7,411 research outputs found
Large-Scale Structures Behind the Southern Milky Way from Observations of Partially Obscured Galaxies
We report here on extragalactic large-scale structures uncovered by a deep
optical survey for galaxies behind the southern Milky Way. Systematic visual
inspection of the ESO/SRC-survey revealed over 10000 previously unknown
galaxies in the region 265 < l < 340, |b| < 10. With subsequently obtained
redshifts of more than 10% of these galaxies, new structures across the Milky
Way are unveiled, such as a filament at ~ 2500 km/s connecting to the Hydra
and Antlia clusters, a shallow extended supercluster in Vela (~ 6000km/s), and
a nearby (4882 km/s), very massive (M ~ 2-5 10^15 Msun), rich Coma-like cluster
which seems to constitute the previously unidentified center of the Great
Attractor. The innermost part of the Milky Way where the foreground obscuration
in the blue is 5mag, respectively HI-column densities greater than 6 10^21 /
cm^2 remains fully opaque. In this approximately 8 degrees wide strip, the
forthcoming blind HI-survey with the multi-beam system at Parkes will provide
the only tool to unveil this part of the extragalactic sky.Comment: Presented at the Multibeam Workshop on ``HI in the Local Universe'',
Sydney, May 13-15 1996. Accepted 2.11.1996 for publication by PASA.
Latex-file with 4 encapsulated postscript files. Version with original
figures available at
http://www.atnf.csiro.au/~lstavele/13beam/proceedings/korteweg/korteweg.htm
The SED of the nearby HI-massive LIRG HIZOA J0836-43: from the NIR to the radio domain
HIZOA J0836-43is one of the most HI-massive galaxies in the local (z<0.1)
Universe. Not only are such galaxies extremely rare, but this "coelacanth"
galaxy exhibits characteristics -- in particular its active, inside-out stellar
disk-building -- that appear more typical of past (z ~ 1) star formation, when
large gas fractions were more common. Unlike most local giant HI galaxies, it
is actively star forming. Moreover, the strong infrared emission is not induced
by a merger event or AGN, as is commonly found in other local LIRGs. The galaxy
is suggestive of a scaled-up version of local spiral galaxies; its extended
star formation activity likely being fueled by its large gas reservoir and, as
such, can aid our understanding of star formation in systems expected to
dominate at higher redshifts. The multi-wavelength imaging and spectroscopic
observations that have led to these deductions will be presented. These include
NIR (J H K) and MIR (Spitzer; 3-24micron) imaging and photometry, MIR
spectroscopy, ATCA HI-interferometry and Mopra CO line emission observations.
But no optical data, as the galaxy is heavily obscured due to its location in
Vela behind the Milky Way.Comment: 5 pages, 3 figures, to appear in the proceedings of IAU Symposium
284, "The Spectral Energy Distribution of Galaxies" (SED2011), 5-9 September
2011, Preston, UK, editors R.J. Tuffs & C.C.Popesc
Stop and sbottom searches at LEP
This talk reviews the searches for sbottom and stop quarks at LEP. The
existing results of the four LEP experiments for sbottom and stop quarks
searches are summarized. Furthermore, new mass limits on stable hadronizing
squarks and gluinos are derived by combining Z-lineshape constraints with
direct searches for squarks and gluinos using ALEPH data. All limits are
derived in the framework of R-parity conserving models.Comment: 4 pages, 7 figures. To appear in proceedings XXXVIIIth Rencontres de
Moriond: Electroweak Interactions and Unified Theories, Les Arcs, France,
March 200
SUSY Searches at LEP
Searches for SUSY particles have been performed in 3.6 fb ee
data collected by the LEP detectors at between 90 GeV and 209 GeV.
This talk reviews some of the relevant searches for SUSY particles at LEP. No
excess of events is observed in any channel. Results are interpreted in the
context of the MSSM.Comment: 5 pages, 9 figures, conference contribution to Lake Louise Winter
Institute 200
Measurements of top quark properties at CDF
The top quark with its mass of about 172 GeV/c^2 is the most massive
fundamental particle observed by experiment. In this talk we highlight the most
recent measurements of several top quark properties performed with the CDF
detector based on data samples corresponding to integrated luminosities up to 1
fb-1. These results include a search for top quark pair production via new
massive resonances, measurements of the helicity of the W boson from top-quark
decay, and a direct limit on the lifetime of the top quark.Comment: Proceedings for ICHEP 2006 (Jul 26 - Aug 2), Moscow, Russi
An Overview of Uncovered and Suspected Large-Scale Structures behind the Milky Way
Various dynamically important extragalactic large-scale structures in the
local Universe lie behind the Milky Way. Most of these structures (predicted
and unexpected) have only recently been made ``visible'' through dedicated deep
surveys at various wavelengths. The wide range of observational searches
(optical, near infrared, far infrared, radio and X-ray) for galaxies in the
Zone of Avoidance (ZOA) will be reviewed and the uncovered and suspected
large-scale structures summarised. Particular emphasis is given to the Great
Attractor region where the existence of yet another cluster is suspected (Woudt
1998). Predictions from reconstructions of the density field in the ZOA are
discussed and compared with observational evidence. Although no major
structures are predicted out to about v < 10000 km/s for which no observational
evidence exists, the comparison between reconstructed density fields and the
observed galaxy distribution remain important as they allow derivations of the
density and biasing parameters.Comment: To appear in PASA 16. Proceedings of workshop "HI in the Local
Universe, II", held in Melbourne, Sept. 1998. 9 pages, LaTeX2e, 1
encapsulated PS figur
DENIS Observations of Multibeam Galaxies in the Zone of Avoidance
Roughly 25% of the optical extragalactic sky is obscured by the dust and
stars of our Milky Way. Dynamically important structures might still lie hidden
in this zone. Various surveys are presently being employed to uncover the
galaxy distribution in the Zone of Avoidance (ZOA) but all suffer from
(different) limitations and selection effects.
We illustrate the promise of using a multi-wavelength approach for
extragalactic large-scale studies behind the ZOA, i.e. a combination of three
surveys -- optical, systematic blind HI and near-infrared (NIR), which will
allow the mapping of the peculiar velocity field in the ZOA through the NIR
Tully-Fisher relation. In particular, we present here the results of
cross-identifying HI-detected galaxies with the DENIS NIR survey, and the use
of NIR colours to determine foreground extinctions.Comment: Accepted for publication in PASA. Proceedings of workshop "HI in the
Local Universe, II", held in Melbourne, Sept. 1998. 9 pages, LaTeX2e, 2
encapsulated PS figures, 3 JPEG figures, Full resolution figures 2, 3 and 4
and full resolution paper are at
ftp://ftp.iap.fr/pub/from_users/gam/PAPERS/HICONF
Extragalactic Large-Scale Structures behind the Southern Milky Way. IV. Redshifts Obtained with MEFOS
Abbreviated: As part of our efforts to unveil extragalactic large-scale
structures behind the southern Milky Way, we here present redshifts for 764
galaxies in the Hydra/Antlia, Crux and Great Attractor region (266deg < l <
338deg, |b| < 10deg), obtained with the Meudon-ESO Fibre Object Spectrograph
(MEFOS) at the 3.6-m telescope of ESO. The observations are part of a redshift
survey of partially obscured galaxies recorded in the course of a deep optical
galaxy search behind the southern Milky Way. A total of 947 galaxies have been
observed, a small percentage of the spectra (N=109, 11.5%) were contaminated by
foreground stars, and 74 galaxies (7.8%) were too faint to allow a reliable
redshift determination. With MEFOS we obtained spectra down to the faintest
galaxies of our optical galaxy survey, and hence probe large-scale structures
out to larger distances (v <~ 30000 km/s) than our other redshift follow-ups.
The most distinct large-scale structures revealed in the southern Zone of
Avoidance are discussed in context to known structures adjacent to the Milky
Way.Comment: 11 pages, 7 figures; accepted for publication in A&A. Tables 1 and 2
will be available in electronic format at the CDS. Figure 1 at full
resolution, and both tables are available at
http://mensa.ast.uct.ac.za/~pwoudt/data/H4462/
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