The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform

S K Gupta - One of the best experts on this subject based on the ideXlab platform.

  • measurement of the abundance of radioactive 10 be and other light isotopes in cosmic radiation up to 2 gev nucleon 1 with the balloon borne instrument isomax
    The Astrophysical Journal, 2004
    Co-Authors: T Hams, L M Barbier, M Bremerich, E R Christian, G A De Nolfo, S Geier, H Gobel, S K Gupta
    Abstract:

    The Isotope Magnet Experiment (ISOMAX), a balloon-borne superconducting magnet spectrometer, was designed to measure the isotopic composition of the light isotopes (3 ≤ Z ≤ 8) of cosmic radiation up to 4 GeV nucleon^(-1) with a mass resolution of better than 0.25 amu by using the velocity versus rigidity technique. To achieve this stringent mass resolution, ISOMAX was composed of three major detector systems: a magnetic rigidity spectrometer with a precision drift chamber tracker in conjunction with a three-layer time-of-flight system, and two silica-aerogel Cerenkov Counters for velocity determination. A special emphasis of the ISOMAX program was the accurate measurement of radioactive ^(10)Be with respect to its stable neighbor isotope ^9Be, which provides important constraints on the age of cosmic rays in the Galaxy. ISOMAX had its first balloon flight on 1998 August 4–5 from Lynn Lake, Manitoba, Canada. Thirteen hours of data were recorded during this flight at a residual atmosphere of less than 5 g cm^(-2). The isotopic ratio at the top of the atmosphere for 10Be/9Be was measured to be 0:195 ± 0:036 (statistical) ± 0:039 (systematic) between 0.26 and 1.03 GeV nucleon^(-1) and 0:317 ± 0:109 (statistical) ± 0:042 (systematic) between 1.13 and 2.03 GeV nucleon^(-1). This is the first measurement of its kind above 1 GeV nucleon^(-1). ISOMAX results tend to be higher than predictions from current propagation models. In addition to the beryllium results, we report the isotopic ratios of neighboring lithium and boron in the energy range of the time-of-flight system (up to ~1 GeV nucleon^(-1)). The lithium and boron ratios agree well with existing data and model predictions at similar energies.

R Gearhart - One of the best experts on this subject based on the ideXlab platform.

  • large volume threshold Cerenkov Counters
    Nuclear Science Symposium and Medical Imaging Conference, 1991
    Co-Authors: D Kawall, Z E Meziani, R Gearhart
    Abstract:

    The authors summarize the design of a set of large-volume gas threshold Cerenkov Counters to be used in the fixed target experiment E142 at the Stanford Linear Accelerator Center (SLAC). The Counters are designed to operate at a pion threshold of 13 GeV/c and will use a 4.0-m effective length of CO/sub 2/ at 0.136-atm pressure as a radiator. A 5-in photomultiplier will be used to detect an expected average of 6.5 photoelectrons per electron scattered through the counter. >

T Hams - One of the best experts on this subject based on the ideXlab platform.

  • measurement of the abundance of radioactive 10 be and other light isotopes in cosmic radiation up to 2 gev nucleon 1 with the balloon borne instrument isomax
    The Astrophysical Journal, 2004
    Co-Authors: T Hams, L M Barbier, M Bremerich, E R Christian, G A De Nolfo, S Geier, H Gobel, S K Gupta
    Abstract:

    The Isotope Magnet Experiment (ISOMAX), a balloon-borne superconducting magnet spectrometer, was designed to measure the isotopic composition of the light isotopes (3 ≤ Z ≤ 8) of cosmic radiation up to 4 GeV nucleon^(-1) with a mass resolution of better than 0.25 amu by using the velocity versus rigidity technique. To achieve this stringent mass resolution, ISOMAX was composed of three major detector systems: a magnetic rigidity spectrometer with a precision drift chamber tracker in conjunction with a three-layer time-of-flight system, and two silica-aerogel Cerenkov Counters for velocity determination. A special emphasis of the ISOMAX program was the accurate measurement of radioactive ^(10)Be with respect to its stable neighbor isotope ^9Be, which provides important constraints on the age of cosmic rays in the Galaxy. ISOMAX had its first balloon flight on 1998 August 4–5 from Lynn Lake, Manitoba, Canada. Thirteen hours of data were recorded during this flight at a residual atmosphere of less than 5 g cm^(-2). The isotopic ratio at the top of the atmosphere for 10Be/9Be was measured to be 0:195 ± 0:036 (statistical) ± 0:039 (systematic) between 0.26 and 1.03 GeV nucleon^(-1) and 0:317 ± 0:109 (statistical) ± 0:042 (systematic) between 1.13 and 2.03 GeV nucleon^(-1). This is the first measurement of its kind above 1 GeV nucleon^(-1). ISOMAX results tend to be higher than predictions from current propagation models. In addition to the beryllium results, we report the isotopic ratios of neighboring lithium and boron in the energy range of the time-of-flight system (up to ~1 GeV nucleon^(-1)). The lithium and boron ratios agree well with existing data and model predictions at similar energies.

D Kawall - One of the best experts on this subject based on the ideXlab platform.

  • large volume threshold Cerenkov Counters
    Nuclear Science Symposium and Medical Imaging Conference, 1991
    Co-Authors: D Kawall, Z E Meziani, R Gearhart
    Abstract:

    The authors summarize the design of a set of large-volume gas threshold Cerenkov Counters to be used in the fixed target experiment E142 at the Stanford Linear Accelerator Center (SLAC). The Counters are designed to operate at a pion threshold of 13 GeV/c and will use a 4.0-m effective length of CO/sub 2/ at 0.136-atm pressure as a radiator. A 5-in photomultiplier will be used to detect an expected average of 6.5 photoelectrons per electron scattered through the counter. >

G Eigen - One of the best experts on this subject based on the ideXlab platform.