PoS(PRA2009)020 Jy) and µ http://pos.sissa.it/ Lockman Hole using the elatively bright ( 250 osity, but only if the starburst . Two of them are detected thus ctroscopy, although they appear ntribute significantly to the radio this is with high-resolution VLBI r an alternative, dust-unobscured, deed been detected in a significant cal of star forming regions leaving integral part of the evolution of these laxy evolution - PRA2009 ts that are believed to be the precursors overy of black holes at the centres of all ord Hill, Edinburgh, EH9 3HJ, UK reet, Cambridge, MA 02138, USA ße 2, D-85748 Garching, Germany e Commons Attribution-NonCommercial-ShareAlike Licence. ∗ [email protected] [email protected] [email protected] Speaker. Submillimetre (SMGs) are high-redshift starburs to modern-day giant elliptical galaxies. AGN appear tomassive, be star-forming an galaxies; this is implied by the disc nearby, massive galaxies and tracers of AGN activity have in only the compact AGN cores. We have observed three SMGs in the fraction of SMGs e.g. vianot deep X-ray to observations be and bolometrically NIR spe route dominant. to quantifying Radio the observations contributioncontribution offe of can be AGN removed. to The the mostwhich SMG effective way filters lumin of out doing the low-brightness extended emission typi European VLBI Network at a wavelength of 18 cm. All three are r from MERLIN imaging were known to containindicating compact that structure AGN are common in radio-detected SMGsluminosity. and co ∗ Copyright owned by the author(s) under the terms of the Creativ c

Rob Ivison UK Astronomy Technology Centre, Royal Observatory, Blackf E-mail: E-mail: Josh Younger Harvard-Smithsonian Center for Astrophysics, 60 Garden St Andy Biggs European Southern Observatory, Karl-Schwarzschild-Stra E-mail: Detection of Submillimetre Galaxies in theHole Lockman using the European VLBI Network June 02 - 05 2009 Groningen, the Netherlands Panoramic Radio Astronomy: Wide-field 1-2 GHz research on ga PoS(PRA2009)020 re on -rich z will be as- HI column Andy Biggs z le to observe ave measured ovide an ideal luding the 100- hort integration pointing centre, tead we opted to : high- high- cluding calibration cycled between the . Thus, SMGs are mergers of gas-rich Gs, including X-ray ered by a mixture of oles (SMBHs) in the nd violent relaxation ecorded over a band- es in excess of several 14 25-m dishes of the BHs. s in a bright sub-sample cast the co-evolution of able of directly imaging lated with the properties ubmm surveys. Our sam- (Fig. 1). st and feedback-regulated Jy/beam. The naturally-weighted logy [8], have focused on largely µ 2 Jy) with three fainter ones to be observed in June 2009. µ Jy and for which MERLIN imaging indicates the presence of compact structu µ 250 50 > > These models of evolution predict that hyperluminous starbursts at Observations took place in June 2008 using 7 stations of the Western EVN inc Due to the very small primary beam of the WSRT phased array, it was impossib Over the past twenty years it has become clear that supermassive black h To date, most observational searches for actively growing SMBHs in SM Of the three SMGs that we primarily targeted, two were detected (Fig. 1). We h The Lockman Hole is a region of the Northern sky with a remarkably low galactic 4 GHz . 4 GHz . 1 1 S m dish at Effelsberg,WSRT the operating 76-m as Lovell a telescope phasedwidth at array. of Jodrell 64 Data Bank MHz at per andscans) a polarisation resulting the during wavelength in two of final image epochs 18 sensitivities each cm of of approximately were 10 12 r h duration (in spiral galaxies collide, triggering a gasSMBH inflow growth that fuels which a leads nuclear to starbur transform a the remnant bright into quasar, a after massive red which elliptical gas galaxy. exhaustion a nuclei of galaxies are common [6]of and the that stars their masses in are theirSMBHs strongly host corre and galaxies galaxies [4]. in Recent the theoretical context models of [3] a have cosmic cycle driven by major mergers scales of 250 mas [2]. Using the( EVN, we have to date observed three SMG synthesised beam had a FWHM of 30 mas. EVN Detections of SMGs in the Lockman Hole 1. Introduction sociated with periods of activelaboratory SMBH for growth. testing Submillimetre these galaxiesgalaxies models. (SMGs) and pr These are extreme the objectsprime likely candidates are progenitors for powered the of by transition today’s objectsstar formation massive that and theory elliptical active predicts black galaxies should hole be growth. pow the entire 6-arcmin Effelsberg primarypoint beam all with telescopes a apart single from the pointingthree WSRT position. SMGs. at a Ins This single maximised position sensitivity whilsttimes on the and our WSRT narrow primary channels targets gives whilst useful the sensitivity across use the of entire s field 3. Results density that has been studied overple the of entire SMGs spectrum, consists including of several those s withS VLA radio detections [5] within 6 arcmin of the detections [1], spectroscopy [7] andindirect far-infrared indicators. morpho Very high-resolution radio imaging,any by ultra-compact, contrast, luminous is cores cap that can only be produced by active SM 2. Sample and Observing Strategy their flux densities and sizes and from these determine brightness temperatur PoS(PRA2009)020 f the minosity note that Andy Biggs n made by ities which sive SMBHs ignificantly to erefore, while ed spectroscop- tric contribution of current theory, rce of the detected ther). These values K) compact radio emis- igh-sensitivity VLBI 5 10 × ( onnection between extreme b the growth of SMBHs and the T n R. J., Keel W. C., 2004, ApJ, 617, 64 n A. W., Brandt W. N., Ivison R. J., 2005, se E., 2007, ApJ, 669, 45 604 100% and 40% in each case. Combined with ≈ 3 Jy) EVN/VLA (%) µ 11 100 2.3 15 40 7.5 ( ± ± 4 GHz . 1 S Measured parameters of the two detected SMGs. Table 1: Source LOCKSMG1 315 LOCKSMG2 104 K (Table 1) corrected for primary beam attenuation and redshift (measur 5 ApJ, 632, 736 The extremely high resolution also allows us to separate the relative contributio These first VLBI detections of SMGs suggest that the AGN may contribute s [1] Alexander D. M., Bauer F. E., Chapman S. C., Smail I., Blai [5] Ivison R. J. et al.,[6] 2002, MNRAS, 337, Kormendy J., 1 Richstone D., 1995, ARA&A,[7] 33, 581 Swinbank A. M., Smail I.,[8] Chapman S. C., Younger J. Blain D., A. et W., Iviso al., 2008, ApJ, 688, 59 [2] Biggs A. D., Ivison R.[3] J., 2008, MNRAS, Di 385, Matteo 893 T., Springel V., Hernquist L., 2005, Nat., 433, [4] Hopkins P. F., Hernquist L., Cox T. J., Robertson B., Krau ically in one case and assumedare to high have the enough average that value for weradio the flux. can SMGs rule in out the o anything other than an AGN as the sou times 10 the bolometric luminosity in someby and selecting not radio-detected at SMGs all atsion, in the we others. epoch are of However, biased peak itthese quasar towards is detections activity those are important with SMGs interesting to as with directstarbursts a observational and evidence significant the for AGN a build-up component. c ofof AGN massive Th in SMBHs, the they broader sayarrays population little should of allow about SMGs. the the typical Future AGN bolome unbiased fraction surveys in with SMGs h to beReferences established. EVN Detections of SMGs in the Lockman Hole SMBH in these systems.suggest Our masses two in targets the have range SMBHsare 100 already with million in very to place high 1 at radio billionand the luminos provides suns. direct peak observational That of evidence these for the extremely astellar starburst causal mas component is link of in between massive galaxies. line with the expectations 4. Concluding remarks the known scaling of this quantity with SMBH mass this yields a lower limit for the mass o star formation to theof total the radio AGN. luminosity We of find our that targets, the thus AGN isolating contributes the intrinsic lu PoS(PRA2009)020 -150 -100 Andy Biggs -50 0 . MilliARC SEC σ 50 rms noise in the images is 100 that have been identified as σ 150 0 50

150 100 -50

-100 -150 MilliARC SEC MilliARC 3, 3, 4, 5, 6, 10, 20 ta. The 1- − -150 he 100-m Effelsberg telescope at the ob- by the EVN are marked with squares. The -100 weighted CLEAN maps of LOCKSMG2 (top) -50 0 4 MilliARC SEC 50 100 150 and contours are plotted at 0 50

100 -50 150 2

-100 -150 MilliARC SEC MilliARC Top-left: VLA 1.4-GHz map of the Lockman Hole. Radio sources Jy/beam, the beam size is 30 mas µ 10 Figure 1: EVN Detections of SMGs in the Lockman Hole submillimetre emitters and which have or are being targeted dashed circles indicate the 6-arcmin (FWHM) primary beam ofand t LOCKSMG3 (bottom), the two detections from the June 08 da served and to-be observed epochs. Bottom-left: Naturally-