Presentation on theme: "Avant modification. Modification BBLR LSS2 20 27 Les distances sont prises entre laxe du faisceau et la tangente externe du fil. La marge de securite."— Presentation transcript:
Modification BBLR LSS2 20 27 Les distances sont prises entre laxe du faisceau et la tangente externe du fil. La marge de securite est augmentee: - 1mm pour le fil vertical, soit d=20mm au lieu de 19mm - 0.5 mm pour le fil a 45 degre, soit d=27mm au lieu de 26.5mm La distance a laxe du fil horizontal est inchangee. La position du fil horizontal reste a preciser (inner/outer?): latest from Jorg: OUTER Outer side ? ok
Original with a more complete cotation (LSS5) 22 Intermediate position: the H and 45deg wires are in nominal position; the V wire leaves a clearance of 22 mm. An issue arises when the set-up is lowered to the 12 sigma position: 19 *12/9.5= 24 mm. The 45 deg wire is then lowered by 2mm and becomes the aperture limit. This is only encountered in BBLR MDs, i.e. there is no danger of damage due to the low intensity. Still, the 45 deg wire may divert the losses from the nominal aperture limit. The modification involves raising the 45 deg by 2mm vertical. 53 or more 2 In point 5, the horizontal aperture is too tight for a FT beam with low momentum spread; we need to retract the horizontal wire by 2 mm.
Modification to BBLR in LSS2 V wireH wire45d wire 0, -2051, 0 no change! 19.10, 19.10 The position of the H wire (OUTER side) is governed by the sign of the extraction bump which is negative here (i.e., at the inside of the ring); the H wire should be opposite to the bump.
Modification to BBLR in LSS5 PositionV wireH wire45d wire intermediate0,-22 -53, 0-18.75,20.75 perfect correction (IN)0,-19-53, 3-18.75,23.75 12 correction (OUT)0,-24-53, -2-18.75,18.75 Outside of MD time, the set-up is in intermediate position. MD with the 45 deg wire requires the OUT position. The position of the H wire (INNER side) is governed by the position of the LSS2 H wire: it must be opposite to get the 45 deg. wires at 45 deg.