We are using five different surveys to compile the largest sample of diffuse interstellar band (DIB) measurements ever collected. GOSSS is obtaining intermediate-resolution blue-violet spectroscopy of ~2500 OB stars, of which 60% have already been observed and processed. The other four surveys have already collected multi-epoch high-resolution optical spectroscopy of 700 OB stars with different telescopes, including the 9 m Hobby-Eberly Telescope in McDonald Observatory. Some of our stars are highly-extinguished targets for which no good-quality optical spectra have ever been published. For all of the targets in our sample we have obtained accurate spectral types, measured non-DIB ISM lines, and compiled information from the literature to calculate the extinction. Here we present the first results of the project, the properties of twenty DIBs in the 4100-5500 Å range. We clearly detect a couple of previously elusive DIBs at 4170 Å and 4591 Å; the latter could have coronene and ovalene cations as carriers.

The Scandium abundances for 85 metal-poor stars are presented. Our result shows that NLTE corrections for Sc II lines are small (−0.04 to +0.06 dex). The abundance trends in stars of different populations are discussed.

We present results of chemical abundance study of a few representative stellar streams of Galactic thick and thin discs. Arcturus stream, which was proposed to have an extragalactic origin, and a recently detected stream called AF06 were studied. Results show a range of metallicity, age and abundance pattern that are consistent with those of Galactic thick disc component. We found similar results for AF06. The abundance and age results unambiguously rule out the possibility that the member stars are vestiges of open clusters. Abundance results of a sample of stars of Sirius and Hercules streams combined with the kinematics show that both the streams belong to the thin disc component. Also, results rule out these are remnants of open clusters. It is likely these streams formed insitu due to perturbations caused by non-axisymmetric components such as bar or spirals.

The diffuse interstellar bands are not due to solid state species. However, under the explicit assumption that DIB carriers survive the transfer from translucent to dark clouds, it is expected that for the low temperatures in the dense interstellar medium also DIB carriers accrete onto dust grains. Like all other molecules, apart from molecular hydrogen, they will get embedded in an ice matrix that largely consists of amorphous solid water. This offers - in principle - a tool to search for DIBs in complete different environments, both in space (i.e., towards embedded young stellar objects) and in the laboratory, namely in the solid state simulating interstellar ice analogues. Currently experiments are ongoing in the Sackler Laboratory for Astrophysics at Leiden Observatory to record optical ice spectra of potential DIB carriers. For this a new experimental approach has been developed. Its performance and potential are discussed.

In its first two observing seasons, the LEGUE (LAMOST Experiment for Galactic Understanding and Exploration; Deng et al., Zhao et al. 2012) survey has obtained ~1.7 million science-quality spectra. We apply corrections to the PPMXL proper motions (PMs; Roeser et al. 2010) as a function of position, as determined from the measured PMs of extragalactic objects discovered in LAMOST spectra (see Fig. 1, left and center panels). LAMOST radial velocities and corrected PMs are used to derive 3D space velocities for ~480,000 F-stars (assuming MV=4 to derive distances). The right panel of Fig. 1 shows the radial component of Galactic cylindrical velocities (VR) for stars between 7.8<RGC<9.8 kpc (with R⊙,GC=7.8 kpc) as a function of height (Z) and angle (θ) from the Galactic X-axis. Each dot represents the average position of stars in a 200x200 pc box, color-coded by the mean VR of those stars. Assuming circularrotation, VR should be zero. This is true on average for θ>0° (3rd Galactic quadrant), but not for θ<0°. The velocities are also asymmetric across the Galactic plane for θ<0° (2nd quadrant), with most positions 〈 VR 〉> 0 above the disk (radially outward), and 〈 VR 〉 < 0 below the disk. Similar structure to this apparent “shearing” motion has been seen in RAVE (e.g., Williams et al. 2013; Siebert et al. 2012), and SDSS (Widrow et al. 2012).

The Strömgren-Crawford (SC) intermediate-band photometric system is a very powerful and efficient one for the detailed study of stars, and therefore the Milky Way and local universe. However, due to the narrow bandwidth, low efficiency of detectors and serious atmospheric extinction in u band, and high photometric accuracy required, there was only one all sky survey in this system finished a decade ago, which is restricted to stars brighter than 8.3 mag in y (equal to V) in the solar neighborhood. In this context, it is the right time to carry out an all sky survey to a completeness depth of ~19 mag, equivalent to a volume-completed distance 4 kpc for solar-type stars. For stars brighter than 15 mag in V, the expected photometric accuracies are ~0.01mag. With these stars, high precision 3D extinction map can be obtained thanks to the β index. Stellar atmospheric parameters can be determined with accuracies comparable to those from high-resolution spectroscopy. Fundamental parameters like stellar luminosities and distances can be reliably estimated as well. We propose to use the Nanshan 1m telescope to start the survey in early 2014 in the Northern sky. There are several 1-m class telescopes in Chile which can be used to perform the Southern sky survey. This entire survey, when finished, will greatly improve our knowledge on stars and the Galaxy, and will provide us the first 6D map of the Milky Way together with the LAMOST survey and the Gaia mission.

We estimate the 3D extinction law in the optical–NIR bands for a line of sight in the 2nd quadrant of the Galactic disk. Two dust lanes are identified at ~9 and ~10.25 kpc in both AV and RV, indicating that the size of the dust grains in the spiral arms is larger than that in the inter-arm regions.

Cationic polycyclic aromatic hydrocarbons (PAHs) are attractive candidates for the Diffuse Interstellar Bands, but to date not a single PAH species has been identified on the basis of a spectral agreement. This indicates either that the molecular diversity is very large or that the candidates that have been considered are not the correct ones. In particular, small/medium-sized PAH cations are submitted to photodissociation under UV photons from stars. Therefore it is of interest to characterize the spectroscopic properties of key breakdown products. Furthermore, these studies should be performed under conditions that mimic those found in interstellar space, which leads to additional experimental difficulties. We describe the approach we are developing with the PIRENEA set-up and present results on the 1-Methylpyrene cation and photo-derived species. Experimental measurements are guided by calculations based on density functional theory.

This closing contribution is structured as a tour of developments of Galactic astronomy over the last forty years, seen from an entirely personal viewpoint. On this background, I try to place some of the current developments in context, with reference to many of the key contributions to this meeting, and speculate where we may be heading in the near future.

The Red Rectangle is a spectacular bipolar nebula centred around the eccentric evolved binary HD 44179. The nebula is rich in spectral signatures: it is the brightest source of the Extended Red Emission (ERE), of the Blue Luminescence (BL) as well as one of the brightest sources of mid-IR PAH bands. Moreover, and unique to this source, a plethora of narrow emission lines is detected on top of the diffuse ERE. Some of these molecular features show rotational contours which become narrower at larger angular separation from the central engine. Some converge to wavelengths and profiles of narrow DIBs. All these observations show that the Red Rectangle is a very rich laboratory to study active astrochemical processes within the nebula. We also address, but fail to answer, the question why this source is so unique among the many observed post-AGB binary analogues.

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 DIBs in the optical and near-infrared wavelength domain, not only in the Galaxy, but also in different environments encountered in Local Group galaxies and beyond. Still, the DIB carriers have remained unidentified. The coming decade will witness the development of extremely large telescopes (GMT, TMT and E-ELT) and their instrumentation. In this overview I will highlight the current instrumentation plan of these future observatories, emphasizing their potential role in solving the enigma of the DIBs.

Using ~2200 BATC main sequence (MS) stars which include SDSS stellar atmospheric parameters, we develop the polynomial photometric calibration method to evaluate the stellar effective temperature and metallicity for BATC data. This calibration method has been applied to about 160 000 MS stars. The mean stellar metallicity smoothly decreases from −0.65 to −0.78 dex in the interval 0.5 < |Z| ≤ 2 kpc. Metallicity distributions in the halo and the thick disk seem invariant with the distance from the Galactic plane.

Up to 10% of the total power output of star-forming galaxies is emitted in the infrared emission features at 3.3, 6.2, 7.7, 8.6 and 11.2 μm. Here, I will review the spectral characteristics of these IR emission bands, their dependence on the local environment, the implications for the physical and chemical characteristics of the carriers, and their applicability as a diagnostic tool.

Since the discovery of the Diffuse Interstellar Bands (DIBs) in the early 1920s, numerous research groups have taken on the task to obtain as complete a census of the DIBs as observationally possible in order to unravel characteristics that would allow the community to tie the DIB carriers to known species. Here, I will briefly review the efforts and progress that were made for the past two decades in producing new, deeper, and more complete DIB surveys. In particular, I will review the important role that these modern surveys are playing in revealing main observational characteristics of the DIBs and their dependence on the local physical conditions in the Galactic Interstellar Medium.

Approximately 80 stars from the thin disk, the thick disk and the halo of the Galaxy, in the range of −3.0 < [Fe/H] < +0.5, surface gravity of 3.0 < logg < 4.7 and temperature of 4500 K < Teff < 6500 K, have been observed with the Shane/Hamilton and CFHT/Espadons spectrographs in order to carry out a systematic NLTE study of nearby stars in a consistent way. We will determine reliably stellar parameters and determine precise elemental abundances via a comprehensive NLTE analysis of the spectral lines of Li, Na, Mg, Al, Si, K, Ca, Sc, Mn, Fe, Sr, Zr, Ba, Nd, and Eu elements. Finally, we aim to investigate the chemical evolution of the Galaxy through different stellar populations based on the NLTE abundances for total 15 elements.

In the early 90's, C60+ was proposed as the carrier of two diffuse interstellar bands (DIBs) at 9577 and 9632 Å, but a firm identification still awaits gas-phase spectroscopic data. Neutral C60, on the other hand, was recently detected through its infrared emission bands in the interstellar medium and evolved stars. In this contribution, we present the detection of C60+ through its infrared vibrational bands in the NGC 7023 nebula, based on spectroscopic observations with the Spitzer space telescope, quantum chemistry calculation, and laboratory data from the literature. This detection supports the idea that C60+ could be a DIB carrier, and provides robust evidence that fullerenes exist in the gas-phase in the interstellar medium. Modeling efforts to design specific observations, combined with new gas-phase data, will be essential to confirm this proposal. A definitive attribution of the 9577 and 9632 Å DIBs to C60+ would represent a significant step forward in the field.

One of the major tasks in interpretation of data from large-scale stellar surveys is to determine the fundamental atmospheric parameters such as effective temperature, surface gravity, and metallicity. In most on-going and upcoming projects, they are derived spectroscopically, relying on classical one-dimensional (1D) model atmospheres and the assumption of LTE. This review discusses the present achievements and problems of non-local thermodynamic equilibrium (NLTE) line-formation calculations for FGK-type stars. The topics that are addressed include (i) the construction of comprehensive model atoms for the chemical elements with complex term system, (ii) possible systematic errors inherent in classical LTE spectroscopic determinations of stellar parameters and chemical abundances, (iii) the uncertainties in final NLTE results caused by the uncertainties in atomic data, and (iv) applications of the NLTE line-formation calculations coupled to the spatial and temporal average 〈3D〉 models to spectroscopic analyses.

We construct axisymmetric mass models for dwarf spheroidal (dSph) galaxies in the Milky Way to obtain realistic limits on the non-spherical structure of their dark halos. This is motivated by the fact that the observed luminous parts of the dSphs are actually non-spherical and cold dark matter models predict non-spherical virialized dark halos on sub-galactic scales. Applying these models to line-of-sight velocity dispersion profiles along three position angles in six Galactic satellites, we find that the best fitting cases for most of the dSphs yield not spherical but oblate and flattened dark halos. We also find that the mass of the dSphs enclosed within inner 300 pc varies depending on their total luminosities, contrary to the conclusion of previous spherical models. This suggests the importance of considering non-spherical shapes of dark halos in dSph mass models.

We present a preliminary analysis of a set of optical (3800-8800 Å) high resolution (R = 80,000) spectra for 69 diffuse interstellar band targets. We carried out a sensitive search for interstellar features in the wavelength range 8470-8740 Å that will be covered by the upcoming GAIA mission. We also investigate how the λ8620Å DIB strength varies as a function of other interstellar parameters (other DIBs, E(B-V) and atomic and molecular column densities).

The dust grains flowing out of the stars are most likely non-spherical and inhomogeneous; viz. porous, fluffy and composites of many very small particles glued together. We calculate the scattering, absorption and extinction efficiencies of such composite grains. The composite grains consist of host silicate spheroid and inclusions of PAHs. We study the extinction as a function of the volume fraction of the inclusions. In particular, we study the variation in the absorption peak, at the wavelength ‘4430Å’ with the volume fraction of the PAH inclusions. We present the composite grain models and discuss the results.