Propuesta: GS-2005A-Q-66
(propuesta conjunta con UK)
Investigador Principal: Dr Luis
Campusano (U.Ch)
Título: The Galaxy Population
Around a Possibly Forming Cluster at z~1.2
Resumen:
The largest large-scale structures
(super-LSSs, SLSSs) provide essential tests for models
of structure formation and allow the very efficient
study of large numbers of galaxies, clusters and other
mass markers such as quasars. The epoch z~1 has emerged
as "special" for the evolution of galaxies, as indicated
by the peak in the star formation rate and by the close
peak in the space density of AGNs. Also, hierarchical
formation models predict that z~1 is the major epoch
for galaxy-cluster assembly. We have identified two
"parallel" >~ 20-30 Mpc-scale structures at z~0.8
and z~1.2 (Haines, Campusano & Clowes, 2004), towards
which we wish to direct a GMOS FOV pencil beam. The
beam will be centered on a z~1.2 cluster-pair (J104656.6
+054150), which is likely to be a merger in progress.
Specifically, we propose complete spectroscopic follow-up
of all the galaxies with I-K>3.0 and to K=19.5 within
a 5'x5' field (~4x4 Mpc^2 at z=1.2). This will allow
us to: (1) measure spectroscopic redshifts of 140 galaxies
belonging mainly to the SLSS at z~1.2 but also including
galaxies of the z~0.8 SLSS; (2) estimate the mass of
the z~1.2 cluster and test the merger hypothesis; (3)
characterise the environment of the z=1.233 quasar (J104420.8
+055739), which is at the confluence of the two subclusters
of J104656.6 +054150; (4) determine trends at z~1.2
between star-formation rate (SFR) in galaxies and environment;
and (5) estimate the epoch at which cluster environment
begins to affect star formation in galaxies.
Tiempo asignado:
21.0 horas
_____________________________________________________________________________________
Propuesta: GS-2005A-Q-74
Investigador Principal: Dr Marcus
Albrecht (UCN)
Título: First 3D spectroscopy
of type-2 quasar narrow-line regions: Size, structure,
and kinematics
Resumen:
We recently investigated
the NLR of seven type-1 PG quasars with HST and found
a size-luminosity relation for Seyferts and quasars
which is of great interest as an independent black hole
mass estimator. Now, a decent sample of SDSS type-2
quasar candidates is available allowing us to extend
this study into largely unknown territory. The nature
of type-2 quasars is still strongly debated: Are they
subject to a simple inclination-based unified scheme
with ionization cones as found for some Seyfert 2s?
What determines the size of a quasar-2 NLR and how does
it scale with luminosity? What can we learn from NLR
sizes about quasar lifetimes? What is the origin of
the NLR gas and how relevant are mergers for quasar
fueling? To answer these questions, we propose to use
GMOS/IFU to obtain the first 3D spectroscopy of quasar
NLR as traced by the [OIII] and Hbeta lines in a pilot
study of three bright type-2 quasar candidates from
the SDSS.
Tiempo asignado:
9.2 horas
_____________________________________________________________________________________
Propuesta: GS-2005A-C-4
Investigador Principal: Dr Daniel
Christlein (UCh)
Título: Extent and Kinematics
of the Extreme Outer Disks of Spiral Galaxies
Resumen:
The kinematics of gas on the
extreme outskirts of galaxies provide unique constraints
on the halo mass profile and the angular momentum distribution
of the baryonic matter, both important outstanding questions
in galaxy formation. However, the true outer edges of
galaxy disks are inaccessible to conventional observational
techniques, because optical line emission is extremely
faint, and the outer parts of the baryonic disk are
ionized and thus invisible in the 21 cm line. A novel
probe of galaxy kinematics is to observe H-alpha emission
at extremely large radii, caused by ionization by isolated
star formation regions, nearby UV sources, or the cosmic
background.
Here, we propose to extend
our successful efforts to detect H-alpha emission from
the outer disks of late-type edge-on spiral galaxies
using extremely deep long-slit spectroscopy. This project
will pursue four goals: place new lower bounds on the
radii of the disks, measure the rotation curve at unprecedented
radii, provide spectroscopic information on possible
star formation in an environment of low density and
low metallicity, and provide constraints on the strength
of the ionizing cosmic background radiation field at
low redshifts.
Tiempo asignado:
30.0 horas
___________________________________________________________________________________
Propuesta: GS-2005A-C-6
(propuesta conjunta con BR)
Investigador Principal: Dra. Manuela
Zoccali (PUC)
Título: Chemical abundances
in metal-poor globular clusters of the Galactic bulge
Resumen:
The Galactic bulge is the least
studied stellar population in our Galaxy. Very little
data is available in terms of its detailed abundance
pattern which could give important information of the
formation and chemical enrichment of the bulge. In the
framework of hierarchical clustering, it is predicted
that the metal-poor bulge stars and globular clusters
were among the very first objects which formed. We intend
to observe 10 red giants in the metal-poor bulge globular
clusters HP-1 and NGC 6558 using the Phoenix IR spectrograph.
We have V and I colours obtained for these clusters
with the NTT telescope, and also ESO Wide-Field photometry
for NGC 6558. For one star of HP-1 and 4 stars of NGC
6558 we have obtained and analysed high resolution spectra
obtained in the optical using VLT-UVES, and VLT-Flames.
The IR is ideal for the purpose given the low impact
of reddening and the small amount of line-crowding in
the stellar spectra, which allow the measurement of
very accurate element abundances. The very scarce abundance
information available for metal-poor bulge stars to
date suggest significant differences with the halo population
of similar metallicity for unknown reasons, which we
intend to investigate. The proposed observations will
enable the determination of the abundances of oxygen
using the OH lines, that is the main purpose of this
proposal, besides C, N, Fe and the alpha-element Ti,
which will provide important insight to the nucleosynthetic
enrichment during the earliest phases of our Galaxy.
Tiempo asignado:
5.0 horas
