title: Multiwire proportional chamber system of the Fermilab single arm spectrometer.
abstract: We describe a system of two groups of multiwire proportional chambers and its special purpose interface used in the Single Arm Spectrometer (SAS) facility at Fermilab. The first set measures the coordinates of the fast particle going into the spectrometer arm with a space resolution down to +/-0.5 mm. The second set, close to the target, measures the multiplicity and angular distributions of charged particles coming from the interaction. The chambers of this set have three sensitive planes with wires at 120 degrees in the same gas volume to measure three coordinates for each physical point, two readout channels per wire to minimize the inefficiency due to the very high flux and insensitive regions at the center of the chambers where they are crossed by the beam.
authors.affiliation: Istituto di Fisica e Sezione INFN, 70126 Bari, Italy.
authors.forename: E F
authors.initials: EF
authors.lastname: Anelli
authors.forename: M T
authors.initials: MT
authors.lastname: Chiaradia
authors.forename: C
authors.initials: C
authors.lastname: De Marzo
authors.forename: A
authors.initials: A
authors.lastname: Distante
authors.forename: C
authors.initials: C
authors.lastname: Favuzzi
authors.forename: R
authors.initials: R
authors.lastname: Ferorelli
authors.forename: G
authors.initials: G
authors.lastname: Germinario
authors.forename: L
authors.initials: L
authors.lastname: Guerriero
authors.forename: P
authors.initials: P
authors.lastname: La Vopa
authors.forename: G
authors.initials: G
authors.lastname: Maggi
authors.forename: M
authors.initials: M
authors.lastname: Perchiazzi
authors.forename: F
authors.initials: F
authors.lastname: Posa
authors.forename: A
authors.initials: A
authors.lastname: Sacchetti
authors.forename: G
authors.initials: G
authors.lastname: Selvaggi
authors.forename: P
authors.initials: P
authors.lastname: Spinelli
authors.forename: F
authors.initials: F
authors.lastname: Waldner