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We report the detection of GJ 3090 b (TOI-177.01), a mini-Neptune on a 2.9-day orbit transiting a bright (K = 7.3 mag) M2 dwarf located at 22 pc. The planet was identified by the Transiting Exoplanet Survey Satellite and was confirmed with the High Accuracy Radial velocity Planet Searcher radial velocities. Seeing-limited photometry and speckle imaging rule out nearby eclipsing binaries. Additional transits were observed with the LCOGT, Spitzer, and ExTrA telescopes. We characterise the star to have a mass of 0.519 $\pm$ 0.013 M$_\odot$ and a radius of 0.516 $\pm$ 0.016 R$_\odot$. We modelled the transit light curves and radial velocity measurements and obtained a planetary mass of 3.34 $\pm$ 0.72 M$_\oplus$, a radius of 2.13 $\pm$ 0.11 R$_\oplus$, and a mean density of 1.89$^{+0.52}_{-0.45}$ g/cm$^3$. The low density of the planet implies the presence of volatiles, and its radius and insolation place it immediately above the radius valley at the lower end of the mini-Neptune cluster. A coupled atmospheric and dynamical evolution analysis of the planet is inconsistent with a pure H-He atmosphere and favours a heavy mean molecular weight atmosphere. The transmission spectroscopy metric of 221$^{+66}_{-46}$ means that GJ 3090 b is the second or third most favourable mini-Neptune after GJ 1214 b whose atmosphere may be characterised. At almost half the mass of GJ 1214 b, GJ 3090 b is an excellent probe of the edge of the transition between super-Earths and mini-Neptunes. We identify an additional signal in the radial velocity data that we attribute to a planet candidate with an orbital period of 13 days and a mass of 17.1$^{+8.9}_{-3.2}$ M$_\oplus$, whose transits are not detected., Comment: 25 pages, 26 figures, accepted for publication in A&A

The Transiting Exoplanet Survey Satellite (\textit{TESS}) mission was designed to perform an all-sky search of planets around bright and nearby stars. Here we report the discovery of two sub-Neptunes orbiting around the TOI 1062 (TIC 299799658), a V=10.25 G9V star observed in the TESS Sectors 1, 13, 27 & 28. We use precise radial velocity observations from HARPS to confirm and characterize these two planets. TOI 1062b has a radius of 2.265^{+0.095}_{-0.091} Re, a mass of 11.8 +\- 1.4 Me, and an orbital period of 4.115050 +/- 0.000007 days. The second planet is not transiting, has a minimum mass of 7.4 +/- 1.6 Me and is near the 2:1 mean motion resonance with the innermost planet with an orbital period of 8.13^{+0.02}_{-0.01} days. We performed a dynamical analysis to explore the proximity of the system to this resonance, and to attempt at further constraining the orbital parameters. The transiting planet has a mean density of 5.58^{+1.00}_{-0.89} g cm^-3 and an analysis of its internal structure reveals that it is expected to have a small volatile envelope accounting for 0.35% of the mass at maximum. The star's brightness and the proximity of the inner planet to the "radius gap" make it an interesting candidate for transmission spectroscopy, which could further constrain the composition and internal structure of TOI 1062b., Comment: 14 pages, 11 figures

Pan-STARRS1 has carried out a set of distinct synoptic imaging sky surveys including the $3\pi$ Steradian Survey and the Medium Deep Survey in 5 bands ($grizy_{P1}$). The mean 5$\sigma$ point source limiting sensitivities in the stacked 3$\pi$ Steradian Survey in $grizy_{P1}$ are (23.3, 23.2, 23.1, 22.3, 21.4) respectively. The upper bound on the systematic uncertainty in the photometric calibration across the sky is 7-12 millimag depending on the bandpass. The systematic uncertainty of the astrometric calibration using the Gaia frame comes from a comparison of the results with Gaia: the standard deviation of the mean and median residuals ($ \Delta ra, \Delta dec $) are (2.3, 1.7) milliarcsec, and (3.1, 4.8) milliarcsec respectively. The Pan-STARRS system and the design of the PS1 surveys are described and an overview of the resulting image and catalog data products and their basic characteristics are described together with a summary of important results. The images, reduced data products, and derived data products from the Pan-STARRS1 surveys are available to the community from the Mikulski Archive for Space Telescopes (MAST) at STScI., Comment: 38 pages, 29 figures, 12 tables

This paper describes the organization of the database and the catalog data products from the Pan-STARRS1 $3\pi$ Steradian Survey. The catalog data products are available in the form of an SQL-based relational database from MAST, the Mikulski Archive for Space Telescopes at STScI. The database is described in detail, including the construction of the database, the provenance of the data, the schema, and how the database tables are related. Examples of queries for a range of science goals are included. The catalog data products are available in the form of an SQL-based relational database from MAST, the Mikulski Archive for Space Telescopes at STScI., Comment: 63 pages, 59 tables, 16 figures

We selected and studied 180 pairs with dV < 800 km/s and Dp < 60 kpc containing Markarian (MRK) galaxies to investigate the dependence of galaxies' integral parameters, star-formation (SF) and active galactic nuclei (AGN) properties on kinematics of pairs, their structure and large-scale environments. Projected radial separation Dp and perturbation level P are better measures of interaction strength than dV. The latter correlates with the density of large-scale environment and with the morphologies of galaxies. Both galaxies in a pair are of the same nature, the only difference is that MRK galaxies are usually righter than their neighbors. Specific star formation rates (SSFR) of galaxies in pairs with smaller Dp or dV is in average 0.5 dex higher than that of galaxies in pairs with larger Dp or dV. Closeness of a neighbor with the same and later morphological type increases the SSFR, while earlier-type neighbors do not increase SSFR. Major interactions/mergers trigger SF and AGN more effectively than minor ones. The fraction of AGNs is higher in more perturbed pairs and pairs with smaller Dp. AGNs typically are in stronger interacting systems than star-forming and passive galaxies. There are correlations of both SSFRs and spectral properties of nuclei between pair members., Comment: 4 pages, 3 figures. arXiv admin note: substantial text overlap with arXiv:1310.0241

According to the database from the first paper, we select 180 pairs with dV < 800 km/s and Dp < 60 kpc containing Markarian (MRK) galaxies. We study the dependence of galaxies integral parameters, star-formation (SF) and active galactic nuclei (AGN) properties on kinematics of pairs, their structure and large-scale environments. Following main results were obtained: projected radial separation Dp between galaxies correlates with the perturbation level P of the pairs. Both parameters do not correlate with line-of-sight velocity difference dV of galaxies. Dp and P are better measures of interaction strength than dV. The latter correlates with the density of large-scale environment and with the morphologies of galaxies. Both galaxies in a pair are of the same nature, the only difference is that MRK galaxies are usually brighter than their neighbors in average by 0.9 mag. Specific star formation rates (SSFR) of galaxies in pairs with smaller Dp or dV is in average 0.5 dex higher than that of galaxies in pairs with larger Dp or dV. Closeness of a neighbor with the same and later morphological type increases the SSFR, while earlier-type neighbors do not increase SSFR. Major interactions/mergers trigger SF and AGN more effectively than minor ones. The fraction of AGNs is higher in more perturbed pairs and pairs with smaller Dp. AGNs typically are in stronger interacting systems than star-forming and passive galaxies. There are correlations of both SSFRs and spectral properties of nuclei between pair members., Comment: 13 pages, 8 figures, 2 tables

The catalogue of close neighbors of Markarian galaxies located inside of circles with radii 60 kpc from the centers of Markarian objects is presented, which combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the Digitized Sky Survey (DSS) Jpg (blue), Fpg (red) and Ipg (near-infrared) band photographic plates. We provide names, accurate coordinates, redshifts, morphological types, blue, red and near-infrared apparent magnitudes, apparent blue major diameters, axial ratios, as well as position angles for the neighbor galaxies. We also include their 2MASS infrared magnitudes. The total number of Markarian galaxies in the database is 274 and number of their neighbors is 359. The physical parameters of the systems of Markarian galaxies and their neighbors are determined and presented., Comment: 17 pages, 1 figure, 1 table, published in Astrophysics (English translation of Astrofizika)

Based on the database of 56 supernovae (SNe) events discovered in 3838 galaxies of the southern hemisphere, we compute the rate of SNe of different types along the Hubble sequence normalized to the optical and near-infrared (NIR) luminosities as well as to the stellar mass of the galaxies. We find that the rates of Type Ia SNe show a dependence on both morphology and colors of the galaxies, and therefore, on the star-formation activity. The rate of SNe Ia can be explained by assuming that at least 15% of Ia events in spiral galaxies originate in relatively young stellar populations. We also find that the rates show no modulation with nuclear activity or environment., Comment: 2 pages

Based on the database compiled in the first article of this series, with 56 SN events discovered in 3838 galaxies of the southern hemisphere, we compute the rate of supernovae (SNe) of different types along the Hubble sequence normalized to the optical and near-infrared luminosities as well as to the stellar mass of the galaxies. We find that the rates of all SN types show a dependence on both morphology and colors of the galaxies, and therefore, on the star-formation activity. The rate of core-collapse (CC) SNe is confirmed to be closely related to the Star Formation Rate (SFR) and only indirectly to the total mass of the galaxies. The rate of SNe Ia can be explained by assuming that at least 15% of Ia events in spiral galaxies originates in relatively young stellar populations. We find that the rates show no modulation with nuclear activity or environment. The ratio of SN rates between types Ib/c and II shows no trend with spiral type., Comment: 13 pages, 2 figures, 5 tables, published in Astrophysics (English translation of Astrofizika)

A database for the entire catalog of the Second Byurakan Survey (SBS) galaxies is presented. It contains new measurements of their optical parameters and additional information taken from the literature and other databases. The measurements were made using Ipg(near-infrared), Fpg(red) and Jpg(blue) band images from photographic sky survey plates obtained by the Palomar Schmidt telescope and extracted from the STScI Digital Sky Survey (DSS). The database provides accurate coordinates, morphological type, spectral and activity classes, apparent magnitudes and diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50 kpc. The total number of individual SBS objects in the database is now 1676. The 188 Markarian galaxies which were re-discovered by SBS are not included in this database. We also include redshifts that are now available for 1576 SBS objects, as well as 2MASS infrared magnitudes for 1117 SBS galaxies., Comment: 13 pages, 1 figure, 1 table

The entire Kazarian galaxies (KG) catalog is presented which combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the STScI Digitized Sky Survey (DSS) of Jpg(blue), Fpg(red) and Ipg(NIR) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. We provide accurate coordinates, morphological type, spectral and activity classes, blue apparent diameters, axial ratios, position angles, red, blue and NIR apparent magnitudes, as well as counts of neighboring objects in a circle of radius 50 kpc from centers of KG. Special attention was paid to the individual descriptions of the galaxies in the original Kazarian lists, which clarified many cases of misidentifications of the objects, particularly among interacting systems. The total number of individual Kazarian objects in the database is now 706. We also include the redshifts which are now available for 404 galaxies and the 2MASS infrared magnitudes for 598 KG. The database also includes extensive notes, which summarize information about the membership of KG in different systems of galaxies, and about revised activity classes and redshifts. An atlas of several interesting subclasses of KG is also presented., Comment: 15 pages, 5 figures, 1 table, Accepted in Astrophysics, Vol. 53, No. 1, 2010 (English translation of Astrofizika)

The determination of the supernova (SN) rate is based not only on the number of detected events, but also on the properties of the parent galaxy population. This is the first paper of a series aimed at obtaining new, refined, SN rates from a set of five SN surveys, by making use of a joint analysis of near-infrared (NIR) data. We describe the properties of the 3838 galaxies that were monitored for SNe events, including newly determined morphologies and their DENIS and POSS-II/UKST I, 2MASS and DENIS J and Ks and 2MASS H magnitudes. We have compared 2MASS, DENIS and POSS-II/UKST IJK magnitudes in order to find possible systematic photometric shifts in the measurements. The DENIS and POSS-II/UKST I band magnitudes show large discrepancies (mean absolute difference of 0.4 mag), mostly due to different spectral responses of the two instruments, with an important contribution (0.33 mag rms) from the large uncertainties in the photometric calibration of the POSS-II and UKST photographic plates. In the other wavebands, the limiting near infrared magnitude, morphology and inclination of the galaxies are the most influential factors which affect the determination of photometry of the galaxies. Nevertheless, no significant systematic differences have been found between of any pair of NIR magnitude measurements, except for a few percent of galaxies showing large discrepancies. This allows us to combine DENIS and 2MASS data for the J and Ks filters., Comment: 17 pages, 3 figures, 5 tables, published in Astrophysics, Vol. 52, No. 1, 2009 (English translation of Astrofizika)

The GSC-II is an all-sky database of objects derived from the uncompressed DSS that the STScI has created from the Palomar and UK Schmidt survey plates and made available to the community. Like its predecessor (GSC-I), the GSC-II was primarily created to provide guide star information and observation planning support for HST. This version, however, is already employed at some of the ground-based new-technology telescopes such as GEMINI, VLT, and TNG, and will also be used to provide support for the JWST and Gaia space missions as well as LAMOST, one of the major ongoing scientific projects in China. Two catalogs have already been extracted from the GSC-II database and released to the astronomical community. A magnitude-limited (R=18.0) version, GSC2.2, was distributed soon after its production in 2001, while the GSC2.3 release has been available for general access since 2007. The GSC2.3 catalog described in this paper contains astrometry, photometry, and classification for 945,592,683 objects down to the magnitude limit of the plates. Positions are tied to the ICRS; for stellar sources, the all-sky average absolute error per coordinate ranges from 0.2" to 0.28" depending on magnitude. When dealing with extended objects, astrometric errors are 20% worse in the case of galaxies and approximately a factor of 2 worse for blended images. Stellar photometry is determined to 0.13-0.22 mag as a function of magnitude and photographic passbands (B,R,I). Outside of the galactic plane, stellar classification is reliable to at least 90% confidence for magnitudes brighter than R=19.5, and the catalog is complete to R=20., Comment: 52 pages, 33 figures, to be published in AJ August 2008

It is widely accepted that the progenitors of core collapse SNe are young massive stars and therefore their host galaxies are mostly spiral or irregular galaxies dominated by a young stellar population. Surprisingly, among morphologically classified hosts of core collapse SNe, we find 22 cases where the host has been classified as an Elliptical or S0 galaxy. To clarify this apparent contradiction, we carry out a detailed morphological study and an extensive literature search for additional information on the sample objects. Our results are as follows: 1. Of 22 "early type" objects, 17 are in fact misclassified spiral galaxies, one is a misclassified irregular, and one is a misclassified ring galaxy. 2. Of the 3 objects maintaining the early type classification, one (NGC2768) is a suspected merger remnant, another (NGC4589) is definitely a merger, and the third (NGC2274) is in close interaction. The presence of some amount of young stellar population in these galaxies is therefore not unexpected. These results confirm the presence of a limited, but significant, number of core collapse SNe in galaxies generally classified of early type. In all cases, anyway, there are independent indicators of the presence in host galaxies of recent star formation due to merging or gravitational interaction., Comment: 12 pages, 1 figure, 1 table, accepted for publication in A&A

The GSC-II white dwarf survey was designed to identify faint and high proper motion objects, which we used to define a new and independent sample of cool white dwarfs. With this survey we aim to derive new constraints on the halo white dwarf space density. Also, these data can provide information on the age of thick disk and halo through the analysis of the luminosity function. On the basis of astrometric and photometric parameters, we selected candidates with mu > 0.28 as/yr and R_F > 16 in an area of 1150 square degrees. Then, we separated white dwarfs from late type dwarfs and subdwarfs by means of the reduced proper motion diagram. Finally, spectroscopic follow-up observations were carried out to confirm the white dwarf nature of the selected candidates. We found 41 white dwarfs of which 24 are new discoveries. Here we present the full sample and for each object provide positions, absolute proper motions, photometry, and spectroscopy., Comment: 14 pages, 7 figures, submitted to A&A

The one billion objects in the GSC-II make up a formidable data set for the hunt of peculiar and rare targets such as late type stars, white dwarfs, carbon dwarfs, asteroids, variable stars, etc. Here we present a survey to search for ancient cool white dwarfs, which led to the discovery of several stars with peculiar spectral distributions and extreme physical properties. Finally, we discuss the impact of the GAIA mission with respect to these peculiar and faint white dwarfs., Comment: 6 pages, 2 figures. Proceedings of the Monte Rosa Conference "GAIA spectroscopy, science and technology" Gressoney Saint Jean (Valle d'Aosta, Italy), Sept 9-12, 2002, ed. U. Munari, ASP Conf. Ser., in press

We report the discovery of a new carbon rich white dwarf that was identified during a proper motion survey for cool white dwarfs based on photographic material used for the construction of the Guide Star Catalog II. Its large proper motion (0.48 arcsec/yr) and faint apparent magnitude (V = 18.7) suggest a nearby object of low luminosity. A low-resolution spectrum taken with the William Herschel Telescope clearly shows strong C2 Deslandres-d'Azambuja and Swan bands, which identify the star as a DQ white dwarf. The strength of the Deslandres-d'Azambuja bands and the depression of the continuum in the Swan-band region are signs of enhanced carbon abundance for the given Teff. Comparison of our spectrophotometric data to published synthetic spectra suggests 6000 K < Teff < 8000 K although further analysis with specialized synthetic models appear necessary to derive both Teff and chemical composition. Finally, the range of spatial velocity estimated for this object makes it a likely member of the halo or thick disk population., Comment: Accepted for publication in A&A Letters, 4 pages, 2 figures

In the construction of an X-ray selected sample of galaxy clusters for cosmological studies, we have assembled a sample of 495 X-ray sources found to show extended X-ray emission in the first processing of the ROSAT All-Sky Survey. The sample covers the celestial region with declination $\delta \ge 0\deg $ and galactic latitude $|b_{II}| \ge 20\deg $ and comprises sources with a count rate $\ge 0.06$ counts s$^{-1}$ and a source extent likelihood of 7. In an optical follow-up identification program we find 378 (76%) of these sources to be clusters of galaxies. ..., Comment: 61 pages; ApJS in press; fixed bug in table file; also available at (better image quality) http://www.xray.mpe.mpg.de/theorie/NORAS/