- Ancillary Targets
- Transient Universe in Stripe 82
- Host Galaxies of SDSS-II SNe
- BCGs in
Stripe 82 - High-Quality LRG spectra
- Reddened
Quasars - No Quasar Left Behind
- Variability-Selected Quasars
- K-band Selected Quasars
- Low-Mass Stars and Brown Dwarfs
- Low-Mass Binary Stars
- White Dwarfs and Hot Subdwarfs
- Distant Halo
Giants - Bright
Galaxies - High-Energy Blazars in Optical
- An X-Ray View Star Formation
- Remarkable X-Ray Sources
- Star-Forming Radio Galaxies
- Galaxies Near QSO Sight Lines
- Luminous Blue Galaxies
- BAL Quasar Variability
- Variable QSO Absorption
- Double-Lobed Radio QSOs
- High-Redshift Quasars
- High-z QSOs in SDSS/UKIDSS
- BOSS Targeting
- Algorithms
Bright Galaxies
Summary
A search for bright galaxies that were missed by prior SDSS spectroscopic surveys
Finding Targets
An object whose ANCILLARY_TARGET1
value include one or more of
the bitmasks in the following table was targeted for spectroscopy as part of this ancillary
target program. See SDSS-III bitmasks to learn how
to use these values to identify objects in this ancillary target program.
Program (bit name) |
Bit Number |
---|---|
BRIGHTGAL | 21 |
Description
Bright galaxies were commonly missed in the original SDSS spectroscopic survey due to fiber collisions, bright limits (objects with model magnitudes r >15, g >15, or i >14.5 were excluded), and errors in the deblending of overlapping images (Strauss et al. 2002). Approximately 10% of the brightest galaxies were not spectroscopically observed (Fukugita et al. 2007). To improve the completeness of this spectroscopic sample, we have implemented the selection criteria described below.
Target Selection Details
Objects were chosen with
- Petrosian radius >1" in r (to reject stars)
- No saturated pixels
- Extinction-corrected, Petrosian (Petrosian 1976; Strauss et al. 2002) r magnitude between 10 and 16.
- Extinction-corrected Petrosian magnitude i <20 and z <20 (to exclude misidentified satellite tracks which would not show up in the other bands).
Galaxies without spectra (24,000 from the original list of 93,000) where then visually vetted to remove foreground stars that remained in the sample, detector artifacts (e.g. internal reflections) that were misidentified, and other sources of confusion. In cases where a foreground star was misidentified as the galaxy center, the target position was moved to the correct position. In cases of merging galaxies, we visually identified multiple targets corresponding to the centers of each galaxy. The list was cross-correlated with the Third Reference Catalog of Bright Galaxies (RC3 de Vaucouleurs et al. 1991; Corwin et al. 1994), and any targets that did not appear in the original SDSS spectroscopic survey were added to the target list (0.05% of the final list). Finally, targets within 2'' of a star that appears in the Tycho-2 Catalog (Høg et al. 2000) were removed. The final sample includes 8637 galaxies over the BOSS footprint.
Primary contact
Demitri Muna |
---|
New York University |
demitri.muna -at- nyu.edu |
REFERENCES
Fukugita, M., Nakamura, O., Okamura, S., Yasuda, N., Barentine, J.C., Brinkmann, J.,
Gunn, J.E., Harvanek, M., Ichikawa, T., Lupton, R.H., Schneider, D.P., Strauss, M.A.,
& York, D.G., 2007, AJ, 134, 579
doi:10.1086/518962
Strauss, M. A., Weinberg, D.H., Lupton, R.H., Narayanan, V.K., Annis, J., Bernardi, M.,
Blanton, M., Burles, S., Connolly, A.J., Dalcanton, J., Doi, M., Eisenstein, D.,
Frieman, J.A., Fukugita, M., Gunn, J.E., Ivezić, Ž, Kent, S., Kim, R.S.J.,
Knapp, G.K., Kron, R.G., Munn, J.A., Newberg, H.J., Nichol, R.C., Okamura, S., Quinn, T.R.,
Richmond, M.W., Schlegel, D.J., Shimasaku, K., SubbaRao, M., Szalay, A.S., Vanden Berk, D.,
Vogeley, M.S., Yanny, B., Yasuda, N., York, D.G., & Zehavi, I., 2002, AJ, 124, 1810
doi:10.1086/342343
Petrosian, V., 1976, ApJ, 209, L1
doi:10.1086/182253
Høg, E., Fabricius, C., Makarov, V.V., Urban, S., Corbin, T., Wycoff, G., Bastian, U.,
Schwekendiek, P., Wicenec, A., 2000, A&A, 355, L27,
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