54620466
Measuring the level of nuclear activity in Seyfert galaxies and the unification scheme
Context. The unification scheme of Seyfert galaxies hypothesizes that Seyfert type 1s and type 2s are intrinsically similar and the observed differences between the two subtypes are solely due to the differing orientations of toroidal-shaped obscuring material around the AGN. In the framework of the unification scheme, both the Seyfert subtypes are expected to show similar intrinsic nuclear properties such as the absorption-corrected AGN X-ray luminosity, bolometric luminosity, accretion rate and the mass of the supermassive black hole. Aims. To test the predictions of the Seyfert unification scheme, we make statistical comparison of the distributions of: (i) the absorption-corrected 2.0‐10 keV X-ray luminosities; (ii) the bolometric luminosities; (iii) the black hole masses and; (iv) the Eddington ratios, of Seyfert type 1s and type 2s. Methods. We use an optically selected Seyfert sample in which type 1s and type 2s are matched in properties that are independent to the orientation of the obscuring torus, the AGN axis and the host galaxy. Results. The distributions of the absorption-corrected 2.0‐10 keV X-ray luminosities (L c.0−10 keV ), the bolometric luminosities (LBol), the black masses (MBH) and, the Eddington ratios (λ) are statistically similar for the two Seyfert subtypes, consistent with the orientation and obscuration based Seyfert unification scheme. The Eddington ratio distributions suggest that both the Seyfert subtypes are accreting at sub-Eddington level with wide span of Eddington ratios i.e., 10 −4 ‐10 −1 .
118486527
X-ray spectral properties of Seyfert galaxies and the unification scheme
Context. The unification scheme of Seyfert galaxies predicts that the observed differences between types 1 and 2 Seyfert galaxies are solely due to the differing orientations of the toroidal-shaped obscuring material around AGN. The observed X-ray spectra of Seyfert type 2s compared to type 1s are expected to be affected by higher absorbing column density owing to the edge-on view of the obscuring torus. Aims. We study the 0.5‐10 keV X-ray spectral properties of Seyfert type 1s and type 2s with the aim of testing the predictions of Seyfert unification scheme in the X-ray regime. Methods. We use an optically selected Seyfert sample in which type 1s and type 2s have matched distributions in parameters that are independent of the orientation of AGN and the host galaxy. Results. The 0.5‐10 keV XMM-Newton pn X-ray spectra of Seyfert galaxies are in general best fitted with a model that consists of (i) an absorbed powerlaw; (ii) a narrow Gaussian fitted to the Fe Kα emission line; and (iii) an often seen soft-excess component characterized by either a thermal plasma model with temperature kT ∼ 0.1‐1.0 keV or a steep powerlaw or both. The 2.0‐10 keV hard X-ray continuum emission in several Seyfert type 2s is dominated by reflection and suggests the Compton-thick obscuration. Results of the statistical comparison between the distributions of (i) the observed X-ray luminosities in the soft (0.5‐2.0 keV) and hard (2.0‐10.0 keV) bands; (ii) the X-ray absorbing column densities; (iii) the equivalent widths of Fe Kα line; and (iv) the flux ratios of hard X-ray to [OIII] λ5007 A, for the two Seyfert subtypes are consistent with the obscuration and orientation-based unification scheme.
120676783
HIDDEN VARIABLE THEORIES WITHOUT NONLOCAL SIGNALING AND THEIR EXPERIMENTAL TESTS
We formulate hidden variable theories obeying the local causality condition of absence of faster than light signals, a condition weaker than the Einstein-Bell locality condition. We propose experimental tests of such theories and show that quantum mechanics can be embedded in them.
122336835
Validity of scaling relations between nucleon form factors
We prove, within the framework of analytic S-matrix theory and the physical mass spectrum, that the following scaling relations cannot be rigorously true for all t: (i) G M V (t)∝G E V (t), (ii) G M V (t)=R 1 (t)G E V (t)+R 2 (t), where R 1,2 (t) are rational functions of t, (iii) F Π (t)∝G E V (t), and (iv) F Π (t)∝G M V (t).
118649782
Unitarity restrictions on meson-nucleon helicity-flip amplitudes and slope of the diffraction peak
SummaryWe generalize the MacDowell-Martin bound on the slope parameterbA for the spinless case to the case of spin-0-spin-1/2 elastic scattering with parity conservation. We give the optimal answer for all energies as well as the simpler (slightly weaker) bound

$$cb^A \geqslant \frac{{\sigma _{tot}^2 }}{{36\pi \sigma _{el} }}\left[ {\sqrt {1 + \frac{{9\pi \sigma _{el} }}{{4k^2 \sigma _{tot}^2 }}} + 1} \right] - \frac{1}{{4k^2 }} (k = c.m. momentum).$$

 Here the superscript A refers to the absorptive-part contribution. We also obtain unitarity restrictions on the helicity-flip amplitude

$$cf_{ + - }^A (t)/\sqrt { - t} |_{t = 0} $$

 in terms ofσtot,σel, andbA(s).RiassuntoSi generalizza il limite di McDowell- Martin sul parametro di inclinazionebA per il caso privo di spin fino al caso dello seattering elastico tra spin nullo e spin 1/2 con conservazione della parità. Si dà una risposta ottimale per tutte le energie così come per il limite più semplice (leggermente più debole)

$$cb^A \geqslant \frac{{\sigma _{tot}^2 }}{{36\pi \sigma _{el} }}\left[ {\sqrt {1 + \frac{{9\pi \sigma _{el} }}{{4k^2 \sigma _{tot}^2 }}} + 1} \right] - \frac{1}{{4k^2 }}(k = impulso del centro di massa).$$

 L'esponente A si riferisce al contributo della parte assorbente. Si ottengono restrizioni di unitarietà sull'ampiezza dell'elicità-flip

$$cf_{ + - }^A (t)/\sqrt { - t} |_{t = 0} $$

 in termini diσtot,σel, ebA(S).РезюмеМы обобщаем гранипу МкДовелла-Мартина для параметра наклонаbA для бесспинового случая на случай упругого рассеяния спина 0 на спине 1/2 с сохранением четности. Мы приводим онтимальный ответ для всех энергий, а также более простую гранипу гдеk—импульс в системе центра масс. Здесь индекс Ν относится к абсорбционному вкладу. Мы также получаем ограничения на амплитуду с изменением спиральности

$$cf_{ + - }^A (t)/\sqrt { - t} |_{t = 0} $$

 в терминахσполн,σупр иbA(S).
119107308
Hadron spectra in p+p collisions at RHIC and LHC energies
We present the systematic analysis of transverse momentum (pT) spectra of identified hadrons in p+p collisions at Relativistic Heavy Ion Collider ( and 200 GeV) and at Large Hadron Collider (LHC) energies (, 2.76 and 7.0 TeV) using phenomenological fit functions. We review various forms of Hagedorn and Tsallis distributions and show their equivalence. We use Tsallis distribution which successfully describes the spectra in p+p collisions using two parameters, Tsallis temperature T which governs the soft bulk spectra and power n which determines the initial production in partonic collisions. We obtain these parameters for pions, kaons and protons as a function of center-of-mass energy . It is found that the parameter T has a weak but decreasing trend with increasing . The parameter n decreases with increasing which shows that production of hadrons at higher energies are increasingly dominated by point like qq scatterings. Another important observation is with increasing , the separation between the powers for protons and pions narrows down hinting that the baryons and mesons are governed by same production process as one moves to the highest LHC energy.
118409510
Characteristics of alpha projectile fragments emission in interaction of nuclei with emulsion
The properties of the relativistic alpha fragments produced in interactions of 84Kr at around 1 A GeV in nuclear emulsion are investigated. The experimental results are compared with the similar results obtained from various projectiles with emulsion interactions at different energies. The total, partial nuclear cross-sections and production rates of alpha fragmentation channels in relativistic nucleus-nucleus collisions and their dependence on the mass number and initial energy of the incident projectile nucleus are investigated. The yields of multiple alpha fragments emitted from the interactions of projectile nuclei with the nuclei of light, medium and heavy target groups of emulsion-detector are discussed and they indicate that the projectile-breakup mechanism seems to be free from the target mass number. It is found that the multiplicity distributions of alpha fragments are well described by the Koba-Nielsen-Olesen (KNO) scaling presentation. The mean multiplicities of the freshly produced or newly created charged secondary particles, normally known as shower and secondary particles associated with target in the events where the emission of alpha fragments were accompanied by heavy projectile fragments having Z ≥ 3 seem to be constant as the alpha fragments multiplicity increases, and exhibit a behavior independent of the alpha fragments multiplicity.