[en] A comprehensive field test program was recently completed at several Boiling Water Reactors (BWR) to quantify the effect of coolant impurities on the initiation and growth of stress corrosion cracks. A new technology was utilized which allows for real time monitoring of stress corrosion crack growth rates. The BWR environments were characterized using Ion Chromatography and Electro Chemical Potential (ECP) measurements. The effects of typical water chemistry transients and startups were quantified

[en] In explosive hydrogen burning nucleosynthesis material is processed via the proton capture sequence ³⁹Ca(p,γ)⁴⁰Sc(p,γ)⁴¹Ti. It has been predicted that the isotope ³⁹Ca represents a waiting point for a continuous reaction flow. Therefore, its reaction rate is of interest. The ³⁹Ca(p,γ)⁴⁰Sc reaction rate is determined by three resonances corresponding to the 2nd, 3rd and 4th excited states of ⁴⁰Sc. Improved nuclear structure information of the low-lying levels of ⁴⁰Sc is necessary to reduce uncertainties in the reaction rate of ³⁹Ca(p,γ)⁴⁰Sc. Results from a current measurement of ⁴⁰Ca(³He,t)⁴⁰Sc at TUNL indicate that the 4th excited state is a doublet and further investigation is warranted

[en] Grade 2 meniscal changes on MRI are linear signals confined within the meniscus thought to represent areas of meniscal degeneration or intrasubstance tears. It has been reported that in only 10% of cases is a meniscal tear detected during subsequent arthroscopy. Usually non-operative management is appropriate, but in some cases, grade 2 meniscal changes are seen on MRI in patients with a typical presentation of a meniscal tear. In this circumstance, an arthroscopic partial meniscectomy may be indicated and an MRI report, which describes the meniscus as being normal, may be confusing. A pilot study of 10 consecutive symptomatic patients (mean age 28.1 years) with a grade 2 meniscal signal on MRI was performed. At arthroscopy, with thorough examination of the meniscus using a probe, an intrasubstance tear was detected in all 10 patients. Partial meniscectomy was performed, with a mean follow-up of 6.7 months. All but one patient (due to other pathology) had marked improvement in pain and function. Thus, the authors believe that grade 2 signal changes should be reported in a manner that raises the possibility that they may cause symptoms and that the presence of any intrasubstance changes should be clearly conveyed in the report.

[en] The diameter of Betelgeuse (α Orionis) has been measured at a wavelength of 11.15 μm using the Infrared Spatial Interferometer over the past 15 years. During this 1993-2009 time period the star's size has decreased systematically by 15%.

[en] In the endcaps of the Cherenkov Ring Imaging Detectors for SLD, photoelectrons drift under the influence of crossed electric and magnetic fields. The geometry of the encap design is closely coupled to the Lorentz angle in the chosen drift gas. In this report, we present recent measurements of Lorentz angles and drift velocities in gases suitable for the CRID photon detectors. We compare these measurements to predictions from a theoretical model; good agreement is observed. Based on our results we present a design for detectors operating in a 0.6 T transverse magnetic field. (orig.)

[en] We report on the electrostatic design and related measurements of the barrel Cherenkov Ring Imaging Detector for the Stanford Large Detector experiment at the Stanford Linear Accelerator Center Linear Collider. We include test results of photon feedback in TMAE-laden gas, distortion measurements in the drift boxes and corona measurements. 13 refs., 21 figs

[en] We report the recent progress of the SLD Cherenkov Ring Imaging Detector. All of the individual components of the device (TPCs, mirrors, liquid radiator trays) have been completed and installed. Almost half of the electronics packages are installed and operational, and the data acquisition system has been commissioned. The liquid C₆F₁₄ recirculation system is functioning. The drift gas supply systems are operating well with TMAE, and the gaseous freon C₅F₁₂ recirculator is being brought on-line. Our monitor and control systems are fully functional. The commissioning of all 40 TPCs at full operating voltage has gone very smoothly. The system shows a remarkable immunity to the SLC backgrounds, and yields very clean events, while operating with a single electron sensitivity. 9 refs., 2 figs

[en] We obtained spectra in the wavelength range λ = 995-1769 nm of all four known planets orbiting the star HR 8799. Using the suite of instrumentation known as Project 1640 on the Palomar 5 m Hale Telescope, we acquired data at two epochs. This allowed for multiple imaging detections of the companions and multiple extractions of low-resolution (R ∼ 35) spectra. Data reduction employed two different methods of speckle suppression and spectrum extraction, both yielding results that agree. The spectra do not directly correspond to those of any known objects, although similarities with L and T dwarfs are present, as well as some characteristics similar to planets such as Saturn. We tentatively identify the presence of CH₄ along with NH₃ and/or C₂H₂, and possibly CO₂ or HCN in varying amounts in each component of the system. Other studies suggested red colors for these faint companions, and our data confirm those observations. Cloudy models, based on previous photometric observations, may provide the best explanation for the new data presented here. Notable in our data is that these presumably co-eval objects of similar luminosity have significantly different spectra; the diversity of planets may be greater than previously thought. The techniques and methods employed in this paper represent a new capability to observe and rapidly characterize exoplanetary systems in a routine manner over a broad range of planet masses and separations. These are the first simultaneous spectroscopic observations of multiple planets in a planetary system other than our own.

[en] A brief summary of the design goals, description, and performance of the BABAR Silicon Vertex Tracker is given. Results from radiation hardness tests are discussed, which indicate satisfactory operation up to 5 Mrad of accumulated radiation. The local alignment procedure has made significant improvements recently, and four readout sections were recovered during the BABAR shutdown in 2002

[en] The Silicon Vertex Tracker (SVT) of the BABAR experiment at the PEP-II asymmetric B factory is a crucial element of the BABAR physics program. The SVT is a five layer device with double-sided silicon strip detectors and a custom readout chip based on a time-over-threshold circuit. The SVT is fully operational since the installation in the experiment in 1999. We briefly review the detector performance after more than 3 years of data taking in factory mode. The high-luminosity running of PEP-II through the end of the decade will increase the radiation level in the SVT above its design limit. Radiation issues will be reviewed and results from radiation tests of the various detector components will be presented. We finally discuss the outlook for the long-term running of the SVT