Search results for "SPECTRA"

Scalar particle contribution to Higgs production via gluon fusion at NLO

2007

22 pages, 5 figures.-- ISI Article Identifier: 000252243700095.-- ArXiv pre-print available at: http://arxiv.org/abs/0709.4227

Charmed hadrons in nuclear medium

2010

5th International Conference on Quarks and Nuclear Physics (QNP09).Inst High Energy Phys Chinese Acad Sci, Beijing, PEOPLES R CHINA, SEP 21-25, 2009

Pinning down QCD-matter shear viscosity in ultrarelativistic heavy-ion collisions via EbyE fluctuations using pQCD + saturation + hydrodynamics

2015

We introduce an event-by-event pQCD + saturation + hydro ("EKRT") framework for high-energy heavy-ion collisions, where we compute the produced fluctuating QCD-matter energy densities from next-to-leading order (NLO) perturbative QCD (pQCD) using saturation to control soft particle production, and describe the space-time evolution of the QCD matter with viscous hydrodynamics, event by event (EbyE). We compare the computed centrality dependence of hadronic multiplicities, p_T spectra and flow coefficients v_n against LHC and RHIC data. We compare also the computed EbyE probability distributions of relative fluctuations of v_n, as well as correlations of 2 and 3 event-plane angles, with LHC d…

On-line laser spectroscopy of short-lived mercury isotopes

1978

The nature of the 4.8 eV optical absorption band induced by vacuum-ultraviolet irradiation of glassy SiO2

2000

Abstract The controversial optical absorption band centered at 4.8 eV, which is present in nearly all irradiated silicas, was investigated. It is caused by at least two different defects: non-bridging oxygen hole center (NBOHC) and interstitial ozone (O3). Both species have absorption bands at 4.8 eV, the O3-related band is identified by its susceptibility to bleaching by 4 to 5 eV photons, by a smaller halfwidth and by its independence from the NBOHC-associated 1.9 eV photoluminescence (PL) band. The contribution of NBOHC to the 4.8 eV band is dominant in most cases, while O3 is important in F2 excimer laser-irradiated samples of oxygen-rich glassy SiO2.

Spectroscopy of 253No and its daughters

2011

Abstract New high-statistics data have been obtained on the decay properties of 253 No and its daughters using the reaction 207 Pb( 48 Ca, 2n) 253 No. This was made possible thanks to an improved transmission of fusion–evaporation residues through the VASSILISSA recoil separator and an increased efficiency of the GABRIELA detector setup. The decay schemes of 253 No and 249 Fm have been revisited. The known level scheme of 249 Fm has been confirmed, including a new level at 669 keV excitation energy. The observation of L X-rays in coincidence with the α decay of 249 Fm gives additional support to the ground-state configuration of 1 / 2 + [ 631 ] instead of 5 / 2 + [ 622 ] for 245 Cf. In both…

Time-resolved luminescence of CsITl crystals excited by pulsed electron beam

1997

Abstract Results of the time-resolved measurements of CsITl crystal luminescence under electron pulse excitation at room temperature are reported. The rise and decay times of both 400 and 500 nm emission bands have been measured. The results obtained show that the main mechanism of the luminescence excitation is hole recombination luminescence which is due to self-trapped hole migration toward Tl 0 centres. Stimulation spectra of photostimulated luminescence of CsITl are also analyzed.

EPR of radiation defects in LiBaF 3 crystals

2002

EPR spectra of LiBaF 3 crystals have been investigated after X-irradiation at RT. A spectrum consisting of approximately 35 nearly equidistant EPR lines has a strong angular dependence on the line intensities. The spectrum is caused by a hyperfine interaction (hfs) of a spin S=1/2 with neighbouring groups of nuclei. The observed large number of hfs lines required Li nuclei being in the first shell and fluorine nuclei in the more distant second shell. We analysed the spectrum in the F-centre model, taking reduced hfs values of the F-centre in LiF and found qualitative explanation of the number of hfs lines. The angular dependence of the line intensities could be explained by an anisotropy of…

Pulsed electron beam excited transient absorption in SrTiO3

2002

Abstract Transient absorption (TA) spectra and optical density relaxation kinetics in SrTiO3 (STO), STO–Nb and STO–V were studied. The electron polaron free or bound at intrinsic defect is suggested to be responsible for the TA band at ∼1.4 eV observed in STO. The band peaking below 0.75 eV in STO–Nb is proposed to be from Nb4+. The electron center V3+ or electron polaron bound in the vicinity of V4+ is responsible for the absorption band at 1.0 eV in STO–V. The absorption from hole polarons is suggested to be in the range 1.8–2.3 eV. It is shown that TA in pure STO at room temperature decays due to electron–hole polaron recombination.

ESD of nonthermal halogen atoms from In-doped (001) KBr

1995

Abstract We have measured the kinetic energy distributions of neutral halogen atoms emitted due to electron-stimulated desorption (ESD) from In-doped (001)KBr single crystals. The concentration of In+ in investigated samples varied between 1017 and 1020 particles/cm3. The measurements were performed at target temperature of 150°C. In all cases the energy spectra consist of two peaks. The distribution of low-energy particles can be described by the thermal (Maxwellian) energy spectrum. Particles contributing to the second peak have nonthermal kinetic energies. The emission of halogen atoms having nonthermal energies decreases with an increase in the concentration of In impurities. At the sam…