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2. Exploring Cosmic Origins with CORE: Extragalactic Sources in Cosmic Microwave Background Maps

Author

de Zotti, G., Gonzalez-Nuevo, J., Lopez-Caniego, M., Negrello, M., Greenslade, J., Hernandez-Monteagudo, C., Delabrouille, J., Cai, Z.Y., Bonato, M., Achúcarro, A., Ade, P.A.R., Allison, R., Ashdown, M., Ballardini, M., Banday, A.J., Banerji, R., Bartlett, J.G., Bartolo, N., Basak, S., Bersanelli, M., Biesiada, M., Bilicki, M., Bonaldi, A., Bonavera, L., Borrill, J., Bouchet, F.R., Boulanger, F., Brinckmann, T., Bucher, M., Burigana, C., Buzzelli, A., Calvo, M., Carvalho, C.S., Castellano, M.G., Challinor, A., Chluba, J., Clements, D.L., Clesse, S., Colafrancesco, S., Colantoni, I., Coppolecchia, Alessandro, Crook, M., D’Alessandro, Giuseppe, De Bernardis, P., de Gasperis, G., Diego, J.M., Di Valentino, E., Errard, J., Feeney, S.M., Fernández-Cobos, R., Ferraro, S., Finelli, F., Forastieri, F., Galli, S., Genova-Santos, R.T., Gerbino, M., Grandis, S., Hagstotz, S., Hanany, S., Handley, W., Hervias-Caimapo, C., Hills, M., Hivon, E., Kiiveri, K., Kisner, T.S., Kitching, T., Kunz, M., Kurki-Suonio, H., Lagache, G., Lamagna, L., Lasenby, A., Lattanzi, M., Le Brun, A.M.C., Lesgourgues, J., Lewis, A., Liguori, M., Lindholm, V., Luzzi, G., Maffei, B., Mandolesi, N., Martinez-Gonzalez, E., Martins, C.J.A.P., Masi, S., Massardi, M., McCarthy, D., Melchiorri, A., Melin, J.-B., Molinari, D., Monfardini, A., Natoli, P., Notari, A., Paiella, A., Paoletti, D., Partridge, R.B., Patanchon, G., Piat, M., Pisano, G., Polastri, L., Polenta, G., Pollo, A., Poulin, V., Quartin, M., Remazeilles, M., Roman, M., Rossi, G., Roukema, B.F., Rubino-Martin, J.A., Salvati, L., Scott, D., Serjeant, S., Tartari, A., Toffolatti, L., Tomasi, M., Trappe, Neil, Triqueneaux, S., Trombetti, T., Tucci, M., Tucker, C., Valiviita, J., van de Weygaert, R., Van Tent, B., Vennin, V., Vielva, P., Vittorio, N., Young, K., Zannoni, M., de Zotti, G., Gonzalez-Nuevo, J., Lopez-Caniego, M., Negrello, M., Greenslade, J., Hernandez-Monteagudo, C., Delabrouille, J., Cai, Z.Y., Bonato, M., Achúcarro, A., Ade, P.A.R., Allison, R., Ashdown, M., Ballardini, M., Banday, A.J., Banerji, R., Bartlett, J.G., Bartolo, N., Basak, S., Bersanelli, M., Biesiada, M., Bilicki, M., Bonaldi, A., Bonavera, L., Borrill, J., Bouchet, F.R., Boulanger, F., Brinckmann, T., Bucher, M., Burigana, C., Buzzelli, A., Calvo, M., Carvalho, C.S., Castellano, M.G., Challinor, A., Chluba, J., Clements, D.L., Clesse, S., Colafrancesco, S., Colantoni, I., Coppolecchia, Alessandro, Crook, M., D’Alessandro, Giuseppe, De Bernardis, P., de Gasperis, G., Diego, J.M., Di Valentino, E., Errard, J., Feeney, S.M., Fernández-Cobos, R., Ferraro, S., Finelli, F., Forastieri, F., Galli, S., Genova-Santos, R.T., Gerbino, M., Grandis, S., Hagstotz, S., Hanany, S., Handley, W., Hervias-Caimapo, C., Hills, M., Hivon, E., Kiiveri, K., Kisner, T.S., Kitching, T., Kunz, M., Kurki-Suonio, H., Lagache, G., Lamagna, L., Lasenby, A., Lattanzi, M., Le Brun, A.M.C., Lesgourgues, J., Lewis, A., Liguori, M., Lindholm, V., Luzzi, G., Maffei, B., Mandolesi, N., Martinez-Gonzalez, E., Martins, C.J.A.P., Masi, S., Massardi, M., McCarthy, D., Melchiorri, A., Melin, J.-B., Molinari, D., Monfardini, A., Natoli, P., Notari, A., Paiella, A., Paoletti, D., Partridge, R.B., Patanchon, G., Piat, M., Pisano, G., Polastri, L., Polenta, G., Pollo, A., Poulin, V., Quartin, M., Remazeilles, M., Roman, M., Rossi, G., Roukema, B.F., Rubino-Martin, J.A., Salvati, L., Scott, D., Serjeant, S., Tartari, A., Toffolatti, L., Tomasi, M., Trappe, Neil, Triqueneaux, S., Trombetti, T., Tucci, M., Tucker, C., Valiviita, J., van de Weygaert, R., Van Tent, B., Vennin, V., Vielva, P., Vittorio, N., Young, K., and Zannoni, M.

Abstract

We discuss the potential of a next generation space-borne Cosmic Microwave Background (CMB) experiment for studies of extragalactic sources. Our analysis has particular bearing on the definition of the future space project, CORE, that has been submitted in response to ESA's call for a Medium-size mission opportunity as the successor of the Planck satellite. Even though the effective telescope size will be somewhat smaller than that of Planck, CORE will have a considerably better angular resolution at its highest frequencies, since, in contrast with Planck, it will be diffraction limited at all frequencies. The improved resolution implies a considerable decrease of the source confusion, i.e. substantially fainter detection limits. In particular, CORE will detect thousands of strongly lensed high-z galaxies distributed over the full sky. The extreme brightness of these galaxies will make it possible to study them, via follow-up observations, in extraordinary detail. Also, the CORE resolution matches the typical sizes of high-z galaxy proto-clusters much better than the Planck resolution, resulting in a much higher detection efficiency; these objects will be caught in an evolutionary phase beyond the reach of surveys in other wavebands. Furthermore, CORE will provide unique information on the evolution of the star formation in virialized groups and clusters of galaxies up to the highest possible redshifts. Finally, thanks to its very high sensitivity, CORE will detect the polarized emission of thousands of radio sources and, for the first time, of dusty galaxies, at mm and sub-mm wavelengths, respectively.

Published
2018

3. International observational campaigns of the last two eclipses in EE Cephei: 2003 and 2008/9

Author

Gałan, C. Mikołajewski, M. Tomov, T. Graczyk, D. Apostolovska, G. Barzova, I. Bellas-Velidis, I. Bilkina, B. Blake, R.M. Bolton, C.T. Bondar, A. Brát, L. Brozek, T. Budzisz, B. Cikała, M. Csák, B. Dapergolas, A. Dimitrov, D. Dobierski, P. Drahus, M. Drózdz, M. Dvorak, S. Elder, L. Fra̧ckowiak, S. Galazutdinov, G. Gazeas, K. Georgiev, L. Gere, B. Goździewski, K. Grinin, V.P. Gromadzki, M. Hajduk, M. Heras, T.A. Hopkins, J. Iliev, I. Janowski, J. Kocián, R. Kołaczkowski, Z. Kolev, D. Kopacki, G. Krzesiński, J. Kučáková, H. Kuligowska, E. Kundera, T. Kurpińska-Winiarska, M. Kuźmicz, A. Liakos, A. Lister, T.A. MacIejewski, G. Majcher, A. Majewska, A. Marrese, P.M. Michalska, G. Migaszewski, C. Miller, I. Munari, U. Musaev, F. Myers, G. Narwid, A. Németh, P. Niarchos, P. Niemczura, E. Ogłoza, W. Öǧmen, Y. Oksanen, A. Osiwała, J. Peneva, S. Pigulski, A. Popov, V. Pych, W. Pye, J. Ragan, E. Roukema, B.F. Rózański, P.T. Semkov, E. Siwak, M. Staels, B. Stateva, I. Stempels, H.C. Stȩšlicki, M. Świerczyński, E. Szymański, T. Tomov, N. Waniak, W. Wiécek, M. Winiarski, M. Wychudzki, P. Zajczyk, A. Zoła, S. Zwitter, T.

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Context. EE Cep is an unusual long-period (5.6 yr) eclipsing binary discovered during the mid-twentieth century. It undergoes almost-grey eclipses that vary in terms of both depth and duration at different epochs. The system consists of a Be type star and a dark dusty disk around an invisible companion. EE Cep together with the widely studied ε Aur are the only two known cases of long-period eclipsing binaries with a dark, dusty disk component responsible for periodic obscurations. Aims. Two observational campaigns were carried out during the eclipses of EE Cep in 2003 and 2008/9 to verify whether the eclipsing body in the system is indeed a dark disk and to understand the observed changes in the depths and durations of the eclipses. Methods. Multicolour photometric data and spectroscopic observations performed at both low and high resolutions were collected with several dozen instruments located in Europe and North America. We numerically modelled the variations in brightness and colour during the eclipses. We tested models with different disk structure, taking into consideration the inhomogeneous surface brightness of the Be star. We considered the possibility of disk precession. Results. The complete set of observational data collected during the last three eclipses are made available to the astronomical community. The 2003 and 2008/9 eclipses of EE Cep were very shallow. The latter is the shallowest among all observed. The very high quality photometric data illustrate in detail the colour evolution during the eclipses for the first time. Two blue maxima in the colour indices were detected during these two eclipses, one before and one after the photometric minimum. The first (stronger) blue maximum is simultaneous with a "bump" that is very clear in all the UBV(RI)C light curves. A temporary increase in the I-band brightness at the orbital phase ∼0.2 was observed after each of the last three eclipses. Variations in the spectral line profiles seem to be recurrent during each cycle. The Na i lines always show at least three absorption components during the eclipse minimum and strong absorption is superimposed on the Hα emission. Conclusions. These observations confirm that the eclipsing object in EE Cep system is indeed a dark, dusty disk around a low luminosity object. The primary appears to be a rapidly rotating Be star that is strongly darkened at the equator and brightened at the poles. Some of the conclusions of this work require verification in future studies: (i) a complex, possibly multi-ring structure of the disk in EE Cep; (ii) our explanation of the "bump" observed during the last two eclipses in terms of the different times of obscuration of the hot polar regions of the Be star by the disk; and (iii) our suggested period of the disk precession (∼11-12 Porb) and predicted depth of about 2m ̇ for the forthcoming eclipse in 2014. © 2012 ESO.

Published
2012

5. On the comoving distance as an arc-length in four dimensions.

Author

Roukema, B.F.

Subjects
*ARC measures, *METAPHYSICAL cosmology, *MEASUREMENT of distances
Abstract

The inner product provides a conceptually and algorithmically simple method for calculating the comoving distance between two cosmological objects given their redshifts, right ascension and declination, and arbitrary constant curvature. The key to this is that just as a distance between two points ‘on’ the surface of the ordinary 2-sphere S[sup 2] is simply an arc-length (angle multiplied by radius) in ordinary Euclidean 3-space E[sup 3], the distance between two points ‘on’ a 3-sphere S[sup 3] (a 3-hyperboloid H[sup 3]) is simply an ‘arc-length’ in Euclidean 4-space E[sup 4] (Minkowski 4-space M[sup 4]), i.e. an ‘hyper-angle’ multiplied by the curvature radius of the 3-sphere (3-hyperboloid). [ABSTRACT FROM AUTHOR]

Published
2001
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6. COBE and global topology: an example of the application of the identified circles principle.

Author

Roukema, B.F.

Subjects
*CIRCLE (Surveying instrument), *ARTIFICIAL satellites, *TOPOLOGY
Abstract

The significance to which the cosmic microwave background (CMB) observations by the satellite COBE can be used to refute a specific observationally based hypothesis for the global topology (3-manifold) of the Universe is investigated, by a new method of applying the principle of matched circle pairs. Moreover, it is shown that this can be done without assuming Gaussian distributions for the density perturbation spectrum. The Universe is assumed to correspond to a flat Friedmann–Lemaître model with a zero value of the cosmological constant. The 3-manifold is hypothesized to be a 2-torus in two directions, with a third axis larger than the horizon diameter. The positions and lengths of the axes are determined by the relative positions of the galaxy clusters Coma, RX J1347.5-1145 and CL 09104+4109, assumed to be multiple topological images of a single, physical cluster. If the following two assumptions are valid: (i) that the error estimates in the COBE DMR data are accurate estimates of the total random plus systematic error; and (ii) that the temperature fluctuations are dominated by the naıve Sachs–Wolfe effect; then the distribution of the temperature differences between multiply imaged pixels is significantly wider than the uncertainty in the differences, and the candidate is rejected at the 94 per cent level. This result is valid for either the ‘subtracted’ or ‘combined’ Analysed Science Data Sets, for either 10° or 20° smoothing, and is slightly strengthened if suspected contaminated regions from the galactic centre and the Ophiuchus and Orion complexes are removed. [ABSTRACT FROM AUTHOR]

Published
2000
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7. Transverse galaxy velocities from multiple topological images.

Author

Roukema, B.F. and Bajtlik, S.

Subjects
*GALAXIES, *TOPOLOGICAL manifolds
Abstract

The study of the kinematics of galaxies within clusters or groups has the limitation that only one of the three velocity components and only two of the three spatial components of a galaxy position in six-dimensional phase-space can normally be measured. However, if multiple topological images of a cluster exist, then the radial positions and sky plane mean velocities of galaxies in the cluster may also be measurable from photometry of the two cluster images. The vector arithmetic and principles of the analysis are presented. These are demonstrated by assuming the suggested topological identification of the clusters RX J1347.5-1145 and CL 09104+4109 to be correct and deducing the sky-plane relative velocity component along the axis common to both images of this would-be single cluster. Three out of four of the inferred transverse velocities are consistent with those expected in a rich cluster. A control sample of random ‘common’ sky-plane axes, independent of the topological hypothesis, implies that this is not surprising. This shows that while galaxy kinematics are deducible from knowledge of cosmological topology, it is not easy to use them to refute a specific candidate manifold. [ABSTRACT FROM AUTHOR]

Published
1999
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