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Processing Status June 2009 Mary Williams Padova Meeting, 11/06/09
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Talk Outline Mary Williams Padova Meeting, 11/06/09 Archive status Data flow New Status Reports Zero-points FP3 Stellar parameters: temperatures
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Archive status Mary Williams Padova Meeting, 11/06/09 As of 9th June 2009 285,503 spectra Last date in internal and reduced archives: 20090328 Last date in raw archive: 20090328
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 First year data 25,689 RVs, ~4,500 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Second year data 26,906 RVs, ~5,000 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Third year data 37,292 RVs, ~8,800 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Fourth year data 87,261 RVs, ~17,200 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Fifth year data 41,002 RVs, ~11,000 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Sixth year data 59,945 RVs, ~11,000 deg 2
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Sky Coverage Mary Williams Padova Meeting, 11/06/09 Full database 218,100 RVs, ~32,000 deg 2
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Current data flow Mary Williams Padova Meeting, 11/06/09 SSO AAO (Warren) Padova Reduction (Alessandro) AIP Archive AIP Pipeline (Mary) AIP Processed Data Archive Problem fields Fortnightly 3-4 days Internal release (at AIP) Reduction problem fields Fortnightly Weekly Eyeballing of spectra (Rachel, Tomaz, Gal, Paola) Complete to Dec 2007 1/2 week Irregular AIP archive Last release complete to March 2009
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New status reports Mary Williams Padova Meeting, 11/06/09
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New status reports Mary Williams Padova Meeting, 11/06/09
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New status reports Mary Williams Padova Meeting, 11/06/09
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New status reports Mary Williams Padova Meeting, 11/06/09
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New status reports Mary Williams Padova Meeting, 11/06/09
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Zero-points Mary Williams Padova Meeting, 11/06/09 What are they? Temperature fluctuations cause shift in wavelength between science frames and arc frames Mostly of the order of a 1-5 km/s We correct with zero-point RVcorrection ZeroPointQualityFLAG denotes quality of zero- point correction - mostly!!
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Zero-points Mary Williams Padova Meeting, 11/06/09 How do we calculate the correction? Un-sky subtracted spectra from single fibre Sky template SkyRV, eSkyRV, R for single fibre THEN….
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Zero-points Mary Williams Padova Meeting, 11/06/09 THEN we do a polynomial fit across the field SkyRV and eSkyRV Exclusive sky fibre (weight=5xR) Weight by R value Threshold of R=5 The fit gives RVcorrection
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ZeroPointQualityFLAG gives the quality of the fit 1st character: FIELD fit quality Dispersion between SkyRV - RVcorrection 2nd character: Sub-group fit quality Dispersion between SkyRV - Rvcorrection for regions 1-50, 51-100, 101-150 *: If interval between usable sky velocities > 15 Zero-points Mary Williams Padova Meeting, 11/06/09
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Zero-points Mary Williams Padova Meeting, 11/06/09 The fit can sometimes be very bad… Fiorangela La Forgia It can become unbound if there are insufficient fibres with R>5
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Zero-points Mary Williams Padova Meeting, 11/06/09 Sometimes bad zero-points are hard to spot X-correlation with sky has |50| km/s limit If outside those bounds SkyRV=0, eSkyRV=0 or large, R<0.1 The RVs for such spectra can be wrong by as much as 100 km/s! Affects small number of fields These data are removed from the database
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Zero-points Mary Williams Padova Meeting, 11/06/09 The other bad fits are hand corrected All zero-points fits are eyeballed Those with unbound fits are manually corrected New flagging of affected spectra: ZeroPointQualityFLAG=‘M’ However, there has been an increase in problem fields… Fiorangela La Forgia
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Zero-points Mary Williams Padova Meeting, 11/06/09 There were a number of causes of this increase Shift to brighter stars, lower exposure time Exposure times increased back again Poor placement of sky fibres More care taken Deterioration of fibres meaning lower S/N FP3 There is a backlog of correcting these fits manually Be wary if |RVcorrection| > 10 km/s or *! If find some high RV stars, check fellow fibres
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Zero-points Mary Williams Padova Meeting, 11/06/09 Correlation between RV and SkyRV Caused by underlying stellar spectrum “tugging” on sky correlation Not a problem for zero point calibration IF there is no mean offset in stellar RVs for one field…BUT…
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Zero-points Mary Williams Padova Meeting, 11/06/09 There might be such a issue Whole fields have have a non-zero mean RV Causes shift in Rvcorrection of the order of a couple of kms -1 Work in progress
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Field Plate 3 Mary Williams Padova Meeting, 11/06/09 The first 8 FP3 fields New stiffer cabling used - potential problems! Check stability of SkyRV Grey : R < 5 Black: R > 5
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Field Plate 3 Mary Williams Padova Meeting, 11/06/09 Stability of SkyRV for R > 5 FP3: (SkyRV)=-0.5 kms -1, (SkyRV)=1.9 kms -1 FP1: (SkyRV)=-0.4 kms -1, (SkyRV)=2.9 kms -1 FP2: (SkyRV)=-0.4 kms -1, (SkyRV)=2.2 kms -1
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Field Plate 3 Mary Williams Padova Meeting, 11/06/09 Some of the fields include repeat observations All but one field look good
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Field Plate 3 Mary Williams Padova Meeting, 11/06/09 The problem field was one of the earlier ones So ignoring this field and |RV(FP3) - RV(previous)| < 20 kms -1
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Field Plate 3 Mary Williams Padova Meeting, 11/06/09 Stability of SkyRV for R > 5 FP3: (RP3 RV-previous RV)=-0.5 kms -1 68.2%: =1.1 kms -1 95%: =2.3 kms -1 ALL: (RP3 RV-previous RV)=+0.2 kms -1 68.2%: =1.4 kms -1 95%: =3.8 kms -1
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Stellar Parameters Mary Williams Padova Meeting, 11/06/09 Comparing RAVE temperatures to others To spot any possible systematic in RAVE temperatures Use a variety of reference temperatures: PPhotometric: V-K using Ramirez calibrations with reddening corrections and constraints PJon’s spectroscopic temperatures: excitation balance PSoubiran and Girard temperatures: photometric, excitation balance, H PCayrel compilation temperatures: photometric, H Thus we have a broad range of methods to compare our temperature calculations to
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Stellar Parameters Mary Williams Padova Meeting, 11/06/09 There is a significant systematic for the dwarfs GREEN - V-K photometric BLACK - Jon’s calculation CYAN - Soubiran and Girard PURPLE - Cayrel
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Stellar Parameters Mary Williams Padova Meeting, 11/06/09 It remains at higher S/N values GREEN - V-K photometric BLACK - Jon’s calculation CYAN - Soubiran and Girard PURPLE - Cayrel
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Summary Mary Williams Padova Meeting, 11/06/09 Processing continuing as normal New status reports to aid dissemination of data and identification of problems Zero-points Removal of bad fields Manual refitting backlog: watch out! Possible problem with star RV correlation - investigating FP3 Sky RVs good Repeats good, apart from mean offset - investigating New report out soon Possible temperature systematic
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