The ESO-Sculptor Faint Galaxy Redshift Survey: The Photometric Sample

We present the photometric sample of a faint galaxy survey carried out in the southern hemisphere, using CCDs on the 3.60m and NTT-3.5m telescopes at La Silla (ESO). The survey area is a continuous strip of 0.2 deg x 1.53 deg located at high galactic latitude (-83 deg) in the Sculptor constellation. The photometric survey provides total magnitudes in the bands B, V (Johnson) and R (Cousins) to limiting magnitudes of 24.5, 24.0, 23.5 respectively. To these limits, the catalog contains about 9500, 12150, 13000 galaxies in B, V, R bands respectively and is the first large digital multi-colour photometric catalog at this depth. This photometric survey also provides the entry catalog for a fully-sampled redshift survey of ~ 700 galaxies with R < 20.5 (Bellanger et al. 1995). In this paper, we describe the photometric observations and the steps used in the data reduction. The analysis of objects and the star-galaxy separation with a neural network are performed using SExtractor, a new photometric software developed by E. Bertin (1996). The photometric accuracy of the resulting catalog is ~ 0.05 mag for R < 22. The differential galaxy number counts in B, V, R are in good agreement with previously published CCD studies and confirm the evidence for significant evolution at faint magnitudes as compared to a standard non evolving model (by factors 3.6, 2.6, 2.1). The galaxy colour distributions B-R, B-V of our sample show a blueing trend of ~ 0.5 mag between 21 < R < 23.5 in contrast to the V-R colour distribution where no significant evolution is observed.Comment: LATEX, 18 Postscript figures, 20 pages. To appear July 1997. Modified version of article. Abstract corrected for missing lin

Photometric Solutions for Detached Eclipsing Binaries: selection of ideal distance indicators in the SMC

Detached eclipsing binary stars provide a robust one-step distance determination to nearby galaxies. As a by-product of Galactic microlensing searches, catalogs of thousands of variable stars including eclipsing binaries have been produced by the OGLE, MACHO and EROS collaborations. We present photometric solutions for detached eclipsing binaries in the Small Magellanic Cloud (SMC) discovered by the OGLE collaboration. The solutions were obtained with an automated version of the Wilson-Devinney program. By fitting mock catalogs of eclipsing binaries we find that the normalized stellar radii (particularly their sum) and the surface brightness ratio are accurately described by the fitted parameters and estimated standard errors, despite various systematic uncertainties. In many cases these parameters are well constrained. In addition we find that systems exhibiting complete eclipses can be reliably identified where the fractional standard errors in the radii are small. We present two quantitatively selected sub-samples of eclipsing binaries that will be excellent distance indicators. These can be used both for computation of the distance to the SMC and to probe its structure. One particularly interesting binary has a very well determined solution, exhibits complete eclipses, and is comprised of well detached G-type, class $II$ giants.Comment: 29 pages, 12 figures. To be published in Ap

Interacting Binaries with Eccentric Orbits. Secular Orbital Evolution Due To Conservative Mass Transfer

We investigate the secular evolution of the orbital semi-major axis and eccentricity due to mass transfer in eccentric binaries, assuming conservation of total system mass and orbital angular momentum. Assuming a delta function mass transfer rate centered at periastron, we find rates of secular change of the orbital semi-major axis and eccentricity which are linearly proportional to the magnitude of the mass transfer rate at periastron. The rates can be positive as well as negative, so that the semi-major axis and eccentricity can increase as well as decrease in time. Adopting a delta-function mass-transfer rate of 10^{-9} M_\sun {\rm yr}^{-1} at periastron yields orbital evolution timescales ranging from a few Myr to a Hubble time or more, depending on the binary mass ratio and orbital eccentricity. Comparison with orbital evolution timescales due to dissipative tides furthermore shows that tides cannot, in all cases, circularize the orbit rapidly enough to justify the often adopted assumption of instantaneous circularization at the onset of mass transfer. The formalism presented can be incorporated in binary evolution and population synthesis codes to create a self-consistent treatment of mass transfer in eccentric binaries.Comment: 16 pages, 8 figures, Accepted by The Astrophysical Journa

Energy state distributions of the P(b) centers at the (100), (110), and (111) Si/SiO(2) interfaces investigated by Laplace deep level transient spectroscopy

The energy distribution of the P(b) centers at the Si/SiO(2) interface has been determined using isothermal laplace deep level transient spectroscopy. For the (111) and (110) interface orientations, the distributions are similar and centered at 0.38 eV below the silicon conduction band. This is consistent with only P(b0) states being present. For the (100) orientation, two types of the interface states are observed: one similar to the (111) and (110) orientations while the other has a negative-U character in which the emission rate versus surface potential dependence is qualitatively different from that observed for P(b0) and is presumed to be P(b1). (C) 2008 American Institute of Physics. (DOI: 10.1063/1.2939001

IPHAS J062746.41+014811.3: a deeply eclipsing intermediate polar

We present time-resolved photometry of a cataclysmic variable discovered in the Isaac Newton Telescope Photometric Halpha Survey of the northern galactic plane, IPHAS J062746.41+014811.3 and classify the system as the fourth deeply eclipsing intermediate polar known with an orbital period of Porb=8.16 h, and spin period of Pspin=2210 s. The system shows mild variations of its brightness, that appear to be accompanied by a change in the amplitude of the spin modulation at optical wavelengths, and a change in the morphology of the eclipse profile. The inferred magnetic moment of the white dwarf is mu_wd = 6-7 x 10^33 Gcm^3, and in this case IPHAS J0627 will either evolve into a short-period EX Hya-like intermediate polar with a large Pspin\Porb ratio, or, perhaps more likely, into a synchronised polar. Swift observations show that the system is an ultraviolet and X-ray source, with a hard X-ray spectrum that is consistent with those seen in other intermediate polars. The ultraviolet light curve shows orbital modulation and an eclipse, while the low signal-to-noise ratio X-ray light curve does not show a significant modulation on the spin period. The measured X-ray flux is about an order of magnitude lower than would be expected from scaling by the optical fluxes of well-known X-ray selected intermediate polars.Comment: 34 pages, 9 figures, accepted for publication in Ap

An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent

In the era of precision cosmology it is essential to determine the Hubble Constant with an accuracy of 3% or better. Currently, its uncertainty is dominated by the uncertainty in the distance to the Large Magellanic Cloud (LMC) which as the second nearest galaxy serves as the best anchor point of the cosmic distance scale. Observations of eclipsing binaries offer a unique opportunity to precisely and accurately measure stellar parameters and distances. The eclipsing binary method was previously applied to the LMC but the accuracy of the distance results was hampered by the need to model the bright, early-type systems used in these studies. Here, we present distance determinations to eight long-period, late- type eclipsing systems in the LMC composed of cool giant stars. For such systems we can accurately measure both the linear and angular sizes of their components and avoid the most important problems related to the hot early-type systems. Our LMC distance derived from these systems is demonstrably accurate to 2.2 % (49.97 +/- 0.19 (statistical) +/- 1.11 (systematic) kpc) providing a firm base for a 3 % determination of the Hubble Constant, with prospects for improvement to 2 % in the future.Comment: 34 pages, 5 figures, 13 tables, published in the Nature, a part of our data comes from new unpublished OGLE-IV photometric dat

The `666' collaboration on OGLE transits: I. Accurate radius of the planets OGLE-TR-10b and OGLE-TR-56b with VLT deconvolution photometry

Transiting planets are essential to study the structure and evolution of extra-solar planets. For that purpose, it is important to measure precisely the radius of these planets. Here we report new high-accuracy photometry of the transits of OGLE-TR-10 and OGLE-TR-56 with VLT/FORS1. One transit of each object was covered in Bessel V and R filters, and treated with the deconvolution-based photometry algorithm DECPHOT, to ensure accurate millimagnitude light curves. Together with earlier spectroscopic measurements, the data imply a radius of 1.22 +0.12-0.07 R_J for OGLE-TR-10b and 1.30 +- 0.05 R_J for OGLE-TR-56b. A re-analysis of the original OGLE photometry resolves an earlier discrepancy about the radius of OGLE-TR-10. The transit of OGLE-TR-56 is almost grazing, so that small systematics in the photometry can cause large changes in the derived radius. Our study confirms both planets as inflated hot Jupiters, with large radii comparable to that of HD 209458$b$ and at least two other recently discovered transiting gas giants.Comment: Fundamental updates compared to previous version; accepted for publication in Astronomy & Astrophysic

Binary Quasars in the Sloan Digital Sky Survey: Evidence for Excess Clustering on Small Scales

We present a sample of 218 new quasar pairs with proper transverse separations R_prop < 1 Mpc/h over the redshift range 0.5 < z < 3.0, discovered from an extensive follow up campaign to find companions around the Sloan Digital Sky Survey and 2dF Quasar Redshift Survey quasars. This sample includes 26 new binary quasars with separations R_prop < 50 kpc/h (theta < 10 arcseconds), more than doubling the number of such systems known. We define a statistical sample of binaries selected with homogeneous criteria and compute its selection function, taking into account sources of incompleteness. The first measurement of the quasar correlation function on scales 10 kpc/h < R_prop < 400 kpc/h is presented. For R_prop < 40 kpc/h, we detect an order of magnitude excess clustering over the expectation from the large scale R_prop > 3 Mpc/h quasar correlation function, extrapolated down as a power law to the separations probed by our binaries. The excess grows to ~ 30 at R_prop ~ 10 kpc/h, and provides compelling evidence that the quasar autocorrelation function gets progressively steeper on sub-Mpc scales. This small scale excess can likely be attributed to dissipative interaction events which trigger quasar activity in rich environments. Recent small scale measurements of galaxy clustering and quasar-galaxy clustering are reviewed and discussed in relation to our measurement of small scale quasar clustering.Comment: 25 pages, 12 figures, 9 tables. Submitted to the Astronomical Journa

Archiwum i księgozbiór Naukowego Instytutu Polsko-Skandynawskiego

Instytut Polsko-Skandynawski powstawał w ramach polskiego państwa na uchodźstwie, w okresie gdy Polska była częścią bloku sowieckiego. Założony w 1985 r. z sie dzibą w Kopenhadze IPS dysponuje starszymi o 15 lat archiwum i księgozbiorem. Dokumentacja zajmuje ok. 40 metrów bieżących. Składają się na nią materiały do rozpraw naukowych, korespondencja z członkami jednostki i instytucjami, źródła do dziejów emigracji polskiej i jej organizacji w krajach skandynawskich. Księgozbiór liczy ok. 2000 tomów. Znajdują się w nim prace naukowe członków instytutu, „Rocznik Polskiego Towarzystwa Naukowego na Obczyźnie”, „Acta Cassubiana”, publikacje własne placówki, literatura w językach skandynawskich dotycząca Polski, polska literatura poświęcona dziejom Gdańska i Pomorza, czasopisma ukazujące się poza Polską i inne. Instytut nie miał i nie ma specjalistycznej administracji tymi zbiorami, jak również finansowej możliwości zatrudnienia odpowiedniego personelu. Ze względu na te problemy, gdy stało się to możliwe po przemianach ustrojowych w kraju, dokumentacja oraz księgozbiór są sukcesywnie przekazywane do Archiwum Akt Nowych w Warszawie, Archiwum Emigracji UMK w Toruniu i specjalistycznych bibliotek w Polsce

PANI STEFANIA Z TWÓRCZOŚCIĄ W TLE

Tekst wpomnieniowy.&nbsp