1. The MUSYC Census of Protogalaxies at z=3
Re-add NSF AAPF for AAS meeting
Eric Gawiser
Yale University
MUSYC E-HDFS UBR composite

2. Protogalaxies at z=3: TLAs
LBG=Lyman Break Galaxy
selected via Lyman break, blue continuum (starburst)
LAE=Lyman Alpha Emitter
selected via strong emission line (early stage of star formation)
DRG=Distant Red Galaxy
selected via Balmer break in observed NIR
AGN=Active Galactic Nucleus
selected in X-rays, Mid-infrared and/or via LBG-like colors
DLA=Damped Lyman  Absorption system
selected in absorption, N(HI)>1020 cm-2
“TLA is a three letter acronym for… Three Letter Acronym” (not Tender Loving Affection)
All make use of hydrogen!

3. Demographics of Protogalaxies
Goals:
Cosmological quantities (e.g. cosmic star formation rate density) should be summed over all objects, not just Lyman Break Galaxies, which trace the bright end of the (rest-frame ultraviolet) luminosity function
Determine if the progenitors of typical galaxies like the Milky Way are found amongst the zoo at z=3.
Approaches:
Go deeper with one selection technique until you detect all of the galaxies.
Example: dim Lyman Break Galaxies in HUDF.
Drawback: spectroscopic confirmation impossible so little can be learned about population found.
Apply all selection techniques in same volume of the universe to measure overlaps in populations and get a full census.
Drawback: need a carefully designed multiwavelength survey.
Turn that into an advantage - MUSYC

4. MUSYC (Multiwavelength Survey by Yale-Chile)
Eric Gawiser (Yale, P.I.)
Pieter van Dokkum (Yale, P.I.)
Paulina Lira (U. Chile)
José Maza (U. Chile)
Meg Urry (Yale)
Martin Altmann (U. Chile)
F.J. Castander (IEEC-Barcelona)
Daniel Christlein (U. Chile/Yale)
Paolo Coppi (Yale)
Harold Francke (U. Chile Ph.D. student)
Marijn Franx (Leiden)
David Herrera (Yale)
Leopoldo Infante (P.U. Catolica)
Sheila Kannappan (U. Texas)
Charles Liu (CUNY/AMNH)
Danilo Marchesini (Yale)
Rene Méndez (U. Chile)
Ryan Quadri (Yale Ph.D. student)
Ned Taylor (Leiden Ph.D. student)
Ezequiel Treister (U. Chile Ph.D. student)
Shanil Virani (Yale Ph.D. student)
Sukyoung Yi (Yonsei)
Gawiser et al 2005, ApJS, astro-ph/

5. MUSYC: A Square-degree Survey of the Formation and Evolution of Galaxies and their Central Black Holes Science Projects:
Census of protogalaxies at z=3
AGN demographics at 0<z<6
Proper motion + color survey for white and brown dwarfs
Groups and clusters at z<1
Recent star formation in ellipticals
Low surface-brightness galaxies
Quasar lensing statistics
Public outreach (Hayden Planetarium)

6. Extragalactic Atlas of the Hayden Planetarium’s Digital Universe Download from and run on your laptop for classes and personal sense of awe
Survey
Mag. Limit
# of galaxies with redshifts
# of quasars with redshifts
SDSS
r'<21
229293
374724
2dF
R<19 gals,
R<21 qsos
50748
22431
MUSYC (UBVRIzJHK photo-z’s)
R<26
obj.
(90% galaxies)
~500

7. Origin of the Lyman break
Steidel & Hamilton 1992

8. Lyman Break Galaxy (LBG)

9. LBG in E-CDFS, R=22.8, z=3.38 strong Ly emission (EW=60Å, SFRUV ≥350 M/yr) numerous chemical absorption features (6 hr IMACS exposure)
OI/SiII
SiII
CDFS-12485
SiII 1260, OI/SiII 1303, CII 1334, SiIV 1394,1402, SiII 1527, CIV 1549, FeII 1608
SiII
CIV
FeII
CII
SiIV
MUSYC
Gawiser et al 2005
Ly 

10. Lyman  Emitter (LAE) U B NB5000 V R
Gawiser et al 2006, ApJL submitted
(MUSYC plus Caryl Gronwall,
Robin Ciardullo, John Feldmeier)

11. LAE in E-CDFS, R=25.7, z=3.085 Ly EW=200Å, SFR≥30 M/yr (6 hr IMACS exposure)
SFR agrees for both UV and Ly

12. Lyman Alpha Emitters probe the z=3 luminosity function much deeper than Lyman break galaxies (R<25.5)

13. UVR colors of confirmed LAE are consistent with those of LBGs
No interlopers found, but sample of HII galaxies at lower EW
Confirmed LBG
Confirmed LAE
Disagrees with claims of red LAEs
by Stiavelli et al 2001, Campos et al 1999

14. Conclusions
MUSYC data release (images and catalogs): and
Gawiser et al. 2005, ApJS, astro-ph/
LAEs probe the z=3 luminosity function deeper than LBG samples but have similar colors, revealing rapid SF.
All protogalaxy families (including LAEs undergoing possible first burst of star formation) have dark matter halo masses of 1011M. Typical (unbiased) z=3 dark matter halos have 109M. Was galaxy formation supressed in those halos?