Author/Authors :
Aleksandrov، نويسنده , , D. and Alme، نويسنده , , J. and Basmanov، نويسنده , , V. and Batyunya، نويسنده , , Janos B. and Blau، نويسنده , , D. and Bogolyubsky، نويسنده , , M. and Budilov، نويسنده , , V. N. Budnikov and E. Z. Gusakov ، نويسنده , , D. and Buskenes، نويسنده , , J.I. and Cai، نويسنده , , X. and Chuman، نويسنده , , F. and Deloff، نويسنده , , A. and Demanov، نويسنده , , V. and Djuvsland، نويسنده , , O. and Dobrowolski، نويسنده , , T. and Faltys، نويسنده ,
Abstract :
We solve numerically a deconvolution problem to extract the undisturbed spectrum from the measured distribution contaminated by the finite resolution of the measuring device. A problem of this kind emerges when one wants to infer the momentum distribution of the neutral pions by detecting the π 0 decay photons using the photon spectrometer of the ALICE LHC experiment at CERN [1]. The underlying integral equation connecting the sought for pion spectrum and the measured gamma spectrum has been discretized and subsequently reduced to a system of linear algebraic equations. The latter system, however, is known to be ill-posed and must be regularized to obtain a stable solution. This task has been accomplished here by means of the Tikhonov regularization scheme combined with the L-curve method. The resulting pion spectrum is in an excellent quantitative agreement with the pion spectrum obtained from a Monte Carlo simulation.
Keywords :
Deconvolution , Photon spectrometer , ALICE experiment , Ill-posed problem , Tikhonov Regularization , L-curve method
