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Measurements have been performed of scintillation light intensities emitted from various inorganic scintillators irradiated with low-energy beams of highly-charged ions from an electron beam ion source (EBIS) and an electron cyclotron resonance ion source (ECRIS). Beams of xenon ions Xe$^{q+}$ with various charge states between $q$=2 and $q$=18 have been used at energies between 5 keV and 17.5 keV per charge generated by the ECRIS. The intensity of the beam was typically varied between 1 and 100 nA. Beams of highly charged residual gas ions have been produced by the EBIS at 4.5 keV per charge and with low intensities down to 100 pA. The scintillator materials used are flat screens of P46 YAG and P43 phosphor. In all cases, scintillation light emitted from the screen surface was detected by a CCD camera. The scintillation light intensity has been found to depend linearly on the kinetic ion energy per time deposited into the scintillator, while up to $q$=18 no significant contribution from the ions' potential energy was found. We discuss the results on the background of a possible use as beam diagnostics e.g. for the new HITRAP facility at GSI, Germany., Comment: 6 pages, 8 figures

Supercooled liquid and glassy acetyl salicylic acid was studied using dielectric spectroscopy and deuteron relaxometry in a wide temperature range. The supercooled liquid is characterized by major deviations from thermally activated behavior. In the glass the secondary relaxation exhibits the typical features of a Johari-Goldstein process. Via measurements of spin-lattice relaxation times the selectively deuterated methyl group was used as a sensitive probe of its local environments. There is a large difference in the mean activation energy in the glass with respect to that in crystalline acetyl salicylic acid. This can be understood by taking into account the broad energy barrier distribution in the glass., Comment: 8 pages, 3 figures, Submitted to Phys. Rev. E

In April 2001 SN1993J was observed with both the PN and MOS cameras of the XMM-Newton observatory, resulting in about 7. x 10^4 s of acceptable observation time. Fit results with both the PN and MOS2 camera spectra studying different spectral models are presented. The spectra are best fitted in the energy range between 0.3 and 11 keV by a 2-component thermal model with temperatures of kT_1 = 0.34+-0.04 keV and kT_2 = 6.54+-4 keV, adopting ionization equilibrium. A fit with a shock model also provides acceptable results. Combining the XMM-Newton data with former X-ray observations of the supernova, we discuss the general trend of L_x propto t^{-0.30} and the bump of the X-ray light curve as well as former and recent spectral results in the light of the standard SN model as first proposed by Chevalier in 1982., Comment: 7 pages, 3 figures

We report on multi-epoch X-ray observations of the Type IIn (narrow emission line) supernova SN 1995N with the ROSAT and ASCA satellites. The January 1998 ASCA X-ray spectrum is well fitted by a thermal bremsstrahlung (kT~10 keV, N_H~6e20 cm^-2) or power-law (alpha~1.7, N_H~1e21 cm^-2) model. The X-ray light curve shows evidence for significant flux evolution between August 1996 and January 1998: the count rate from the source decreased by 30% between our August 1996 and August 1997 ROSAT observations, and the X-ray luminosity most likely increased by a factor of ~2 between our August 1997 ROSAT and January 1998 ASCA observations, although evolution of the spectral shape over this interval is not ruled out. The high X-ray luminosity, L_X~1e41 erg/sec, places SN 1995N in a small group of Type IIn supernovae with strong circumstellar interaction, and the evolving X-ray luminosity suggests that the circumstellar medium is distributed inhomogeneously., Comment: MNRAS accepted. 6 pages, 2 figures; uses mn.sty and psfig

New high current accelerator facilities like proposed for HIDIF or ESS require a beam with a high brilliance. These beams can not be produced by a single pass rf-linac. The increase in brightness in such a driver linac is done by several funneling stages at low energies, in which two identically bunched ion beams are combined into a single beam with twice the frequency current and brightness. Our Two-Beam-RFQ funneling experiment is a setup of two ion sources, a two beam RFQ, a funnel deflector and beam diagnostic equipment to demonstrate funneling of ion beams as a model for the first funneling stage of a HIIF driver. The progress of the funneling experiment and results of simulations will be presented., Comment: 3 pages, 11 figures

Low-frequency vibrations of glassy and crystalline orthoterphenyl are studied by means of neutron scattering. Phonon dispersions are measured along the main axes of a single crystal, and the corresponding longitudinal and transversal sound velocities are obtained. For glassy and polycrystalline samples, a density of vibrational states is determined and cross-checked against other dynamic observables. In the crystal, low-lying zone-boundary modes lead to an excess over the Debye density of states. In the glass, the boson peak is located at even lower frequencies. With increasing temperature, both glass and crystal show anharmonicity., Comment: 7 pages of LaTeX (svjour), 2 tables, 10 figures accepted in Eur. Phys. J. B

We present the results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT all sky survey (RASS) bright source catalog with optical galaxy catalogs. In this paper we present results from the second optical observing run., Comment: 4 pages LaTeX (modified aa style using pxray_symp.cls), incl. 5 Postscript figures, to appear in: B. Aschenbach et al. (eds.) Highlights in X-ray Astronomy (Garching, June 1998)

We present the first results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT All Sky Survey (RASS) bright source catalog with optical galaxy catalogs. A high X-ray flux has been used as pointer to galaxies with a high probability to contain active nuclei. Only galaxies have been accepted for the program for which no activity was noted in NED. For many of the galaxies no radial velocity was reported before. The optical spectra demonstrate that the galaxies cover a redshift range of 0.014 to 0.13 and that most of them host active nuclei. For 75 percent of the 33 candidates the X-ray emission is caused by the AGN. In addition several of the remaining candidates host Seyfert 2/LINER nuclei that, however, most certainly cannot explain the X-ray emission alone. Three BL Lac objects have been detected serendipitously in galaxy fields that have been followed up by short ROSAT HRI observations to confirm the X-ray galaxy identification with improved position accuracy and point response function. The sources show X-ray to radio flux ratios typical for X-ray selected BL Lac objects. The results presented in the paper prove the selection strategy as very successful to detect previously unknown AGN of all Seyfert 1 types in nearby galaxies encouraging the extension of this program. The detection of new nearby AGN will be used to initiate a detailed investigation of their multi-wavelength properties and a comparison with the more distant AGN population., Comment: 17 pages incl. 5 figures, accepted for publication in Astronomy and Astrophysics, full paper version available at http://www.rosat.mpe-garching.mpg.de/~wnp/