Survey Integrity, Quality and Archiving Issues

1
Survey Integrity, Quality and Archiving Issues

• Rachel Campbell
• and
• Quentin Parker

2
Overview

• Current state of the archive
• Stars with repeat observations
• Fibre Statistics
• Data Quality Issues
• Double star contamination
• Bright stars in adjacent fibres
• Problematic Fields
• Survey Integrity

3
RAVE Data Archive Structure

• RAVE archive can be found at
• www2.aao.gov.au/RAVE/
• username rave
• password rave_review
• Directory is complete to 8th February
• 2006
• 1173 fields available

4
RAVE Data Archive Structure
0909m031I003.fits.gz 1029m240I019.fits.gz 1231m341
I029.fits.gz 1418m304I039.fits.gz
20030411
2003
2004
ARC
20031215
2005
calibration_data
FLAT
2006
SKY
0909m03.tar.gz 1029m24.tar.gz 1231m34.tar.gz 1418m
30.tar.gz
20030411
2003
raw_data
2004
20031215
2005
2006
0909m031Ired.sdf.gz 1029m240Ired.sdf.gz 1231m341Ir
ed.sdf.gz 1418m304Ired.sdf.gz
20030411
2003
reduced_data
20031215
2006
5
Repeated RAVE Stars

• Stars have repeated observations when the
  entire field is repeated with the same
  configuration
• Currently of the 5854 repeated stars
• 5360 have been observed two times
• 396 have been observed three times
• 4 have been observed four times
• 94 have been observed six times

6
Field Plate Status
7
Field Plate
8
Field Plate Status
Ave 1.8 breaks/fibre
Ave 2.0 breaks/fibre
9
Plate Footprint
Plate 1
10
Plate Footprint
Plate 2
11
Plate Footprint
Plate 2 Oxford Algorithm
Brent Miszalski, 2006
12
Plate Footprint
Plate 2 Simulated Annealing
Brent Miszalski, 2006
13
Double Star Contamination
Some stars from both catalogues used to create
RAVEs target list are misidentified double stars
Tycho Stars

• 200 observed fields were checked and 87 blended
  objects were found.
• Results in RAVE data comprising 0.4 double stars

UKST Stars
14
Adjacent Fibre Contamination

• As we observed for the first three years without
  magnitude limiting the configured stars, light
  from a bright star in a neighbouring fibre can
  contaminate a faint star
• If we assume that the overlap in flux is 4, what
  fraction of stars will be severely affected?

15
Adjacent Fibre Contamination
16
Problematic Fields

• Missing/wrong calibration data
• Severe cloud/moonlight in all frames
• Poor seeing in all frames
• Neon lines missing from edge of arc
• Slit-vane shift due to camera shutter
• Poor Focus
• Failed to be reduced by ravedr
• Failed to be reduced by IRAF pipeline

17
Data Integrity
18
Data Quality

• Several problems with the RAVE data have already
  been identified
• Plate holder issues
• Fibre attrition rate
• Fringing
• Fibre S/N as a function of fibre number
• Scattered light contamination
• Shifts in focus
• Fibre-Fibre cross-talk

19
Data Quality

• Several problems with the RAVE data have already
  been identified
• Plate holder issues
• Fibre attrition rate
• Fringing
• Fibre S/N as a function of fibre number
• Scattered light contamination
• Shifts in focus
• Fibre-Fibre cross-talk
• Currently analysing these problems

20
Fibre Behaviour

• With more than 2 years of data, the response of
  fibres over time can now be quantified in order
  to
• Flag fibres which are behaving erratically so
  that they can be mended/replaced as necessary
• Search for seasonal and operational changes in
  fibre transmission, variability and rate of
  fracture
• Measure the response of the spectrograph to red
  and blue light as a function of fibre number

21
Fibre Behaviour
22
Fibre Behaviour
Mean
Days since 1st Jan 02