Scalar quark searches in e(+)e(-) collisions at root s = 181-184 GeV

Searches for scalar top, scalar bottom and degenerate scalar quarks have been performed with data collected with the ALEPH detector at LEP. The data sample consists of 57 pb(-1) taken at root s = 181-184 GeV. No evidence for scalar top, scalar bottom or degenerate scalar quarks was found in the channels (t) over tilde --> c chi, (t) over tilde --> bl (v) over tilde, (b) over tilde --> b chi, and (q) over tilde chi. From the channel (t) over tilde --> c chi a limit of 74 GeV/c(2) has been set on the scalar top quark mass, independent of the mixing angle. This limit assumes a mass difference between the (t) over tilde and the chi in the range 10-40 GeV/c(2). From the channel (t) over tilde --> bl<(nu)over tilde> the mixing-angle-independent scalar top limit is 82 GeV/c(2), assuming m((t) over tilde) - m(<(nu)over tilde>) 10 GeV/c(2). From the channel (b) over tilde --> b chi, a limit of 79 GeV/c(2) has been set on the mass of the supersymmetric partner of the left-handed state of the bottom quark. This limit is valid for m((b) over tilde) - m(x) > 10 GeV/c(2). From the channel (q) over tilde --> q chi, a limit of 87 GeV/c(2) has been set on the mass of supersymmetric partners of light quarks assuming five degenerate flavours and the production of both "left-handed" and "right-handed" squarks. This limit is valid for in m((q) over tilde) - m(x) > 5 CeV/c(2). (C) 1998 Published by Elsevier Science B.V. All rights reserved.