appear especially useful as tracers of the diffuse H2 which we think pervades most of the volume of the ISM in the Galaxy, and in which the level of collisional excitation may be insufficient to excite CO emission. The OH lines show promise both for studies of diffuse ISM physics, and for mapping the large-scale spatial distribution and kinematics of H2 in the Outer Galaxy. As an example of the latter I will present some preliminary results on a remarkable disk-like feature in molecular gas which we have serendipitously discovered in the Outer Galaxy.