An inspection of the DSS and 2MASS images of selected Milky Way regions has led to the discovery of 66 stellar groupings whose morphologies, color-magnitude diagrams, and stellar density distributions suggest that these objects are possible open clusters that do not yet appear to be listed in any catalogue. For 24 of these groupings, which we consider to be the most likely to be candidates, we provide extensive descriptions on the basis of 2MASS photometry and their visual impression on DSS and 2MASS. Of these cluster candidates, 9 have fundamental parameters determined by fitting the color-magnitude diagrams with solar metallicity Padova isochrones. An additional 10 cluster candidates have distance moduli and reddenings derived from K magnitudes and (J − K) color indices of helium-burning red clump stars. As an addendum, we also provide a list of a number of apparently unknown galactic and extragalactic objects that were also discovered during the survey.

Abstract:Recent Hα surveys such as SHS and IPHAS have improved the completeness of the Galactic planetary nebula (PN) census. We now know of ∼3000 PNe in the Galaxy, but this is far short of most estimates, typically ∼25 000 or more for the total population. The size of the Galactic PN population is required to derive an accurate estimate of the chemical enrichment rates of nitrogen, carbon, and helium. In addition, a high PN count (>20 000) is strong evidence that most main-sequence stars of mass 1-8 M will go through a PN phase, while a low count (<10 000) argues that special conditions (e.g. close binary interactions) are required to form a PN. We describe a technique for finding hundreds more PNe using the existing data collections of the digital sky surveys, thereby improving the census of Galactic PNe.

Context. The Galactic globular cluster system is incompletely known, especially in the low-latitude regions of the Galactic bulge and disk. We report the physical characterisation of 12 star clusters in the Milky Way, most of which are explored here for the first time. Aims. Our primary aim is determining their main physical parameters, such as reddening, extinction, metallicity, age, total luminosity, mean cluster proper motions (PMs), and distances, in order to reveal the physical nature of these clusters. Methods. We study the clusters using optical and near-infrared (NIR) datasets. In particular, we use the Gaia Early Data Release 3 (EDR3) PMs in order to perform a PM decontamination procedure and build final catalogues with probable members. We match the Gaia EDR3 with the VISTA Variables in the Vía Láctea extended (VVVX) survey and the Two Micron All-Sky survey (2MASS) in the NIR, in order to construct complete NIR and optical colour-magnitude diagrams (CMDs) and investigate the clusters properties. Results. The extinctions are evaluated using existing reddening maps. We find ranges spanning 0.09 ≲ AKs ≲ 0.86 mag and 0.89 ≲ AG ≲ 4.72 mag in the NIR and optical, respectively. Adopting standard intrinsic red clump (RC) magnitudes and extinction values, we first obtain the distance modulus for each cluster and thereafter their heliocentric distances, which range from about 4 to 20 kpc. Therefore, we are able to place these clusters at 3 ≲ RG ≲ 14 kpc from the Galactic centre. The best PARSEC isochrone fit yields a metallicity range of −1.8 < [Fe/H] < +0.3 and an approximate age range of 2 < age < 14 Gyr. Finally, we find that all clusters have low luminosities, with −6.9 < MV < −3.5 mag. Conclusions. Based on our photometric analysis, we find both open clusters (OCs) and globular clusters (GCs) in our sample. In particular, we confirm the OC nature for Kronberger 100, while we classify Patchick 125 as a metal-poor GC, Ferrero 54 as a metal-rich GC, and ESO 92-18 as a possible old OC or young GC. The classification as GC candidates is also suggested for Kronberger 99, Patchick 122, Patchick 126, Riddle 15, FSR 190, and Gaia 2. We also conclude that Kronberger 119 and Kronberger 143 might be either old OCs or young GCs.

On the applicability of Sato's equation to capacitative radiofrequency sheaths J Balakrishnan and G R Nagabhushana -Investigation of Al x Ga 1-x As injection heterolasers emittingvisible radiation R Altynbaev, L M Dolginov, L V Druzhinina et al. -The invariance of DSHs and DVHs under bladder filling changes

Abstract.Having surveyed ≈ 10% of the sky, we have identified more than 130 PN candidates by surveying multicolour Digitized Sky Survey (DSS), Sloan Digitized Sky Survey (SDSS), and combined [O III], Hα and [S II] images. In a first imaging and spectroscopy campaign, 51 objects were identified as true and probable PNe. This work presents an additional 17 probable or possible PNe identified since that study. The majority of these candidates are situated at Galactic latitudes |b| > 5• , with the exception of seven objects located closer to the Galactic plane. Using the techniques described here that do not require any new survey data, we anticipate that many more PNe are waiting to be found, perhaps as many as 90.