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TECHNICAL DESIGN REPORT OF THE FORWARD SILICON VERTEX (FVTX)
The main goal of the RHIC heavy ion program is the discovery of the novel ultra-hot high-density state of matter predicted by the fundamental theory of strong interactions and created in collisions of heavy nuclei, the Quark-Gluon Plasma (QGP). From measurements of the large elliptic flow of light mesons and baryons and their large suppression at high transverse momentum pT that have been made at RHIC, there is evidence that new degrees of freedom, characteristic of a deconfined QCD medium, drive the dynamics of nucleus-nucleus collisions. It has been recognized, however, that the potential of light quarks and gluons to characterize the properties of the QGP medium is limited and the next phase of the RHIC program calls for the precise determination of its density, temperature, opacity and viscosity using qualitatively new probes, such as heavy quarks. We propose the construction of two Forward Silicon Vertex Trackers (FVTX) for the PHENIX experiment that will directly identify and distinguish charm and beauty decays within the acceptance of the muon spectrometers. The FVTX will provide this essential coverage over a range of forward and backward rapidities (1.2 < |y| < 2.4)--a rapidity range coverage which not only brings significantly larger acceptance to PHENIX but which is critical for separating cold nuclear matter effects from QGP effects and is critical for measuring the proton spin contributions over a significant fraction of the kinematic range of interest. In addition, the FVTX will provide greatly reduced background and improved mass resolution for dimuon events, culminating in the first measurements of the {upsilon}{prime} and Drell-Yan at RHIC. These same heavy flavor and dimuon measurements in p+p collisions will allow us to place significant constraints on the gluon and sea quark contributions to the proton's spin and to make fundamentally new tests of the Sivers function universality
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TECHNICAL DESIGN REPORT FOR A NOSECONE CALORIMETER (NCC) FOR THE PHENIX EXPERIMENT.
A remarkable result has emerged from the first several years of data taking at RHIC--the high temperature and density phase of QCD matter created in heavy ion collisions at RHIC is best described as a near perfect fluid--the strongly interacting Quark-Gluon-Plasma (sQGP). This state is characterized by a small viscosity to entropy ratio, and a high density of color charges which induces huge energy losses of partons transversing the medium. The task for the future is to understand the characteristics of the sQGP, and perhaps more importantly--to gain some insight into how and why such a medium is created. The PHENIX detector has been one of the primary experimental tools at RHIC; in particular the electromagnetic calorimeter has been a critical component of many of the measurements leading to this discovery. The coverage of the present PHENIX electromagnetic calorimeter is rather limited, covering half the azimuth and -0.35< {eta} <0.35 Further progress requires larger coverage of electromagnetic calorimetry, both to increase the rate for low cross section phenomena, and to cover a broader range of pseudorapidity to study the rapidity dependence of the medium. A pair of Nosecone Calorimeters (NCC) has been designed covering both positive and negative rapidity regions 1< |{eta}| <3 of the PHENIX detector. The NCC will make it possible to perform tomographic studies of the jet energy dependence of energy loss and medium response, by using direct photons as trigger particles over a large rapidity range. The technique of correlating trigger hadrons with low momentum hadrons has been powerfully exploited at RHIC to study the evolution of back to back jets [1, 2] and hence the response of the medium. The NCC will make it possible to do such studies using direct photons as the trigger particles. The direct photon in such ''photon-jet'' events tags the transverse momentum of outgoing parton which then fragments into lower energy particles. Together with the Forward Silicon Vertex detector (FVTX), the NCC will make PHENIX a large acceptance spectrometer, capable of detecting photons, electrons, muons, and hadrons. Our prime motivation is to provide precision measurements of direct photons, {pi}{sup 0}s and dielectrons in A+A, p(d)+A, and polarized p+p collisions. The upgrade will provide access to physics observables that are not currently accessible to PHENIX or that are now available only indirectly with very limited accuracy