The e-MERGE Legacy Survey The e-MERGE Legacy Survey – an e-MERLIN+JVLA Ultra-Deep Survey– an e-MERLIN+JVLA Ultra-Deep Survey

Tom Muxlow JBCA ManchesterTom Muxlow JBCA Manchester

Ian Smail, Ian McHardy & the Ian Smail, Ian McHardy & the e-e-MERGE MERGE ConsortiumConsortium

EVN Symposium - Cagliari 7EVN Symposium - Cagliari 7thth October 2014 October 2014

,

High-resolution mapping of the µJy radio source population

How does the star-How does the star-formation density formation density vary with cosmic vary with cosmic epoch ?epoch ?

What are the best What are the best extinction-free extinction-free measures of star-measures of star-formation rate at high formation rate at high redshift ? redshift ?

Radio continuum Radio continuum luminosity correlates luminosity correlates with far-infrared with far-infrared emission, - both of emission, - both of which trace star which trace star formation in galaxies.formation in galaxies.

Star-formation at Star-formation at High RedshiftHigh Redshift

Radio is an excellent tracer of (obscured) star-Radio is an excellent tracer of (obscured) star-formationformation

Extinction-free !!Extinction-free !!

–– but need to remove AGN contaminationbut need to remove AGN contamination –– requires spectral information & high angular requires spectral information & high angular

resolutionresolution–– can also study AGN - star-formation feedbackcan also study AGN - star-formation feedback

Radio is an excellent tracer of (obscured) star-Radio is an excellent tracer of (obscured) star-formationformation

Extinction-free !!Extinction-free !!

–– but need to remove AGN contaminationbut need to remove AGN contamination –– requires spectral information & high angular requires spectral information & high angular

resolutionresolution–– can also study AGN - star-formation feedbackcan also study AGN - star-formation feedback

Multiple tracers of star-Multiple tracers of star-formation rate available – but formation rate available – but many are subject to extinction many are subject to extinction at high zat high z

Total amount of star-formation Total amount of star-formation missed from UV surveys at such missed from UV surveys at such high redshifts remains high redshifts remains uncertain…uncertain…

Multiple tracers of star-Multiple tracers of star-formation rate available – but formation rate available – but many are subject to extinction many are subject to extinction at high zat high z

Total amount of star-formation Total amount of star-formation missed from UV surveys at such missed from UV surveys at such high redshifts remains high redshifts remains uncertain…uncertain…

Star-formation history from Far-UV + IR high redshift samples Star-formation history from Far-UV + IR high redshift samples (Left)(Left)

Far-UV (Upper Right) Far-UV (Upper Right) IR (Lower Right)IR (Lower Right)

UV data critical in constraining s-f rate density models at high UV data critical in constraining s-f rate density models at high redshiftredshiftBouwers et al (2012)Bouwers et al (2012) Schenker et al (2013)Schenker et al (2013)

Madau & Dickinson Madau & Dickinson (2014) (2014)

10’10’10’ L-Band field centred on GOODS-N10’ L-Band field centred on GOODS-N92 sources >40µJy. Observed 1996 - 1998 92 sources >40µJy. Observed 1996 - 1998 High resolution imaging can morphologically distinguish AGN & SFHigh resolution imaging can morphologically distinguish AGN & SF<70µJy population dominated by s-f galaxies typically at z<1.5<70µJy population dominated by s-f galaxies typically at z<1.5 15’ diameter contiguous combination image15’ diameter contiguous combination image178 sources imaged with flux densities >5178 sources imaged with flux densities >5σσ (beam corrected) (beam corrected)

Original MERLIN+VLA study of faint radio sources in Original MERLIN+VLA study of faint radio sources in GOODS-NGOODS-N

J123634+621241 z=1.219 J123634+621241 z=1.219 starburststarburst

False Colour: WFPC 2 Contours: False Colour: WFPC 2 Contours: RadioRadio

CI 10µJy/bm, 1CI 10µJy/bm, 1σσ=3.3=3.3µµJy/bmJy/bm

Muxlow et al Muxlow et al 20052005

LAS peaks ~1.5” LAS peaks ~1.5”

Wrigley et al in prep.Wrigley et al in prep.

Muxlow et al 2005Muxlow et al 2005

See poster See poster by Wrigley by Wrigley et al et al

90% complete to 20µJy

e-MERGE Surveye-MERGE Survey

full sampling of AGN & s-f galaxy radio luminosity full sampling of AGN & s-f galaxy radio luminosity function to z~5 function to z~5

>60 CO-Is from 9 countries>60 CO-Is from 9 countries

Tier 0: Tier 0: Ian Smail [Durham], Ian Smail [Durham], Tier 1: Tier 1: Tom Muxlow [Manchester] Tom Muxlow [Manchester] (Deep-(Deep-narrow – 0.2 sqnarrow – 0.2 sqοο) Tier 2: ) Tier 2: Ian McHardy [Southampton] Ian McHardy [Southampton] (via PATT (via PATT or SuperCLASS?) or SuperCLASS?) (Shallow-wide – 2.0 sq(Shallow-wide – 2.0 sqοο))

Tier 0 – Tier 0 – 180hrs e-Merlin (L-band) + JVLA-A 180hrs e-Merlin (L-band) + JVLA-A Tier 1 – Tier 1 – 360hrs e-Merlin360hrs e-Merlin++40hrs JVA-A (L-band) 40hrs JVA-A (L-band) + +

[Data Observed] [Data Observed] 380hrs e-Merlin380hrs e-Merlin+ + JVLA-A/B/C JVLA-A/B/C (C-band)(C-band) mosaic mosaic [Some test data taken][Some test data taken]

A tiered e-Merlin + JVLA + EVN Legacy proposal A tiered e-Merlin + JVLA + EVN Legacy proposal

The The e-MERe-MERlin lin GGalaxy alaxy EEvolution Surveyvolution Survey

Tier 0 – Tier 0 – Normal galaxies out to z ~ 5Normal galaxies out to z ~ 5Deep imaging around clusters to utilise amplification by lensing Deep imaging around clusters to utilise amplification by lensing

Tier 1 – Tier 1 – Very deep survey of μJy radio source populationVery deep survey of μJy radio source populationDeep imaging of the Deep imaging of the µJy radio sources in GOODS-N µJy radio sources in GOODS-N

e-MERLIN Legacy e-MERLIN Legacy programmesprogrammes

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

ee-MERLIN matches sensitivity of old (18 days) MERLIN in 24 hrs -MERLIN matches sensitivity of old (18 days) MERLIN in 24 hrs on source on source

L-bandL-band: Single pointing centre, ~20 days including 76m Lovell : Single pointing centre, ~20 days including 76m Lovell telescope.telescope.

Central 12 arcminute field Central 12 arcminute field 11 ~ ~ 500nJy/beam (500nJy/beam (in combination in combination with JVLAwith JVLA))

Outer 30 arcminute field Outer 30 arcminute field 11 ~ ~ 11µµJy/beamJy/beam

Lovell – 76mLovell – 76m

Knockin – 25mKnockin – 25m

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

ee-MERLIN will image ~580 -MERLIN will image ~580 starbursts and ~270 AGN starbursts and ~270 AGN with an angular resolution with an angular resolution of ~200 mas, complete to of ~200 mas, complete to ~3µJy ~3µJy (>10 times (>10 times

deeper than the 2005 study)deeper than the 2005 study) In the surrounding 800 In the surrounding 800 square arcmins, square arcmins, ee-MERLIN will -MERLIN will image ~2500 star-forming image ~2500 star-forming galaxies and ~1200 AGN galaxies and ~1200 AGN brighter than ~6µJy brighter than ~6µJy

Ultra-deepUltra-deep C-bandC-band mosaic + ultra-deep mosaic + ultra-deep EVN L-BandEVN L-Band

AGN activity & AGN activity & feedback feedback

580580++272700

25002500++12120000

>5000 sources in 0.2 square degree field >5000 sources in 0.2 square degree field

Population Population synthesis: synthesis: Matt JarvisMatt Jarvis

ee-MERLIN matches sensitivity of old (18 days) MERLIN in 24 hrs -MERLIN matches sensitivity of old (18 days) MERLIN in 24 hrs on source on source

L-bandL-band: Single pointing centre, ~20 days: Single pointing centre, ~20 days

Central 12 arcminute field Central 12 arcminute field 11 ~ ~ 500nJy/beam500nJy/beam

Outer 30 arcminute field Outer 30 arcminute field 11 ~ ~ 11µµJy/beamJy/beam

Original Global VLBI study confirmed AGN core-Original Global VLBI study confirmed AGN core-jetsjets

& AGN/starburst composites in high-z sub-mm & AGN/starburst composites in high-z sub-mm sources.sources.

New ultra deep EVN study to 3µJy (EG078) over New ultra deep EVN study to 3µJy (EG078) over central central

region to study feedback from faint AGN in region to study feedback from faint AGN in starburstsstarbursts

PI Mike Garrett – PhD Jack RadcliffePI Mike Garrett – PhD Jack Radcliffe

Chi et al Chi et al 20132013

Sub-mm Sub-mm AGN/Starburst AGN/Starburst

composite at composite at z=4.424z=4.424

AGN core-jet in 20.6AGN core-jet in 20.6magmag

elliptical galaxy at elliptical galaxy at z=0.681z=0.681

Muxlow et al 2005Muxlow et al 2005

Muxlow et al 2005Muxlow et al 2005

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

JVLA C-band C-array mosaic

JVLA L-Band

Test Test e-e-Merlin L-band data (1.23-1.74GHz Merlin L-band data (1.23-1.74GHz full full uvuv coverage) coverage)

~6 days elapsed, (~48 hrs on source with Lovell)+ 29 hrs JVLA A-array ~6 days elapsed, (~48 hrs on source with Lovell)+ 29 hrs JVLA A-array

(~10% of Tier 1 (~10% of Tier 1 e-e-Merlin allocation)Merlin allocation)

Only a few classical radio galaxy structures – most AGN are small core-jetsOnly a few classical radio galaxy structures – most AGN are small core-jetsAGN Wide-angled tail radio galaxy (Total 5.3mJy) AGN Wide-angled tail radio galaxy (Total 5.3mJy)

AGN Test

Image

HST ACS: I=22.9mag galaxy z=1.2653

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

JVLA C-band C-array

Test Test e-e-Merlin L-band data + 29 hrs JVLA A-array (1.23-1.74GHz BW Merlin L-band data + 29 hrs JVLA A-array (1.23-1.74GHz BW 512MHz)512MHz)

AGN Wide-angled tail radio galaxy (Total 5.3mJy) AGN Wide-angled tail radio galaxy (Total 5.3mJy)

CI 10μJy/bm Peak 139 μJy/bm

AGN Test

Image

Test Test e-e-Merlin L-band data + 29 hrs JVLA A-array Merlin L-band data + 29 hrs JVLA A-array

AGN Wide-angled tail radio galaxy (Total 5.3mJy) AGN Wide-angled tail radio galaxy (Total 5.3mJy)

HST ACS: I=22.9mag galaxy z=1.2653

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

JVLA C-band C-array

J123725+621128 e-Merlin+JVLA 0.3” beam CI 7.5μJy/bm Peak 133 μJy/bm

JVLA L-Band

e-Merlin+JVLA L-Band New Image300mas beam CI 7.5µJy/bm

CI 10μJy/bm Peak 139 μJy/bm

HST ACS: I=22.9mag galaxy z=1.2653

Old Image

AGN Test

Image

Extended steep-spectrum (Extended steep-spectrum (αα>1.62) >1.62) starburst with starburst with embedded AGN? (Sembedded AGN? (S1.4 1.4 = 393= 393μμJy). AGN variability between Jy). AGN variability between 1996 & 2013?1996 & 2013?

LL1.41.4 =8.5x10 =8.5x102323 W/Hz W/Hz Star-formation rate ~200 M Star-formation rate ~200 M๏๏/yr /yr (0.1-100M (0.1-100M๏๏ assuming Salpeter IMF)assuming Salpeter IMF)

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

JVLA L-Band JVLA L-Band

e-e-Merlin test data +JVLA L-Merlin test data +JVLA L-BandBand11σσ ~2.75µJy/bm - CI 6.2µJy/bm ~2.75µJy/bm - CI 6.2µJy/bmPeak 38µJy/bm Peak 38µJy/bm

Muxlow et al Muxlow et al 20052005

StarburstTest

Image

Old Image

New Image

HST ACS: I=19.8mag galaxy z=0.5032

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

e-e-Merlin test data +JVLA L-Merlin test data +JVLA L-BandBand11σσ ~2.75µJy/bm - CI 6.2µJy/bm ~2.75µJy/bm - CI 6.2µJy/bmPeak 38µJy/bm Peak 38µJy/bm

Muxlow et al Muxlow et al 20052005

Extended steep-spectrum (Extended steep-spectrum (αα>1.62) >1.62) starburst with embedded AGN? starburst with embedded AGN? (S(S1.4 1.4 = 393= 393μμJy). AGN variability between 1996 & 2013?Jy). AGN variability between 1996 & 2013?

LL1.41.4 =8.5x10 =8.5x102323 W/Hz W/Hz Star-formation rate ~200 M Star-formation rate ~200 M๏๏/yr (0.1-/yr (0.1-100M100M๏๏ assuming Salpeter IMF)assuming Salpeter IMF)

EG078 to look for faint radio core….EG078 to look for faint radio core….

Bright galaxy core shows BL emission Bright galaxy core shows BL emission Optical AGN activity Optical AGN activity

StarburstTest

Image

Old Image

New Image

Tier 1: New Ultra-Deep Study of GOODS-NTier 1: New Ultra-Deep Study of GOODS-N

Ultra wide-field data allows imaging to the edge of the outer field:Ultra wide-field data allows imaging to the edge of the outer field:

62mJy FR-II imaged (test data) 62mJy FR-II imaged (test data)

– – 10.4 arcminutes from field centre10.4 arcminutes from field centre

e-Merlin L-Band

JVLA L-Band

Seymour et al 2008 Haarsma et al 2000 Hopkins 2004

The co-moving Star-The co-moving Star-Formation Rate Density Formation Rate Density of the Universe from of the Universe from L-Band radio studies by L-Band radio studies by Seymour et al (2008), Seymour et al (2008), Haarsma et al (2000), & Haarsma et al (2000), & UV, HUV, Hαα, , Far-IR… Hopkins Far-IR… Hopkins (2004)(2004)

L-Band results from L-Band results from the e-MERGE the e-MERGE survey will provide survey will provide data for several data for several thousand more thousand more sourcessources

tightening the tightening the Seymour error bars Seymour error bars by a factor ~4 & by a factor ~4 & extending to z~5extending to z~5

Does it stay flat to Does it stay flat to z~5 ?z~5 ?

Star-formation History of the Universe Star-formation History of the Universe - from Starburst Luminosities - from Starburst Luminosities

Tier 0: Imaging sub-µJy galaxiesTier 0: Imaging sub-µJy galaxies

Expect ~50 amplified sources Expect ~50 amplified sources with with

intrinsic fluxes as faint as intrinsic fluxes as faint as 300nJy300nJy

Measure faint radio countsMeasure faint radio counts

May include SF galaxies withMay include SF galaxies with

SFR~200MSFR~200M๏๏/yr to z~5/yr to z~5

40µJ40µJyy

3µJy3µJy

0.3µJy0.3µJy

●● StarburstStarburst Sub-mmSub-mm

A single L-Band A single L-Band pointing on a pointing on a strong lensing strong lensing cluster A2218 cluster A2218 (z=0.18). (z=0.18).

Old MERLIN+VLA Old MERLIN+VLA imagingimaging

Tier 1 imagingTier 1 imaging

Tier 0 imagingTier 0 imaging (+Tier 1 (+Tier 1 stacking)stacking)

e-MERGE will characterise the µJy & sub-µJy radio source e-MERGE will characterise the µJy & sub-µJy radio source population population

the target population for the SKA in future high redshift SF the target population for the SKA in future high redshift SF studiesstudies