Related papers: Linear/circular spectropolarimetry of diffuse inte…
The rest wavelengths of DIBs are of fundamental importance owing to the lack of unambiguous identification for these mysterious features. Usually the wavelengths of DIBs are estimated using known interstellar lines serving to shift the…
Diffuse interstellar bands (DIBs) are broad absorption features associated with interstellar dust and can serve as chemical and kinematic tracers. Conventional measurements of DIBs in stellar spectra are complicated by residuals between…
The identification of the carrier(s) of diffuse interstellar bands (DIBs) is one of the oldest mysteries in stellar spectroscopy. With the advent of 8-10m-class telescopes substantial progress has been made in measuring the properties of…
The near-star environment around obscured stars is very dynamic. Many classes of stars show evidence for winds, disks, inflows and outflows with many phenomena occurring simultaneously. These processes are involved in stellar evolution,…
We present the results of an optical absorption study of NGC 7293, the Helix planetary nebula (PN), designed to search for diffuse band (DIB) absorptions perhaps arising in the carbon-rich circumstellar matter of the PN. We made high…
The gas-phase optical absorption spectrum of a thiophenoxy radical (C6H5S), a diffuse interstellar band (DIB) candidate molecule, was observed in the discharge of thiophenol using a cavity ringdown spectrometer. The ground-state rotational…
Up to now, no laboratory-based study has investigated polycyclic aromatic hydrocarbon (PAH) species as potential carriers of both the diffuse interstellar bands (DIBs) and the 2175 A UV bump. We examined the proposed correlation between…
The carriers of diffuse interstellar bands are still mysterious species. There exist many arguments that diffuse bands at 5797 and 5850 angstroms have the same carrier. Using high-resolution spectra of few dozens of reddened stars we have…
The carbonaceous macromolecules imprinting in astronomical spectra the numerous absorptions called Diffuse Interstellar Bands (DIBs) are omnipresent in the Galaxy and beyond and represent a considerable reservoir of organic matter. However,…
We present a model for the diffuse interstellar dust that explains the observed wavelength-dependence of extinction, emission, linear and circular polarisation of light. The model is set-up with a small number of parameters. It consists of…
We obtained the near-infrared (NIR) high-resolution ($R\equiv\lambda/\Delta\lambda\sim20,000$) spectra of the seven brightest early-type stars in the Cygnus OB2 association for investigating the environmental dependence of diffuse…
Potential vibrational modes associated with diffuse interstellar bands (DIBs) could be discerned by examining energy differences between correlated DIBs. Consequently, $\approx 10^3$ higher correlated DIB pairs ($r-\sigma_r \ge 0.8$, $\ge…
Astronomical near-infrared Diffuse-Interstellar-Bands (DIBs) were characterized by pure carbon Fullerene and Graphene molecules comparing with laboratory experiment and with Time-Dependent Density-Functional-Theory (TD-DFT) analysis. It is…
Studying the composition of dust in the interstellar medium (ISM) is crucial in understanding the cycle of dust in our galaxy. The mid-infrared spectral signature of amorphous silicates, the most abundant dust species in the ISM, is studied…
The diffuse interstellar band (DIB) at 6196 A exhibits notable profile variations across the Milky Way. This study addresses three open issues: the unusual broadening of the DIB profile towards Upper Sco (USco), the lack of profile…
Young giant planets and brown dwarf companions emit near-infrared radiation that can be linearly polarized up to several percent. This polarization can reveal the presence of a circumsubstellar accretion disk, rotation-induced oblateness of…
The first gas-phase infrared spectra of two isolated astronomically relevant and large PAH cations - diindenoperylene (DIP) and dicoronylene (DC) - in the 530$-$1800 cm$^{-1}$ (18.9$-$5.6 $\mu$m) range - are presented. Vibrational band…
The dielectric function of interstellar dust material is modeled using observations of extinction and polarization in the infrared, together with estimates for the mass of interstellar dust. The "astrodust" material is assumed to be a mix…
This paper considers a very special set of a few interstellar features --- broad diffuse interstellar bands (DIBs) at 4430, 4882, 5450, 5779 and 6175 \AA\AA. The set is small, and measurements of equivalent widths of these DIBs are…
We present the largest sample to-date of intermediate-resolution blue-to-red optical spectra of B-type supergiants in M31 and undertake the first survey of diffuse interstellar bands (DIBs) in this galaxy. Spectral classifications, radial…