First LHC transverse beam size measurements with the beam gas vertex detector*

8th International Particle Accelerator Conference

Alexopoulos, A.^1 ; Barchel, C.^1 ; Bay, A.^2 ; Blanc, F.^2 ; Bravin, E.^1 ; Bregliozzi, G.^1 ; Chritin, N.^1 ; Dehning, B.^1 ; Ferro-Luzzi, M.^1 ; Gianì, S.^2 ; Giovannozzi, M.^1 ; Girard, O.^2 ; Greim, R.^3 ; Haefeli, G.^2 ; Hopchev, P.^2 ; Jacobsson, R.^1 ; Jensen, L.^1 ; Rhodri Jones, O.^1 ; Kain, V.^1 ; Karpinski, W.^3 ; Kirn, T.^3 ; Kuonen, A.^2 ; Matev, R.^1 ; Nakada, T.^2 ; Rihl, M.^1 ; Salustino Guimaraes, V.^1 ; Schael, S.^3 ; Schneider, O.^2 ; Schultz Von Dratzig, A.^3 ; Schwering, G.^3 ; Tobin, M.^2 ; Veness, R.^1 ; Veyrat, Q.^2 ; Vlachos, S.^1 ; Wlochal, M.^3 ; Wiirkner, B.^1 ; Xu, Z.^2

CERN, Geneva, Switzerland^1

EPFL, Lausanne, Switzerland^2

I. Physikalisches Institut, Aachen, Germany^3

关键词: Beam profile measurements;    Data acquisition system;    Fast reconstruction;    Operating parameters;    Reconstruction algorithms;    Scintillating fibres;    Transverse beams;    Vertex detectors;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/874/1/012086/pdf
DOI  :  10.1088/1742-6596/874/1/012086

来源: IOP

【 摘 要 】

The Beam Gas Vertex detector (BGV) is an innovative beam profile monitor based on the reconstruction of beam-gas interaction vertices which is being developed as part of the High Luminosity LHC project. Tracks are identified using several planes of scintillating fibres, located outside the beam vacuum chamber and perpendicular to the beam axis. The gas pressure in the interaction volume is adjusted such as to provide an adequate trigger rate, without disturbing the beam. A BGV demonstrator monitoring one of the two LHC beams was fully installed and commissioned in 2016. First data and beam size measurements show that the complete detector and data acquisition system is operating as expected. The BGV operating parameters are now being optimised and the reconstruction algorithms developed to produce accurate and fast reconstruction on a CPU farm in order to provide real time beam profile measurements to the LHC operators.