NUMERICAL STUDY OF THE NAMBU-GOTO STRING MODEL AT FINITE-LENGTH AND TEMPERATURE

We study the Nambu-Goto model numerically for a string of finite lengt h at an arbitrary temperature. The static quark-antiquark potential is investigated and it is found that the deconfinement radius r(dec) (th e distance between quarks for which the potential vanishes) is indepen dent of the temperature. For tau = tau(dec) (the temperature for which the string tension vanishes), the potential becomes a constant for la rge r, thus losing its ''confining'' property. This is clearly a consi stent result with the interpretation of tau(dec) as a deconfinement te mperature. For tau > tau(dec), solutions to the gap equations exist wh ich allow us to have a well-defined quark potential although only for ''unconfining'' strings of a certain length. The string tension at fin ite temperature for a string of various lengths is also calculated as well as tau(dec)max (the maximum temperature for which a tension exist s) which might signal a first-order transition to a deconfined phase.