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Kinematics of the Local Universe XIII. 21-Cm Line Kinematics of the Local Universe XIII. 21-cm line measurements of 452 galaxies with the Nançay radiotelescope, JHK Tully-Fisher relation and preliminary maps of the peculiar velocity field Gilles Theureau, Mikko Hanski, Nicole Coudreau, Nicole Hallet, Jean-Michel Martin To cite this version: Gilles Theureau, Mikko Hanski, Nicole Coudreau, Nicole Hallet, Jean-Michel Martin. Kinematics of the Local Universe XIII. 21-cm line measurements of 452 galaxies with the Nançay radiotelescope, JHK Tully-Fisher relation and preliminary maps of the peculiar velocity field. Astronomy and Astrophysics - A&A, EDP Sciences, 2007, 465, pp.71-85. hal-00114730 HAL Id: hal-00114730 https://hal.archives-ouvertes.fr/hal-00114730 Submitted on 17 Nov 2006 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Astronomy & Astrophysics manuscript no. Theureau˙msAA2006˙astroph.hyper24026 c ESO 2006 November 20, 2006 Kinematics of the Local Universe XIII. 21-cm line measurements of 452 galaxies with the Nan¸cay radiotelescope, JHK Tully-Fisher relation and preliminary maps of the peculiar velocity field G. Theureau1,2, M. 0. Hanski1,3, N. Coudreau2, N. Hallet2, and J.-M. Martin2 1 LPCE/CNRS UMR6115, F45071 Orlans Cedex 02, France 2 Observatoire de Paris/Meudon, GEPI/CNRS URA1757, F92195 Meudon Principal Cedex, France 3 Tuorla observatory, University of Turku, SF 21500 Piikki¨o, Finland Received : August 8th, 2006 ; accepted : November 3rd, 2006 ABSTRACT Aims. This paper presents 452 new 21-cm neutral hydrogen line measurements carried out with the FORT receiver of the meridian transit Nan¸cay radiotelescope (NRT) in the period April 2003 – March 2005. Methods. This observational programme is part of a larger project aiming at collecting an exhaustive and magnitude-complete HI extragalactic catalogue for Tully-Fisher applications (the so-called KLUN project, for Kinematics of the Local Universe studies, end in 2008). The whole on-line HI archive of the NRT contains today reduced HI-profiles for 4500 spiral galaxies of ◦ declination δ > 40 (http://klun.obs-nancay.fr). − Results. As an example of application, we use direct Tully-Fisher relation in three (JHK) bands in deriving distances to a large catalog of 3126 spiral galaxies distributed through the whole sky and sampling well the radial velocity range between 0 and − 8 000 km s 1. Thanks to an iterative method accounting for selection bias and smoothing effects, we show as a preliminary output a detailed and original map of the velocity field in the Local Universe. Key words. Astronomical data bases: miscellaneous– Surveys – Galaxies: kinematics and dynamics – Radio lines: galaxies 1. Introduction (DEep Near Infrared Survey, Mamon et al, 2004) and 1 2MASS (2 Micron All Sky Survey, Jarret et al, 2000) near The present paper complements the KLUN data-series (I: infrared CCD surveys. The aim of the programme is to Bottinelli et al. 1992; II: Bottinelli et al. 1993; III: di Nella build a large all sky sample of spiral galaxies, complete et al. 1996, VII: Theureau et al. 1998a, XII: Paturel et al. down to well defined magnitude limits in the five photo- 2003b, Theureau et al. 2005) with a collection of HI line metric bands B, I, J, H and K, and to allow peculiar measurements acquired with the Nan¸cay radiotelescope −1 2 velocity mapping of galaxies up to 10,000 km.s in ra- (FORT) . This programme has received the label of key dial velocity, i.e. up to a scale greater than the largest project of the instrument and is allocated on average 20 structures of the Local Universe. % of observing time since the first light in mid 2000. This programme is complementary to other large HI The input catalogue has been carried out from a com- projects such as HIPASS3 in Parkes (Barnes et al 2001) or hal-00114730, version 1 - 17 Nov 2006 pilation of the HYPERLEDA extragalactic database com- the ALFA-project at ARECIBO4. The majority of the ob- pleted by the 2.7 million galaxy catalogue extracted from jects we observed from Nan¸cay are in the range (-40◦,+0◦) the DSS (Paturel et al. 2000), and the releases of DENIS in declination, thus favouring the declination range un- reachable by ARECIBO. Our aim was to fill the gaps Send offprint requests to: G.Theureau, e-mail: [email protected] left in the last hyperleda HI compilation by Paturel et 1 al. (2003b) in order to reach well defined selection criteria for Kinematics in the Local UNiverse 2 data tables and HI-profiles and corresponding com- in terms of redshift coverage and magnitude completeness ments are available in electronic form at the CDS via (see Sect. 3.). anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html, or directly at our 3 http://www.atnf.csiro.au/research/multibeam/release/ web site http://klun.obs-nancay.fr 4 http://alfa.naic.edu/alfa/ 2 Theureau et al.: Kinematics of the Local Universe XIII This kind of HI data is crucial for constraining the gas and total mass function of spiral galaxies as a function of morphology and environnement, it allows also the map- ping of the total mass distribution from peculiar veloci- ties and thus provides strong constraints on cosmological models and large scale structure formation. They can in particular provide a unique starting point for total mass power spectrum studies. Study of peculiar velocities allows the verification of the current theory of cosmological structure formation by gravitational instability. It gives information on bulk mo- tion, and the value of Ωm (cf. reviews by Willick 2000 and Zaroubi 2002, and the comprehensive work by Strauss & Willick 1995). The velocity measurements are done using redshift independent secondary distance indicators, such as the Tully-Fisher (TF) relation for spiral galaxies, the Faber-Jackson, Dn-σ, Fundamental Plane (FP) relation, or the surface brightness fluctuations for early type galax- ies. The largest surveys so far are the Mathewson and Ford 1996 sample, the MARK III (Willick et al. 1997), SFI (Giovanelli et al. 1997, Haynes et al. 1999), ENEAR (da Costa et al. 2000a,2000b), and the updated FGC cat- alogue (2MFGC, Mitronova et al. 2004). Each contains in the order of one or two thousand independent distance es- timates in the local 80 h−1 Mpc volume. The use is then to compare them to the velocity field derived from the galaxy density distribution as infered from complete red- shift sample (e.g. PSCz, Saunders et al. 2000, or NOG, Marinoni et al. 1998) Our own Kinematics of the Local Universe (KLUN) TF sample has been used in the study of H0 (Theureau et al. 1997, Ekholm et al. 1999) and local structures (Hanski et al. 2001). The sample consists of all the galax- ies with published rotational velocities collected in the HYPERLEDA5, database (Paturel et al. 2003a), plus the recent large KLUN+ contribution (Theureau et al Fig. 1. Aitoff projection of the observed sample in J2000 2005 and this paper). The total Tully-Fisher sample equatorial coordinates, histogram of radial velocities V20 counts 15 700 spirals and uses five different wavelength and HI fluxes (see Table 2) galaxy magnitudes. B- and I-magnitudes come from vari- ous sources, carefully homogenized to a common system. The largest sources are DSS1 for B, and Mathewson et method to obtain unbiased peculiar velocities from it is al. (1992, 1996) and DENIS (Paturel et al. 2004) for I given in Sect. 4; finally, we give in Sect. 5 some prelimi- band. J, H, and K-magnitudes are from the 2MASS6 sur- nary results and show some examples of peculiar velocity vey (Jarret et al. 2000). The 2MASS magnitudes, taken map realization. from a single survey, avoid any problems that the homog- enization may cause, and are thus exclusively used in data analysis. Further, we exclude the measurements with large 2. The HI data errors and the galaxies that for other reasons, explained 2.1. The Nan¸cay observations later in the text, are unsuitable for this study. 3126 galax- ies remain, which we use for the mapping of the peculiar The Nan¸cay radiotelescope (France) is a single dish an- −1 tenna with a collecting area of 6912 m2 (200 34.56) velocity field within the radius of 80 h Mpc. × The paper is structured as follows: the Nan¸cay radiote- equivalent to that of a 94 m-diameter parabolic dish. The lescope, the processing chain and the reduced HI data are half-power beam width at 21-cm is 3.6 arcmin (EW) 22 arcmin (NS) (at zero declination). The minimal system× presented in Sect. 2; The characteristics of the input Tully- ◦ Fisher catalogue are listed in Sect. 3, while the iterative temperature at δ = 15 is about 35 K in both horizontal and vertical polarizations. The spectrometer is a 8192- 5 http://leda.univ-lyon1.fr channel autocorrelator offering a maximal bandwidth of 6 http://www.ipac.caltech.edu/2mass/ 50 MHz. In this mode, and with two banks in vertical and Theureau et al.: Kinematics of the Local Universe XIII 3 horizontal polarizations counting 4096 channels each, the pilation of line widths by Springob et al. 2005. The over- spacing of the channels corresponds to 2.6 km.s−1 at 21 lap is quite small, concerning 20 galaxies only.
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