Barbara Catinella (MPA)on behalf of the GASS Team

GALEX Science Team Meeting. Aspen, Mar 10 2009

Barbara Catinella (MPA)on behalf of the GASS Team

GALEX Science Team Meeting. Aspen, Mar 10 2009

GALEX Arecibo SDSS Survey (GASS)GALEX Arecibo SDSS Survey (GASS)and ALFALFAand ALFALFA

GALEX Arecibo SDSS Survey (GASS)GALEX Arecibo SDSS Survey (GASS)and ALFALFAand ALFALFA

GGALEX ALEX AArecibo recibo SSDSS DSS SSurvey (GASS)urvey (GASS)GGALEX ALEX AArecibo recibo SSDSS DSS SSurvey (GASS)urvey (GASS)

Targeted HI survey: ~1000 galaxies selected from SDSS+GALEX MIS+ALFALFA footprints, 0.025< z <0.05, 10< log M✶/M⊙ <11.5

Galaxies observed down to gas mass fraction limit of 1.5%

Arecibo large program, observations started in March 2008

First statistical sample of massive galaxies with homogeneously measured M✶, SFR and gas properties

understand physical processes that regulate gas accretion and its conversion into stars in massive systems. Transition between blue and red sequences.

http://www.mpa-garching.mpg.de/GASS

D. Schiminovich (PI), B. Catinella, G. Kauffmann et al.

GASS 57017:

log M✶/M⊙ =10.54

log MHI /M⊙ =9.76

MHI /M✶= 17%

W50 = 354 km/s (uncorr. for incl)

SDSS image ARECIBO HI spectrum

1’ (39 kpc @ z=0.033)

zSDSS zHI

Single-dish HI profiles → redshift rotational velocity HI flux (→HI mass)

SDSS optical spectrum

AArecibo recibo LLegacy egacy FFast ast ALFAALFA (ALFALFA) (ALFALFA) SurveySurvey

AArecibo recibo LLegacy egacy FFast ast ALFAALFA (ALFALFA) (ALFALFA) SurveySurvey

Ongoing blind extragalactic HI survey, 7000 deg2, z<0.06 (PI: R. Giovanelli)

Started in Feb 2005, will detect >25,000 sources

Better sensitivity (8×), ang. res. (4×), spectral res. (3×) than HIPASS

MHI ~106 M⊙ out to 6.5 Mpc, MHI ~107 M⊙ out to 20 MpcDR1: Northern Virgo Cluster, 132 deg2 (Giovanelli et al. 2007) 730 detections, 69% new!! (cf. HIPASS in same region: 40)

designed to probe faint end of HIMF at z=0, will provide complete HI census

will contribute highest HI mass objects in GASS sample (~20%)

ALFALFA footprint on SDSS

GASS vs ALFALFAGASS vs ALFALFAGASS vs ALFALFAGASS vs ALFALFA

Left: GASS parent sample in region cataloged by ALFALFA (N=2795, contours). Symbols: ALFALFA detections (N=472. Red/blue: high/low inclination). Right: corresponding histograms. NUV-r is not corrected for extinction.

GASS vs ALFALFA - cont.GASS vs ALFALFA - cont.GASS vs ALFALFA - cont.GASS vs ALFALFA - cont.

ALFALFA detections (N=472, blue. Only blue sequence showed on the right panel), new GASS detections (N=41, red) and upper limits (N=20, red triangles).

NUV-r colors still uncorrected for galactic and internal extinction.

GASS-detected transition galaxiesGASS-detected transition galaxiesGASS-detected transition galaxiesGASS-detected transition galaxiesNUV-r ➞

1.5% gas fraction limit

NUV-r>4.5 incl ≤650

11223 30175 3505 38748 23445

29505

GASS transition galaxiesGASS transition galaxiesGASS transition galaxiesGASS transition galaxies

GASS 3505: “red and dead” elliptical with 44% gas fraction!!Regrowing a disk?

GASS 23445: early-type with 2% gas fraction

GASS 29505: spiral with 3% gas fraction

GASS 3505: a gas-rich, “red and dead” GASS 3505: a gas-rich, “red and dead” galaxy galaxy

GASS 3505: a gas-rich, “red and dead” GASS 3505: a gas-rich, “red and dead” galaxy galaxy

No emission linesz=0.048NUV-r=5.9

log M✶/M⊙ =10.21

log MHI /M⊙ =9.85 MHI /M✶= 44%

5″

SDSS + GALEX, 4´ (~220 kpc) field

SDSS Arecibo HI

Other GASS detections Other GASS detections Other GASS detections Other GASS detections

10″

10″

GASS 38748: z=0.047, NUV-r=6.3, log M✶/M⊙ =10.90, log MHI /M⊙ =9.16, MHI /M✶= 2%

GASS 3645: z=0.031, NUV-r=4.3, log M✶/M⊙ =10.33, log MHI /M⊙ =9.50, MHI /M✶= 15%

GASS statusGASS statusGASS statusGASS status

Final ~1000 galaxies extracted from GASS “parent sample” (N~12000). 128 already detected by ALFALFA or in Cornell HI archive.

150 hours allocated since Mar 2008, mostly in 2009

Observations done from MPA by BC and S. Fabello; more observers (including J. Wang, K. Zhang, J. Lemonias, S. Moran + others) to be trained in 2009

99 galaxies targeted: 41 detected, 20 upper limits, others in progress

Follow-up programs

optical long-slit spectroscopy (PI: S. Moran; 6.5m MMT, 3.5m Apache Point) for ~300 GASS targets. 54 resolved spectra obtained since Oct 2008.

VLA proposal to map 3 transition galaxies submitted in Feb 2009

CO (IRAM): small proposal + large program to be submitted in 2009