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تسجيل مستخدم جديدThe Nancay HI Zone of Avoidance survey of 2MASS bright galaxies
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To complement the 2MASS Redshift Survey (2MRS) and the 2MASS Tully-Fisher survey (2MTF) a search for 21cm HI line emission of 2MASS bright galaxy candidates has been pursued along the dust-obscured plane of the Milky Way with the 100m Nancay Radio Telescope. For our sample selection we adopted an isophotal extinction-corrected K-band magnitude limit of $K_s^o = 11.25$mag, corresponding to the first 2MRS data release and 2MTF, for which the 2MASX completeness level remains fairly constant deep into the Zone of Avoidance (ZoA). About one thousand galaxies without prior redshift measurement accessible from Nancay (Dec > -40deg) were observed to an rms noise level of ~3 mJy for the velocity range -250 to 10600 km/s. This resulted in 220 clear and 12 marginal detections of the target sample. Only few detections have redshifts above 8000 km/s due to recurring radio frequency interference (RFI). A further 29 detections and 6 marginals have their origin in non-target galaxies in the telescope beam. The newly detected galaxies are on average considerably more HI-rich (mostly $10^9 - 10^{10}$M$_odot$) compared to systematic (blind) HI surveys. The HI detections reveal various new filaments crossing the mostly uncharted northern ZoA (e.g. at $ell sim 90deg, 130deg, 160deg$), whilst consolidating galaxy agglomerations in Monoceros and Puppis ($ell sim 220deg, 240deg$). Considerably new insight has been gained about the extent of the Perseus-Pisces Supercluster through the confirmation of a ridge ($ell sim 160deg$) encompassing the 3C129 cluster that links Perseus-Pisces to Lynx, and the continuation of the second Perseus-Pisces arm ($ell sim 90deg$) across the ZoA.
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A blind HI survey of the extragalactic sky behind the southern Milky Way has been conducted with the multibeam receiver on the 64-m Parkes radio telescope. The survey covers the Galactic longitude range 212 < l < 36 and Galactic latitudes |b| < 5, an
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We present a catalogue of galaxies in the northern Zone of Avoidance (ZoA), extracted from the shallow version of the blind HI survey with the Effelsberg 100 m radio telescope, EBHIS, that has a sensitivity of 23 mJy/beam at 10.24 km/s velocity resol
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