Transcript Probing Galaxy Evolution with GALEX

Center for Astrophysical Sciences
at Johns Hopkins University 1
Baltimore, Maryland, USA
Node Coordinator: Tim Heckman
Alex Szalay, professor
Tamas Budavari, postdoc
Charles Hoopes, postdoc
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA
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ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA
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ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA
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ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
Cooperative agreement for
Research in astrophysics
Between JHU and GSFC
Laboratory for High Energy
Astrophysics (LHEA)
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA
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ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
Apache Point Observatory
Cloudcroft, New Mexico
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SDSS telescopes
ARC 3.5 meter
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SPIcam – optical imager
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Echelle spectrograph
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1μm to 2.5μm
NIC-FPS – NIR camera and Fabry-Perot Spectrometer
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Simultaneous red and blue spectra
3600 to 8000Å – 0.8 to 3 Å/pixel
GrIm II infrared imager and spectrograph
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3500 to 9800Å
R=37,500
Double Imaging Spectrograph
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5’ FOV
0.14 “/pix
0.85 to 2.5 μm
JHU has a share of the time, and we have experience
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA





ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
Far Ultraviolet Spectroscopic Explorer (FUSE)
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Spectroscopy from 905 – 1180Å, velocity resolution ~20 km s-1
Tim Heckman and Charles Hoopes are affiliated with the FUSE
Science Team
FUSE Science
• Metallicity of neutral gas in I Zw 18
(Aloisi et al. 2003)
• 105 K gas in starburst superwinds
(Heckman et al. 2001, Hoopes et al. 2003)
• H2 absorption in starbursts
(Hoopes et al. 2004)
• FUV SEDs and Extinction in starbursts
(Buat et al. 2002)
• FUV stellar libraries for OB stars
(Pellerin et al. 2002, Robert et al. 2003)
Currently in safe mode, but expected
to return to service
I Zw 18: Aloisi et al. 2003
Center for Astrophysical Sciences
at Johns Hopkins University
Baltimore, Maryland, USA





ACS: Advanced Camera
for Surveys
JHU/GSFC Co-op
Apache Point Observatory
FUSE: Far Ultraviolet
Spectroscopic Explorer
GALEX: Galaxy Evolution
Explorer
GALEX: The Galaxy Evolution Explorer
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Launched April 28, 2003
Imaging in two UV bands
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Slitless Spectroscopy
1350-2800Å
 R=80-300
Tamas Budavari,
Alex
Szalay,
Tim
Heckman,
Charles
Hoopes
on the
GALEX Science Team
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FUV: λ=1516Å, Δλ=268Å
NUV: λ=2267Å, Δλ=732Å
Spatial resolution ~5”
FOV ~1.2 deg2
GALEX Surveys
Name
Area*
(Sq. deg.)
Exposure
(seconds)
Mlim
#
galaxies
<z>
All-sky Imaging Survey (AIS)
35,000
100
20.5
107
0.2
Medium Imaging Survey (MIS)
1,000
1,500
23
106.5
0.6
Deep Imaging Survey (DIS)
80
30,000
25
107
0.8
Ultradeep Imaging Survey (UIS)
4
200,000
26
105.5
0.9
Nearby Galaxy Survey (NGS)
200
1,500
27 arcsec-2
200
0.001
Wide-field Spec. Survey (WSS)
80
30,000
20
104.5
0.15
Medium Spec. Survey (MSS)
8
300,000
21-23
104.5
0.5
Deep Spec. Survey (DSS)
2
1,500,000
22.5-24
104.5
0.9
* Planned area
Probing Galaxy Evolution
with GALEX
Combo-17
 NOAO Deep WideField Survey (NDWFS)
 Ultraviolet Luminous
Galaxies
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COMBO-17 / CDFS
17 band optical photometry (Wolf et al. 2004)
 Photometric redshifts with δz/(1+z)<0.1 at
R=24
 Redshifts out z=1
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Combo-17 filters
GALEX CDFS Data
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GALEX FUV (1500Å) and NUV (2300Å)
 Part
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of the Deep Imaging Survey (DIS)
CFDS_00: 44 ksec, 1sq deg
 AB=25
in FUV,NUV
CDFS_01: 31 ksec, 1 sq deg
 GALEX data are public as of January 2005
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Evolution in the Mass-Dependent Star
Formation History of Galaxies from z=0 to 1
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Use GALEX + (aperture corrected) Combo-17
photometry and library of BC03 models (following
Kauffmann et al., Salim et al., etc) to derive:
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From GEMS catalog:
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SFR, UV Extinction, Stellar Mass
Sersic indices, Half-light radii, Surface mass density, SFR/area
Extend work of Kauffmann et al. and Brinchmann et al.
to z=1
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Examine SFR distribution vs. many parameters as a function of
redshift (Mass, surface density, SFR, extinction, size, Sersic
index)
Examine how SFR/M, SFR/size, Extinction varies with mass,
surface density
NOAO Deep Wide-Field Survey (NDWFS)
co-PIs: Arjun Dey & Buell Jannuzi
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Deep optical and NIR survey of two
9.3 sq. deg. fields
 Boötes Field (NGPDWS) –
North Galactic Pole
 Cetus Field – Roughly 30
degrees from SGP
 KPNO and CTIO 4-meters,
MOSAIC
Survey detection limits (5σ):
 BW, R, I – AB=26
 J,H,K – AB = ~21
Survey Status
 All data obtained
 Boötes field public release in
October 2004: BWRIK images,
single-band and matched
catalogs
GALEX Observations of Bootes
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GALEX Coverage of Boötes field
 DIS (AB = 25 in NUV, FUV) 9 sq. deg. (not yet complete)
 UDIS (AB = 26 in NUV, FUV) 1 sq. deg.
(soon will have 90,000 seconds!)
 DSS (AB = 22.5-24) 1 sq. deg.
Additional U-band data in Boötes field (GALEX/NDWFS
collaboration)
 Entire field imaged to AB=25
 1 sq. deg. imaged to AB=26
Observations planned or taken with Chandra, Spitzer, VLA FIRST,
Redshifts from MMT Hectospec (AGES), Gemini GMOS
Steidel et al. 2003
GALEX-NDWFS 2 color diagram
GALEX-NDWFS 2 color diagram
GALEX-NDWFS Science
Star Formation and Extinction Properties of Galaxies at z=1 and 2
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Once high-z populations are isolated, derive LF, extinction
corrections, corrected LF, SFR density to compare with z≥3
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Need better redshifts than dropout technique
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Spitzer IRAC data to improve SEDs for photo-z, and MIPS data to
compare UV/FIR
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Use Lyman break in DSS to isolate z~0.6 sample
Investigation of Galaxies at Intermediate Redshifts in the AGES
sample
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Redshifts and multiwavelength data for galaxies with I<20
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NIR + Optical + UV spectral evolution modeling, following to Salim
et al. (2004)
Ultraviolet Luminous Galaxies (UVLGs)
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First sample described in Heckman et al. (2005)
Matched GALEX All-Sky Imaging Survey IR0.2 with SDSS DR1
galaxies (Seibert et al. 2005)
 74 “UV luminous” galaxies (LFUV>2×1010 L๏) between 0.1<z<0.3
[L* = 4×109 L๏ at z=0 (Wyder et al. 2005), L* = 6×1010 L๏ at z=3
(Arnouts et al. 2005)]
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Co-moving density 10-5 Mpc-3 (>100× less than LBGs at z=3)
Additional properties (metallicities, age indicators, SFRs, stellar
mass, etc.)
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SDSS value-added catalogs (www.mpa-garching.mpg.de/SDSS)*
Spectral evolution modeling by Salim et al. (2005)
Recently increased sample to 204 using DR2 and IR0.9
*see Kauffmann et al. 2004, Brinchmann et al. 2004, Tremonti et al. 2004
Structural Properties
FUV Luminosity vs. Half-light Radius
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“Large” UVLGs (IFUV<108 L๏ kpc-2)
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No correlation between LFUV and
size
Strong correlation between IFUV and
stellar mass
(kpc)
UVLGs span a large range in size
(L๏/kpc2)
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Massive (log M*=10.5 – 11.3)
High-mass disk systems with young
stellar population
“Compact” UVLGs (IFUV>108 L๏ kpc2)
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Low mass (log M*=9.5 – 10.7)
Mass range similar to LBGs
(L๏)
Structural Properties
FUV Surface Brightness vs. Stellar Mass
UVLGs span a large range in size
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“Large” UVLGs (IFUV<108 L๏ kpc-2)
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No correlation between LFUV and
size
Strong correlation between IFUV and
stellar mass
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Compact
Massive (log M*=10.5 – 11.3)
High-mass disk systems with young
stellar population
“Compact” UVLGs (IFUV>108 L๏ kpc2)
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(L๏ kpc-2)
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Low mass (log M*=9.5 – 10.7)
Mass range similar to LBGs
Large
(M๏)
Compact UVLGs
Large UVLG: SDSS J010126.56+133245.5
FUV
NUV
Compact UVLG: SDSS J005527.45-002148.6
FUV
NUV
Population Comparison (slide courtesy C. Martin)
Large UVLGs, Compact UVLGS, LBGs
Log LUV
Log rUV
AUV
M*
Log b
[O/H]
12
1.5
12
3
2
9
11
1
11
2
1
8.5
10
0.5
10
1
0
8
9
9
9
0
-1
7.5
What’s next for UVLGs?
(Multiwavelength Analysis of UVLG POPulation!)
Larger sample from SDSS DR3 and GR1
 ACS/NICMOS imaging of a subsample
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 Morphologies
 Presence
of older stars
Spitzer FIR
 Chandra
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