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Previous GI Cycles

Cycle 4 Information

ID Investigation Surveys/Fields/# Type* Science Team Contact Description of Investigation

A1

Number Counts of GALEX Sources.

Classification & star-Counts of Galactic objects in the GALEX surveys and extinction maps

 

 

AIS/1000

MIS/100

DIS/5

WSS/100

MSS/10

DSS/2

1

Xu

Donas

Bianchi

The surface density of GALEX sources as a function of the UV flux will be determined, with the incompleteness and the contamination of false sources corrected. Stars and galaxies will be separated using their UV/optical colors, empirically and in reference to model SEDs of all types of objects. This will be confirmed using the spectroscopic data taken in the WSS/MSS/DSS surveys. The galaxy counts will be compared to those in the literature. The field to field variation of galaxy counts due to cosmic variance will be investigated. These will set new constraints to galaxy evolution models, and to the contribution of galaxies to the cosmic UV background. Using AIS, MIS, DIS, WSS, MSS and DSS overlapping SDSS DR1 and DR2.

A2

Local UV Luminosity Function

 

 

MIS2DF

MISDR1

AIS

1

Wyder

Treyer

Matching of the GALEX AIS data with catalogs from available low-redshift surveys, we create FUV and NUV magnitude-limited redshift samples. We determine FUV and NUV luminosity functions and compare the results with previous measurements of the UV luminosity function from the FOCA experiment. UV LF vs. SED, mass, spectral-morphological type, density, etc.

A3

Evolution of UV Luminosity Function with z

 

 

DIS/NGPDWS

DIS/CDFS

DIS/GROTH

DIS/VVDS22H

DIS/XMMLSS

1

Schiminovich

Arnouts

 

Using the GALEX deep Imaging survey, the luminosity function is computed as a function of the redshift from existing spectroscopy, and z-selection from Ly-break and photometric redshift techniques.

Use AIS & DIS with optical spectroscopic and photometric data to constrain how the evolution of the luminosity function with redshift depends on the galaxy type, metal content, local density, .)

A4

Angular/Spatial correlation function

 

Correlation between UV luminous galaxies and large scale mass distribution

 

x(r,z) for 0 < z < 2

 

 

 

AIS

MIS
DIS

WSS

MSS

DSS

 

1

Budavari

Arnouts

Small

Schiminovich

Refregier

Determine the angular and spatial correlation functions in the local universe (z~0) and from z~0 to z~1 using redshift surveys in the visible and photometric redshift techniques.

 

Use AIS & DIS with optical spectroscopic and photometric data to constrain how the evolution of the correlation function with redshift depends on the galaxy type, luminosity, metal content, local density.

 

We will measure the spatial two-point correlation function of galaxies with measured redshifts in the GALEX spectroscopic surveys.

 

We will determine the bias parameter and galaxy-mass cross-correlation coefficient using deep GALEX measurements of galaxies at 0.5<z<1.5 and HST and CFHT measurements of weak lensing by large scale structure.

 

A8

Luminous UV Galaxies Lyman Break Analogs.

FUV and NUV dropout sources

 

AIS

MIS
DIS

NGS

WSS

1

Small

Martin

Heckman

Seibert

Schiminovich

Milliard

Hoopes

 

We study the properties of the most UV luminous star forming galaxies (L_UV > 10^10) in the local and distant Universe found by GALEX using all available corollary data. These galaxies may be analogs to Lyman Break Galaxies at high redshift. Using GALEX UV images and spectra and optical drift-scan spectra, we will perform a detailed study of local galaxies selected by their UV luminosity in analogy with z ~ 3 Lyman-Break samples. We will focus on star formation estimates, dust extinction, and metallicity.

 

Apply Steidel's z~3 LBG selection technique to GALEX FUV and NUV dropouts (vs u g r i .) respectively at z~1 and ~2 to track the evolution of this population of galaxies with as close as possible selection criteria.

B1

The Dust Attenuation Law in UV-selected galaxies.

 

AIS

MIS

DIS

UDIS

1

Seibert

Heckman

Charlot

Determine the optimum prescription for correcting the UV emission in UV-selected galaxies for the effects of internal dust attenuation. This uses UV (Galex), optical (SDSS, NOAO DWF, EIS, etc.), and near-IR (2MASS, NOAO DWF, SIRTF) photometry of UV-selected galaxies as input and seeks to recover the detected far-IR reradiated emission (IRAS; SIRTF) through the use of model galaxy SEDs that incorporate a range of star-formation histories and a realistic treatment of dust.

B2

Comparing the properties of UV vs. far-IR selected samples of galaxies.

AIS

MIS

DIS

UDIS

1

Buat

Xu

Donas

Iglesias

Compare the properties of galaxies selected by far-IR vs. UV flux. Determine the distributions of UV dust attenuation, star formation rate, metallicity, galaxy mass, Hubble type, etc. and compare these for the two samples. This will utilize Galex imaging data to

study both local and distant galaxies. IRAS and SIRTF will be used to select the far-IR samples, combined with ancillary SDSS data (for low-redshift) together with a variety of deep optical and near-IR imaging and spectroscopy (z ~ 1).

B3

A Joint UV/Far-IR Measure of the Cosmic Star-Formation Rate

AIS

MIS

DIS

UDIS

1

Martin

Hoopes

Heckman

 

We will use IRAS and GALEX to determine the joint FIR/UV luminosity function in the local universe and the corresponding star formation rate. This investigation will be extended to z ~ 1 using the deepest Galex imaging data together with far-IR data from SIRTF and a combination of photometric and spectroscopic redshifts (CDF-S, NOAO-DWFS, COSMOS).

C1

The starburst parameter distribution at z=0

MIS/SDSS

AIS/SDSS

1

Salim

Rich

Kauffmann

Charlot

Using the Galex/SDSS (DR1) matched data set, determine the starburst age distribution for ~10^5 galaxies at z=0.

 

C2

Starburst history at z>0.5

DIS

DSS

1

Martin

Using the Galex/Deep optical photometry & spectroscopy matched data sets, determine the starburst age distribution for ~10^5 galaxies at z>0.5.

C3

Star formation metrics

AIS

MIS

(/various surveys;

IRAS, FIRST,SDSS)

1

Salim

Rich

Correlate the Galex measurement of the star formation rate of galaxies with other major star formation metrics, including H-alpha, 60 micron, radio continuum, X-ray.

C4

UV luminosity vs. HI (and HI+H2) mass and HI-measured properties

AIS

MIS

DIS

NGS+cluster

1

Schiminovich

Johnson

Using a large sample (>1000-10000 galaxies) from available HI surveys (HIPASS, HIJASS, Arecibo/Effelsburg/Green bank surveys + volume limited synthesis imaging samples) study M_HI/L_UV (and gas density/surface brightness) vs. galaxy properties, environment with the goal of understanding how gas excess or deficiency relates to recent star formation history in galaxies. Use HI survey data to measure the bivariate UV luminosity vs. HI mass function (and/or trivariate UV/HI mass/HI width). Combine with CO->H2 where available. Investigate how/whether UV combined with other observables can be used as "gas mass" estimator in high redshift samples.

C5

UV/radio(/SIRTF) correlation in the Phoenix deep radio

survey field.

PHOENIX field

1

Treyer

Schiminovich

Use the GALEX observation of the PHOENIX survey to perform a comparison of the UV and radio continuum emission.

C6

Statistically derived properties of galaxies from SEDs

AIS/SDSS

MIS/SDSS

DIS/NGPDWS

DIS/CDFS

DIS/GROTH

DIS/VVDS22H

DIS/XMMLSS

1

Budavari

Szalay

Rich

Using galaxies with measured redshifts and physical parameters as a training set, determine photometric redshifts, reddening, stellar mass, etc. for a large sample of galaxies

C7

Analyzing the z=0 Galex/SDSS dataset as a high redshift dataset

AIS/SDSS

MIS/SDSS

DIS/deep optical

1

Rich

Salim

Budavari

 

Treating the GALEX/SDSS and GALEX/deep data as if they were high redshift photometric datasets (and using the same methods), derive photo-z, stellar masses, reddening, and star formation rate at z=0 and compare to results determined in C1.

C8

Connecting the dots: reconciling starburst history in galaxies with galaxy statistics

AIS/SDSS

MIS/SDSS

DIS/deep optical

1

Kauffmann

Martin

 

Starburst history in individual galaxies must be consistent with the statistics of galaxies in bursting, quiescent star formation, or non-star-forming states.

This investigation of 0<z<1.5 galaxies determines whether the individual and collective histories are consistent.

C9

The Star Formation History vs. Galaxy Properties

AIS

MIS

DIS

MSS/DSS

1

Martin

Schiminovich

Heckman

Milliard

Synthesis analysis: the star formation density history of the universe over 0<z<1.5-2 using GALEX UV, Far IR, and optical redshifts (photo and spectroscopic). Using the largest sample possible, subdivide SF History by galaxy properties: stellar mass, gas mass, star formation rate, specific star formation rate, SED, morphology, SF radius, stellar radius, recent starburst history, local galaxy density, extinction, SF mode [starburst, quiescent], presence of companions, etc.

D1

Recent star formation and study of the extinction in nearby resolved galaxies

NGS/NGA_

(

WLM, NGC0205, M31_*,

LGS3, IC1613, M33_*,

Phoenix, LeoA, SextansB,

NGC3109, Antlia_Dw,

SextansA, NGC6822,

Pegasus, NGC0024,

NGC0055, NGC0247,

NGC0253, NGC0300,

NGC0404, NGC1156,

NGC1569, NGC2366,

NGC2403, HolmbergII,

DDO053, UGC4483,

HolmbergI, NGC2976,

M81+M82, NGC3077,

M81DwB, IC2574,

NGC4236, UGCA292,

DDO154, NGC4826,

NGC5253, NGC6789,

UGCA438, NGC7793,

NGC0628, NGC0891,

NGC0925, NGC1313,

NGC2915, NGC4258,

NGC4736, M51, M83,

M101, NGC5474, HCG092,

NGC1399, NGC2903,

NGC3079, NGC4631,

NGC5055, Cen A

)

1

Bianchi

Thilker

Wyder

Seibert

Madore

Properties of young clusters and massive stars in nearby (resolved) galaxies will be derived by multi-scale, multi-wavelength photometry using GALEX UV imaging and corollary data at other wavelengths. We will publish a comprehensive catalog of UV sources matched to optical photometry, on different spatial scales. For young stellar clusters and start forming regions in these galaxies we will concurrently determine extinction, age and mass by comparison with synthetic model magnitudes. In Local Group galaxies, we will also measure the effective temperature and extinction for individual massive stars from the multi-band photometry. Our census of star forming regions in each galaxy will be used to constrain the recent star formation history (SFH) and initial cluster mass function (CMF). The cluster population, SFH, and CMF will be analyzed as a function of Hubble type, galaxy mass, and galactic environment with a view toward galaxy evolution. For the few nearest galaxies, the UV extinction will be also determined from the FIR (as measured by IRAS) to UV ratio, while the spectral slope will be determined from the FUV-NUV colors.

D2

IRX-beta in resolved galaxies

NGS/NGA_(galaxies in common with:

- SIRTF SINGS+GTO >1'

)

1

Madore

Seibert

Gil de Paz

Using GALEX imaging data for the NGS galaxies in common with the SIRTF SINGS Legacy program and SIRTF GO programs we determine how the IRX-beta relationship varies with location in nearby galaxies.

D3

Extended UV emission in nearby galaxies

AIS

MIS

NGS/NGA_*

NGS/NGRG_*

1

Seibert

Wyder

Schiminovich

Gil de Paz

Thilker

Bianchi

Neff

The origin of the extended UV emission recently discovered by GALEX in the outskirts of grand-design spirals and in tidal tails and bridges will be analyzed. In particular we will determine the SFR properties of these regions and the contribution they make to the luminosity and stellar-mass evolution of galaxies.

D4

Radial dependence of the dust attenuation in resolved galaxies

NGS/NGA_(galaxies in common with:

- IRAS larger than 6'

- ISOPHOT >2.5'

- SIRTF SINGS+GTO >1'

)

 

1

Boissier

Boselli

Buat

Madore

Gil de Paz

 

We determine the radial dependence of the dust attenuation in resolved galaxies by combining the GALEX FUV and NUV data with drift-scanning optical spectra, 2MASS near-infrared images and FIR data from IRAS/ISO/SIRTF. The dust attenuation provided by the FIR/UV ratio will be compared with the values derived from the Balmer-line decrement and the slope of the UV continuum (beta). These profiles will be compared with the gas and metail-abundance profiles. Finally, we intend to determine the dust attenuation law both from the intregrated properties of the galaxies and as function of the galactocentric distance.

D5

The starburst history of resolved galaxies

NGS/NGA_*,

NGS/NGRG_*,

MIS/MISDR1_(

00470_0603, 00560_0453,

03332_0447, 03421_0551,

03423_0445, 03473_0440,

03521_0440, 03669_0441,

03721_0439, 10094_0352,

10217_0612, 10276_0355,

10292_0612, 11087_0631,

11318_0632, 12637_0277 .

13206_0516, 13257_0517,

13649_0334, 13700_0522,

13885_0523, 13947_0523, 1

3951_0292, 13953_0336,

14019_0337, 17274_0429,

17498_0428, 17881_0664,

17930_0665, 17931_0665,

18127_0407, 18359_0454,

18416_0455, 18474_0455,

18474_0455, 18848_0459,

24220_0477, 24276_0267,

24310_0266, 27124_0460,

29519_0654, 33654_0586,

33677_0588, 33682_0585

33710_0585, 33712_0584

33741_0533,33742_0533

33760_0539,33761_0538

33777_0530,33791_0310

)

1

Rich

Salim

We investigate the starburst age/mass history of resolved galaxies imaged in the NGS and MIS surveys, and relate it to a large scale study of the starburst age distribution of SDSS galaxies. Galex and optical images will be fit

pixel-by-pxiel with Bruzual-Charlot models to derive the integrated mass in recently formed stars and the age distribution and extinction of this recent star formation. The result will be compared with a similar modeling of the integrated light of the galaxies.

 

 

D6

Multi-wavelength morphology of resolved galaxies

NGS/NGA_*

NGS/NGRG_*

MIS/MISDR1_(

00470_0603,00560_0453,

03332_0447,03421_0551,

03423_0445,03473_0440,

03521_0440,03669_0441

03721_0439,10094_0352

10217_0612,10276_0355

10292_0612,11087_0631

11318_0632,12637_0277

13206_0516,13257_0517

13649_0334,13700_0522

13885_0523,13947_0523

13951_0292,13953_0336

14019_0337,17274_0429

17498_0428,17881_0664

17930_0665,17931_0665

18127_0407,18359_0454

18416_0455,18474_0455

18474_0455,18848_0459

24220_0477,24276_0267

24310_0266,27124_0460

29519_0654,33654_0586

33677_0588,33682_0585

33710_0585,33712_0584

33741_0533,33742_0533

33760_0539,33761_0538

33777_0530,33791_0310

)

1

Thilker

Bianchi

Burgarella

Madore

Lauger

Buat

Gil de Paz

Boissier

We quantify the multi-wavelength morphology of a representative sample of galaxies covering the range of Hubble types, thereby providing a characterization benchmark at z=0. We will use GALEX NGS and MIS images, SDSS and 2MASS data for all objects. We will also identify a more physical classification sequence that can be used as an evolving comparison sequence with higher redshift galaxies.

D7

UV observations of Local Group Dwarf Irregular galaxies

AIS

NGS/NGA_(NGC6822,

IC1613, Phoenix, Pegasus,

WLM, LGS3, LeoA)

 

1

Wyder

Rey

Rich

We investigate the UV properties of selected Local Group dwarf irregular galaxies. We compare the structure of the galaxies in the UV with that in the optical, HI and infrared to understand the distribution of young stars with respect to the gas and older stars in these systems. Integrated UV fluxes of the HII regions and OB associations are used to determine ages and extinctions for individual regions within the galaxies. For the nearest galaxies, we use the resolved stars to place constraints on the recent star formation histories.

D8

UV properties of Luminous and Dwarf Blue Compact galaxies

AIS

MIS/MISDR1_03669_0441

NGS/NGA_HS0822p3542

NGS/NGA_IZw18

NGS/NGA_Mrk1450

NGS/NGA_NGC1705

NGS/NGA_NGC2537

NGS/NGA_NGC2915

NGS/NGA_NGC3125

NGS/NGA_NGC4861

NGS/NGA_NGC6789

NGS/NGA_SBS0335m052

NGS/NGA_Tol0618m402

NGS/NGA_Tol2

NGS/NGA_Tol65

NGS/NGA_VIIZw403

DIS (Groth)

1

Gil de Paz

Madore

Yi

Milliard

Szalay

Using GALEX imaging data from AIS, MIS, NGS, and DIS, for a sample of known Luminous and Dwarf Blue Compact galaxies, we determine (1) the recent star formation rate, (2) the spatial distribution of star formation sites (in objects closer than ~70 Mpc), and (3) the extinction. We also investigate the role of this population in the galaxy formation and evolution from intermediate redshifts to the present.

 

D10

 

*

Jet-triggered star formation in

NGS/NGA_Centaurus_A,

M87, Pictor-A,

 

1

Schiminovich

Martin

Xu

Neff

We explore the origin and nature of UV emission associated with radio jets in nearby radio galaxies.

 

 

D11

UV survey of the Magellanic Clouds

LMC:

8x8deg area centered at:

RA(J2000)=05h19m04s

DEC(J2000)=-68d18'33''

 

SMC:

5x5deg area centered at:

RA(J2000)=00h58m23.4s

DEC(J2000)=-72d49'25''

 

Typical exposure = 800-1000 sec

2

Bianchi

Thilker

Byun

Lee

The full extent of the Magellanic Clouds will be surveyed at a depth of 2e-16 ergs/cm2/s/A (800 sec exposure) to catalog and study young stars, stellar clusters and the extinction in these benchmark galaxies. We will provide on-line products for these GALEX Legacy data: mosaic UV images and photometric catalogs across the entire galaxies, in addition to estimates of extinction and preliminary object classification for detected UV sources (eventually with

information on variability). Our classification technique will be enhanced via cross-correlation with existing catalogs of known objects. We will photometrically derive physical parameters for the hot stellar objects (T_eff and extinction) and determine mass, luminosity, size, age, and extinction for all detected star forming clusters. The recent SFH and initial cluster mass function will be

inferred both globally and within localized areas.

 

Given the Legacy scope of these observations and bright star avoidance considerations, only about 10% of the LMC and SMC surveys will be released as part of DR1, possibly at lower-than-final exposure times. We encourage GI investigation of diverse topics using this exploratory database, in addition to proposals for significantly deeper observations of localized regions in the Clouds. The GALEX MC surveys will be obtained over multiple epochs, eventually enabling studies of variability. However, GIs need to be aware that such work may not be feasible using the DR1, since it will probably include only one epoch.

D12

UV luminosity and color profiles of the dwarf elliptical galaxy M32

NGS/NGA_M31_*

1

Gil de Paz

Madore

Rich

Seibert

Bianchi

Lee

Sohn

M32 has been widely used as template for the study of stellar populations in elliptical galaxies. For that reason, the findings from the UIT regarding the presence of an inverted FUV-B color gradient in M32 with respect to the majority of the elliptical galaxies need to be checked. GALEX data along with a careful analysis of the contamination of the galaxy background from the M31 disk will confirm (or rule out) the results from the UIT.

D13

Spectrophotometric study of M83

NGS/NGA_M83

 

1

Boissier

Gil de Paz

Madore

GALEX FUV and NUV and ground-based broad- (UBVRJHK) and narrow-band (Halpha, Hbeta) imaging data will be used to constrain models of the luminosity and chemical evolution of M83 at different radii. In particular we will analyze (with spatial resolution) the applicability of the different SFR estimators and dust-extinction recipes in resolved galaxies.

D14

Superwinds from Starburst Galaxies

NGA_M82

NGA_NGC0253

NGA_ NGC1482

NGA_ NGC2146

NGA_ NGC3079

NGA_ NGC3628

NGA_ NGC4631

1

Hoopes

Heckman

We will analyze the spatial correlation of extra-planar UV filaments with H-alpha and X-ray emission in the starburst-driven outflows in a small sample of nearby edge-on starburst galaxies in the NGS/NGA. M82 and NGC253 are in the G1 sample and five more are in G2. We will use various models for shock-heated and photoionized gas to try to determine the origin of the UV light (nebular line and continuum emission or dust-scattered stellar continuum).

 

E1

Lyman continuum escape fraction and Lyman alpha emission (spectroscopic, and imaging)

UDIS

DIS

MIS

WSS

MSS

DSS

1

Deharveng

Friedman

Martin

Small

 

This investigation uses several methods to search for and study the Lyman continuum radiation escaping from galaxies. We will stack GALEX spectra of galaxies of redshift between 0.55 and at least 0.85 to determine the Lyman continuum flux and escape fraction. We will also measure the shape, equivalent width, and velocity offset of the Lyman alpha emission line in the composite spectrum. We will stack GALEX FUV and NUV images at the locations of known z~1, ~2, and ~3 galaxies to determine the Lyman continuum flux and escape fraction vs. redshift. As survey depth and S/N permit, we will stack less, use finer bins for redshift and other parameters, and study brighter galaxies individually. We will observe DIS fields that include a high-z QSO visible in the rest UV to search for Lyman continuum emission in high redshift galaxies possibly visible through an unusually clear line of sight.

E2

Lyman alpha emission from individual galaxies

WSS/DR1/2dF

MSS/DR1/2dF

DSS/DR1/2dF

1

Buat

Burgarella

Deharveng

Schiminovich

The objectives of this program are:

1) Statistical analysis of the density of Lyman alpha emitting galaxies as a function of redshift.

2) Multi-parameter analysis of extinction, star formation rate, morphology, metallicity, etc. using corollary data (visible spectroscopy and FIR whenever possible).

E3

Galaxy clusters and compact groups: the environmental effects on galaxy evolution and star formation

NEARBY CLUSTERS:

 

COMA:

COMA_SPEC

COMA_MIS

AIS (5 deg^2 centered on the cluster)

 

A1367:

A1367_SPEC

A1367_MIS

AIS (5 deg^2 centered on the cluster)

 

VIRGO:

VIRGO_SPEC_1 & co-located MIS

VIRGO_SPEC_2 & co-located MIS

NGS + MIS + AIS: all fields within 12h<RA<13h; 0<dec<20deg

 

Reference sample of isolated galaxies:

AIS + MIS in the region 11h30m<RA<13h30m; 18deg <DEC<32deg

 

COMPACT GROUPS:

 

AIS (Hickson's catalog)

NGS/NGA_HCG092

 

DISTANT CLUSTERS:

 

AIS (A0085, A0119, A0151, A0168, A0496, A0514, A2734, A3112, A3122, A3128, A3158, A3825)

 

MIS (A2390,A0520, MS1231+15, CL0016.5+1654,

MS0451-03, MS1358+62, MS1621+26, MS0906.5+1110,

MS1008.1-1224, CL3C295, CL0024+1654, CL0909+4408, CL0939+4713,

CL0303+1706,

CL1601+4253, CL0016+1609)

 

DIS (MS1054‑03,

RXJ0152-13)

 

MIS and DSS portions that overlap with SDSS

1

Boselli

 

 

 

Donas

 

Iglesias

 

Morrissey

 

Rich

 

 

We will study the effects of the environment on galaxy evolution and star formation, by comparing the statistical multi-wavelength photometric and spectroscopic properties of galaxies spanning the whole range of morphological type and luminosity (from giant to dwarf ellipticals, Im and BCD), belonging to various environments (clusters, compact groups) at different redshifts. We will compare findings with those of other GALEX investigations for field galaxies, controlling for selection criteria. GALEX imaging and spectroscopic data, combined with those available at other wavelengths (from UV to radio continuum), will be used to:

 

- Study the spatial distribution of the UV flux vs redshift and cluster/group properties.

 

- Study the SED of cluster and compact group galaxies, determine their UV luminosity function, and compare them to those of field galaxies.

 

- Study the star formation history of cluster and group members using different tracers of the recent (Halpha, UV) and past (UV to near-IR SED) star formation activity, with particular attention to the Butcher-Oemler effect.

 

- Study the dust extinction properties and the extinction curve of cluster galaxies using three independent tracers, the Halpha/Hbeta Balmer decrement, the FIR/UV ratio, and the shape of the UV spectrum.

 

- Determine the effects of interactions on the morphology of galaxies.

 

- Analyze the multi-wavelength statistical properties of volume limited, complete samples of cluster and group galaxies including all morphological types.

E5

Survey of Damped Lyman Alpha absorbers

WSS, MSS, DSS

 

AIS & MIS with SDSS overlap;

 

DIS: GROTH, VVDS, CDF-S

1

Deharveng

Milliard

The GALEX spectroscopic surveys will provide a homogeneous sample of DLAs and sub DLAs, relevant to the neutral gas and metal content in the Universe at 0.2 < z < 1.1, and to the nature of intervening galaxies. Photometric redshift techniques will help classify the objects. We expect to find about 20 new DLAs. The same data will improve the low redshift Lyman limit system sample. In addition, matching GALEX imaging surveys in spectroscopic QSOs samples, using photometric redshift techniques, and subsequently following up in fields with optical photometry, is an efficient means of detecting UV-bright QSOs with MgII absorbers, which are well pre-selected candidates for low redshift DLAs. This second approach should provide several dozen DLAs in fields with currently available spectroscopy.

E6

Cross-correlation UV- visible in the local and z~1 Universe

AIS & MIS with SDSS overlap;

 

DIS: GROTH, VVDS, CDF-S;

 

WSS, MSS, DSS

1

Budavari

Milliard

We will study the cross-correlation of the GALEX-detected light distribution and visible light distribution in galaxies as a function of redshift. This provides insight into the links between star formation activity and large-scale mass distribution, for which some models predict a fast change of the cross-correlation at z < 1. This subject has both spectroscopic and imaging aspects. Spectroscopy permits a 3D approach that may be more powerful. This work is closely connected to studies of UV-property evolution vs. local density in clusters.

E7

UV attenuation curve in star forming galaxies

WSS, MSS, DSS and corresponding imaging fields

1

Buat

Burgarella

Boselli

We will study extinction in galaxies between 1350 A and 2800 A in order to determine extinction curves for various types of galaxies, similar to Calzetti's attenuation law for starburst galaxies. The UV spectra will be analyzed together with tracers of the dust extinction like the Halpha/Hbeta Balmer decrement and the FIR to UV flux ratio. These data will be used to calibrate empirical attenuation laws at a resolution of order 100A.

F1

Lyman alpha emission

From the IGM

MSS/COSMOS/VIRMOS

DSS/CDFS/NGPDWS

1

Johnson

Martin

Deharveng

Schiminovich

Perform unbiased and targeted (w/priors) searches for Lyman alpha emission from the IGM either through direct detection or cross-correlation with group, filamentary, UV luminous objects, and other structures with 3-d distributions determined from redshift surveys. Compare IGM to the local UV luminosity density.

F2

S/N UV light curves

DIS, repeated observations

 

2

Schiminovich

(Pipeline)

Welsh

Martin

Use catalogs and difference images to measure UV light curves of S/N in deep fields. Trigger follow-up with ground based telescope. Prove the UV deficit in Type Ia and UV-visible colors of other types

F3

Look-back time evolution of UV flux from elliptical galaxies in 0.0 < z < 0.4

Abell clusters (# of orbits):

A119 (5) , A2670 (10),

A3330 (10), A098 (10),

A216 (10), A389 (15),

A951 (15), A2235 (15),

A2218 (20), A2192 (20),

A2390 (20), A2111 (20),

A1952 (20)

 

DIS

1

Lee

Rich

Deharveng

Bianchi

Investigate the origin of UV flux from the early-type galaxies. Redshift evolution of FUV - V color within the detection limit of GALEX (z < 0.3-0.4). Comparison of UV flux vs. metallicity/ velocity dispersion correlations in remote clusters with those for the nearby systems.

 

F4

UV properties of

nearby elliptical

galaxies & bulges

NGS

MIS

AIS

1

Rich

Lee

Deharveng

Bianchi

UV flux and its correlation with metallicity/velocity

dispersion, radial UV color gradients within nearby Es/bulges compared with metallicity gradients, UV color-magnitude relations, UV surface brightness fluctuations as population indicator. Ultraviolet light from the oldest stars in galaxies is expected to evolve rapidly with redshift and this UV light must be distinguished from low levels of star foramtion in spheroidal galaxies, which must increase with redshift.

F5

UV properties of

globular clusters in

nearby galaxies

NGS (M31, M33, Cen A, gEs in Fornax & Virgo)

1

Lee

Rich

Bianchi

We will use UV flux from globular clusters as a clock to study the formation history of Local Group Galaxies (M31, M33) compared to our own. We will also attempt to detect UV brightest globular clusters in Cen A and in gEs in Fornax and Virgo clusters.

 

F6

The extragalactic

ultraviolet background

AIS

DIS

2

Martin

Deharveng

Schiminovich

i) search of the parameters ( latitude, airglow, etc)

that explain variations of the average UV background emission from directions to directions

ii) search for the presence of features in the

background within deep fields and interpretation in terms of dust scattering/absorption and other phenomena

iii) constraints on the integrated emission from galaxies and contribution from the intergalactic

medium.

F9

Hot White Dwarfs

DIS

MIS

AIS

DSS

MSS

WSS

2

Welsh

Bianchi

Photometric and spectroscopic analysis of known hot white dwarfs

F10

Search for Variable and Transient Sources in Time-Resolved Data

 

DIS

MIS

AIS

2

Welsh

Wheatley

Search all time-resolved GALEX data for variable and transient sources

F14

Symbiotic Stars

AIS/WSS

MIS/MSS

DIS/DSS

2

 

Welsh

Wheatley

Analysis of symbiotic star UV emission line spectra and their variability

F12

Metal Deficient Stars

AIS

MIS

DIS

2

Laget

Rich

Rhee

Calibrate UV colors against known metal contents, then trace distribution of candidate metal-deficient stars at high galactic latitude.

F7

UV H-R diagrams of selected Galactic globular clusters

AIS (M2, w Cen, M3, M10, M13, M15, M53, M68, M72, M79, M92, NGC 288, 362, 1851, 2808, 5466, 6752, 6791)

2

Rich

Lee

Laget

 

UV properties of hot stars in Galactic globular clusters. Hot HB stars and comparison with HB evolutionary tracks.

 

F8

QSO counts and

Luminosity function at

z > 0.3 from

photometric redshifts, SED Evolution

AIS & MIS with SDSS overlap

DIS : GROTH, VVDS, CDF-S

WSS, MSS, DSS, FIRST/X-ray(RASS)

2

Forster

Arnouts

A homogeneous sample of QSO candidates will be assembled, as a by-product of the objects classification with photometric redshifts

techniques in the number counts work. Such a sample is relevant to studies of the fraction of star formation harbored in QSOs, the evolution of the EUV rest-frame of QSOs, and provides probes of the intergalactic medium opacity. The sample will complement and can be checked against the one derived from identification in QSOs catalogs. Verifications of the classification in the GALEX spectroscopic samples and QSOs catalogs will be made. Preliminary tests on two IR0.1 MIS fields overlapping SDSS, shows the technique is

able to retrieve all SDSS QSOs at bright magnitudes, and suggest that twice as many are present in the fields.

 

The evolution of the spectral energy distribution of QSO's will be undertaken using a homogeneous sample of QSO's detected in GALEX surveys. This will extend studies using the CIV emission line and FeII emission complexes down to low redshift to search for evolution in QSO spectral properties. The shape of the faint end of QSO luminosity function will be investigated to confirm a flattening found in optical studies of low redshift QSOs.

F8

Mass of black holes in low redshift AGN and host galaxy-AGN

interactions

NGS/MSS/DSS SDSS/2df/2MASS

2

Forster

We investigate the the MgII 2800 emission line as a useful diagnostic of black hole masses in AGN. GALEX will provide UV measurements of many thousands of low redshift AGN as well and will aid an investigation into the link between starburst and low-luminosity AGN activity.

F9

Large scale structure and QSO clustering

MIS/DIS

 

2

Forster

The GALEX surveys will provide a catalog of many tens of thousands of QSOs that will allow the mapping large scale structure on very large scales and, combined with the GALEX investigations into the star formation history of the universe out to z<2, will provide information on the environments around QSO's.

F10

Far-UV imaging of the Galactic bulge to study UV-bright stars

FUV MIS imaging of fields with |b|<12 and |l|<10

2

Rich

We image fields in the Galactic bulge using the FUV only, to identify and characterize UV bright stars in FUV-V. We determine the distribution and luminosities of these stars and explore their feasibility as a possible explanation for the UV rising flux in early-type galaxies.

* Investigation Types: 

Type 1 These science investigations, in association with the indicated targets/surveys, form the primary science objectives of the GALEX mission.  Proposals duplicating these investigations will not be awarded new observations or funding.  Approximately 10% of each survey's data will be available as part of Data Release 1 on 1 Oct 2004, or is already available as part of the Early Release Observations. Archival proposals using this data for other investigations are welcome, as long as they do not duplicate GALEX Science Team investigations described above. 

Type 2 These are investigations underway by members of the GALEX Science Team using the primary survey data, but do not form part of the primary science investigation of the GALEX Science Team.  They are listed for informational purposees only.  These science topics are not reserved in any way by the GALEX Science Team, and they may be the subject of  Guest Investigator proposals, either for archival investigations, or for new observations (if existing / planned GALEX survey data is not sufficient for the investigation; e.g. the GI proposal requires a larger area, spectroscopy instead of imaging, deeper exposure, etc.).

 

 

 


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