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This Note reports on the first simulations of and spin dynamics in the AGS using the ray-tracing code Zgoubi. It includes lattice analysis, comparisons with MAD, DA tracking, numerical calculation of depolarizing resonance strengths and comparisons with analytical models, etc. It also includes details on the setting-up of Zgoubi input data files and on the various numerical methods of concern in and available from Zgoubi. Simulations of crossing and neighboring of spin resonances in AGS ring, bare lattice, without snake, have been performed, in order to assess the capabilities of Zgoubi in that matter, and are reported here. This yields a rather long document. The two main reasons for that are, on the one hand the desire of an extended investigation of the energy span, and on the other hand a thorough comparison of Zgoubi results with analytical models as the 'thin lens' approximation, the weak resonance approximation, and the static case. Section 2 details the working hypothesis : AGS lattice data, formulae used for deriving various resonance related quantities from the ray-tracing based 'numerical experiments', etc. Section 3 gives inventories of the intrinsic and imperfection resonances together with, in a number of cases, the strengths derived from the ray-tracing.more » Section 4 gives the details of the numerical simulations of resonance crossing, including behavior of various quantities (closed orbit, synchrotron motion, etc.) aimed at controlling that the conditions of particle and spin motions are correct. In a similar manner Section 5 gives the details of the numerical simulations of spin motion in the static case: fixed energy in the neighboring of the resonance. In Section 6, weak resonances are explored, Zgoubi results are compared with the Fresnel integrals model. Section 7 shows the computation of the {rvec n} vector in the AGS lattice and tuning considered. Many details on the numerical conditions as data files etc. are given in the Appendix Section, pages A and sqs.« less

Self4anchored cable4stayed suspension Bridges ，as a new type of bridge is rarely investigated. Based on simulating turbulent wind fields, the effects of some factors such as geometrical nonlinearity, lateral aerodynamic memory effect, and fluctuating wind on main cables on buffeting response of the Dalian Harbor Sea4routine Bridge, a self4anchored cable4stayed su spension with 800m main span, are analyzed and the characteristics of buffeting response for the new type of bridge are summarized. It is worthy of concern in results that fluctuating winds on the cables causes the vibration of main cables and brings coupling vibration of the stiffing girder, which makes a greater effect on the girder of a self4anchored cable4stayed suspension bridge than those on the girder of a general suspension bridge.

Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult: the depolarizing resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions and are not feasible in the AGS since straight sections are too short. Recently, two helical partial snakes have been built and installed in the AGS. With careful setup of optics at injection and along the ramp, this combination can eliminate the intrinsic and imperfection depolarizing resonances encountered during acceleration. This paper presents the accelerator setup and preliminary results.

Polarized protons are accelerated up to 24.3 GeV in the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). To accelerate the beam with preserving the polarization, two different types of helical dipole partial Siberian snake have been installed to the AGS. One is a superconducting magnet (Cold Snake, CSNK), and the other is a normal conducting one (Warm Snake, WSNK). With these snake magnets, the polarization at the AGS extraction achieved 65%. However, the AGS has spin mismatches at the injection and extraction. This description shows calculated results to have better spin matching with using two or three snakes.

Gold ions for the 2007 run [1] of the relativistic heavy ion collider (RHIC) at Brookhaven National Laboratory (BNL) are accelerated in the Tandem,Booster and AGS prior to injection into RHIC. The setup and performance of this chain of accelerators is reviewed with a focus on improvements in the quality of beam delivered to RHIC. In particular,more uniform stripping foils between Booster and AGS,and a new bunch merging scheme in AGS have provided beam bunches with reduced longitudinal emittance for RHIC.

The RHIC spin program requires 2×1011proton/bunch with 70% polarization. As the injector to RHIC, AGS is the bottleneck for preserving polarization: there is no space for a full snake to overcome numerous depolarizing resonances. An ac dipole and a partial snake have been used to preserve beam polarization in the past few years. Two helical snakes have been built and installed in the AGS. With careful setup of optics at injection and along the ramp, this combination can eliminate all depolarizing resonances encountered during acceleration. This paper presents the setup and preliminary results.

Siberian snakes now become essential in the polarized proton acceleration. With proper configuration of Siberian snakes, the spin precession tune of the beam becomes ½ which avoids all the spin depolarizing resonance. However, the enhancement of the perturbations on the spin motion can still occur when the spin precession tune is near some low order fractional numbers, called snake resonances, and the beam can be depolarized when passing through the resonance. The snake resonances have been confirmed in the spin tracking calculations, and observed in RHIC with polarized proton beam. Equipped with two full Siberian snakes in each ring, RHIC provides us a perfect facility for snake resonance studies. This paper presents latest experimental results. New insights are also discussed.

An innovative polarimeter based on proton carbon elastic scattering in the Coulomb Nuclear Interference (CNI) region was first successfully tested in the Brookhaven AGS. CNI Polarimeters were then installed in the AGS and both RHIC rings. The polarimeter consists of ultra‐thin carbon targets and silicon strip detectors. The waveform digitizers used for signal readout allow deadtime‐less data processing on the fly. Polarimeters are crucial instrumentation for the RHIC spin physics program. This paper summarizes the polarimeter design issues and operation results.

Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20 - 30 % partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction.

Relativistic Heavy Ion Collider (RHIC) ended its second year of operation in January 2002 with five weeks of polarized proton collisions. Polarized protons were successfully injected in both RHIC rings and maintained polarization during acceleration up to 100 GeV per ring using two Siberian snakes in each ring. This is the first time that polarized protons have been accelerated to 100 GeV. The machine performance and accomplishments during the polarized proton run will be reviewed. The plans for the next polarized proton run will be outlined.

An 11.4% partial Siberian snake was used to successfully accelerate polarized protons through a strong intrinsic depolarizing spin resonance in the AGS. No noticeable depolarization was observed. This opens up the possibility of using a 20% partial Siberian snake in the AGS to overcome all weak and strong spin resonances.

An 11.4% partial Siberian snake was used to successfully accelerate polarized protons through a strong intrinsic depolarizing spin resonance in the AGS. No noticeable depolarization was observed. This opens up the possibility of using a 20% to 30% partial Siberian snake in the AGS to overcome all weak and strong depolarizing spin resonances. Some design and operation issues of the new partial Siberian snake are discussed.

A new polarimeter based on proton carbon elastic scattering in the CNI (Coulomb Nuclear Interference) region has been proposed for RHIC and one pC CNI polarimeter has been installed in the blue ring of RHIC. This paper summarizes the design and parameters of this new polarimeter. It is a simple, compact, and cost effective polarimeter.

In the recent polarized proton runs in the AGS, a 5% partial snake was used successfully to overcome the imperfection depolarizing resonances. Although some depolarization at intrinsic resonances are expected, the level of the depolarization does not agree with a simple model calculation. A spin tracking program is then used to simulate the real polarized proton beam in the AGS. The results show that, due to the linear coupling introduced by a solenoidal 5% partial snake, the polarized beam will be partially depolarized also at the so-called coupling resonance, which is related to the horizontal betatron tune. The synchrotron oscillation also affect the beam polarization to a smaller extent.

Picture archiving and communication systems (PACS) are now clinically available in limited radiologic applications. The benefits, acceptability, and reliablity of these systems have thus far been mainly speculative and anecdotal. This paper discusses the evaluation of a PACS module implemented in the pediatric radiology section of a 700-bed teaching hospital. The PACS manages all pediatric inpatient images including conventional x-rays and contrast studies (obtained with a computed radiography system), magnetic resonance images, and relevant ultrasound images. A six-monitor workstation is available for image review.

We have integrated a dedicated digital projectional radiographic system for the Chest Radiology Section at UCLA. The system has been running since September, 1988 and is undergoing clinical evaluation. This paper describes the image acquisition, communication, storage, and display components of this system. An implementation of the system as a full PACS module in the Chest Radiology Section is in progress.

A digital optical disk archive has been running continuously in the Pediatric Radiology Section at UCLA for over one year. During this year both the computerized patient registration system and the optical disk image archive have been accumulating patient and image data. Statistics derived from one year's operation are combined with a pediatric film library survey to summarize system use and to project departmental archive requirements. L INTRODUCTION Picture Archiving and Communication Systems (PACS) can succeed in a clinical environment if they are in­ troduced in a modular fashion and are carefully guided in their implementation and growth. The Department of Radiological Sciences at UCLA began full operation of its pediatric PACS acquisition and storage subsystems in November of 1986. The clinical* and technical^ aspects of this system are discussed elsewhere in this volume. This paper presents statistics derived from the pediatric patient and image databases in order to assess and project the growth of the pediatric module. These data are used to predict storage requirements for a department-wide PACS operation.The main databases employed by the clinical PACS are those associated with the Pediatric Radiology Patient Registration System (PRPRS) and the Clinical Radiology Imaging System (CRIS). The former is responsible for registering patient procedures and the latter for image tracking. An analysis of these two related databases provides insight into the patient population in pediatric radiology and the nature of images generated by pediatric procedures. Because pediatric radiology operated without the benefit of digital technology until a year ago, we draw upon a pediatric film library survey to provide additional information on long-term image storage. These three sources of information, PRPRS, CRIS, and the film library provide the basis for this study conducted on data for the year from December 1, 1986 to November 30, 1987.

The details of a clinical PACS module for Pediatric radiology are discussed. The system operates as a large queueing network allowing several processes to execute concurrently in a prioritized and coordinated fashion. This paper presents clinical data accumulated since March 1987 on system workload, system performance, and workstation optimization techniques.

As a critical care unit that functions under strict time constraints, the coronary care unit (CCU) requires rapid access to radiological information of the patient. In order to meet this clinical demand, a digital remote viewing system was developed and has been in clinical operation since March 1987. The system delivers the softcopy of chest images to the intensive care unit. During the nine months of continuous clinical operation, the system was evaluated by analyzing the utilization and performance statistics.

One clinical environment which can immediately benefit from the implementation of a radiologic PACS is the intensive care unit (ICU). Our previous study has demonstrated the feasibility and timeliness of routine image transmission to an ICU. In anticipation of future expansion of this service, we have investigated two different models for a hospital-wide ICU PACS. These models included a centralized and a distributed processing PACS configuration. Their comparison indicated that although the distributed model offers some major advantages over the centralized model, the latter may hold a rightful place in the inter-departmental service, especially if the cost issue is a critical factor.

Establishing control of the image data flow between a computed radiography system and a host computer presents many problems in a centralized PACS system design. Dedicating the main computer of the PACS system to service on-line acquisition devices will soon overload the system, especially when multiple image acquisition units are present. At UCLA, our approach is to distribute the task of buffering the input image data to a smart file server. Using a low-cost microcomputer as our image file server, we can reduce the burden to the central PACS computer when an image is to be acquired. This paper describes the design of the smart file server for a PCR/SP computed radiography system.

A receiver operator characteristic (ROC) experiment designed to evaluate the diagnostic performance of 512, 1024 and 2048 monitors as compared to conventional analog films viewed on a lightbox was conducted. Fifty radiographs, 25 with and 25 without a simulated solitary nodule placed on the lung fields of an anthropomorphic chest phantom were used. These images were interpreted by six radiologists under the following six conditions: 512 and 1024 line resolution both with and without interactive contrast enhancement, and 2048 line resolution with contrast enhancement, and analog film on a conventional lightbox. As determined by the area under the ROC curve, which was the measure of diagnostic accuracy the 512 and 1024 line monitors performed below the analog film, the 2048 line monitor proved to be a viable alternative to the analog film.

A picture archiving and communication system (PACS) module for CT, MR, and US images is being developedin our department. The PACS module is composed of three subsystems: (1) image acquisition, (2) data management, and (3) image display. A digital communication network links these subsystems into a functional unit. The systemhardware configuration is described. Daily and yearly totals for the amount of CT, MR, and US images generatedin our department are provided. The software modules for the system operation are presented. We also report onour previous experience with a MR/US PACS module for a single radiology section. 1. Introduction An increasing number of digital images are being generated by radiology departments. These images are distributed over several locations and therefore retrieval of image for a multi -modality patient is not easy. To improve the situation, a centralized archiving system with distributed viewing stations for CT/MR/US images is being implemented in our department. The system hardware configuration is described in the

A direct link between a clinical pediatric PACS module and a FONAR MRI image network was implemented. The original MR network combines together the MR scanner, a remote viewing station and a central archiving station. The pediatric PACS directly connects to the archiving unit through an Ethernet TCP-IP network adhering to FONAR's protocol. The PACS communication software developed supports the transfer of patient studies and the patient information directly from the MR archive database to the pediatric PACS. In the first phase of our project we developed a package to transfer data between a VAX-111750 and the IBM PC I AT-based MR archive database through the Ethernet network. This system served as a model for PACS-to-modality network communication. Once testing was complete on this research network, the software and network hardware was moved to the clinical pediatric VAX for full PACS integration. In parallel to the direct transmission of digital images to the Pediatric PACS, a broadband communication system in video format was developed for real-time broadcasting of images originating from the MR console to 8 remote viewing stations distributed in the radiology department. These analog viewing stations allow the radiologists to directly monitor patient positioning and to select the scan levels during a patient examination from remote locations in the radiology department. This paper reports (1) the technical details of this implementation, (2) the merits of this network development scheme, and (3) the performance statistics of the network-to-PACS interface.

The experimental study of the single, $A_\text{N}(t)$, and double, $A_\text{NN}(t)$, spin analyzing powers was carried out at The Polarized Atomic Hydrogen Jet Target polarimeter (HJET) at The Relativistic Heavy Ion Collider (RHIC). Large statistics of elastic $pp$ events accumulated during RHIC Runs 2015 ($E_\text{beam}=100\ \text{GeV}$) and 2017 ($E_\text{beam}=255\ \text{GeV}$) allowed us to measure analyzing powers in the CNI region $0.001\lesssim-t\lesssim0.02~\text{GeV}$ with unprecedented precision $|\delta A_\text{N,NN}|\lesssim2\times10^{-4}$. The hadronic single spin-flip $r_5$ and double spin-flip $r_2$ amplitude parameters were reliably isolated. Based on this two beam energies measurement, Pomeron and Regge-pole contributions to the hadronic single- and double- spin-flip amplitudes were evaluated. Extrapolation of the measured $r_5(s)$ to $\sqrt{s}=200\ \text{GeV}$ is in agreement with STAR measurements at this energy. A possibility to use HJET data to search for an Odderon contribution to the spin-flip amplitudes is discussed.

The normal conducting helical dipole partial Siberian snake (warm snake) has been installed in the AGS at BNL. The polarized proton threw the warm snake but it is not perfectly because the warm snake has some hardware error which cause beam offset and deflection angle. This paper reports the measured proton beam orbit in the AGS with the warm snake.