A proposal to study inelastic diffractive processes by observing coherent production of multipion final states from He nuclei

We propose to study the diffraction dissociation of pions into multi-pion final states, by obtaining the missing mass spectra from the reaction: {pi}{sup -} + He {yields} n{pi}{sup -} + (n - 1){pi}{sup +} + He. The missing mass is calculated from a measurement of the he recoil which is observed in a streamer chamber. In this first exploratory experiment we propose to count the outgoing fast particles, and to measure in a very crude fashion their momenta

An International Collaborative Study to establish a WHO Internal Standard for Toxoplasma gondii DNA Nucleic acid amplification technology assays

Seventeen laboratories from 14 countries participated in an international collaborative study to establish a WHO International Standard for Toxoplasma gondii DNA nucleic acid amplification technology (NAT) assays. In all, 20 separate data sets were collected from these laboratories. Five samples, AA which was lyophilised and BB, CC, DD and EE which were liquid preparations, were analysed using several different NAT assays. The mean T. gondii DNA content of each sample was determined from the study. The mean log10 “equivalents”/ml were 6.0 for sample AA, 5.91 for sample BB, 2.88 for sample CC, 3.01 for sample DD and 6.48 for sample EE. Predictions of the stability of the freeze-dried preparation AA indicate that it is extremely stable and suitable for long term use. On the basis of the collaborative study data and the results of the stability studies, the freeze-dried material, AA is proposed the first International Standard for T. gondii DNA NAT assays. The code number of AA is 10/242 and the proposed potency is 1x106 International units per ml based upon this study. Each vial contains the equivalent of 0.5 ml of material, and the content of each vial would be 5x105 IU/ml

Mass and Γ3π0/Γγγ decay branching ratio of the η-meson from the p(γ, η)p reaction

Neat threshold photoproduction of eta-mesons from the proton has been measured at, the MAMI accelerator with the TAPS spectrometer. The mass of the eta-meson was deduced from the threshold energy for eta-photoproduction. The result of m(eta)=(547.12 +/- 0.06 +/- 0.25) MeV supports the low value of the eta-mass reported from a dp -< He-3(eta) measurement at SATURNE in 1992. The eta-decay branching ratio Gamma(3 pi degrees)/Gamma(gamma gamma) was measured to be (0.832 +/-0.005 +/-0.012)

The HITRAN2020 molecular spectroscopic database

The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables, including partition sums, that apply globally to the data. This paper describes the contents of the 2020 quadrennial edition of HITRAN. The HITRAN2020 edition takes advantage of recent experimental and theoretical data that were meticulously validated, in particular, against laboratory and atmospheric spectra. The new edition replaces the previous HITRAN edition of 2016 (including its updates during the intervening years). All five components of HITRAN have undergone major updates. In particular, the extent of the updates in the HITRAN2020 edition ranges from updating a few lines of specific molecules to complete replacements of the lists and also the introduction of additional isotopologues and new (to HITRAN) molecules: SO, CH3F, GeH4, CS2, CH3I and NF3. Many new vibrational bands were added, extending the spectral coverage and completeness of the line lists. Also, the accuracy of the parameters for major atmospheric absorbers has been increased substantially, often featuring sub-percent uncertainties. Broadening parameters associated with the water vapor s ambient pressure were introduced to HITRAN for the first time and are available now for several molecules. The HITRAN2020 edition will continue taking advantage of the relational structure and efficient interface available at www.hitran.org and the HITRAN Application Programming Interface (HAPI). The functionality of both tools has been extended for the new edition