ALMA and VLA imaging of intense galaxy-wide star formation at z~2: - PowerPoint PPT Presentation


 Distant Star-Forming Galaxies in the Hubble Ultra-Deep Field ALMA and VLA imaging of intense galaxy-wide star formation at z~2: bridging SMGs to the Main Sequence 11.2 billion light-years 9.0 billion light-years Wiphu Rujopakarn 
 Chulalongkorn University Durham — August 1, 2017 Team: Alexander, Biggs, Bhatnagar, Ballantyne, Cibinel, Dickinson, Dunlop , Elbaz, Geach, Hayward, Ivison, Jagannathan, Kirkpatrick , McLure, Micha ł owski, Miller, 9.4 billion light-years 10.9 billion light-years Narayanan , Nyland, Owen, Pannella, Papovich, Pope , Rau, Rieke, Robertson, Color composite: Hubble Space Telescope (visible wavelength) 
 Scott, Silverman, Swinbank , van der Werf , van Kampen, Weiner, Windhorst et al. Red overlay: Karl G. Jansky Very Large Array (radio wavelength)

Key questions • How/when did galactic spheroid and their SMBH form? • What is the true morphology of star formation in main- sequence galaxies at z ~ 2? Compact? Disk-wide? • Where exactly is the accreting SMBH in relation to the sites of star formation? • Spatially-resolved imaging of the bulk of star formation and pinpointing AGN in SFGs at z ~ 2 is key

KMOS 3D Typical, main- sequence SFGs at z ~ 2 
 — mostly rotation- dominated, disk-like systems Wisnioski+15 3

Astronomical Science Dunlop J. S., A Deep ALMA Image of the Hubble Ultra Deep Field ☉ All the actions occurred in the ‘dust era’ — Almost no rest-UV light escape from galaxies forming stars at just ≳ 0.2 the MS rate. The true faces of growing galaxies are mostly hidden Figure 5. The evolution of co-moving star formation Cosmic Star Formation Rate (M ☉ yr -1 Mpc -3 ) 800 Optical image: rate density ( ρ SFR ) as a function of redshift (upper panel) and cosmic time (lower panel). The blue 800 points and blue (double power-law) fjtted curve ��� A Typical Star-Forming Galaxy at z ~ 1.6 show the raw, unobscured UV-derived values of ρ SFR 600 600 (derived from: Cucciati et al., 2012; Parsa et al., 2016; McLure et al., 2013; and McLeod et al., 2015). The red points and curve indicate the dust-obscured 400 400 � ��� �� � � �� �� ��� �� � estimates of ρ SFR derived from the present ALMA study of the HUDF (Dunlop et al., 2016). The black points and curve show total ρ SFR ; at < 2 the data 200 200 are from Cucciati et al. (2012) and Burgarella et al. Hubble , 600 nm (2013), while at > 2 the black data points are simply 0 0 the sum of the blue (unobscured) and red (dust- Actual picture: obscured) values. ���� far-infrared luminosity density as a func- Obscured SF tion of redshift, converting the luminosity densities to visible and obscured star Unobscured SF formation rate densities respectively (see Dunlop, WR et al. 2017 Kennicutt & Evans, 2012). M yr -1 kpc -2 � � � � � �� VLA, 5 cm 1 2 ��������� � Our knowledge of the evolution of the Redshift (z) cosmic star formation rate density follow- ing the fjrst results from WFC3+HST SF clumps in optical/UV not always indicate mergers; also, optical/UV clumps contains <20% of SF and Herschel (both of which came into ��� operation in 2009) was reviewed by Behroozi et al. (2013) and Madau & Dick- inson (2014). However, the deeper census of dust-obscured star formation enabled � ��� �� � � �� �� ��� �� � by the new ALMA results allows us to better determine the relative evolution of obscured and unobscured star forma- tion at redshifts = 2–5. The implications of our new results are summarised in Figure 5. The upper panel shows the evo- ���� lution of unobscured, obscured and resulting total star formation rate density as a function of redshift, with the lower panel simply showing the equivalent information as a function of cosmic time. Now it can be seen clearly that, while the star formation density around the � � �� peak epoch at = 2–2.5 is overwhelm- ������������������� ingly dominated by dust-obscured emis- sion from massive galaxies, at redshifts targets for further ALMA pointed imaging+ Ellis, R. S. et al. 2013, ApJ, 763, L7 Fujimoto, S. et al. 2016, ApJS, 222, 1 higher than ~ 4 the dust-obscured spectroscopy extending to shorter wave- Geach, J. E. et al. 2013, MNRAS, 432, 53 component drops off rapidly, with the lengths, and for future study with the Hughes, D. H. et al. 1998, Nature, 394, 241 consequence that the star-forming Uni- James Webb Space Telescope (JWST). Kennicutt, R. C. & Evans, N. J. 2012, ARA&A, verse is primarily unobscured at earlier 50, 531 Kirkpatrick, A. et al. 2015, ApJ, 814, 9 times (i.e., within 1.5 Gyr of the Big Bang). Madau, P. & Dickinson, M. 2014, ARA&A, 52, 415 McLeod, D. J. et al. 2015, MNRAS, 450, 3032 Deeper imaging (for example, Walter et McLure, R. J. et al. 2013, MNRAS, 432, 2696 Behroozi, P. S., Wechsler, R. H. & Conroy, C. 2013, al., 2016) and wider-area surveys with Michalowski, M. J. et al. 2016, arXiv:1610.02409 ApJ, 770, 57 Narayanan, D. et al. 2015, Nature, 525, 496 ALMA have the potential to clarify this Bourne, N. et al. 2016, arXiv:1607.04283 Noeske, K. G. et al. 2007, ApJ, 660, L43 Burgarella, D. et al. 2013, A&A, 554, 70 behaviour still further, and in particular to Parsa, S. et al. 2016, MNRAS, 456, 3194 Chabrier, G. 2003, PASP, 115, 763 determine the evolution of dust-obscured Rujopakarn, W. et al. 2016, arXiv:1607.07710 Coppin, K. E. K. et al. 2006, MNRAS, 372, 1621 star formation activity as a function of Speagle, J. S. et al. 2014, ApJS, 214, 15 Cucciati, O. et al. 2012, A&A, 539, 31 Walter, F. et al. 2016, ApJ, in press, arXiv:1607.06768 redshift at fjxed galaxy stellar mass. In Daddi, E. et al. 2007, ApJ, 670, 156 Weiss, A. et al. 2009, ApJ, 707, 1201 Dunlop, J. S. et al. 2016, MNRAS, in press, addition, the sources uncovered by these arXiv:1606.00227 deep ALMA surveys are obvious attractive 52

Sub-arcsecond resolution, 
 extinction-free, sensitive tracers 
 Combining JVLA and ALMA of star formation at z ~ 2 5 ESO / NRAO

VLA HUDF Survey • Single pointing centered at the HUDF • 6 GHz, 7’ field, 0.3’’ resolution • A, B, C configs; 177 hours total • 0.32 μ Jy/beam RMS • 5 σ SFR limit: 15 M ⊙ /yr/beam at z = 2 • Deepest radio image of the sky as of 2017 Courtesy D. Medlin 1’’ ~ 8 kpc from 1 < z < 3; beam ~ 2.5 kpc 6

GOODS-S 
 ALMA ‘wedding cake’ — central region of the 
 Chandra Deep Field South surveys in HUDF and GOODS-S 
 — three nested ALMA dust continuum surveys to capture distant SFGs HUDF GOODS-S ALMA — PI: Elbaz 68 sq. arcmin, 256 GHz, 128 uJy/beam rms ALMA-JVLA — PI: Kohno 23 sq. arcmin, 271 GHz, 60 uJy/beam rms ALMA HUDF — PI: Dunlop 4.5 sq. arcmin, 220 GHz, 29 uJy/beam rms ALMA Deep Field published in Dunlop, WR+16; Hubble ACS/WFC3, Spitzer , and Elbaz Cy4 data delivered, Cy5 program approved; 
 Herschel deep survey footprint Kohno data delivered; Walter+ line scan covers the HUDF

Jansky VLA 5 cm, 0.3 μ Jy/beam rms ALMA 1.3 mm, 29 μ Jy/beam rms 16 sources in VLA, not in ALMA HUDF 11 sources in ALMA and VLA WR+16 
 Dunlop, WR+17

Why both VLA and ALMA? 1000 • 177 h VLA is more sensitive to SF at SFR limit (M ⊙ /yr/beam, 4 𝝉 ) z < 2.6; ALMA 20 h wins at z > 2.6 
 — need both to cover the peak of VLA SFR Sensitivity galaxy assembly (z ~ 1 - 3) 100 • VLA: SF + AGN 
 ALMA HUDF ALMA: dust associated to SF; 10 generally AGN-free • Map SFR, cold dust, and in some cases, pinpoint radio AGN 1 0 2 4 6 z 9

The sample of VLA and ALMA HUDF sample ALMA-selected SFGs are in the main sequence at z ~ 2 • 11 galaxies; 6 host X-ray AGN MS fit (z ~ 2) • log(M*/M ⊙ ) = 9.8 − 10.8 Daddi+07 
 • SFR = 79 − 318 M ⊙ /yr Whitaker+12 
 Whitaker+14 
 • f gas ~ 0.5 ± 0.2 
 Speagle+14 t dep ~ 0.4 ± 0.2 Gyr • Dust and gas properties 
 consistent with MS SFGs Dunlop, WR+17 10

Stellar-mass maps serves as a reference frame 
 to pinpoint sites of intense star formation bzH H-band Σ Stellar Mass HST/F160W Rest-frame optical has 
 Spatially-resolved SED 
 SF clumps in addition 
 fitting is needed to map 
 to the M* clump the M* distribution z = 2.75 Merger or 
 isolated? 1’’ Pixel-by-pixel SED fitting (Cibinel et al. 2015) using 29.5 - 30.5 mag AB ACS/WFC3 images in the HUDF; 
 Perform asymmetry-M20 analysis on these maps to classify as isolated or disturbed. Cibinel+15

Star formation and cold dust maps from VLA and ALMA UDF8 VLA Σ SFR ALMA Σ dust z = 1.55, 4’’ x 4’’ cutouts HST 1.0, 1.4, 1.6 μ m Rest-frame Optical HST 0.6 μ m Rest-frame M � yr − 1 kpc − 2 10 6 M � kpc − 2 UV 0.2 1.1 2.0 2.5 5.0 7.6 Bell 2003 indicator, assuming S ~ v -0.7 Li & Draine 2001 dust, T d = 25 K Will IRX-beta works 
 for MS galaxies at z ~ 2? WR+16