Related papers: The CNO problem in magnetic cataclysmic variables
We calculate theoretical population ratios of the ground fine-structure levels of some atoms/ions which typically exhibit UV lines in the spectra of QSO absorbers redward the Ly-alpha forest: C0, C+, O0, Si+ and Fe+. The most reliable…
[Abridged] The [OIII]$_{88\mu m}$/[CII]$_{158\mu m}$ and [OIII]$_{88\mu m}$/[NII]$_{122\mu m}$ luminosity ratios have shown to be promising tracers of the ionisation state and gas-phase metallicity of the ISM. Observations of galaxies at…
Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…
Recent DESI results indicate a strong preference for dynamical dark energy (DE) when baryon acoustic oscillation (BAO) measurements are combined with supernovae (SNe) and cosmic microwave background (CMB) data using the…
We present the study of CI/H$_2$ relative abundance in the diffuse cold neutral medium. Using the chemical and thermal balance model we calculated the dependence of CI/H$_2$ on the main parameters of the medium: hydrogen number density,…
Non-Maxwellian $\kappa$ electron energy distributions (EEDs) have been proposed in recent years to resolve the so-called ``electron temperature and abundance discrepancy problem'' in the study of planetary nebulae (PNe). Thus the need to…
The interior structure of the Sun can be studied with great accuracy using observations of its oscillations, similar to seismology of the Earth. Precise agreement between helioseismological measurements and predictions of theoretical solar…
Aims: We test predictions of evolution models on mixing of CNO-cycled products in massive stars from a fundamental perspective. Relative changes within the theoretical C:N:O abundance ratios and the buildup of helium are compared with…
The possibility of unaccounted for opacity sources in the UV for late-type stars has often been invoked to explain discrepancies between predicted and observed flux distributions and spectral line strengths. Such missing UV-opacity could…
We present robust, model-marginalized limits on both the total neutrino mass ($\sum m_\nu$) and abundance ($N_{\rm eff}$) to minimize the role of parameterizations, priors and models when extracting neutrino properties from cosmology. The…
We report a charge based model to establish the analytical equation, describing the nature of capacitance-voltage ($C$-$V$) characteristics of organic solar cells under dark condition (or organic diodes) over a wide range of voltage,…
Recently revealed C, N, and O abundances in the most metal-poor damped Lyman-alpha (DLA) absorbers are compared with those of extremely metal-poor stars in the Galactic halo, as well as extragalactic H II regions, to decipher…
We present an analysis of 436 lines of sight with extinction data covering wavelength range from near-infrared (NIR) to ultraviolet (UV). We use J, H, K photometry from 2MASS database, the IR intrinsic colors from Wegner (1994), and UV…
We present here a method to estimate physical parameters of novae systems using an extensive grid of photoionization models for novae. We use the photoionization code CLOUDY to construct grid of models covering a wide range of different…
We identified a possible origin of the difficulty in abundance analysis of cool luminous stars. We found purely empirically that there is a limit of logW/nu = -4.75 (W: equivalent width, nu: wavenumber) above which the observed lines do not…
We used newly obtained observations from the Mid-Infrared Instrument (MIRI) equipped with the Medium Resolution Spectrometer (MRS) aboard the James Webb Space Telescope (JWST) to extract spectra covering the entire spectral range from 5 to…
We present synthetic line observations of a simulated molecular cloud, utilising a self-consistent treatment of the dynamics and time-dependent chemical evolution. We investigate line emission from the three most common CO isotopologues…
The metallicity evolution and ionization history of the universe must leave its imprint on the Cosmic Microwave Background through resonant scattering of CMB photons by atoms, ions and molecules. These transitions partially erase original…
Deep Keck spectropolarimetry has been obtained of a sample of powerful radio galaxies with $z \sim 2.5 \pm 1$. In addition to a clear 2200\AA dust scattering/extinction signature and an inverse correlation between the degree of continuum…
Line intensity mapping (LIM) is a rapidly emerging technique for constraining cosmology and galaxy formation using multi-frequency, low angular resolution maps. Many LIM applications crucially rely on cross-correlations of two line…