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We present a 24 μ m-selected spectroscopic sample z > 0.13 (median 〈 z 〉 = 0.41) in the Lockman Hole field, consisting of 4035 spectra. Our aim is to identify active galactic nuclei (AGNs) and determine their fraction in this mid-infrared-selected sample. In this work, we use the [Ne v ] λ 3426 emission line to spectroscopically identify AGNs. Combined with broad-line Type I AGNs selected in our previous study, our sample consists of 887 (∼22%) spectroscopically confirmed AGNs. We perform a stacking analysis on the remaining spectra and find that in various mid-infrared (MIR) wedge-selected AGN candidates, the stacked spectra still show significant [Ne v ] λ 3426 emission. In contrast, no clear [Ne v ] λ 3426 signal is detected in non-AGN candidates falling outside the wedges. Assuming a range of AGN MIR spectral energy distribution (SED) slope of −0.3 < α < 0.7, and an average star-forming relation derived from 65 star-forming templates, we develop a robust method to separate the AGN and star-forming contributions to the MIR SEDs using the rest-frame L _12 / L _1.6 versus L _4.5 / L _1.6 diagram. We separate the objects into bins of L _12 and find that the AGN fraction increases with increasing L _12 . We also find that the stacked [Ne v ] λ 3426 strength scales with L _12 . The pure AGN luminosity at 12 μ m exhibits a positive correlation with the star formation rates, indicating possible coevolution and common gas supply between the AGNs and their host galaxies. Varying population properties across the redshift range explored contribute to the observed correlation.

We present a sample of 330 blue edge-on low surface brightness galaxies (ELSBGs). To understand the chemical evolution of ELSBGs, we derived the gas-phase abundance and the [ α /Fe] ratio. Compared with star-forming galaxies, ELSBGs show a flatter trend in the mass–metallicity ( M _* – Z ) relation, which suggests that the oxygen abundance enhancement is inefficient. We focused on 77 ELSBGs with H i data and found that the closed-box model cannot explain their gas fraction and metallicity relation, which implies that infall and/or outflow is needed. We derived the [ α /Fe] ratio of normal ELSBG ( = 10 ^9.5 M _⊙ ) using single stellar population grids from the MILES stellar library. The mean [ α /Fe] ratios are 0.18 and 0.4 for normal ELSBG and massive ELSBG, respectively. We suggest that the long timescales of star formation and/or metal-rich gas outflow events caused by SNe Ia winds are likely to be responsible for the α -enhancement of massive ELSBGs.

We present a sample of 330 blue edge-on low surface brightness galaxies (ELSBGs). To understand the chemical evolution of ELSBGs, we derived the gas-phase abundance and the [ α /Fe] ratio. Compared with star-forming galaxies, ELSBGs show a flatter trend in the mass–metallicity (M *– Z) relation, which suggests that the oxygen abundance enhancement is inefficient. We focused on 77 ELSBGs with H i data and found that the closed-box model cannot explain their gas fraction and metallicity relation, which implies that infall and/or outflow is needed. We derived the [ α /Fe] ratio of normal ELSBG (<109.5 M ⊙) and massive ELSBG (> = 109.5 M ⊙) using single stellar population grids from the MILES stellar library. The mean [ α /Fe] ratios are 0.18 and 0.4 for normal ELSBG and massive ELSBG, respectively. We suggest that the long timescales of star formation and/or metal-rich gas outflow events caused by SNe Ia winds are likely to be responsible for the α -enhancement of massive ELSBGs. [ABSTRACT FROM AUTHOR]

Isoscaling behaviour of the statistical emission fragments from the equilibrated sources with Z = 30 and N = 30, 33, 36 and 39 is investigated in the framework of the isospin-dependent lattice gas model. The dependences of isoscaling parameters a on source isospin asymmetry, temperature and freeze-out density are studied, and the 'symmetry energy' is deduced from isoscaling parameters. The results show that symmetry energy Csym is insensitive to the change of temperature but follows the power-law dependence on the freeze-out density r. The effect of strength of asymmetry of nucleon-nucleon interaction potential on the density dependence of the symmetry energy is discussed. [ABSTRACT FROM AUTHOR]

We investigate the applicability of the independent atom model (IAM) to elastic electron scattering from complex polyatomic molecules, namely C4H10 and C6H6, in the energy range 100-1000 eV. The cross sections of the elastic electron scattering are calculated by employing the IAM together with the relativistic partial waves. The incorporation of both the modified absorption potential and the extended structural factor in the IAM makes the elastic differential cross sections and momentum transfer cross sections have a good agreement with the available experimental data. The present simple model seems to be insensitive to the complexity of the target molecules so that the proposed procedure can be quite useful for calculation of electron scattering from bio-molecules. [ABSTRACT FROM AUTHOR]

Anisotropic flows (v1, v2, v3 and v4) of light fragments up to the mass number 4 as a function of rapidity are studied for 25 MeV/nucleon 40Ca + 40Ca at large impact parameters by a quantum molecular dynamics model. A phenomenological scaling behaviour of rapidity dependent flow parameters vn (n = 1, 2, 3 and 4) is found as a function of mass number plus a constant term, which may arise from the interplay of collective and random motions. In addition, v4/v22 keeps to be almost independent of rapidity and remains a rough constant of 1/2 for all light fragments. [ABSTRACT FROM AUTHOR]

We investigate the differential cross sections (DCS) of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100-700 eV by employing the independent atom model (IAM) together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron-molecule scattering. [ABSTRACT FROM AUTHOR]

Elliptic flow (v2) and hexadecupole flow (v4) of light clusters have been studied in detail for 25 MeV/nucleon 86Kr + 124Sn at large impact parameters by using a quantum molecular dynamics model with different potential parameters. Four sets of parameters including soft or hard equation of state (EOS) with or without symmetry energy term are used. Both number-of-nucleon (A) scaling of the elliptic flow versus transverse momentum (pt) and the scaling of v4/A2 versus (pt/A)2 have been demonstrated for the light clusters in all above calculation conditions. It is also found that the ratio of v4/v22 maintains a constant of ½ which is independent of pt for all the light fragments. Comparisons among different combinations of the EOS and the symmetry potential term show that the above scaling behaviours are sound and independent of the details of potential, while the strengths of flows are sensitive to the EOS and the symmetry potential term. [ABSTRACT FROM AUTHOR]

A sequential decay model is used to study isoscaling, i.e. the factorization of the isotope ratios from sources of different isospins and sizes over a broad range of excitation energies, into fugacity terms of proton and neutron number, R21(N,Z) = Y2(N,Z)/Y1(N,Z) = Ce(?N+?Z). It is found that the isoscaling parameters ?and ?have a strong dependence on the isospin difference of equilibrated source and excitation energy, no significant influence of the source size on ?and ?has been observed. It is found that ?and ?decrease with the excitation energy and are linear functions of 1/Tand ?(Z/A)2or ?(N/A)2of the sources. Symmetry energy coefficient Csymis constrained from the relationship of ?and source ?(Z/A)2, ?and source ?(N/A)2. [ABSTRACT FROM AUTHOR]

We demonstrate a diode-pumped passively cw mode-locked Nd:CaGdAlO4 laser operating at 1079nm with a semiconductor saturable absorber mirror for the first time to the best of our knowledge. The threshold pump power of the laser is 180mW. A maximum average output power of 93mW is obtained under the pump power of 1.94 W. The pulse duration of the mode-locked pulses is 3.1 ps and the repetition rate is 157 MHz. [ABSTRACT FROM AUTHOR]

A diode pumped Kerr-lens mode-locked femtosecond Yb:LSO laser is experimentally demonstrated for the first time. The 54 fs laser pulses at central wavelength of 1052 nm with a bandwidth of 22.5 nm are obtained at the repetition rate of 113 MHz. To the best of our knowledge, this is the shortest pulse duration ever produced from the Yb-doped orthosilicates lasers family. [ABSTRACT FROM AUTHOR]

A diode-pumped passively mode-locked Nd-doped La3Ga5SiO14 (Nd:LGS) laser is realized by using a semiconductor saturable absorber mirror. With the pump power of 2 W, we obtain a 532 nm self-frequency doubling (SFD) laser together with a 10.9 ps fundamental laser at the repetition rate of 173.7 MHz. To the best of our knowledge, it is the first time for self-frequency doubling in the diode-pumped mode-locked Nd:LGS laser. Benefited from the diode lasers and its self-frequency doubling property, Nd:LGS could be a potential candidate for compact, stable and cheap ultrafast green laser sources. [ABSTRACT FROM AUTHOR]

Effects of neutron skin thickness in peripheral nuclear collisions are investigated using the statistical abrasion ablation (SAA) model. The reaction cross section, neutron (proton) removal cross section, one-neutron (proton) removal cross section as well as their ratios for nuclei with different neutron skin thickness are studied. It is demonstrated that there are good linear correlations between these observables and the neutron skin thickness for neutron-rich nuclei. The ratio between the (one-)neutron and proton removal cross section is found to be the most sensitive observable of neutron skin thickness. Analysis shows that the relative increase of this ratio could be used to determine the neutron skin size in neutron-rich nuclei. [ABSTRACT FROM AUTHOR]

Different phenomena are observed under negative gate voltage stress which is smaller than the previous degradation stress in PMOSFETs with different oxide thicknesses. We adopt the real time method to make a point of the drain current to study the degradation and recovery of negative bias temperature instability (NBTI). For the device with thin oxide, recovery phenomenon appears when smaller negative voltage stress was applied, due to the more influencing oxide charges detrapping effects than the interface states. For the device with thick oxide, not recovery but degradation phenomenon comes forth. As many charges are trapped in the deeper position and higher energy level in the oxide, these charges can not be detrapped. Therefore, the effect of the charge detrapping is smaller than that of the interface states in the thick oxide. The degradation presents itself during the 'recovery' time. [ABSTRACT FROM AUTHOR]