Domicile is a concept of common law that is used in tax law for certain purposes. HM Revenue and Customs applies this legal concept to the facts of each case, those facts being established through the normal inquiry process.
HMRC has produced detailed guidance on domicile which gives an indication of the kind of information and documents that HMRC might request during an inquiry. These lists are not exhaustive. The guidance is available at:
http://www.hmrc.gov.uk/cnr/domicile-tier2.pdf
This information is not available, as individuals are not required to report their UK domicile status or residence status to HM Revenue and Customs unless either is relevant to their liability to UK tax within that year.