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SIRTF at AAS - Albuquerque, NM, June 2-6, 2002
The 200th meeting of the American
Astronomical Society (AAS) was held in Albuquerque, NM on June 2-6,
2002. The following posters featured SIRTF or the research of SIRTF team
members:
The Reddest Quasars -- Further Observations of the "Red
Menace"
M. Lacy (SSC), M.D. Gregg, R.H. Becker (IGPP/LLNL, UC Davis), R.L.
White (STScI), E. Glickman, D. Helfand (Columbia)
We present the latest results of our program to find luminous,
dust-reddened quasars through matching the FIRST radio survey with the
2MASS near-infrared survey. We show Keck/ESI optical and IRTF/SpeX spectra
of our objects, and briefly discuss new Chandra data on a few of our
sources. 2/13 of our red quasars are lensed (including the first known
lensed FeLoBAL quasar). Simple calculations suggest that these objects may
consistute a significant population impossible to find in optical bands at
high redshifts. We use these findings to briefly discuss the nature and
numbers of red quasars in the context of the general quasar population.
Identifying Moderate Redshift Damped Lyman-alpha Galaxies
L. J. Storrie-Lombardi (SSC), M. Lacy (SSC), R.H. Becker (IGPP/LLNL,
U.C. Davis)
We present here preliminary results from a survey of quasar fields with
damped Lyman-alpha absorption systems (DLA) in the redshift range 0.6 <
z < 2. This is a program to identify new DLA absorbers with z < 2
and understand the nature of the galaxies responsible for the absorption
and their contribution to the comoving mass density in neutral gas at
moderate redshifts. NIRC K' imaging is combined with LRIS spectroscopy of
the candidate galaxies detected in the field and an HST program to
identify the Lyman-alpha absorption based on the strength of MgII seen in
the optical quasar spectra.
On the Relationship Between Stellar Rotation and Radius in Young
Clusters
L. M. Rebull (SSC), S. C. Wolff (NOAO), S. E. Strom (NOAO), R. B.
Makidon (STScI)
We have compiled data on rotational velocities for more than 1000 K &
M stars in 12 young clusters ranging in age from Orion to the Hyades.
These data enable a search for systematic changes in stellar rotational
velocity vs. age. Taken together, these data show that most PMS stars
spanning ages ~0.1-~10 Myr do not appear to spin up in response to
contraction down their convective tracks, and further suggest that any
spin up between 10 Myr and the ZAMS is modest (<2x) at best.
These results extend and reinforce our earlier study (Rebull et al. 2002),
based on observations of several hundred stars in the Orion Flanking
Fields, NGC 2264, and the Orion Nebula Cluster (ONC), which showed that
the majority of PMS stars in these three groups apparently do not conserve
stellar angular momentum as they contract, but instead evolve at nearly
constant angular velocity. This result applies both to stars with and
without near-IR (I-K) excesses indicative of disks.
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