You may check if you need a UK visa using: GOV.UK website.
If requested IAER may issue you a visa supporting letter provided that your paper has been accepted and you have already paid and registered for the conference.
If you require a UK visa, we highly encourage you to submit your paper as soon as possible. Our notification of acceptence is a continuous process. The earlier you submit, the earlier you may receive the feedback and complete your registration and other travel needs.