Abstract
We present a summary of recent photoproduction results in ultra peripheral relativistic heavy ions collisions with STAR. These collisions have impact parameters larger then twice the nuclear radius; the nuclei do not physically collide, but interact via long-range electromagnetic fields. We observe exclusive ρ0 production as well as AuAu → Au*Au*ρ0 with accompanying mutual nuclear excitation at sqrt(sN N) = 200 GeV. We report the ρ0 production cross section for both coherent and incoherent coupling accompanied by mutual nuclear excitation. We have studied the cross section as a function of pT, yρ0 and Mππ and compared it to theoretical models. In addition, we measured the ρ0 helicity matrix elements. They are found to be consistent with s-channel helicity conservation. The ratio of coherent ρ0 and direct π+π- pair photoproduction has been measured and found to be consistent with earlier measurements. The 4-pion final state AuAu → π+π-π+π- state has also been observed.
| Original language | English |
|---|---|
| Pages (from-to) | 152-157 |
| Number of pages | 6 |
| Journal | Nuclear Physics B - Proceedings Supplements |
| Volume | 184 |
| Issue number | C |
| DOIs | |
| State | Published - Nov 2008 |
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All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
Cite this
Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR. / Seger, Janet E.
In: Nuclear Physics B - Proceedings Supplements, Vol. 184, No. C, 11.2008, p. 152-157.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR
AU - Seger, Janet E.
PY - 2008/11
Y1 - 2008/11
N2 - We present a summary of recent photoproduction results in ultra peripheral relativistic heavy ions collisions with STAR. These collisions have impact parameters larger then twice the nuclear radius; the nuclei do not physically collide, but interact via long-range electromagnetic fields. We observe exclusive ρ0 production as well as AuAu → Au*Au*ρ0 with accompanying mutual nuclear excitation at sqrt(sN N) = 200 GeV. We report the ρ0 production cross section for both coherent and incoherent coupling accompanied by mutual nuclear excitation. We have studied the cross section as a function of pT, yρ0 and Mππ and compared it to theoretical models. In addition, we measured the ρ0 helicity matrix elements. They are found to be consistent with s-channel helicity conservation. The ratio of coherent ρ0 and direct π+π- pair photoproduction has been measured and found to be consistent with earlier measurements. The 4-pion final state AuAu → π+π-π+π- state has also been observed.
AB - We present a summary of recent photoproduction results in ultra peripheral relativistic heavy ions collisions with STAR. These collisions have impact parameters larger then twice the nuclear radius; the nuclei do not physically collide, but interact via long-range electromagnetic fields. We observe exclusive ρ0 production as well as AuAu → Au*Au*ρ0 with accompanying mutual nuclear excitation at sqrt(sN N) = 200 GeV. We report the ρ0 production cross section for both coherent and incoherent coupling accompanied by mutual nuclear excitation. We have studied the cross section as a function of pT, yρ0 and Mππ and compared it to theoretical models. In addition, we measured the ρ0 helicity matrix elements. They are found to be consistent with s-channel helicity conservation. The ratio of coherent ρ0 and direct π+π- pair photoproduction has been measured and found to be consistent with earlier measurements. The 4-pion final state AuAu → π+π-π+π- state has also been observed.
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U2 - 10.1016/j.nuclphysbps.2008.09.154
DO - 10.1016/j.nuclphysbps.2008.09.154
M3 - Article
VL - 184
SP - 152
EP - 157
JO - Nuclear and Particle Physics Proceedings
JF - Nuclear and Particle Physics Proceedings
SN - 2405-6014
IS - C
ER -