We study the effect of corotation resonance on the inertial-acoustic oscillations (pmodes) of black-hole accretion discs. Previous works have shown that for barotropic flows (where the pressure depends only on the density), wave absorption at the corotation resonance can lead to mode growth when the disc vortensity, ζ = κ/(2ΩΣ) (where Ω, κ, Σ are the rotation rate, radial epicyclic frequency an...

Using the stellar population synthesis, we model the stellar contribution for a sample of 110 doublepeaked broad-lines AGNs from the Sloan Digital Sky Survey (SDSS). The stellar velocity dispersions (σ∗) are obtained for 52 double-peaked AGNs with obvious stellar absorption features, ranging from 106 to 284 km s . We also use multi-component profiles to fit [O III]λλ4959, 5007 and Hβ emission l...

The structural parameters, elastic constants and electronic structure of NbB(2) under pressure are investigated by using first-principles plane-wave pseudopotential density functional theory within the generalized gradient approximation (GGA). The obtained results are in agreement with the available theoretical data. It is found that the elastic constants and the Debye temperature of NbB(2) inc...

We show that the Wyman’s solution may be obtained from the fourdimensional Einstein’s equations for a spherically symmetric, minimally coupled, massless scalar field by using the continuous self-similarity of those equations. The Wyman’s solution depends on two parameters, the mass M and the scalar charge Σ. If one fixes M to a positive value, say M0, and let Σ 2 take values along the real line...

Type 2 active galactic nuclei (AGN) represent the majority of the AGN population. However, due to the difficulties in measuring their black hole (BH) masses, it is still unknown whether they follow the same BH mass-host galaxy scaling relations valid for quiescent galaxies and type 1 AGN. Here we present the locus of type 2 AGN having virial BH mass estimates in the MBH − σ⋆ plane. Our analysis...

The second moment of the Hβ emission line is calculated for 329 narrow line Seyfert 1 galaxies (NLS1s) selected from the Sloan Digital Sky Survey (SDSS), which is used to calculate the central supermassive black hole (SMBHs) mass of each. We find that the second moment depends strongly on the broader component of the Hβ line profile. We find that for the NLS1s requiring two Gaussians to fit the...

We present Keck LRIS spectroscopy of the black hole-hosting globular cluster RZ2109 in the Virgo elliptical galaxy NGC 4472. We find that this object has extraordinarily broad [O III]λ5007 and [O III]λ4959 emission lines, with velocity widths of approximately 2,000kms. This result has significant implications for the nature of this accreting black-hole system and the mass of the globular cluste...

The observed properties of supermassive black holes suggest a fundamental link between their assembly and the formation of their host spheroids. We model the growth and activity of black holes in galaxies using ΛCDM cosmological hydrodynamic simulations by following the evolution of the baryonic mass component in galaxy potential wells. We find that the observed steep relation between black hol...

Type I and II halogen bonds are well-recognized motifs that commonly occur within crystals. Quantum calculations applied to examine whether such geometries might in their closely related chalcogen bond cousins. Homodimers constructed of the R1R2C=Y R1R2Y monomers, wherein Y represents a atom, S, Se, or Te; R1 R2 refer either H F. A (T2) geometry lone pair one is aligned with σ-hole its partner ...

We report upper limits on the masses of black holes that can be present in the centers of sixteen nearby galaxy bulges. These limits Mlim BH for our statistically complete sample were derived from the modeling of the central emission-line widths ([N II] or [S II]), observed over a 0.′′25× 0.2 (R <∼ 9 pc) aperture. The experiment has a mean detection sensitivity of ∼ 3.9×106 M⊙. For three sample...