TY  - CONF
AU  - Hoffstaetter, G. H.
AU  - Willeke, F.
TI  - Beam-Beam Limit With Hourglass Effect in HERA
IS  - DESY-M-02-01V
M1  - PUBDB-2016-04123
M1  - DESY-M-02-01V
SP  - 401-403
PY  - 2002
AB  - After the design luminosity had been exceeded in the electron–proton collider HERA, the interaction regions have been rebuilt to boost the luminosity by roughly a factor 4 and are now being commissioned. While the specific luminosity is increased by a reduction of the beta functionsat the interaction point and by a reduced horizontal electron emittance, the beam-beam tune shift of the e-beam will be increased and the vertical proton beta function at the interaction point will become comparable to the proton bunch length. To analyze these new beam dynamical conditions, the beam-beam force’s effect on the tune spread and on high order resonances under the presence of the hourglass effect has been investigated, and accelerator studies have been performed in conditions for which the tune spread and the resonance strength are comparable to the luminosity upgrade parameters. In these experiments the nominal beam-beam parameter per experiment has been pushed to a record high of 0.5. Based on these tests, the future performance limits of the HERA e/p collider are discussed. 
T2  - The 8th European Particle Accelerator Conference
CY  - 3 Jun 2002 - 7 Jun 2002, Paris (France)
Y2  - 3 Jun 2002 - 7 Jun 2002
M2  - Paris, France
KW  - talk: Paris 2002/06/03 (INSPIRE)
KW  - electron p: storage ring (INSPIRE)
KW  - luminosity (INSPIRE)
KW  - scattering: beam-beam (INSPIRE)
KW  - betatron oscillation: resonance (INSPIRE)
KW  - beam: width (INSPIRE)
KW  - DESY HERA Stor (INSPIRE)
LB  - PUB:(DE-HGF)29 ; PUB:(DE-HGF)8
DO  - DOI:10.3204/PUBDB-2016-04123
UR  - https://bib-pubdb1.desy.de/record/309982
ER  -