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Previous results in the literature have found the young inner-disc open cluster NGC 6705 to be mildly α-enhanced. We examined this possibility via an independent chemical abundance analysis for 11 red-giant members of NGC 6705. The analysis is based on near-infrared APOGEE spectra and relies on LTE calculations using spherical model atmospheres and radiative transfer. We find a mean cluster metallicity of |$\rm [Fe/H] = +0.13 \pm 0.04$|⁠ , indicating that NGC 6705 is metal-rich, as may be expected for a young inner-disc cluster. The mean α-element abundance relative to iron is |$\rm \langle [\alpha /Fe]\rangle =-0.03 \pm 0.05$|⁠ , which is not at odds with expectations from general Galactic abundance trends. NGC 6705 also provides important probes for studying stellar mixing, given its turn-off mass of M ∼ 3.3 M⊙. Its red giants have low 12C abundances ([12C/Fe] = −0.16) and enhanced 14N abundances ([14N/Fe] = +0.51), which are key signatures of the first dredge-up on the red giant branch. An additional signature of dredge-up was found in the Na abundances, which are enhanced by [Na/Fe] = +0.29, with a very small non-LTE correction. The 16O and Al abundances are found to be near-solar. All of the derived mixing-sensitive abundances are in agreement with stellar models of approximately 3.3 M⊙ evolving along the red giant branch and onto the red clump. As found in young open clusters with similar metallicities, NGC 6705 exhibits a mild excess in the s-process element cerium with |$\rm [Ce/Fe] = +0.13\pm 0.07$|⁠. [ABSTRACT FROM AUTHOR]

Gradients in the stellar populations (SP) of galaxies – e.g. in age, metallicity, stellar initial mass function (IMF) – can result in gradients in the stellar-mass-to-light ratio, M */ L. Such gradients imply that the distribution of the stellar mass and light is different. For old SPs, e.g. in early-type galaxies at z  ∼ 0, the M */ L gradients are weak if driven by variations in age and metallicity, but significantly larger if driven by the IMF. A gradient which has larger M */ L in the centre increases the estimated total stellar mass (M *) and reduces the scale which contains half this mass (R e ,*), compared to when the gradient is ignored. For the IMF gradients inferred from fitting MILES simple SP models to the H β, 〈Fe〉, [MgFe], and TiO2SDSS absorption lines measured in spatially resolved spectra of early-type galaxies in the MaNGA survey, the fractional change in R e ,* can be significantly larger than that in M *, especially when the light is more centrally concentrated. The R e ,*– M * correlation which results from accounting for IMF gradients is offset to smaller sizes by 0.3 dex compared to when these gradients are ignored. Comparisons with 'quiescent' galaxies at higher z must account for evolution in SP gradients (especially age and IMF) and in the light profile before drawing conclusions about how R e ,* and M * evolve. The implied merging between higher z and the present is less contrived if R e ,*/ Re at z  ∼ 0 is closer to our IMF-driven gradient calibration than to unity. [ABSTRACT FROM AUTHOR]

We find 132 face-on and low inclination galaxies with central star formation driven biconical gas outflows (FSFB) in the SDSS MaNGA (Mapping Nearby Galaxies at APO) survey. The FSFB galaxies show either double peaked or broadened emission line profiles at their centres. The peak and maximum outflow velocities are 58 and 212 km s−1, respectively. The gas velocity dispersion reveals a mild dependence on the central star formation surface density compatible with models of gas dispersion powered by the Jeans instability in gas clumps or by gas turbulence dissipation. We estimate the gas outflow rate and conclude that the central gas depletion time does not depend on galactic mass. In turn, the ratio of the gas outflow rate to the gas consumption rate by the star formation is low in massive galaxies and high in low mass objects, while the star formation is a more rapid process of the gas consumption. We compare properties of the FSFB galaxies with a control sample of 375 comparison galaxies and find that the FSFB objects have high central concentration of star formation and also younger central stellar population with respect to their periphery. We analysed the environment of the galaxies and identified nearby satellites and elements of low surface brightness structure. We see that many tidal-enhanced features that can be assigned to early and intermediate stages of galactic interaction are much more frequent in the FSFB galaxies with respect to the comparison sample. We conclude that the gas should be replenished via the accretion from small satellites. [ABSTRACT FROM AUTHOR]

We present a catalogue of 16 551 edge-on galaxies created using the public DR2 data of the Pan-STARRS survey. The catalogue covers the three quarters of the sky above Dec. = −30°. The galaxies were selected using a convolutional neural network, trained on a sample of edge-on galaxies identified earlier in the SDSS survey. This approach allows us to dramatically improve the quality of the candidate selection and perform a thorough visual inspection in a reasonable amount of time. The catalogue provides homogeneous information on astrometry, SExtractor photometry, and non-parametric morphological statistics of the galaxies. The photometry is reliably for objects in the 13.8–17.4 r -band magnitude range. According to the HyperLeda data base, redshifts are known for about 63 per cent of the galaxies in the catalogue. Our sample is well separated into the red sequence and blue cloud galaxy populations. The edge-on galaxies of the red sequence are systematically Δ(g − i) ≈ 0.1 mag redder than galaxies oriented at an arbitrary angle to the observer. We found a variation of the galaxy thickness with the galaxy colour. The red sequence galaxies are thicker than the galaxies of the blue cloud. In the blue cloud, on average, thinner galaxies turn out to be bluer. In the future, based on this catalogue it is intended to explore the three-dimensional structure of galaxies of different morphologies, as well as to study the scaling relations for discs and bulges. [ABSTRACT FROM AUTHOR]

We continue to search for LBV stars in galaxies outside the Local Group. In this work, we have investigated four luminous stars in NGC 4449. Multiple spectral observations carried out for J122810.94+440540.6, J122811.70+440550.9, and J122809.72+440514.8 revealed the emission features in their spectra that are characteristic of LBVs. Photometry showed noticeable brightness changes of J122809.72+440514.8 (Δ I  = 0.69 ± 0.13 m ) and J122817.83+440630.8 (Δ R  = 2.15 ± 0.13 m ), while the variability of J122810.94+440540.6 and J122811.70+440550.9 does not exceed 0.3 m regardless of the filter. We have obtained estimates of the interstellar reddening, photosphere temperatures, and bolometric luminosities log (L Bol/L⊙) ≈ 5.24–6.42. Using the cmfgen code, we have modelled the spectrum of the cold state of J122809.72+440514.8 (⁠|$T_{\text{eff}}=9300\,$|  K) and have obtained possible value of the mass-loss rate |$\dot{M} = 5.2\times 10^{-3}\, \mathrm{M}_{\odot }\, \mathrm{yr}^{-1}$|⁠. Based on the observational properties, J122809.72+440514.8 and J122817.83+440630.8 were classified as LBVs, while the other two stars were classified as LBV candidates or B[e]-supergiants candidates. [ABSTRACT FROM AUTHOR]

We present the results of a search for optical candidates of ultraluminous X-ray sources (ULXs) in two dwarf galaxies, NGC 4861 and NGC 4449, using Hubble Space Telescope (HST) archival data. With precise astrometry, we confirm that NGC 4861 X1 is associated with an H  ii complex and we conclude that NGC 4861 X2 resides in a young star group of mass 400 ± 80 M⊙. We also find that NGC 4449 X7 is associated with three optical candidates within an error radius of 0.2 arcsec at the 90 |${{\ \rm per\ cent}}$| confidence level. Absolute magnitudes (M v) of these candidates are determined as −5.0 and −4.1. The age and mass values for the three candidates are estimated as 40–50 Myr and ∼8 M⊙, respectively, using stellar evolutionary tracks. The locations of optical candidates suggest a possible association with a nearby group of stars. In addition, we analysed previously unused archival data of XMM–Newton ,  Chandra , and Swift where the sources were detected. Although the X-ray spectral data do not allow us to discriminate between physical models, long-term data at hand are consistent with the sources being in luminous hard states. [ABSTRACT FROM AUTHOR]

The second phase of the APOGEE survey is providing near-infrared (near-IR), high-resolution, high signal-to-noise spectra of stars in the halo, disc, bar, and bulge of the Milky Way. The near-IR spectral window is especially important in the study of the Galactic bulge, where stars are obscured by the dust and gas of the disc in its line of sight. We present a chemical characterization of the globular cluster NGC 6544 with high-resolution spectroscopy. The characterization of the cluster chemical fingerprint, given its status of 'interloper' towards the Galactic bulge and clear signatures of tidal disruption in its core is crucial for future chemical tagging efforts. Cluster members were selected from the DR16 of the APOGEE survey, using chemodynamical criteria of individual stars. A sample of 23 members of the cluster was selected. An analysis considering the intracluster abundance variations, known as anticorrelations is given. According to the red giant branch (RGB) content of the cluster, the iron content and α-enhancement are [Fe/H] = −1.44 ± 0.04 dex and [α/Fe] = 0.20 ± 0.04 dex, respectively. Cluster members show a significant spread in [Fe/H] and [Al/Fe] that is larger than expected based on measurement errors. An [Al/Fe] spread, signal of an Mg–Al anticorrelation is observed and used to constrain the cluster mass budget, along with C, N, Mg, Si, K, Ca, and Ce element variations discussed. Across all the analysed evolutionary stages (RGB and asymptotic giant branch), about ∼2/3 (14 out of 23) show distinct chemical patterns, possibly associated with second-generation stars. [ABSTRACT FROM AUTHOR]

Gas-phase abundances and abundance gradients provide much information on past stellar generations, and are powerful probes of how galaxies evolve. Gas abundance gradients in galaxies have been studied as functions of galaxies' mass and size individually, but have largely not been considered across the galaxy mass–size plane. Thus, we investigate gas-phase abundance gradients across this plane, using a sample of over 1000 galaxies selected from the MApping Nearby Galaxies at APO (MaNGA) spectroscopic survey. We find that gradients vary systematically such that above 1010 M⊙, smaller galaxies display flatter gradients than larger galaxies at a given stellar mass. This mass–size behaviour cannot be explained by instrumental effects, nor is it simply a reflection of known trends between gradients and morphology. We explore multiple possibilities for a physical origin for this pattern, though further work is needed to establish a firm physical interpretation. [ABSTRACT FROM AUTHOR]

We study five luminous blue variable (LBV) candidates in the Andromeda galaxy and one more (MN112) in the Milky Way. We obtain the same-epoch near-infrared (NIR) and optical spectra on the 3.5-m telescope at the Apache Point Observatory and on the 6-m telescope of the SAO RAS. The candidates show typical LBV features in their spectra: broad and strong hydrogen lines, He  i , Fe  ii , and [Fe  ii ] lines. We estimate the temperatures, reddening, radii and luminosities of the stars using their spectral energy distributions. Bolometric luminosities of the candidates are similar to those of known LBV stars in the Andromeda galaxy. One candidate, J004341.84+411112.0, demonstrates photometric variability (about 0.27 mag in the V band), which allows us to classify it as an LBV. The star J004415.04+420156.2 shows characteristics typical of B[e] supergiants. The star J004411.36+413257.2 is classified as a Fe  ii star. We confirm that the stars J004621.08+421308.2 and J004507.65+413740.8 are warm hypergiants. We obtain for the first time the NIR spectrum of the Galactic LBV candidate MN112. We use both optical and NIR spectra of MN112 for comparison with similar stars in M31 and notice identical spectra and the same temperature in J004341.84+411112.0. This allows us to confirm that MN112 is an LBV, which should show its brightness variability in longer time span observations. [ABSTRACT FROM AUTHOR]

We use the first release of the SDSS/MaStar stellar library comprising ∼9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the wavelength range 0.36–1.03 µm and share the same spectral resolution (⁠|$R\sim 1800$|⁠) and flux calibration as the SDSS-IV/MaNGA galaxy data. The parameter space covered by the stellar spectra collected thus far allows the calculation of models with ages and chemical composition in the range |$\rm {\mathit{ t}\gt 200 \,Myr, -2 \lt = [Z/H] \lt = + 0.35}$|⁠ , which will be extended as MaStar proceeds. Notably, the models include spectra for dwarf main-sequence stars close to the core H-burning limit, as well as spectra for cold, metal-rich giants. Both stellar types are crucial for modelling λ > 0.7 µm absorption spectra. Moreover, a better parameter coverage at low metallicity allows the calculation of models as young as 500 Myr and the full account of the blue horizontal branch phase of old populations. We present models adopting two independent sets of stellar parameters (T eff, log  g , [Z/H]). In a novel approach, their reliability is tested 'on the fly' using the stellar population models themselves. We perform tests with Milky Way and Magellanic Clouds globular clusters, finding that the new models recover their ages and metallicities remarkably well, with systematics as low as a few per cent for homogeneous calibration sets. We also fit a MaNGA galaxy spectrum, finding residuals of the order of a few per cent comparable to the state-of-art models, but now over a wider wavelength range. [ABSTRACT FROM AUTHOR]

We present the results of the archaeological analysis of the stellar populations of a sample of ∼4000 galaxies observed by the SDSS-IV MaNGA survey using pipe3d. Based on this analysis we extract a sample of ∼150 000 star formation rates (SFRs) and stellar masses that mimic a single cosmological survey covering the redshift range between |$z$| ∼ 0 and |$z$| ∼ 7. We confirm that the star-forming main sequence holds as a tight relation in this range of redshifts, evolving in both the zero-point and slope. This evolution is different for local star-forming (SFGs) and retired (RGs) galaxies, with the latter presenting a stronger evolution in the zero-point and a weaker evolution in the slope. The fraction of RGs decreases rapidly with |$z$|⁠, particularly for RGs at |$z$| ∼ 0. We detect RGs well above |$z$| > 1, although not all of them are progenitors of local RGs. Finally, adopting the required corrections to make the survey complete in mass in a limited volume, we recover the cosmic SFR, stellar-mass density, and average specific SFR histories of the Universe in this wide range of look-back times. Our derivations agree with those reported by various cosmological surveys. We demonstrate that the progenitors of local RGs were more actively forming stars in the past, contributing to most of the cosmic SFR density at |$z$| > 0.5, and to most of the cosmic stellar-mass density at any redshift. They suffer a general quenching in the SFR at z ∼  0.35. Below this redshift the progenitors of local SFGs dominate the SFR density of the Universe. [ABSTRACT FROM AUTHOR]

We construct a multiparametric Tully–Fisher (TF) relation for a large sample of edge-on galaxies from the Revised Flat Galaxy Catalog using H  i data from the Extragalactic Distance Database and parameters from the edge-on disc galaxies catalogue. We incorporate a variety of additional parameters including structural parameters of edge-on galaxies in different bandpasses. Besides the rotation curve maximum, only the H  i -to-optical luminosity ratio and optical colours play a statistically significant role in the multiparametric TF relation. We are able to decrease the standard deviation of the multiparametric TF relation down to 0.32 mag, which is at the level of best modern samples of galaxies used for studies of the matter motion in the Universe via the TF relation. [ABSTRACT FROM AUTHOR]

We present a detailed photometric study of a sample of 22 edge-on galaxies with clearly visible X-shaped structures. We propose a novel method to derive geometrical parameters of these features, along with the parameters of their host galaxies based on the multi-component photometric decomposition of galactic images. To include the X-shaped structure into our photometric model, we use the IMFIT package, in which we implement a new component describing the X-shaped structure. This method is applied for a sample of galaxies with available Sloan Digital Sky Survey and Spitzer IRAC 3.6 μm observations. In order to explain our results, we perform realistic N-body simulations of aMilkyWay-type galaxy and compare the observed and the model X-shaped structures. Our main conclusions are as follows: (1) galaxies with strong X-shaped structures reside in approximately the same local environments as field galaxies; (2) the characteristic size of the X-shaped structures is about 2/3 of the bar size; (3) there is a correlation between the X-shaped structure size and its observed flatness: the larger structures are more flattened; (4) our N-body simulations qualitatively confirm the observational results and support the bar-driven scenario for the X-shaped structure formation. [ABSTRACT FROM AUTHOR]

We study the properties of galaxies with very thin discs (VTDs) using a sample of 85 objects whose stellar disc radial-to-vertical scale ratio determined from photometric decomposition, exceeds 9. We present evidences of similarities between the VTD galaxies and low surface brightness (LSB) disc galaxies, and conclude that both small and giant LSB galaxies may reveal themselves as VTD, edge-on galaxies. Our VTD galaxies are mostly bulgeless, and those with large radial scalelength tend to have redder colours. We performed spectral observations of 22 VTD galaxies with the Dual Imaging Spectrograph on the 3.5 m telescope at the Apache Point Observatory. The spectra with good resolution (R ~ 5000) allow us to determine the distance and the ionized gas rotation curve maximum for the galaxies. Our VTD galaxies have low dust content, in contrast to regular disc galaxies. Apparently, VTD galaxies reside in specific cosmological low-density environments and tend to have less connection with filaments. Comparing a toy model that assumes marginally low star formation in galactic discs with obtained gas kinematics data, we conclude that there is a threshold central surface density of about 88 Mʘ?pc-2, which we observe in the case of very thin, rotationally supported galactic discs. [ABSTRACT FROM AUTHOR]

We study the internal radial gradients of stellar population properties within 1.5 Re and analyse the impact of galaxy environment. We use a representative sample of 721 galaxies with masses ranging between 109 M⊙ and 1011.5 M⊙ from he SDSS-IV survey MaNGA. We split this sample by morphology into early-type and late-type galaxies. Using the full spectral fitting code FIREFLY, we derive the light and mass-weighted stellar population properties, age and metallicity, and calculate the gradients of these properties. We use three independent methods to quantify galaxy environment, namely the Nth nearest neighbour, the tidal strength parameter Q and distinguish between central and satellite galaxies. In our analysis, we find that early-type galaxies generally exhibit shallow light-weighted age gradients in agreement with the literature and mass-weighted median age gradients tend to be slightly positive. Late-type galaxies, instead, have negative light-weighted age gradients. We detect negative metallicity gradients in both early- and late-type galaxies that correlate with galaxy mass, with the gradients being steeper and the correlation with mass being stronger in late-types. We find, however, that stellar population gradients, for both morphological classifications, have no significant correlation with galaxy environment for all three characterizations of environment. Our results suggest that galaxy mass is the main driver of stellar population gradients in both early and late-type galaxies, and any environmental dependence, if present at all, must be very subtle. [ABSTRACT FROM AUTHOR]

We study the properties of 66 galaxies with kinematically misaligned gas and stars from MaNGA survey. The fraction of kinematically misaligned galaxies varies with galaxy physical parameters, i.e. M*, SFR and sSFR. According to their sSFR, we further classify these 66 galaxies into three categories, 10 star-forming, 26 ‘Green Valley’ and 30 quiescent ones. The properties of different types of kinematically misaligned galaxies are different in that the star-forming ones have positive gradient in Dn4000 and higher gas-phase metallicity, while the green valley/quiescent ones have negative Dn4000 gradients and lower gas-phase metallicity on average. There is evidence that all types of the kinematically misaligned galaxies tend to live in more isolated environment. Based on all these observational results, we propose a scenario for the formation of star-forming galaxies with kinematically misaligned gas and stars − the progenitor accretes misaligned gas from a gas-rich dwarf or cosmic web, the cancellation of angular momentum from gas–gas collisions between the pre-existing gas and the accreted gas largely accelerates gas inflow, leading to fast centrally concentrated star formation. The higher metallicity is due to enrichment from this star formation. For the kinematically misaligned green valley and quiescent galaxies, they might be formed through gas-poor progenitors accreting kinematically misaligned gas from satellites which are smaller in mass. [ABSTRACT FROM AUTHOR]

We performed spectroscopy of five luminous blue variable (LBV) candidates and two known LBV stars (AE And and Var A-1) in M31. We obtained the same-epoch near-infrared (NIR) and optical spectra of these stars. The NIR spectra were taken with the Triplespec spectrograph at the 3.5-m telescope at the Apache Point Observatory, and the optical spectroscopy was carried out using the SCORPIO focal reducer at the 6-m BTA telescope (Special Astrophysical Observatory of the Russian Academy of Science). The candidates demonstrate typical LBV features in their spectra: broad and strong hydrogen lines, and He i, Fe ii and [Fe ii] lines. All our candidates show photometric variability. We develop a new approach to the estimation of LBV parameters based on the inherent property of LBVs to change their spectral type at constant bolometric luminosity. We compare the spectral energy distributions of the variable stars obtained in two or more different states, and we estimate the temperatures, reddening, radii and luminosities of the stars using this method. Two considered candidates (J004526.62+415006.3 and J004051.59+403303.0) have to be classified as new LBV stars. Two more candidates are, apparently, B[e] supergiants. The nature of one more star (J004350.50 + 414611.4) is not clear. It does not show obvious LBV-like variability and remains an LBV candidate. [ABSTRACT FROM AUTHOR]

Using N-body simulations (N ∼ 106–107), we examine how a non-axisymmetric dark halo affects the dynamical evolution of the structure in collisionless (stellar) discs. We demonstrate how the model parameters such as mass of the halo, initial conditions in the disc and the halo axis ratio affect morphology and kinematics of the stellar discs. We show that a non-axisymmetric halo can generate a large-scale spiral density pattern in the embedded stellar disc. The pattern is observed in the disc for many periods of its revolution, even if the disc is gravitationally overstable. The growth of the spiral arms is not accompanied by significant dynamical heating of the disc, irrelevant to its initial parameters. We also investigate transformation of the dark halo’s shape driven by the long-lived spiral pattern in the disc. We show that the analysis of the velocity field in the stellar disc and in the spiral pattern gives us a possibility to figure out the spatial orientation of the triaxial dark halo and to measure the triaxiality. [ABSTRACT FROM AUTHOR]

We perform a spectroscopic analysis of 492 450 galaxy spectra from the first two years of observations of the Sloan Digital Sky Survey (SDSS) III/Baryonic Oscillation Spectroscopic Survey (BOSS) collaboration. This data set has been released in the ninth SDSS data release, the first public data release of BOSS spectra. We show that the typical signal-to-noise ratio of BOSS spectra, despite being low, is sufficient to measure stellar velocity dispersion and emission line fluxes for individual objects. We show that the typical velocity dispersion of a BOSS galaxy is ∼240 km s−1. The typical error in the velocity dispersion measurement is 14 per cent, and 93 per cent of BOSS galaxies have velocity dispersions with an accuracy of better than 30 per cent. The distribution in velocity dispersion is redshift independent between redshifts 0.15 and 0.7, which reflects the survey design targeting massive galaxies with an approximately uniform mass distribution in this redshift interval. We show that emission lines can be measured on BOSS spectra. However, the majority of BOSS galaxies lack detectable emission lines, as is to be expected because of the target selection design towards massive galaxies. We analyse the emission line properties and present diagnostic diagrams using the emission lines [O ii], Hβ, [O iii], Hα and [N ii] (detected in about 4 per cent of the galaxies) to separate star-forming objects and active galactic nuclei (AGN). We show that the emission line properties are strongly redshift dependent and that there is a clear correlation between observed frame colours and emission line properties. Within in the low-z sample (LOWZ) around 0.15 < z < 0.3, half of the emission line galaxies have low-ionization nuclear emission-line region (LINER)-like emission line ratios, followed by Seyfert-AGN-dominated spectra, and only a small fraction of a few per cent are purely star-forming galaxies. AGN and LINER-like objects, instead, are less prevalent in the high-z sample (CMASS) around 0.4 < z < 0.7, where more than half of the emission line objects are star forming. This is a pure selection effect caused by the non-detection of weak Hβ emission lines in the BOSS spectra. Finally, we show that star-forming, AGN and emission line free galaxies are well separated in the g − r versus r − i target selection diagram. [ABSTRACT FROM AUTHOR]

We present a new public archive of light-motion curves in Sloan Digital Sky Survey (SDSS) Stripe 82, covering 99° in right ascension from to and spanning in declination from to , for a total sky area of ∼249 deg2. Stripe 82 has been repeatedly monitored in the and z bands over a seven-year baseline. Objects are cross-matched between runs, taking into account the effects of any proper motion. The resulting catalogue contains almost 4 million light-motion curves of stellar objects and galaxies. The photometry are recalibrated to correct for varying photometric zero-points, achieving ∼20 and 30 mmag rms accuracy down to 18 mag in the and z bands for point sources and extended sources, respectively. The astrometry are recalibrated to correct for inherent systematic errors in the SDSS astrometric solutions, achieving ∼32 and 35 mas rms accuracy down to 18 mag for point sources and extended sources, respectively. For each light-motion curve, 229 photometric and astrometric quantities are derived and stored in a higher level catalogue. On the photometric side, these include mean exponential and point spread function (PSF) magnitudes along with uncertainties, rms scatter, per degree of freedom, various magnitude distribution percentiles, object type (stellar or galaxy), and eclipse, Stetson and Vidrih variability indices. On the astrometric side, these quantities include mean positions, proper motions as well as their uncertainties and per degree of freedom. The light-motion curve catalogue presented here is complete down to and is at present the deepest large-area photometric and astrometric variability catalogue available. [ABSTRACT FROM AUTHOR]