A rapidly increasing number of teletherapy treatment modalities, e.g. intensity modulated radiation therapy (IMRT), volumetric arc therapy (VMAT) or stereotactic radiosurgery (SRS), is capable of applying small irradiation fields. Field sizes can be as small as 1 cm x 1 cm or below. The main physical and measurement related effects to consider when performing dose measurements in small fields w...

— We study curves and their Jacobians over F̄p and Q̄, and discuss applications to rational connectivity over these fields. We introduce certain dynamical systems on P, induced by translates by torsion points on elliptic curves, and study fields related to these systems.

Let D > 1 be an integer, and let b = b(D) > 1 be its smallest divisor. We show that there are infinitely many number fields of degree D whose primitive elements all have relatively large height in terms of b, D and the discriminant of the number field. This provides a negative answer to a questions of W. Ruppert from 1998 in the case when D is composite. Conditional on a very weak form of a fol...

Let K/k be a finite extension of a global field. Such an extension can be generated over k by a single element. The aim of this article is to prove the existence of a ”small” generator in the function field case. This answers the function field version of a question of Ruppert on small generators of number fields.

background: prediction of the absorbed dose in irradiated volume plays an important role in the outcome of radiotherapy. application of small fields for radiotherapy of thorax makes the dose calculation process inaccurate due to the existence of electronic disequilibrium and intrinsic deficiencies in dose calculation algorithms. to study the lung absorbed dose in radiotherapy with small fields,...