  Hydrogen-burning is the root cause of the star-to-star abundance variations
of light nuclei in Galactic globular clusters (GC). In the present work we
constrain the physical conditions that gave rise to the observed abundance
patterns of Li, C, N, O, Na, Mg, Al, as well as Mg isotopes in the typical case
of NGC6752. We perform nucleosynthesis calculations at constant temperature,
adopting realistic initial abundances for the proto-cluster gas. We use a
detailed nuclear reaction network and state-of-the-art nuclear reaction rates.
Although simplistic, our analysis provides original results and new constraints
on the self-enrichment scenario for GCs. Our parametrized calculations allow us
to determine a narrow range of temperature where the observed extreme
abundances of all light elements and isotopes in NGC6752 are nicely reproduced
simultaneously. This agreement is obtained after mixing of the H-processed
material with 30 % of unprocessed gas. The observed C-N, O-Na, Mg-Al, Li-Na and
F-Na anticorrelations, as well as the behaviour of the Mg isotopes can be
recovered by assuming mixing with even larger dilution factors. Li production
by the stars that build up the other abundance anomalies is not mandatory in
the case of NGC 6752. Observations of O, Na, Mg and Al constrain the
temperature range for H-burning; such temperatures are encountered in the two
main candidate ``polluters'' proposed for GCs, namely massive AGBs and the most
massive main-sequence stars. (Abridged).
