1. http://europlanet-ri.eu UCL online tools: An application for computing H3+ cooling rate Dugan Witherick / Steve Miller / Nick Achilleos Miracle Computational Officer / Lecturers, Departments of Physics / Science and Technology Studies University College London JRA3 Workshop @ UCL: 22-24 April 2010

2. http://europlanet-ri.eu  What is H3+ ? A molecular ion which strongly radiates in the infrared wavelength region (3-4 micron) - transitions between ro-vibrational levels. Important element of ‘energy budget’ for ionospheres of hydrogen-rich gas giants esp. Jupiter and Saturn. Especially auroral regions. For example:

3. http://europlanet-ri.eu  Aspects of H3+ emission A molecular ion which strongly radiates in the infrared wavelength region (3-4 micron) - transitions between ro-vibrational levels. Important element of ‘energy budget’ for ionospheres of hydrogen-rich gas giants esp. Jupiter and Saturn. Especially auroral regions. For example, Jupiter’s auroral oval radiates of order 10 11 - 10 12 W in the UV and IR bands. Clarke et al, Nature, 2002

4. http://europlanet-ri.eu  Aspects of H3+ emission Departures from LTE become important in determining H3+ emission from the Jovian thermosphere, at altitudes above 500 km (zero-point=1 B level) (Melin et al, Icarus, 2005) Timescales for radiative de-excitation become competitive with collisional de- excitation. By ~2000 km altitude, typical excited vibrn levels have populations <10% of value predicted by LTE ! Example of calculation from Melin et al 2005

5. 5JRA3 Workshop @ UCL: 22-24/04/2010 ‘H3PCool’ Introduction to application (source code by S. Miller, deployment over web by D. Witherick) - ‘Home page’:

6. ‘H3PCool’ Introductory text and references, courtesy of Dugan

7. ‘H3PCool’ Input fields for H2 density grid and Temperature grid, email address

8. ‘H3PCool’ Information about requested run received upon ‘click’ for submission

10. ‘H3PCool’ Email link takes user to several output files. The most basic shows the columns of density, temperature and emission per H3+ molecule in W/str. Can download as ASCII or choose to have the output files sent in an email. Important for accurate interpretation of infrared auroral emissions, in the context of diagnosing auroral/ionospheric conditions. Important input for radiative transfer models and GCMs.