A. Moeller

Abstract We present accretion disk size measurements for 15 luminous quasars at 0.7 ≤ z ≤ 1.9 derived from griz light curves from the Dark Energy Survey. We measure the disk sizes with continuum reverberation mapping using two methods, both of which are derived from the expectation that accretion disks have a radial temperature gradient and the continuum emission at a given radius is well described by a single blackbody. In the first method we measure the relative lags between the multiband light curves, which provides the relative time lag between shorter and longer wavelength variations. From this, we are only able to constrain upper limits on disk sizes, as many are consistent with no lag the 2 σ level. The second method fits the model parameters for the canonical thin disk directly rather than solving for the individual time lags between the light curves. Our measurements demonstrate good agreement with the sizes predicted by this model for accretion rates between 0.3 and 1 times the Eddington rate. Given our large uncertainties, our measurements are also consistent with disk size measurements from gravitational microlensing studies of strongly lensed quasars, as well as other photometric reverberation mapping results, that find disk sizes that are a factor of a few (∼3) larger than predictions.

Our aim was to assess whether past discharges from a wastewater treatment plant increased metal pollutant loads in stream mobile species in a one-day baseline sampling study that included a coastal wetland. Mosquitofish (Gambusia affinis) of two sizes, black bullhead (Ameiurus melas), and crayfish (Pacifastacus leniusculus) were collected from Malibu Creek, and California killifish (Fundulus parvipinnis) of three sizes, as well as arroyo chub (Gila orcutti) were sampled from Malibu Lagoon near Los Angeles, California. Species from each locality were pooled by length, homogenized, digested by microwave wet ashing, and analyzed by simultaneous inductively coupled plasma atomic emission spectroscopy for 27 elements. Lagoon killifish 2.0-3.5 cm long contained levels of arsenic and lead above the levels for 95% of California fish, the EDL95. Black bullhead upstream of the discharge contained elevated levels of As, Cr and Se. Young mosquitofish <3 cm in length upstream of the discharge differed greatly in the order of abundance of their elements relative to larger mosquitofish and to other species collected. More sampling than this baseline study allowed was needed to determine if the wastewater treatment plant was a pollution source.

Four catfish fillet homogenate treatments before multielemental metal analysis by simultaneous inductively coupled plasma/atomic emission spectroscopy were compared in triplicate. These treatments were: nitric acid wet-ashing by Parr bomb digestion; nitric acid wet-ashing by microwave digestion; tetramethylammonium hydroxide/nitric acid wet digestion; and dry-ashing. The tetramethylammonium hydroxide/nitric acid method was imprecise (coefficients of variation > 20%). The dry-ashing method was fast and sensitive but had low recoveries of 50% for spiked Pb and Al and was not as precise as the Parr bomb or microwave treatments. The Parr bomb method was the most precise method but was less sensitive than the microwave method which had nearly the same precision. The microwave method was then adapted to homogenates of small whole fish < or = 3 cm in length. The whole fish homogenate required more vigorous digestion conditions, and addition of more acid after the evaporative step because of the presence of less oxidizable and acid-soluble components than fillet. The whole fish homogenate was also more heterogeneous than catfish fillet. A quality assurance protocol to demonstrate homogenate uniformity is essential. The use of a non-specialized microwave oven system allowed precise results for fillet and whole fish homogenates.

The Large Hadron Collider (LHC) is going to start taking data with 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">33</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> luminosity, and reach the designed value of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">34</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> in 2013. The LHC luminosity will continue to improve each year, reaching to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">35</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> in 2023. We call this high luminosity era the Super-LHC (SLHC). Hadronic Endcap (HE) calorimeters of the CMS experiment cover the pseudorapidity range of 1.4 ≪ η ≪ 3 on both sides of the CMS detector, contributing to superior jet and missing transverse energy resolutions. As the integrated luminosity of the LHC increases, the scintillator tiles used in the CMS Hadronic Endcap calorimeter will lose their efficiency. The CMS collaboration plans to substitute Quartz plates for the scintillator tiles of the original design. Various tests have proved Quartz to be radiation hard, but the light produced by Quartz comes from Cerenkov process, which yields drastically fewer photons than scintillation. To increase the light collection efficiency, we propose to treat the Quartz plates with radiation hard wavelength shifters, p-terphenyl or 4% gallium doped zinc oxide. The test beam studies revealed a substantial light collection increase on pTp or ZnO:Ga deposited Quartz plates. We constructed a 20 layer calorimeter prototype with pTp coated plates, and tested the hadronic and the electromagnetic capabilities at the CERN H2 area. Here we report the results of these test beams as well as radiation damage studies performed on p-Terphenyl.

The quartz plate calorimeters are considered as hadronic calorimeter options for upgrading Large Hadron Collider experiments. Previous studies have shown that quartz can resist up to 12 MGy of proton irradiation. Using uniformly distributed wavelength shifting fibers embedded the quartz plates are shown to solve the problem of low visible light production on Cherenkov process. Here, we report the performance tests of a 20-layer quartz plate calorimeter prototype, which is constructed with this approach. The calorimeter prototype was tested at CERN H2 area in hadronic and electromagnetic configuration, at various energies of pion and electron beams. We report the beam test and simulation results of this prototype, we also discuss future improvement directions on manufacturing radiation hard wavelength shifting fibers for this type of hadronic calorimeter design.

An investigation of defocused beam broadening by feed displacement in a parabolic reflector and its potential use as an acquisition means in a monopulse tracking antenna system is presented. The emphasis of the investigation is in the amplitude and phase characteristics of the sum and difference patterns as a function of both feed displacement and sum pattern taper. The investigation, which was performed both analytically and experimentally, shows that when feed defocusing is employed to achieve a beamwidth increase in excess of five times the defocused beamwidth, multiple nulls form in the difference pattern. Since these nulls are positioned relatively close to the beam center, acquisition is still possible under these conditions and the resulting tracking error should be tolerable for most telemetry and communication applications.

Abstract At the beginning of the 21st century, there has been recent development, in human historical terms, of substances that can cause serious harm to human health, and also development of remarkable new analytical technologies capable of detecting substances at the atomic level. Despite this, Australia, though an advanced country, has not implemented any mandatory water quality standards or developed a program similar to well established U.S. or European programs. Presented in this paper is an analysis of the statutory regulatory methods for domestic water in mainland Australia. First, the paper briefly reviews the need for mandatory regulations as opposed to voluntary guidelines. Second, the development of guidelines for drinking water by the National Health and Medical Research Council is reviewed, followed by the legislative requirements in each of the five mainland States of Australia. Drinking water guidelines have been used to assist planning and management and were not construed to be legally enforceable mandatory standards. Health Acts in each State remain the primary statutory defenders of water quality, and the variability between Acts is considerable. Third, other legislation that states the necessity of a high quality of water but does not guarantee its deliverance for all uses is referenced as miscellaneous provisions supporting the need for a comprehensive risk reduction water quality program. The main organizations that supply water in Australia are listed along with the nature of their obligations to supply a quality product. Each State has specific water sanctions that attempt to safeguard water quality, but the legal rights of customers have not advanced substantially. The major administrative scheme in Australia that can enforce quality is licensing, and is this limited to the urban regions of Victoria, New South Wales, and Western Australia.

Due to an expected increase in radiation damage under super-LHC conditions, we propose to substitute the scintillator tiles in the original design of the CMS hadronic endcap (HE) calorimeter with quartz plates. Quartz is proved to be radiation hard by various tests, but the light produced by quartz comes from Cerenkov process, and it is 100 times less than scintillation photons. To enhance the light production we treated the quartz plates with p-Terphenyl, and constructed a 20 layers calorimeter prototype. Here, we report the test beam results for hadronic and electromagnetic capabilities of the calorimeter prototype as well as radiation damage results for p-Terphenyl.

In this note we summarize the progress made by the calorimeter simulation task force (CALOTF) over the past year. The CALOTF was established in February 2008 in order to understand and reconcile the discrepancies observed between the CMS calorimetry simulation and test beam data recorded during 2004 and 2006. The simulation has been significantly improved by using a newer version of GEANT4 and an improved physics list for the full CMS detector simulation. Simulation times have been reduced by introducing flexible parameterizations to describe showering in the calorimeter (using a GFLASH-like approach) which have been tuned to the test beam data.

This note describes a study of intermediate and heavy (masses considered 250, 300, 400, 500, 600 and 800 GeV/c) mass Higgs boson production via Weak Boson Fusion (WBF) using the CMS detector at LHC. Having the second largest production cross section, WBF is one of the main process, where the Higgs particle can be found. Evaluated LHC integrated luminosity should be more than 500 fb−1, when the mass of Higgs particle is expected to be in a range 250 400 GeV/c and more than 1000 fb−1 when mass of Higgs particle is expected to be in a range 500 1000 GeV/c. 1) e-mail: alexi.mestvirishvili@cern.ch

Abnormally high energy events were seen in the Hadronic Forward (HF) calorimeter for pion and muon data during testbeam in 2004. Analysis of testbeam data suggested that such events were caused by particles traveling the entire length of HF and striking the photomultiplier (PMT) windows in the readout box behind HF. Charged particles traversing the window of the PMT emit cerenkov radiation, which creates abnormally high energy events in the data. To further study these events, a modification of the existing official CMS HF simulation was created that added the PMT windows to the simulation as sensitive detectors. In agreement with testbeam data, abnormally high energy events in the PMTs were seen in the simulation for muons and pions. The simulation was then extended to jets simulated with Pythia, and then for collision like events as well. PMT hits were seen in both of these cases. Energy sharing between PMTs for long and short fibers in HF as well as timing differences between normal HF events and PMT events were investigated as methods to tag such abnormal events. While both methods were somewhat successful, it was determined that they were not sufficient. The simulation was also modified to use thinner PMT windows. Reducing the thickness of the window reduced the number of PMT hits, and drastically reduced the energy of these hits, bringing most of them below standard jet energy thresholds. These results led to the replacement of the existing PMTs with new PMTs with a smaller, thinner window. Higgs mass reconstruction methods were applied to Monte Carlo datasets for 115 and 130 GeV Higgs produced through vector boson fusion. In these datasets, the Higgs boson decayed to two tau particles, each of which decayed leptonically. The mass reconstruction methods successfully created a peak at the proper mass for both datasets. In addition to creating a Higgs, the vector boson fusion signal also has two forward jets. These jets are not found in the signal of the dominant background processes. By applying forward jet cuts to both the Higgs and the background events, it was possible to drastically improve the signal to background ratio for this channel. The Higgs boson was recently discovered at the LHC with a mass of approximately 125 GeV. As the methods discussed in this study are appropriate only for a low mass Higgs as the one discovered, they may prove useful in more precisely determining the mass of the Higgs.

Zero‐degree calorimeters have limited space and extreme levels of radiation. A simple, low cost, radiation hard design uses tungsten metal as the absorber and a suitable liquid as the Čerenkov radiator. In other applications a PPAC (Parallel Plate Avalanche Counter) operating with a suitable atmospheric‐pressure gas is an attractive active material for a calorimeter. It can be made radiation hard and has sufficient gain in the gas that no electronic components are needed near the detector. It works well even with the highest concentration of shower particles. For this pressure range, R134A (used in auto air conditioners) has many desirable features.