Bibcode
DOI
Rengstorf, A. W.; Mufson, S. L.; Abad, C.; Adams, B.; Andrews, P.; Bailyn, C.; Baltay, C.; Bongiovanni, A.; Briceño, C.; Bruzual, G.; Coppi, P.; Della Prugna, F.; Emmet, W.; Ferrín, I.; Fuenmayor, F.; Gebhard, M.; Hernández, J.; Honeycutt, R. K.; Magris, G.; Musser, J.; Naranjo, O.; Oemler, A.; Rosenzweig, P.; Sabbey, C. N.; Sánchez, Ge.; Sánchez, Gu.; Schaefer, B.; Schenner, H.; Sinnott, J.; Snyder, J. A.; Sofia, S.; Stock, J.; van Altena, W.; Vivas, A. K.
Bibliographical reference
The Astrophysical Journal, Volume 606, Issue 2, pp. 741-748.
Advertised on:
5
2004
Journal
Citations
22
Refereed citations
19
Description
By observing the high Galactic latitude equatorial sky in drift-scan
mode with the QUEST (Quasar Equatorial Survey Team) Phase 1 camera, we
have collected multibandpass photometry on a large strip of sky,
resolved over a large range of timescales (from hourly to biennially). A
robust method of ensemble photometry reveals those objects within the
scan region that fluctuate in brightness at a statistically significant
level. Subsequent spectroscopic observations of a subset of those
varying objects easily discriminated the quasars from stars. For a 13
month time span, 38% of the previously known quasars within the scan
region were seen to vary in brightness, and subsequent spectroscopic
observation revealed that ~7% of all variable objects in the scan region
are quasars. Increasing the time baseline to 26 months increased the
percentage of previously known quasars that vary to 61% and confirms via
spectroscopy that 7% of the variable objects in the region are quasars.
This reinforces previously published trends and encourages additional
and ongoing synoptic searches for new quasars and their subsequent
analysis. During two spectroscopic observing campaigns, a total of 30
quasars were confirmed, 11 of which are new discoveries and 19 of which
were determined to be previously known. Using the previously cataloged
quasars as a benchmark, we find we can better optimize future
variability surveys. This paper reports on the subset of variable
objects that are spectroscopically confirmed as quasars.