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Related papers: Gamma strength functions and the Brink-Axel hypoth…

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We study X-ray and soft gamma-ray spectral properties of BLRGs using data from Ginga, ASCA, OSSE and EXOSAT. The X-ray spectra are well fitted by an intrinsic power-law continuum with an energy index of alpha ~ 0.7, moderately absorbed by a…

Stable and unstable nuclei with neutron excess ($N>Z$) show - in the isovector dipole transition strength distribution - a small hump around the neutron emission threshold energy known as Pygmy Dipole Resonance (PDR). One of its main…

Nuclear Theory · Physics 2022-02-16 Edoardo G. Lanza , Andrea Vitturi

Dipole excitations in neutron-rich nuclei below the neutron threshold are investigated. The method is based on Hartree-Fock-Bogoliubov (HFB) and Quasiparticle-Phonon Model (QPM) theory. Of our special interest are the properties of the…

Nuclear Theory · Physics 2015-06-26 N. Tsoneva , H. Lenske , Ch. Stoyanov

We propose a new method to analyze fluctuations in the strength function phenomena in highly excited nuclei. Extending the method of multifractal analysis to the cases where the strength fluctuations do not obey power scaling laws, we…

Nuclear Theory · Physics 2009-10-31 Hirokazu Aiba , Masayuki Matsuo

The level density and gamma-ray strength function of 45Ti have been determined by use of the Oslo method. The particle-gamma coincidences from the 46Ti(p,d gamma)45Ti pick-up reaction with 32 MeV protons are utilized to obtain gamma-ray…

The $\gamma$-ray strength function of $^{56}$Fe has been measured from proton-$\gamma$ coincidences for excitation energies up to $\approx 11$ MeV. The low-energy enhancement in the $\gamma$-ray strength function, which was first discovered…

The $\gamma$-ray strength function and the nuclear level density of $^{167}$Ho have been extracted using the Oslo method from a $^{164}\text{Dy}(\alpha,p\gamma)^{167}$Ho experiment carried out at the Oslo Cyclotron Laboratory. The level…

We review and compare the reconstruction methods of the inclusive deep inelastic scattering variables used at HERA. We introduce a new prescription, the $\Sigma$ method, which allows to measure the structure function of the proton…

High Energy Physics - Experiment · Physics 2009-10-22 Ursula Bassler , Gregorio Bernardi

Inelastic proton scattering at energies of a few hundred MeV and extreme forward angles selectively excites the isovector spin-flip M1 (IVSM1) resonance. A method based on isospin symmetry is presented to extract its electromagnetic…

Nuclear level density and $\gamma$-ray strength functions of $^{121,122}$Sn below the neutron separation energy are extracted with the Oslo method using the ($^3$He,$^3$He$^\prime\gamma$) and ($^3$He,$\alpha \gamma$) reactions. The level…

The observation of the diffuse Galactic gamma ray flux is the most powerful tool to study cosmic rays in different regions of the Galaxy, because the energy and angular distributions of the photons encode information about the density and…

High Energy Astrophysical Phenomena · Physics 2018-08-15 Paolo Lipari , Silvia Vernetto

In the external shock model, gamma-ray burst (GRB) emissions are produced by the energization and deceleration of a thin relativistic blast wave due to its interactions with the circumburst medium (CBM). We study the physical properties of…

Astrophysics · Physics 2009-10-31 Charles D. Dermer , Markus Boettcher , J. Chiang

Inelastic $\alpha$-scattering excitation cross sections are calculated for electric dipole excitations in $^{124}$Sn based on the transition densities obtained from the relativistic quasiparticle time-blocking approximation (RQTBA) in the…

Nuclear Theory · Physics 2015-06-19 Edoardo G. Lanza , Andrea Vitturi , Elena Litvinova , Deniz Savran

The level densities and $\gamma$-ray strength functions of $^{105,106,111,112}$Cd have been extracted from particle-$\gamma$ coincidence data using the Oslo method. The level densities are in very good agreement with known levels at low…

We present a measurement of the branching fraction and photon energy spectrum for the decay B --> X_s gamma using data from the BaBar experiment. The data sample corresponds to an integrated luminosity of 210 fb^{-1}, from which…

High Energy Physics - Experiment · Physics 2010-04-12 The BABAR Collaboration , B. Aubert

The first measurements of the longitudinal proton structure function FL in deep inelastic positron-proton scattering at low Bjorken x are described. Theoretical predictions in higher order QCD and using dipol model calculations are…

High Energy Physics - Experiment · Physics 2008-10-22 Max Klein

We estimate the derivative of a probability density function defined on $[0,\infty)$. For this purpose, we choose the class of kernel estimators with asymmetric gamma kernel functions. The use of gamma kernels is fruitful due to the fact…

Statistics Theory · Mathematics 2015-02-10 L. A. Markovich

A polarized gamma ray emission spread over a sufficiently wide energy band from a strongly magnetized astrophysical object like gamma ray bursts (GRBs) offers an opportunity to test the hypothesis of invisible axion. The axionic induced…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Rubbia , A. S. Sakharov

The principal paradigm for gamma-ray bursts suggest that the prompt transient gamma-ray signal arises from multiple shocks internal to the relativistic expansion. This paper illustrates some properties of diffusive acceleration at…

Astrophysics · Physics 2009-11-10 Matthew G. Baring