Beam loss rates with an internal gas target in an electron-cooled storage ring Implications for luminosity optimization

Measurements have been made in the Cooler ring at the Indiana University Cyclotron Facility (IUCF) of the mean lifetime of stored and electron-cooled proton beams in the presence of various target gas species at two ring locations differing in dispersion. A broad range of beam energy T_b, target atomic number Z_t and thickness x_t was employed. The loss (removal) cross sectionσ_L per target atom, extracted from the lifetime measurement, exhibits a minimum for small x_t which is found to scale with . This behavior is expected because forward Coulomb scattering from target nuclei should be the dominant loss mechanism under the conditions of measurement. A marked increase in σ_L for larger x_t is attributed to emittance growth arising from multiple scattering in competition with the transverse cooling rate. Lattice dispersion at the target increases the contribution to beam heating by electrons in the target atoms and introduces an additional loss mechanism. From the measured σ_L and beam lifetime, a time cycle may be selected which gives the optimum time-averaged luminosity for a given experiment. Scaling of σ_L allows prediction of the optimum luminosity over the full operating regime of the cooling ring.     

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Superconducting properties of ion beam modified YBCO microbridges

We prepared ion beam modified microbridges based on thin sputtered or laser ablated YBCO films on SrTiO₃ substrates. The microbridges with a width of 10 μm were irradiated through slits in a 700 nm thick double layer resist mask. In our experiments we used O⁺ ions with an ion energy of 30 keV or 100 keV varying the dose between 10¹³ ions·cm⁻² and 10¹⁴ ions·cm⁻². We investigated the influence of film thickness and slit width on the superconducting properties of these junctions. We show the temperature dependence of the junctions properties on microwave radiation or external magnetic fields.     

The diagnostic and treatment characteristics of gunshot wounds to the organs of the urinary system in modern wars

The frequency of injuries of the urinary system which are very severe is as high as 4% of all the wounds of other localizations. The high frequency of associated injuries, critical states of the wounded give very short time for urological examinations which prevents making the exact diagnosis. Nephrectomy still remains the most common operative intervention for wounds of the kidneys (62.8%). The insufficient elimination of urine and inadequate drainage in wounds of the urinary bladder and urethra are followed by very severe complications. An analysis of the experience with treatment of wounds of the urinary system has shown that the medical evacuatory measures must be improved.     

Design concept for radiation hardening of low power and low voltagedynamic memories

A radiation hard low power, low voltage dynamic memory is obtained by the use of a dummy cell concept. Compared to conventional dummy cell concepts, this concept applies a fully sized dummy cell. By optimizing the dummy cell precharge voltage for 5 V and 3 V operation and the timing of the dummy word-line, the overall soft error rate (SER) of the chip is improved by 2 orders of magnitude. An additional improvement of 1 order of magnitude is possible for 3 V operation by adjusting substrate bias and cell plate voltage. The results are verified by an accelerated SER measurement with a radium 226 source and an additional field soft error study