The operation of a pressurized ultraviolet photoionization threshold cherenkov counter

Study of a Threshold Cherenkov Counter Based on Silica Aerogels with Low Refractive Indices

To identify π and K in the region of 1.0 ∼ 2.5 GeV/c, a threshold Cherenkov counter equipped with silica aerogels has been investigated. Silica aerogels with a low refractive index of 1.013 have been successfully produced using a new technique. By making use of these aerogels as radiators, we have constructed a Cherenkov counter and have checked its properties in a test beam. The obtained resul...

Photoionization of helium above the n = 2 photoionization threshold

2014 Using the technique of electron spectrometry and the synchrotron radiation of the storage ring ACO, the photoionization of helium has been investigated between 69 and 150 eV. The probability to leave the residual ion in the n = 2 excited state has been measured as a function of photon energy. The absolute partial photoionization cross section for this process has been determined and found ...

Sealing of Rotary Drums for Operation Under Pressurized Conditions

Vacuum ultraviolet photoionization of carbohydrates and nucleotides.

Carbohydrates (2-deoxyribose, ribose, and xylose) and nucleotides (adenosine-, cytidine-, guanosine-, and uridine-5(')-monophosphate) are generated in the gas phase, and ionized with vacuum ultraviolet photons (VUV, 118.2 nm). The observed time of flight mass spectra of the carbohydrate fragmentation are similar to those observed [J.-W. Shin, F. Dong, M. Grisham, J. J. Rocca, and E. R. Bernstei...

Photofragmentation of Isoleucine by Vacuum Ultraviolet Photoionization

Vacuum ultraviolet photon-induced ionization and dissociation of isoleucine are investigated with synchrotron radiation photoionization mass spectroscopy and theoretical calculations. The main fragment ions at m/z=86, 75, 74, 69, 57, 46, 45, 44, 41, 30, 28, and 18 from isoleucine are observed in the mass spectrum at the photon energy of 13 eV. From the photoionization efficiency curves, appeara...