A New Atlas of theDiffuse Interstellar Bands: HD 183143

Lewis M. Hobbs

Yerkes, U. ChicagoDonald G. York

U. ChicagoJulie A. Thorburn Dahlstrom

Carthage CollegeTheodore P. Snow

U. ColoradoMichael Bishof

U. ChicagoScott D. Friedman

STScIBenjamin J. McCall

U. IllinoisTakeshi Oka

U. ChicagoBrian Rachford

Embry-RiddlePaule Sonnentrucker

STScIDaniel E. Welty

U. Illinois

The APO DIB Survey• Apache Point Observatory 3.5-meter• 3,600–10,200 Å ; / ~ 37,500 (8 km/s)• 119 nights, from Jan 1999 to Jan 2003• S/N (@ 5780Å) > 500 for 160 stars (114 reddened)• Measurements & analysis still very much underway

Our Previous Atlas: HD 204827

• EB-V=1.11, V=7.94

• Strongest “C2 DIBs”

• Highest column density of C3

• Double-lined spectroscopic binary!– Spectral Types O9.5 V & B0.5 III

• 380 DIBs unambiguously detected

• ApJ 680, 1256 (2008)

Credit: robgendlerastropics.comHD 204827

Our Newest Atlas: HD 183143

• EB-V= 1.27, V=6.92, B7Iae

– [Unfortunately, not a binary!]

• Well studied by Herbig, others

• No detectable C2 or C3

– Distinct chemical environment

• 414 DIBs detected (135 are “new”)

• DIB population systematically redder, broader, and stronger than HD 204827

• Total DIB count now ~545

Our Website: http://dibdata.org

http://dibdata.org