In the Daya Bay Reactor Neutrino Experiment 960 20-cm-diameter waterproof photomultiplier tubes are used to instrument three water pools as Cherenkov detectors for detecting cosmic-ray muons. Of these 960 photomultiplier tubes, 341 are recycled from the MACRO experiment. A systematic program was undertaken to refurbish them as waterproof assemblies. In the context of passing the water leakage check, a success rate better than 97% was achieved. Details of the design, fabrication, testing, operation, and performance of these waterproofed photomultiplier-tube assemblies are presented.

As one of the main components of the injector II of China ADS LINAC project, an RFQ working at 162.5MHz is used to accelerate proton beams of 15mA from 30 keV to 2.1 MeV. The four vane RFQ has been designed in collaboration with Lawrence Berkeley National Laboratory and built at the workshop of the Institute of Modern Physics, Chinese Academy of Sciences (IMP, CAS). Low power test of the cavity has been completed, and it shows the field flatness is within ±1% and the unloaded Q is 12600. RF conditioning has been completed, results of preliminary beam test show the output beam energy is 2.16 MeV with energy spread of 3.5% and the transmission efficiency is 97.9%. Continuous wave (CW) beam of 2.3 mA has been accelerated for more than one hour.

The Daya Bay reactor antineutrino experiment is designed to make a precision measurement of the neutrino mixing angle theta13, and recently made the definitive discovery of its nonzero value. It utilizes a set of eight, functionally identical antineutrino detectors to measure the reactor flux and spectrum at baselines of 300 - 2000m from the Daya Bay and Ling Ao Nuclear Power Plants. The Daya Bay antineutrino detectors were built in an above-ground facility and deployed side-by-side at three underground experimental sites near and far from the nuclear reactors. This configuration allows the experiment to make a precision measurement of reactor antineutrino disappearance over km-long baselines and reduces relative systematic uncertainties between detectors and nuclear reactors. This paper describes the assembly and installation of the Daya Bay antineutrino detectors.

We describe a non-contact optical measurement method used to determine the surface flatness of a cryogenic sensor array developed for the JDEM mission. Large focal planes envisioned for future visible to near infra-red astronomical large area point-source surveys such as JDEM, WFIRST, or EUCLID must operate at cryogenic temperatures while maintaining focal plane flatness within a few 10's of μm over half-meter scales. These constraints are imposed by sensitivity conditions that demand low noise observations from the sensors and the large-field, fast optical telescopes necessary to obtain the science yield. Verifying cryogenic focal plane flatness is challenging because μm level excursions need to be measured within and across many multi-cm sized sensors using no physical contact and while situated within a high-vacuum chamber. We have used an optical metrology Shack-Hartmann scheme to measure the 36x18 cm focal plane developed for the JDEM mission at the Lawrence Berkeley National Laboratory. The focal plane holds a 4x8 array of CCDs and HgCdTe detectors. The flatness measurement scheme uses a telescope-fed micro-lens array that samples the focal plane to determine slope changes of individual sensor zones.

PRELIMINARY CONCEPT FOR THE PROJECT X CW RADIO- FREQUENCY QUADRUPOLE (RFQ)* S. P. Virostek, M . D. Hoff, D. L i , and J. W. Staples Lawrence Berkeley National Laboratory, Berkeley, C A , USA Abstract Project X is a proposed multi-MW proton facility at Fermi National Accelerator Laboratory [1]. It is the key element for future accelerator complex development intended to support world-leading High Energy Physics (HEP) programs. The Project X front-end would consist of an H - ion source, a low-energy beam transport ( L E B T ) , a radio-frequency quadrupole (RFQ) accelerator, and a medium-energy beam transport (MEBT). To support current and future H E P experiments at Fermilab, a C W RFQ is required. One of the chosen R F Q designs has a resonant frequency of 325 M H z . A 162.5 M H z option is also being considered but is not presented here. The R F Q provides bunching of the 10 mA H - beam with acceleration from 30 keV to 2.5 M e V and wall power losses of less than 250 kW. Lawrence Berkeley National Laboratory ( L B N L ) is currently developing the early designs for various components in the Project X front-end [2]. The R F Q design concept and the preliminary thermal analyses are presented here. INTRODUCTION The Project X baseline R F Q design is 2.66 m long and will accelerate a 10 mA H - beam to 2.5 M e V , with a 64 kV vane-to-vane voltage (corresponding to a 1.55 Kilpatrick peak field). Most of the RF input power is dissipated on the cavity walls to establish the needed RF field with only about 17% of the total power transferred to the beam. Each of the two 1.33 m long R F Q modules will consist of four solid O F H C copper vanes that are modulated prior to being brazed together. A brazed copper structure has been chosen due to the high power, C W operation. A 304 stainless steel outer shell is to be bolted to the cavity by means of thread inserts in the copper. A series of 32 water-cooled pi-mode rods provides quadrupole mode stabilization, and a set of 48 evenly spaced fixed slug tuners is used for final frequency adjustment and local field perturbation correction. The Project X R F Q design incorporates technology validated by recent RFQ's developed at L B N L , including for the Spallation Neutron Source (SNS) Front End [3] as well as a recent design completed for the Accelerator Driven Neutron Source (ADNS) [4]. The use of proven and reliable fabrication and assembly methods permits construction using readily available machinery incorporating previously proven techniques. The bolt-on, stainless steel outer stiffening plates provide the necessary structural rigidity as well as a means for reliably applying vacuum and RF sealing forces for the tuners, couplers, * This work was supported by the Office of Science, U. S. Department of Energy, under Contract No. DE-AC02-05CH11231. sensing loops and vacuum pumping manifolds. The outer shell also provides for a relatively simple method to interconnect the modules. A preliminary 3-D C A D model of the RFQ conceptual design has been developed and is used here to present a description of the design characteristics. A n overall view of a single R F Q module is shown in Fig. 1. Figure 1: C A D model of a single RFQ module. RFQ DESIGN DETAILS Cavity Body Each of the four vanes in a module are to be machined from a single piece of copper and will include simple cooling channels produced using an established gun boring technique. The R F Q vane tips are to be modulated by means of a fly cutter technique previously developed at L B N L using a commonly available programmable mill. Fiducial surfaces that also act as mating surfaces will be machined directly onto the vanes to provide high precision during both machining and assembly. Two vane geometries will be used (major and minor) with the opposing vanes being identical. Other features such as tuner ports, RF coupling ports, vane cut back cooling passages, cooling taps, vacuum pumping ports, pi-mode rod penetrations, sensing loop ports and tapped holes for the stainless steel backing plates are to be machined prior to finish machining of the cavity surfaces and vane tips. Note that all vacuum seals to the cavity for penetrations are recessed beyond the outer layer of stainless steel and are to be applied directly to the O F H C . The finished vanes are to be brazed together along axially running joints. A zero-thickness brazing process will be used in order to maintain the tight vane tip-to-vane tip tolerance, which is dictated by the high dependence of cavity frequency on vane tip spacing. Wire braze alloy will be loaded into grooves in the joint surfaces such that the alloy spreads throughout the joint during the braze

An over-dense microwave driven ion source capable of producing deuterium (or hydrogen) beams at 100-200 mA/cm 2 with an atomic fraction > 90% was designed as a part of an Accelerator Driven Neutron Source (ADNS). The ion source was tested with an electrostatic low energy beam transport section (LEBT) and measured emittance data was compared to PBGUNS simulations. In our design a 40 mA D + beam is produced from a 6 mm diameter aperture using a 60 kV extraction voltage. The LEBT section consists of 5 electrodes arranged to form 2 Einzel lenses that focus the beam into the REQ entrance. To create the ECR condition, 2 induction coils are used to generate a -875 Gauss magnetic field on axis inside the source chamber. To prevent HV breakdown in the LEBT, a magnetic field clamp is necessary to minimize the field in this region. The microwave power is matched to the plasma by an autotuner. A significant improvement in the atomic fracion of the beam was achieved by installing a boron nitride liner inside the ion source.

A high-yield neutron source to screen sea-land cargo containers for shielded special nuclear materials (SNM) has been designed at LBNL. The Accelerator-Driven Neutron Source (ADNS) uses the D(d,n)3He reaction to create a forward directed neutron beam. Key components are a high-current radio-frequency quadrupole (RFQ) accelerator and a high-power target capable of producing a neutron flux of >107 n/(cm2.s) at a distance of 2.5 m. The mechanical design and analysis of the four-module, bolt-together RFQ will be presented here. Operating at 200 MHz, the 5.1 m long RFQ will accelerate a 40 mA deuteron beam to 6 MeV. At a 5% duty factor, the time-average d+ beam current on target is 1.5 mA. Each of the 1.27 m long RFQ modules will consist of four solid OFHC copper vanes. A specially designed 3-D O-ring will provide vacuum sealing between both the vanes and the modules. RF connections are made with canted coil spring contacts. A series of 60 water-cooled pi-mode rods provides quadrupole mode stabilization. A set of 80 evenly spaced fixed slug tuners is used for final frequency adjustment and local field perturbation correction.

J. Albert, G. Aldering, S. Allam, W. Althouse, R. Amanullah, J. Annis, P. Astier, M. Aumeunier, S. Bailey, C. Baltay, E. Barrelet, S. Basa, C. Bebek, L. Bergström, G. Bernstein, M. Bester, B. Besuner, B. Bigelow, R. Blandford, R. Bohlin, A. Bonissent, C. Bower, M. Brown, M. Campbell, W. Carithers, D. Cole, E. Commins, W. Craig, T. Davis, K. Dawson, C. Day, M. DeHarveng, F. DeJongh, S. Deustua, H. Diehl, T. Dobson, S. Dodelson, A. Ealet, R. Ellis, W. Emmet, D. Figer, D. Fouchez, M. Frerking, J. Frieman, A. Fruchter, D. Gerdes, L. Gladney, G. Goldhaber, A. Goobar, D. Groom, H. Heetderks, M. Hoff, S. Holland, M. Huffer, L. Hui, D. Huterer, B. Jain, P. Jelinsky, C. Juramy, A. Karcher, S. Kent, S. Kahn, A. Kim, W. Kolbe, B. Krieger, G. Kushner, N. Kuznetsova, R. Lafever, J. Lamoureux, M. Lampton, O. Le Fèvre, V. Lebrun, M. Levi, P. Limon, H. Lin, E. Linder, S. Loken, W. Lorenzon, R. Malina, L. Marian, J. Marriner, P. Marshall, R. Massey, A. Mazure, B. McGinnis, T. McKay, S. McKee, R. Miquel, B. Mobasher, N. Morgan, E. Mörtsell, N. Mostek, S. Mufson, J. Musser, R. Nakajima, P. Nugent, H. Olus.eyi , R. Pain, N. Palaio, D. Pankow, J. Peoples, S. Perlmutter, D. Peterson, E. Prieto, D. Rabinowitz, A. Refregier, J. Rhodes, N. Roe, D. Rusin, V. Scarpine, M. Schubnell, M. Seiffert, M. Sholl, H. Shukla, G. Smadja, R. M. Smith, G. Smoot, J. Snyder, A. Spadafora, F. Stabenau, A. Stebbins, C. Stoughton, A. Szymkowiak, G. Tarlé, K. Taylor, A. Tilquin, A. Tomasch, D. Tucker, D. Vincent, H. von der Lippe, J-P. Walder, G. Wang, A. Weinstein, W. Wester, M. White

The Supernova/Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's expansion by performing a series of complementary systematics-controlled astrophysical measurements. We here describe a self-consistent reference mission design that can accomplish this goal with the two leading measurement approaches being the Type Ia supernova Hubble diagram and a wide-area weak gravitational lensing survey. This design has been optimized to first order and is now under study for further modification and optimization. A 2-m three-mirror anastigmat wide-field telescope feeds a focal plane consisting of a 0.7 square-degree imager tiled with equal areas of optical CCDs and near infrared sensors, and a high-efficiency low-resolution integral field spectrograph. The instrumentation suite provides simultaneous discovery and light-curve measurements of supernovae and then can target individual objects for detailed spectral characterization. The SNAP mission will discover thousands of Type Ia supernovae out to z = 3 and will obtain high-signal-to-noise calibrated light-curves and spectra for a subset of > 2000 supernovae at redshifts between z = 0.1 and 1.7 in a northern field and in a southern field. A wide-field survey covering one thousand square degrees in both northern and southern fields resolves {approx} 100 galaxies per square arcminute, or a total of more than 300 million galaxies. With the PSF stability afforded by a space observatory, SNAP will provide precise and accurate measurements of gravitational lensing. The high-quality data available in space, combined with the large sample of supernovae, will enable stringent control of systematic uncertainties. The resulting data set will be used to determine the energy density of dark energy and parameters that describe its dynamical behavior. The data also provide a direct test of theoretical models for the dark energy, including discrimination of vacuum energy due to the cosmological constant and various classes of dynamical scalar fields. If we assume we live in a cosmological-constant-dominated Universe, the matter density, dark energy density, and flatness of space can all be measured with SNAP supernova and weak-lensing measurements to a systematics-limited accuracy of 1%. For a flat universe, the density-to-pressure ratio of dark energy or equation of state w(z) can be similarly measured to 5% for the present value w{sub 0} and {approx} 0.1 for the time variation w' {triple_bond} dw/d ln a|{sub z=1}. For a fiducial SUGRA-inspired universe, w{sub 0} and w' can be measured to an even tighter uncertainty of 0.03 and 0.06 respectively. Note that no external priors are needed. As more accurate theoretical predictions for the small-scale weak-lensing shear develop, the conservative estimates adopted here for space-based systematics should improve, allowing even tighter constraints. While the survey strategy is tailored for supernova and weak gravitational lensing observations, the large survey area, depth, spatial resolution, time-sampling, and nine-band optical to NIR photometry will support additional independent and/or complementary dark-energy measurement approaches as well as a broad range of auxiliary science programs.

Mission requirements, the baseline design, and optical systems budgets for the SuperNova/Accelerafion Probe (SNAP) telescope are presented. SNAP is a proposed space-based experiment designed to study dark energy and alternate explanations of the acceleration of the universe's expansion by performing a series of complementary systematics-controlled astrophysical measurements. The goals of the mission are a Type la supernova Hubble diagram and a wide-field weak gravitational lensing survey. A 2m widefield three-mirror telescope feeds a focal plane consisting of 36 CCDs and 36 HgCdTe detectors and a high-efficiency, low resolution integral field spectrograph. Details of the maturing optical system, with emphasis on structural stability during terrestrial testing as well as expected environments during operations at L2 are discussed. The overall stray light mitigation system, including illuminated surfaces and visible objects are also presented.

LBNL has built for the Spallation Neutron Source (SNS ** ) project a 402.5 MHz RFQ that is designed to accelerate up to 60 mA H from 65 keV to 2.5 MeV [1]. A one millisecond pulse length at 60 Hz provides a 6% duty factor. The RFQ has now been built, conditioned at full duty factor and tested with beam. This paper will present results from the final installation, tuning and beam commissioning. Beam measurements include acceleration and transport efficiencies and transverse emittances. The LEBT optics were tuned for best results. Performance testing of the RF power distribution is also discussed here.

The Lawrence Berkeley National Laboratory (LBNL) is designing and building the 2.5 MeV front end injector for the Spallation Neutron Source (SNS). This injector comprises an H/sup -/ ion source, a low energy beam transport line (LEBT), a radio-frequency quadrupole (RFQ) and a beam transport line designed to provide fast chopping of the beam. The RFQ is designed to accelerate the Hbeam from the energy of 65 keV to 2.5 MeV, while bunching it at 402.5 MHz. This high duty factor (6%) structure is made of a combination of Glidcop and OFE copper and is fully brazed. The RFQ is built in 4 modules, each approximately one meter long. This paper covers the mechanical fabrication details of the modules, three of which have been completed. While the modules are coming out of production, they are conditioned and tested to full power. This paper will also describe the results of the beam tests on the first module, including capture efficiency and transmission.

The Lawrence Berkeley National Laboratory (LBNL) is presently designing and building the 2.5 MeV injector for the Spallation Neutron Source (SNS). This injector comprises an H- ion source, a radio-frequency quadrupole (RFQ) and a beam transport line including a fast chopper. This paper will briefly describe the injector components and then focus on the design and fabrication details of the RFQ, from the beam dynamics, to the mechanical and electrical engineering design. The first module of the RFQ has been built and is presently undergoing tests at LBNL. A status report of the first module is included, describing the completion of the fabrication and low power testing.

The RFQ included in the Front End injector for the Spallation Neutron Source (SNS) operates at 402.5 MHz, with a maximum H/sup -/ input current of 70 mA at a 6% duty factor. It is 3.72 m long and consists of four equally long modules. A brazed copper structure has been chosen due to the high power, high duty factor operation. The 1 MW peak r.f. power is coupled into the structure via eight ports, two per module. Quadrupole mode stabilization is obtained with a set of /spl pi/-mode stabilizing loops. The conceptual design has been completed, and a single, full size prototype RFQ module has been designed and is under construction to test the fabrication processes and r.f. performance. It will be operated at full r.f. power in order to test its cooling scheme, dual temperature water tuning, mode stabilization and beam acceptance. The detailed design, assembly processes, thermal analyses and a status report for the prototype module are presented.

The conceptual design of the RFQ included in the front end injector of the Spallation Neutron Source is described. The RFQ operates at 402.5 MHz, with a maximum H input current of 70 mA and 6% duty factor. It is 3.72 m long and made out of four equally long modules. A brazed copper structure has been chosen due to the high power, high duty factor operation. The 800 kW peak r.f. power is coupled into the structure via eight ports, two per section. A set of tuners is provided for final frequency adjustment and local field perturbation correction. Quadrupole mode stabilization is obtained with a set of π-mode stabilizing loops. The conceptual design, assembly processes and status report are presented. This paper reports and updates the status of the design since it was last described [1].

A 402.5 MHz, 6% duty factor RFQ is being designed for the National Spallation Neutron Source (NSNS). The 6% duty factor and RFQ length will present formidable design challenges. To this end, an RFQ materials test program is underway. A cold model test facility is being designed. Results of cooling calculations have begun. Plans for cavity construction, RF and vacuum seals, alignment, structural support and hot models are discussed