TY - JOUR
T1 - Measurement of anti-deuteron photoproduction and a search for heavy stable charged particles at HERA
AU - Aktas, A
AU - Coppens, Yves
AU - Dowell, John
AU - Faulkner, Peter
AU - Fleming, Yves
AU - Garvey, John
AU - Henshaw, Oliver
AU - Johnson, Carrie
AU - Kenyon, Ian
AU - Newman, Paul
AU - Rizvi, Syed
AU - Thompson, Paul
AU - Woehrling, Ethan-Etienne
PY - 2004/8/1
Y1 - 2004/8/1
N2 - The cross section for anti-deuteron photoproduction is measured at HERA at a mean centre-of-mass energy of W-gammap=200 GeV in the range 0.2 <p(T)/M <0.7 and \y\ <0.4, where M, p(T) and y are the mass, transverse momentum and rapidity of the anti-deuteron in the HERA laboratory frame, respectively. The numbers of anti-deuterons per event are found to be similar in photoproduction to those in central proton-proton collisions at the CERN ISR but much lower than those in central Au-Au collisions at RHIC. The coalescence parameter B-2, which characterizes the likelihood of anti-deuteron production, is measured in photoproduction to be 0.010+/-0.002+/-0.001, which is much higher than in Au-Au collisions at a similar nucleon-nucleon centre-of-mass energy. No significant production of particles heavier than deuterons is observed and upper limits are set on the photoproduction cross sections for such particles.
AB - The cross section for anti-deuteron photoproduction is measured at HERA at a mean centre-of-mass energy of W-gammap=200 GeV in the range 0.2 <p(T)/M <0.7 and \y\ <0.4, where M, p(T) and y are the mass, transverse momentum and rapidity of the anti-deuteron in the HERA laboratory frame, respectively. The numbers of anti-deuterons per event are found to be similar in photoproduction to those in central proton-proton collisions at the CERN ISR but much lower than those in central Au-Au collisions at RHIC. The coalescence parameter B-2, which characterizes the likelihood of anti-deuteron production, is measured in photoproduction to be 0.010+/-0.002+/-0.001, which is much higher than in Au-Au collisions at a similar nucleon-nucleon centre-of-mass energy. No significant production of particles heavier than deuterons is observed and upper limits are set on the photoproduction cross sections for such particles.
U2 - 10.1140/epjc/s2004-01978-x
DO - 10.1140/epjc/s2004-01978-x
M3 - Article
VL - 36
SP - 413
EP - 423
JO - European Physical Journal C
JF - European Physical Journal C
IS - 4
ER -