STUDIES SCUBA-2 Ultra Deep Imaging EAO Survey ang ( , ASIAA ) W - PowerPoint PPT Presentation

STUDIES 
 SCUBA-2 Ultra Deep Imaging EAO Survey ang ( 王 為豪 , ASIAA ) W ei - Hao W on behalf of the STUDIES Team

Outline • Motivation • Survey description • Results from the first year - 450 μ m counts - Counterpart properties - case study: a z = 3.7 passive galaxy

Motivation Frequency ν [GHz] Redshifted Arp 220 SED 10 6 10 5 10 4 10 3 10 2 10 1 10 -6 10 -6 10 3 10 2 10 -7 10 -7 10 1 z=0.5 Flux (mJy) 10 0 z=1 W m -2 sr -1 W m -2 sr -1 CMB 10 -8 10 -8 z=2 960 10 -1 z=4 z=6 10 -2 z=10 10 -9 10 -9 COB CIB 10 -3 23 24 10 -4 10 -10 10 -10 10 -4 10 -3 10 -2 10 -1 10 0 10 1 10 2 10 3 -1 -1 0 0 10 1 10 1 10 2 10 2 10 3 10 3 10 4 10 4 10 5 10 5 10 10 10 10 Wavelength (mm) Wavelength λ [ μ m] Wavelength λ [ m] Dole et al. (2006) • Half of the activities in the cosmic history is hidden by dust. • 450 μ m observations are sensitive to dust emission at intermediate redshifts (z ~ 1-3)

Herschel 250 μ m, 350 μ m, 500 μ m Ks, IRAC Ch1+2, IRAC ch3+4

SCUBA-2 Ultra Deep Imaging EAO Survey (STUDIES) • An EAO JCMT Large Program • To reach SCUBA-2 confusion limit at 450 μ m (~10 × deeper than Herschel at 350/500 μ m). • 650 hr of observing time with Band-1 weather: 
 - STUDIES-COSMOS (330 hr, approved in 2015) 
 - STUDIES-SXDS (aka. UDS, 320 hr, approved in 2017) 
 - both in the CANDELS regions • one Daisy pointing in each field 
 (D = 3’ ultradeep core + D = 15’ outer region) • σ 450 μ m ≲ 0.6 mJy in the core, < 3 mJy in the entire map • execution period: 2015–2020 • about 130 team members

STUDIES: to detect typical dusty galaxies 850 μ m confusion limit STUDIES optical samples 850 μ m Herschel Limits (extinction corrected) samples STUDIES Barger et al. (2014) STUDIES will detect the typical members in the dusty galaxy population. • STUDIES will probe into the SFR of optically selected galaxies. •

STUDIES-COSMOS 
 as of Feb 2017 (40% complete) 98 sources at > 4 σ central rms ~ 0.9 mJy > 200 expected at full depth

SCUBA2 vs. Herschel SCUBA-2 450 μ m Herschel 500 μ m

450 μ m Counts 
 constrained with 4 σ sources and fluctuation analyses L IR ~ 1.5 × 10 11 L ⨀ , SFR ~ 25 M ⨀ /yr (z = 1.5) 10 6 10 4 dN/dS (deg -2 mJy -1 ) 10 2 4 σ sources fluctuation analyses 10 0 Schechter Fit Power-Law Fit 1 10 S 450 (mJy) Wang et al. (submitted, arXiv:1707.00990)

450 μ m Counts 
 compared with Herschel SPIRE counts 10 6 10 10 4 -1 ) 10 mJy -1 7x deeper -2 mJy dN/dS (deg -2 dN/dS (deg This Work This Wor 10 2 10 This Work, Schechter Fit This Work, Schechter Fit This Work, Power-Law Fi This Work, Power-Law Fit Oliver (2010) Herschel 500 um Oliver (2010) Herschel 350 um Clements (2010) Herschel 500 um 10 0 Clements (2010) Herschel 350 um 10 Valiante (2016) Herschel 500 um Valiante (2016) Herschel 350 um 1 10 10 S 450 450 (mJy) (mJy) Wang et al. (submitted, arXiv:1707.00990)

450 μ m Counts 
 compared with Herschel SPIRE counts 10 6 10 1.0 1.0 Transmission Transmission 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 10 4 -1 ) 10 mJy -1 0.0 0.0 -2 mJy 300 400 300 400 500 500 600 600 λ ( (um) m) dN/dS (deg -2 dN/dS (deg This Wor This Work 10 2 10 This Work, Schechter Fit This Work, Schechter Fit This Work, Power-Law Fi This Work, Power-Law Fit Glenn (2010) Herschel 500 um Glenn (2010) Herschel 350 um Oliver (2010) Herschel 500 um Oliver (2010) Herschel 350 um Clements (2010) Herschel 500 um 10 0 Clements (2010) Herschel 350 um 10 Bethermin (2012a) Herschel 500 um Bethermin (2012a) Herschel 350 um Valiante (2016) Herschel 500 um Valiante (2016) Herschel 350 um 1 10 10 S 450 450 (mJy) (mJy) Wang et al. (submitted, arXiv:1707.00990)

450 μ m Counts 
 compared with Herschel SPIRE counts 10 6 10 1.0 1.0 Transmission Transmission 0.8 0.8 0.6 0.6 • Herschel 500 μ m counts: 
 0.4 0.4 0.2 0.2 10 4 -1 ) - 1.4 × too high in flux 
 10 mJy -1 0.0 0.0 -2 mJy 300 400 300 400 500 500 600 600 or 
 λ ( (um) m) - 2.5 × too high in density dN/dS (deg -2 dN/dS (deg This Work This Wor 10 2 10 This Work, Schechter Fit This Work, Schechter Fit • Why? 
 This Work, Power-Law Fi This Work, Power-Law Fit Glenn (2010) Herschel 500 um Glenn (2010) Herschel 350 um - sources are clustered 
 Oliver (2010) Herschel 500 um Oliver (2010) Herschel 350 um - poor resolution (30 ″ ) 
 Clements (2010) Herschel 500 um 10 0 Clements (2010) Herschel 350 um 10 Bethermin (2012a) Herschel 500 um (Bethermin et al. 2007) Bethermin (2012a) Herschel 350 um Valiante (2016) Herschel 500 um Valiante (2016) Herschel 350 um 1 10 10 S 450 450 (mJy) (mJy) Wang et al. (submitted, arXiv:1707.00990)

Resolved 450 μ m Background Integrated Surface Brightness (Jy deg -2 ) Planck 100 100 COBE EBL Fraction (%) This Work 10 Geach (2013) 10 Casey (2013) Chen (2013b) Hsu (2016) Zavala (2017) Bethermin (2012b) 450 µ m model Lacey (2016) 450 µ m model 1 1 10 S 450 (mJy) Wang et al. (submitted, arXiv:1707.00990)

Counterpart Properties 
 (3GHz + 24 μ m identification) ◇ PACS sources (Symeonidis 2013, z<1.5) ◇ local galaxies 450 μ m detection limit (3.5 mJy, z=1) X.W. Shu et al. (in prep.)

a case study

A High-z Quiescent Galaxy • Glazebrook et al. (2017, Nature) • ZF-COSMOS-20115: 
 a massive post-starburst quiescent galaxy at z=3.717. • Quiescent because 
 1. strong Balmer absorption 
 2. no Herschel detection 11 M ⊙ • M ★ = 1.7 × 10 • requires a rapid formation Glazebrook et al. (2017) between z = 6 to 5.

Quiescent or Starburst? • STUDIES detects it at 450 μ m (3 σ ) and 850 μ m (10 σ ). ALMA also detects it at 870 μ m (7 σ ). • SFR obscured ~ 100 M ⊙ /yr. • M ★ ,unobscured ~ 0.8 × 10 11 M ⊙ • No longer requires a rapid formation history at very high z. Simpson et al. (2017)

Summary • STUDIES will observe two fields with extremely high sensitivity at 450 μ m, from 2015 to 2020. • Just 40% of the data in the COSMOS field (20% of whole STUDIES) can produce a large sample and highly accurate counts. • Herschel SPIRE counts are biased because of source clustering and low resolution. • non-detection in Herschel SPIRE bands ≠ quiescent. • More SCUBA-2 data are coming. More studies and followup observations are underway/planed.

Questions/Open Issues • Nature of the offset between SCUBA2 and Herschel counts: 
 clustering? 
 flux calibration?