Evaluation of 6 d F Data Lesa Moore

Evaluation of 6 d. F Data Lesa Moore Macquarie University Honours Project 2003 Supervisor: Quentin Parker MU/AAO

Goals of Honours Project n n n Independent evaluation of results from 6 d. FDR and RUNZ Comparison analysis using IRAF dofibers, line measurements, xcsao and emsao Test 6 d. FDR and RUNZ for accuracy and systematic errors by comparison with IRAF results Test 6 d. FDR and RUNZ for repeatability Report to survey team with results and recommendations 2

Target and Observed Fields One field studied to date My first field!! 3

Field Details 0924 m 30 n Observed 20/3/2002 n Reflection gratings 600 V: 4000 -5600Å; 316 R: 5500 -8500Å n 109 spectra, 28 parked fibres, 13 skies n 4

Batch-Mode Reduction 6 d. FDR, RUNZ on separate V, R and spliced VR data using 6 d. FDR arc-line lists (see later!) n IRAF dofibers on V, R data using my own arc-line lists (NIST Atomic Spectra Database: n http: //physics. nist. gov/cgi-bin/At. Data/lines_form) IRAF xcsao on R grating data only n No heliocentric correction applied (raw redshifts only) n 5

Comparison Spectra - 1 IRAF data not flux-calibrated 6

Comparison Spectra - 2 IRAF data not flux-calibrated 7

Signal-to-noise comparison (mean for 109 galaxies) RUNZ R 10. 3500 RUNZ V 9. 4253 RUNZ VR 8. 8476 IRAF R 3. 4753 Data from: IRAF - measured in splot; RUNZ - 0924 Rcom. sdfz. zlog 8

Problems encountered n n n Discovered Hg. Cd. Ne line list has too few Ne, extra Ar and miscellaneous lines High-dispersion data: only 13 good arc lines in Hg. Cd. He line list: - 6 d. FDR throws away 3 worst lines - can’t afford this! Heliocentric correction incorrectly applied, correct on: /net/aaowfi/data 1/will/runz 6 df_may 03 9

Arc spectrum R - Hg. Cd. Ne 10

R-arc line-identification compared (subset of 10 fibres) # lines in line list IRAF 6 d. FDR 61 46 mean rms 0. 1930 of disp function 0. 1584 mean # lines fitted 29. 5 39. 5 Data from: IRAF – arcapid. t. ms; 6 d. FDR – arclist 006. dat On 108 spectra, mean rms IRAF 0. 1816; 6 d. FDR 0. 1539 11

Line lists and matched lines in dispersion functions n Red: neon lines to be added n Blue: 6 dfdr desert IRAF 6 d. FDR n 12

Arc spectrum R - Hg. Cd. Ne 13

Arc spectrum V - Hg. Cd. He Not enough lines in highdispersion data to be used for Dn-s measurements ? Even with extra lines from NIST ASD, still only 16 good lines n n 14

Agreement: batch x-cor results V data, R data and VR data compared n Dz ≤ 0. 0005 (150 km/s) out of 109 spectra n RUNZ R IRAF R 45 RUNZ V 43 57 69 78 RUNZ VR 15

RUNZ-VR misidentifications 11/109 V 21/109; R 28/109 z = ~ 0. 09 16

R data: 109 galaxies - r-h plots from both x-correlations - “disagrees” are low S/N spectra Data from: IRAF – xcsao. log; RUNZ – read from display (r writes to log) 17

Mean uncertainty in x-correlation 109 galaxies RUNZ R RUNZ VR IRAF R ± 79 km/s (z ± 0. 0003) ± 84 km/s (z ± 0. 0003) ± 59 km/s (z ± 0. 0002) ± 41 km/s (z ± 0. 0001) Data from: IRAF – xcsao. log; RUNZ – verr from 0924 Rcom. sdfz. zlog IRAF uses 12 templates, RUNZ uses 8 templates 18

X-correlation R data well-matched galaxies 57 Error bars are x-correlation uncertainties 19

X-correlation R data All 109 galaxies 20

Line Measurements – 9 galaxies 21

Summary Results n n n n n S/N appears higher in RUNZ than in IRAF Line lists should be reviewed 6 d. FDR should have “retain all lines” option Update all versions of RUNZ to do heliocentric correction properly Can’t batch-process – still need to check for misidentifications Disagreements between methods and gratings on low S/N data not a matter of concern X-cor uncertainty could be quoted on RUNZ screen display and should be mentioned in online database May reduce uncertainty by including more templates for RUNZ Overall z values concur in cases of proper identification … and keep in mind … 22

Results from these analyses are preliminary! Many more fields will be studied n VPH grating data will be compared with reflection grating data n Repeatability of measurements will be tested on repeat observation if possible n 23

Thanks n n n Anglo-Australian Observatory Wide-Field Astronomy Unit, Edinburgh Macquarie University 6 df Galaxy Survey Team (37 members) Will Saunders, AAO Quentin Parker, MU/AAO 24