相关论文: Coherent Photon-Pomeron and Photon-Photon Interact…
Ultra-peripheral heavy ion collisions involve long range electromagnetic interactions at impact parameters larger than twice the nuclear radius, where no hadronic nucleon-nucleon collisions occur. The first observation of coherent rho…
The STAR collaboration reports the first observation of exclusive rho^0 photo-production, AuAu->AuAu rho^0, and rho^0 production accompanied by mutual nuclear Coulomb excitation, AuAu->Au*Au*rho^0, in ultra-peripheral heavy-ion collisions.…
Ultra-peripheral collisions (UPC) of heavy-ions involve long range electromagnetic interactions at impact parameters twice larger than the nuclear radius, where no nucleon-nucleon collisions occur. The first measurement of photoproduction…
We report the first observation of coherent rho0 production (AuAu->AuAu rho0) and rho0 production accompanied by mutual nuclear Coulomb excitation (AuAu->Au*Au*rho0),and the observation of coherent e+e- pair production (AuAu->Au*Au*e+e-) in…
Ultra-peripheral heavy ion collisions involve long range electromagnetic interactions at impact parameters larger than twice the nuclear radius, where the strong nucleon-nuecleon interactions are uneffective. We present recent results from…
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…
We report the first observation of exclusive $\rho$ production in ultra-peripheral collisions at RHIC. The $\rho$ are produced electromagnetically at large impact parameters where no hadronic interactions occur. The produced $\rho$ have a…
Ultra-peripheral heavy ion collisions involve long range electromagnetic interactions at impact parameters larger than twice the nuclear radius, where no nucleon-nucleon collisions occur. We report on the first observation of rho meson…
We report measurements for coherent rho^0 production, AuAu->AuAu rho^0, and coherent rho^0 and e^+e^- pair production accompanied by mutual nuclear Coulomb excitation, AuAu->Au*Au* rho^0 and AuAuee, in ultra-peripheral relativistic…
Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR collaboration presents a measurement of rho^0 and direct pi^+pi^- photoproduction in ultra-peripheral…
Ultra-peripheral collisions (UPCs) of ions allow us to study photonuclear and two-photon interactions at energies above those available at fixed target accelerators. For heavy ions, the couplings are large enough so that multi-photon…
We present recent STAR results on photoproduction in ultra-peripheral relativistic heavy ion collisions. In these collisions the impact parameter of the beam particles is larger than the sum of their nuclear radii, so that they interact via…
In ultra-peripheral relativistic heavy ion collisions the beam ions scatter at impact parameters larger than the sum of their radii, so that they interact via long range electromagnetic forces. Due to the Lorentz-boost of the beam…
At the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory and at the Large Hadron Collider (LHC) at CERN, particles will be produced in coherent and diffractive nuclear interactions. In extremely peripheral nuclear…
Moving highly-charged ions carry strong electromagnetic fields that act as a field of photons. In collisions at large impact parameters, hadronic interactions are not possible, and the ions interact through photon-ion and photon-photon…
The strong electromagnetic fields of heavy nuclei can produce a wide variety of two-photon and photonuclear reactions at relativistic ion colliders. We present recent results from the STAR collaboration on these `ultra-peripheral'…
Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent…
Ultrarelativistic heavy ion beams carry large electromagnetic and strong absorptive fields, allowing exploration of a variety of physics. Two-photon, photon-Pomeron, and double Pomeron interactions can probe a huge variety of couplings and…
This paper deals with so-called Ultra-Peripheral Collisions (UPCs) of heavy ions. These can be defined as collisions in which no hadronic interactions occur because of the large spatial separation between the projectile and target. The…
In 2010, the STAR Collaboration collected 38 million low-multiplicity triggers for ultra-peripheral collision studies. We present new results involving photonuclear interactions in ultra-peripheral relativistic heavy ion collisions (UPCs),…