Hit RELOAD to update list
CTIO, Apr 1-6 2000
The transient detection strategy for our current run
is optimized to detect stationary transients. Previous runs were
performed without the advantage of having long time baselines, hence we
posted many moving objects. We now
have, for many of our fields, 1 month baselines, and we are currently
co-adding 5 exposures together to detect dim, stationary transients such
as SN and other bursting phenomena.
This page contains REAL-TIME information on detections of
transient astronomical happenings from the
Deep Lens Survey, currently
being undertaken on the KPNO and CTIO 4-m telescopes using the
wide-field MOSAIC imagers.
A by-product of this wide-field survey is the detection of
transient astronomical phenomena, including Near Earth Objects (NEO),
Kupier Belt Objects (KBO), Supernova (SN), and even previously unknown
events which happen with such rarity that only a wide field and deep
survey, such as this one, is even reasonably sensitive to them.
The table below contains recently updated information on objects
detected during the course of this survey. These are extracted from
the images in real-time using a combination of SExtractor
for object detection and ISIS to provide
differenced images, from which we are able to identify transient, or
"new", objects, after filtering out spurious objects like cosmic rays.
These objects have also been inspected by eye and categorized as probably real.
We include the date, DATE-ARCH, when the object was added to this
archive or updated, the date the object was most recently observed
DATE-OBS (MJD),
and the FILTER of this observation. Additionally, we include
the RA and DEC (J2000, to ~0.5'' accuracy) of the object, a preliminary
categorization of the nature of the transient, and
a preliminary estimate of the magnitude of the transient (+/-
0.1 mag in R and B, +/- 0.5 in V and z). Two types of images are
available for download: mosaics and finding charts.
The mosaic page includes a time-series of GIFs showing 200-pixel (50") postage
stamps, with time increasing from top to bottom. The discovery mosic
includes a template observation on the left,
discovery image in the middle, and difference image on the right.
Subsequent mosaics show a similar collection of images, or the
new observation image only, in the case where a subtraction image was not available.
The files are generally a
few hundred kilobytes. In all mosaics, East is up and North is to the right.
The finding charts are 5'x5' FITS images centered on the discovery
position. The time in the header is the start of the exposure and the
world coordinate system in the header is accurate to 0.5". The files
are 3 MB. The images are zero-padded to maintain the object in the
center even if it was near the edge of the discovery image. Your
browser may not bring up saoimage/ximtool automatically on the FITS
file. Right-click on the link to save to local disk.
For moving objects, a finding chart is useless, and instead we provide an
ASCII list of positions and times.
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