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Absolute Proper motions Out side the Plane(APOP). A step towards the GSC2.4. Zhaoxiang Qi, Yong Yu, Richard L. Smart, Mario G. Lattanzi, Zhenghong Tang, Beatrice Bucciarelli, Alberto Vecchiato, Alessandro Spagna, Brian J. McLean. 29 August, 2012. Outline. Backgrounds
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Absolute Proper motions Out side the Plane(APOP) • A step towards the GSC2.4 Zhaoxiang Qi, Yong Yu, Richard L. Smart, Mario G. Lattanzi, Zhenghong Tang, Beatrice Bucciarelli, Alberto Vecchiato, Alessandro Spagna, Brian J. McLean 29 August, 2012
Outline • Backgrounds • Overview on the principle and the reduction procedure • Verifications of the results • Conclusion and future works
Backgrounds • APMs of adequate objects without P.d.E., M.d.E. and C.d.E are very important(indispensable) for Milky Way studies(e.g. rotation curves, structure...). • Most of the faint (R~20mag) catalogues are not really in the ICRS and did not deal with P.d.E., M.d.E. and C.d.E, especially their proper motions system. (e.g. USNOB1.0, PPMXL?, GSC2.3 did not publish PMs...) • Some of the faint APMs catalogues are now in the ICRS(e.g. SDSS-USNOB1, SDSS-GSC2.3...), but the sky cover is not well-distributed (limited in SDSS regions) and M.d.E. and C.d.E are still there.
Backgrounds • APOP is a faint (R~20.8) positionally well-characterized(|b|>27deg.) and pure APMs catalogue in the ICRS. (pure=reducing the P.d.E., M.d.E., C.d.E. and using only GSC plates data) • Reduction of APOP was finished at the end of 2011.
Backgrounds Sky distribution of Schmidt plates used in APOP 4239 plates-->22,525 sq.deg. Equatorial coordinate system Galactic coordinate system
Backgrounds • Average accuracy of the measured coordinates on GSC plates: star 0.2-0.3 arcsec, nonstar 0.2-0.5 arcsec, A few plates data errors increased by 1.7. • Average accuracy of the photometry: 0.13-0.22 mag. • Number of observations for one object: 6-15. • Number of galaxies on one plate: 8000-20,000. • Epoch span: 25-45 years.
Principle • Objects (stars and galaxies) with close positions, magnitudes and colors on the plate have similar systematic errors. • APMs of extragalactic-objects are always zero and not dependent on their positions, magnitudes and colors on plate.
Principle • Do the M.d.E. and/or C.d.E. exist in plates data? • Are the M.d.E. and/or C.d.E. of stars the same as galaxies?
Principle Distributions of stars and nonstars as a function of mag. and color Stars Stars Non-stars Non-stars Plate Epoch Zenith RA Dec l b XE003 1954.9 51.2 44.9 84.5 126.1 22.4 XP003 1996.8 52.1 38.6 85.2 125.3 22.6
Principle M.d.E. of all the objects Bin=0.3mag 10,000 objects/bin Amplitude X~110mas Y~220mas Nonlinear Blue - Infrared XJ003 - XI003(epoch span=1996.717-1996.719)
Principle C.d.E. of all the objects all objects Bin=0.2mag Amplitude X~110mas Y~220mas Nonlinear Blue - Infrared
Principle • Do the M.d.E. and/or C.d.E. exist in plates data? YES and very common. • Are the M.d.E. and/or C.d.E. of stars the same as nonstar?
Principle C.d.E. of stars and nonstars
Principle • Do the M.d.E. and/or C.d.E. exist in plates data? Yes and very common. • Are the M.d.E. and/or C.d.E. of stars the with nonstar? Yes, very similar.
P.d.E. of stars after using Moving Sub-Plate method P.d.E. of stars as a function of plate position after the cubic polynomials fitting. pseudo-proper motions of real galaxies as a function of position. ( after picking out from nonstars) XP715 epoch=1996.3 XE494 epoch=1955.3 (l=266.9, b=69.2)
M.d.E. of galaxies本 C.d.E. of galaxies本
Verifications • Internal verification: formal errors of the calibrated unknowns Bin=0.3mag 1000,000 objects/bin
Verifications • Internal verification: APMs differences of common stars in overlap regions Typical overlap region: 1.5*6.5 sqr.deg. Grid=0.25*0.25 sqr.deg. 300 objects/grid
Verifications • External verification: Dispersion of “APMs” of the QSOs(should be around zero) is an independent and direct determination of the qualities of stellar APMs. 108,521 QSOs found in the APOP (via cross-matching with the LQRF catalogue)
APMs of QSOs as a function of magnitude APOP No significant M.d.E.
APMs of QSOs as a function of color APOP No significant C.d.E.
APMs of QSOs as a function of RA, Dec. APOP No significant P.d.E.
Verifications • External verification: APMs comparisons between the APOP, PPMXL and PMGS. PPMXL: USNOB1.0+2MASS+PPMX+UCAC3 PMGS: GSC2+SDSS APOP: GSCII-database
APMs of QSOs in PPMXL and APOP
APMs of QSOs as a function of RA, Dec. PPMXL Wu Z. Y. et.2012
Conclusion and future works • The first version of APOP was achieved and the paper is being finalized for submission. • A new method of source classification for galaxies is presented. • A new method of removing P.d.E in position is used. • A recalibration version of APOP is planned.(Using the new Photometry and fixing the cluster problem).
REFERENCES • SDSS-USNOB1,Munn et al. 2004, 2008; Gould & Kollmeier 2004 • SDSS-GSC2.3 Ricky et al. 2011 • Lasker et al., 2008, \aj, 136:735-766 • A. Spagna et~al., 1996, \aap, 311, 758-777 • Andrei et al., 2009, \aap, 505, 385-404 • Wu Z. Y. et al., 2011,\aap
Visiting LAMOST Bea, Cátia, Hugh, Mario, Ricky, Zenghua, Liao, Zhenyu, Zhaoxiang. • Departuring from CNCC Thursday(8/30): • Gathering Time: 1:30 pm Place: Entrance gate C1 of CNCC. • Arriving at LAMOST(around 4:00pm): • 1. Put your baggage to your apartment. • 2. Visit the main components of LAMOST at 5:00pm. • 3. Have dinner in its canteen at 6:00pm. • 4. Look the real observations in its Observing Control Room around 8:00pm. • 5. sleep. • Back to CNCC Friday(8/31): • 1. 7:30 am, Breakfast, place: canteen. • 2. 8:10 am, leave the Xinglong station, place: canteen. • 3. Arrive CNCC around 11:00am.