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ON THE ORIGIN OF LARGE SCALE STRUCTURES. Piotr Flin. Włodzimierz Godłowski Elena Panko. Instytut Fizyki, Uniwersytet Jana Kochanowskiego, Kielce, Polska Instytut Fizyki, Uniwersytet Opolski, Opole, Polska Kalinenkov Astronomical Observatory, Nikolaev, Ukraine. Outlook.
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ON THE ORIGIN OF LARGE SCALE STRUCTURES Piotr Flin Włodzimierz Godłowski Elena Panko Instytut Fizyki, Uniwersytet Jana Kochanowskiego, Kielce, Polska Instytut Fizyki, Uniwersytet Opolski, Opole, Polska Kalinenkov Astronomical Observatory, Nikolaev, Ukraine
Outlook • A fewhistoricalremarks • Observations • Numericalsimulations • Applied observational data: • Twosets: • LSC: Tully’s group w LSC • Strukturescatalogue PF • Structureshape • Superclusters • Binggelieffect • PF structures • NBG groups • Conclusions
Large scale distribution of matter in the Universe(cosmic web) long structures (filaments) flat structures (sheets, walls) dense, compact regions (galaxy clusters ) surrounded by depopulated regions (voids)
LSC GF ApJ 70,.920 (2010)
Consideredmodel • HOT BIG BANG • EKSPANSION OF THE UNIVERSE 106 YAERS AFTER THE BIG bANG Temperature of matter and radiations ~3*103 K:primivalplasmarecombination freeelectronsdisappeared, drasticreduction of theradiation and matterinteractions, • Independent evolution of radiation and matter. • TheUniversebecames transparent
Kind of matter: Barionic non barionic, what is the distribution of both ? HOT : lekkie ( ~100 eV) i relatywistyczne aż do rekombinacji cząstki ( neutrino) WARM (1 – 10 keV) stają się nie- relatywistyczne wcześniej COLD ciężkie cząstki, która bardzo wcześnie przestają byćrelatywistyczne Mają bardzo małe prędkości Gravitinos, photinos, axions (WIMP)
Parametersconectedwithdensityperturbations • Type of perturbation • Amplitude • Skale of perturbation(MASS orthescalelenght TREE MAIN TYPES OF FLUKTUATIONS: • ADIABATIC (RADIATION AND MATTER ARE PERTURBED ), (ENTROPIA PER BARION IS CONSTANT) • ISOTERMIC PERTURBACJE (TEMPERATURE AND RADIATION DENSITY = CONST, ONLY MATTER FORMS AGGREGATIONS) 3. TURBULENCES (EDGGES) - (BOTH MATTER AND RADIATION) Varioussceneriosstructureoriginpredictsdiferentproerties of structures: mainlyshape and theacquitance of angularmomenta of galaxies. modele : top – down, bottom – up
Explosivescenario Wiele małych eksplozji równocześnie 25 – 50 Mpc 1065 erg lub Nadprzewodzące struny kosmiczne Młode galaktyki, kwazary do 5 Mpc 1061 erg
Turbulences • Pancake • Hierarchicalclustering (tidaltorquing) Iye & Sugai, 1991ApJ 374, 12
Observational data • FromTully’sCatalogue: • 61 galaxygroups • 26 groupswith10 - 20 objects • 35 >20 objects • Positionangle of the group PAg • Positionangle of thelinejoining 2 brightestgalaxiesPAl • Positionangleof the BCM PAbm • DirectiontowardVigo ClustercentrePAV • Isotropytested(K-S, c2 )
The distribution of the acuteangle Θ between the position angle of the major axis of a given group (PAg) and direction towards other groups. From top to bottom the distributions for galaxies with D 10 Mpc, 10<D20 Mpc, 10<D20 Mpc and D>20 Mpc are presentedrespectively.
The distribution (from top to bottom) of the differences between position angles (PAg-PAV, PAl-PAV, PAg-PAl).
The distribution (from top to bottom) of the position angle of the major axis of a given group (PAg), the position of the line joining two brightest galaxies in the group (PAl) and direction towards Virgo cluster (PAV).
Twobrightestoriginated on thefilamentdirectedtowardthecentre of of LSC. Throughthegravitationalinteractiongalaxygroupsareformed on thelineconectedthesetwobrightestgalaxies. Therefore we observedaligment of structure and lineconnectingtwobrightes
Thisispictureshowingtheorigininthecase of not verymassivesytucture, as LSC. Itisinteresting to lookingreaterscale and in 2D. Thereare not statisticallycomplete data for such a task. Therefore, we decided to checktheobservedtendency. We will usethe PF Catalogue .
Observational data • The Muenster Red Sky Survey is a large-sky galaxy catalogue covering an area of about 5000 square degrees on the southern hemisphere. The catalogue includes 5.5 millions galaxies and is complete till photo-graphic magnitude rF=18m.3(Ungruhe 2003). • 217 ESO Southern Sky Atlas R Schmidt plates with galactic latitudes b<-45 were digitized with the two PDS microdensitometers of the Astronomisches Institut at Muenster. The classification of objects into stars, galaxies and perturbed objects was done with an automatic procedure with a posterior visual check of the automatic classification. The external calibration of the photographic magnitudes was carried out by means of CCD sequences obtained with three telescopes in Chile and South Africa. The MRSS contains positions, red magnitudes, radii, ellipticities and position angles of about 5.5 million galaxies and it is complete down to rF=18m.3.
Distribution of galaxies of Muenster Red Sky Survey. Blue color indicates low galaxy densities, green and yellow high galaxy densities. White spot is the region around the SMC.
Structurefinding • We selected the Voronoi tessellation technique (VTT hereafter)for cluster detection. • This technique is completely non-parametric, and therefore sensitive to both symmetric and elongated clusters, allowingcorrect studies of non-spherically symmetric structures. For adistribution of seeds, the VTT creates polygonal cellscontainingone seed each and enclosing the whole area closest to the seed.This is the definition of aVoronoi cell in 2D.
Structures PF 0364-3272 and PF 2243-4774 in tangential coordinates, north is up. Open dots represented the structure members, black symbols corresponded to brightest galaxy in cluster, and line notes the direction of fitted ellipse major axe. Ellipticityand major axis position angle are shown in the right corner for each structure. PJF 2009, AJ 138, 1709
Using standard covariance ellipse method for galaxies in the considered region within the magnitude limit m3, m3+3m, we determined the moments of the distribution: The semiaxes in arcsec for the best-fitting ellipse were calculated from: Ellipticity: Positionangle:
Voronoi cells for PF 2243-4774 region (left panel) and the found cluster members as black dots with non-clustered galaxies as open symbols (right panel). PJF 2009, AJ 138, 1709
Struktury PF 6188 struktur przedział jasności: m3 – m3+3m
Results: veryrichsuperclusters : Superclusters n=8 n>4 Angle P random 0.647 0.750 0.524 Angle deltad: anisotropy 0.150 0.250 0.238 0.250 Angle etah: anisotropy 0.227 0.3000 0.190 0.300 In veryrichclustersanlignmentshould be thegreatest, iforientationioriginatedsimultulanouslywithprotostrcutures.. Anisotropyisincreasingwithstructuresize ( mass). Theincrease of anizotropii withrichness was observedinthecase of rich ( n>100) structures PF. Herethe same patternisconfirmed.utaj jest potwierdzony.
Conclusions: Galaxygroupsformed first, nexttheymergedue to hierarchicalclustering and formedgreaterstructures. Theprotomainplane of theprotostructureforms, whichattractsothergroups. Thereforestructuresareflat. Thistendencyisobservedinthecase of 1D i 2D structur.es Of course, thisispreliminaryresults, whichshould be confirm on much bettterstatisticalsample.
Orientation of the galaxy groups in the Local Supercluster Piotr Flin, Włodzimierz Godłowski Institute of Physics, Jan Kochanowski University, Kielce, Poland Institute of Physics, Opole University, Opole, Poland
Recent dynamical evolution Plionis (2002)
The distribution of estimated z and the limits of the division into groups BFJP 2009, ApJ 696, 1689