The sdss dr7 white dwarf catalog
This presentation is the property of its rightful owner.
Sponsored Links
1 / 20

The SDSS DR7 White Dwarf Catalog PowerPoint PPT Presentation


  • 63 Views
  • Uploaded on
  • Presentation posted in: General

The SDSS DR7 White Dwarf Catalog. S.J. Kleinman, S.O. Kepler, D. Koester, V. Pe ç anha, I. Domingos Pelisoli, J.E. da Silveira Costa, P. Dufour, J. Krzesinski, H. Harris, A. Nitta,. The First Sloan Digital Sky Survey White Dwarf Catalog

Download Presentation

The SDSS DR7 White Dwarf Catalog

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The sdss dr7 white dwarf catalog

The SDSS DR7 White Dwarf Catalog

S.J. Kleinman,

S.O. Kepler, D. Koester,

V. Peçanha, I. Domingos Pelisoli, J.E. da Silveira Costa,

P. Dufour, J. Krzesinski, H. Harris, A. Nitta,


Doubling the number of white dwarf stars

The First Sloan Digital Sky Survey White Dwarf Catalog

Kleinman, Harris, Eisenstein, Liebert, Nitta, Krzesinski,...

ApJ 2004May20 V.607, P.426

Doubling the Number of White Dwarf Stars:

EUROWD 2004


What s in it

1888 DAs

200 WDM pairs

171 DBs

134 DCs

57 DZs

45 DQs

30 DHs

13 DOs

157 uncertain WDs

What's In It?

  • Data from SDSS DR1: www.sdss.org/dr1

  • Hand-ID'd ~9000 spectra (complete)

  • Photometry (ugriz), Spectra (~3800--9200Å), PMs, Finder Charts, Fits,...

  • 2,551 WDs & 240 Hot SDs

EUROWD 2004


The sdss dr4 white dwarf catalog

Scot J. Kleinman (Subaru)

Daniel Eisenstein (U. AZ/Steward Obs.)

Jim Liebert (U. AZ/Steward Obs.)

Hugh Harris (USNO Flagstaff) &

the rest of the SDSS WD collaboration

Paper accepted to ApJSupp.

astro-ph/0606700

(also www.sdss.org/dr5)

The SDSS DR4 White Dwarf Catalog

EUROWD 2006


Summary

Summary

  • 9316 spectroscopically-confirmed WDs

  • Approx. 6000 new discoveries – roughly doubling McCook and Sion post SDSS-DR1 catalog.

  • 8000 DAs; 713 DBs; 289 DCs; 133 DZs, 104 DQs; 31/10 DO/PG1159s; 27 WDs; 9 DHs; (774 duplicate spectra).

  • 928 subdwarfs.

  • Usual spectra, photometry, fits to DA/DB Teff and log_g, proper motions, SDSS ID numbers.

  • Online at www.sdss.org/dr5 -> data products -> value-added catalogs -> DR4 WD catalog (das.sdss.org/wdcat/dr4).

EUROWD 2006


Fits literature comparisons

Fits: Literature Comparisons

This is similar to what was seen in the DR1 catalog, but we think we have an explanation now!

EUROWD 2006


The next dr6 sdss wd catalog sdss wd catalog ds9

Scot Kleinman

Gemini Observatory

[email protected]

Detlev Koester

models, comparison fits

Daniel Eisenstein

autofit code

SDSS WD Group

European White Dwarf Workshop 2008

The Next (DR6) SDSS WD Catalog(SDSS WD Catalog-DS9)

EUROWD 2008


What s new in the catalog

What's new in the Catalog?

  • New models, improved physics, better grid

  • Will re-fit ALL SDSS Catalog WDs with new models and latest reductions – putting all now on the same footing

  • 3,683 (and counting...) new WDs since DR4. Just straight DAs and DBs so far.

  • Questions:

    • Restrict to g<19, SN>20?

    • Quick or complete? “Normal” or Exotic”?

    • DR6/DR7/DR8...?

    • Online access?

EUROWD 2008

EUROWD 2008


New dr6 wds

New DR6 WDs...

EUROWD 2008


Why am i here again

Why am I here again?

  • Catalog now based on DR7

  • Brazilian ambition gained the upper hand and human IDs now complete

    • ~43,000 candidates

    • ~25,000 human IDs

  • ~19000 (+ 1000 uncertain) WD spectra containing ~1700 duplicates

  • Journal submission planned this year (we're almost there)


The vital statistics

437 DZs7.7, 3.3 x DR1, DR4

218 DQs4.8, 2.1 x DR1, DR4

48 DOs3.7, 1.2 x DR1, DR4

1640 WDMs8.2 x DR1

98 Mixed WDs

1135 Uncertain WDs

1409 Subdwarfs

The Vital Statistics

  • 13724 DAs7.3,1.7 x DR1,DR4

  • 961 DBs5.6,1.35 x DR1,DR4

    • 57 DBM, 108 DBZ, 89 DB*, 346DB*:9.1, 2.2 x DR1,DR4 DBs

  • 1028 DHs 34.3,114 x DR1,DR4

    • 785 DAH

    • 62 DBH

  • 609 DCs4.5, 2.1 x DR1,DR4


Id self consistency

ID self-consistency

  • 1683 objects with 3591 duplicate spectra

    • 242 WD IDs disagree

      • 212 agree in dominant subtype

        • 13 differ by only a colon

        • 141 differ by a subtype or a subtype and a colon

        • 58 differ by more than one subtype

      • 30 disagree in dominant subtype

        • DBA <> DAB, DQ <>DC, DA<>SDB, ...

        • still analyzing these


Id self consistency1

ID self-consistency

  • 10090 WDs in DR4 catalog Table 11

    • 8527 of our IDs agree

    • 1563 disagree

      • 1330 agree in dominant subtype

        • 254 differ by only a colon

        • 591 differ by a subtype or a subtype and a colon

        • 485 differ by more than one subtype

      • 227 disagree in dominant subtype

  • Initially, 509 escaped our ID process and ...

  • ... 242 did not make our candidate list

  • (These have been added, now.)


Id self consistency2

ID self-consistency

  • Comparison toliterature values

  • For pure DA/DBs

  • 205 Objects

  • Previously, we had increasingly higher T than others at large T.


Model grid

Model Grid

  • Models and grid roughly as described in 2008

    • Latest Koester models

      • Includes neutral broadening improvements, Tremblay & Bergeron (2009) VCS tables

      • Hooper microfield distribution with modifcations from Nafonov et al. (1999)

      • DBs use ML2/1.25

    • Grid density increased and made more uniform

    • Extended to log(g)=10.0 and Teff(DB) to 50,000K


Candidate generation

Candidate Generation

  • Two-pronged candidate strategy

    • 1: Reproduce DR4 color / PM / z / flag ... selection entirely within DR7 CAS : 24189 spectra

    • 2: Use targeting and SEGUE classification output to add anything targeted or analyzed to be a possible white dwarf star : 48198 spectra

  • 49046 unique spectra (18981 spectra satisfied both sets of criteria)

    • 78% of spectra satisfying both criteria were WDs

    • 30% / 6% for satisfying only DR4 / SEGUE

  • Used other SDSS catalogs to reduce sample further to 33430 spectra


Magnetic eyes

Magnetic Eyes?


Liberal eyes

Liberal Eyes!


Summary1

Summary

  • DR7 Catalog roughly 2xDR4 – coming this year!

  • Ambitious Brazilians lead to conservative “pure” DA/DB eyeballed sample

  • When in doubt, look at the images!

  • When in doubt, it's probably a selection effect!

  • DR8 to contain final SEGUE-II spectra – due December, 2010


  • Login