Herschel 3.5m 2009-2013 IRAM Plateau de Bure 6  12 x 15m H2O and other molecules in Herschel high-z galaxies. A new diagnosis of their dense cores Alain Omont (IAP, CNRS & UPMC) On behalf of Chentao Yang + H-ATLAS and IRAM Teams

OUTLINE Introduction: Herschel high-z lensed submillimeter galaxies (SMGs) H2O in local ULIRGs from Herschel spectroscopy H2O ubiquitous emission in high-z (lensed) SMGs Excitation of high rotational levels  diagnosis of dense warm cores/clumps with strong IR Detection of H2O satellite lines: H2O+  chemistry of H2O formation Complementary multi-line CO observations Work in progress / Prospects: - High-angular-resolution multiline mapping - Probing outer galaxy layers with absorption lines - High-J HCN, HCO+ & HNC in dense, star-forming gas. - Bright future with ALMA

Herschel high-z lensed SMGs Mm/submm is extremely powerful for detecting high-z sources Herschel SPIRE surveys (250-500µm) have observed > 1000 deg2 They have detected >5 105 high-z SMGs Half are luminous ULIRGs at z>1 (SFR >~ 300 Mo/yr, LFIR ~ 3x1012-1013 Lo) Several 100’s are strongly lensed SMGs. Increased sensitivity by >~10 Lenses are easily identified among strongest submm sources versus local IRAS sources and blazars Lens deflectors are mostly ellipticals at z ~ 0.2-1 Various mm/submm high-resolution maps with SMA, IRAM/PdBI, ALMA and lens models High sensitivity used for line surveys: CO, CH+, H2O …

~10 high-resolution PdBI maps: continuum + CO (or H2O) SDP.81 ~1mm NC.143 PdBI+SMA 2mm Comprehensive survey of ~30 submm lensed galaxies by 880µm SMA maps and lens models by Bussmann et al. 2013 NB.78

Continuum Source plane: cont.+CO(5-4) CO velocity structure Revolutionary ALMA image of SDP81 in Science Verification ALMA Parnership 2015, Dye et al. 2015 Continuum Source plane: cont.+CO(5-4) CO velocity structure

H2O in local ULIRGs from Herschel spectroscopy

E.g. from Yang et al. 2013 (Herschel archive) H2O in low-z ULIRGs E.g. from Yang et al. 2013 (Herschel archive) H2O lines have been found very strong, mostly in emission, by Herschel (SPIRE-FTS, etc.) in 40 local (LIRGs/)ULIRGs, in 7 H2O lines with Eup  600K with intensity ~0.3-0.5 next CO lines

H2O in low-z ULIRGs e.g. from Yang et al. 2013 (Herschel archive) H2O lines have been found very strong, mostly in emission, by Herschel (SPIRE-FTS, etc.) in 40 local (LIRGs/)ULIRGs, in 7 H2O lines with Eup  600K and various line ratios (excitation) with intensity ~0.3-0.5 next CO lines LH2O roughly proportional to LIR  Excitation by IR Reflects the complex structure of the galaxies (e.g. Lijie Liu + in prep.): - mostly warm dense core more or less excited by IR - (plus cold extended region, + hot core + ouflows + etc.)

H2O at high redshift in Herschel lenses

H2O at high redshift in Herschel lenses Similar situation to low-z ULIRGs was expected in high-z ULIRGs (and HyLIRGs) up to 10 times more IR luminous without local equivalents Therefore H2O lines should be easily detectable in strong lenses - Main goal: detailed comparison of high-z SMGs with local ULIRGs - First high-z H2O detections in Herschel lenses (Omont+2011,2013; Combes+2012) concomitant with confirmed H2O detections in historical lensed QSOs  16 detections in H-ATLAS lenses at PdBI Omont+ 2011, 2013, Yang+ 2016  H2O seems strong in all Herschel lenses

H2O in H-ATLAS lensed sources Step 1: Detection Low-lying line: 211-202 rest 752GHz Eu=137K or 202-211 rest 989GHz Eu=103K 7 detections reported in Omont et al. 2013 9 new detections in Yang+ 2016 (A&A submitted) H2O is detected in all 16 observed H-ATLAS lenses 1.57 < z < 4.24

H2O in H-ATLAS lensed sources Step 1: Detection Omont et al. 2013 Comparison with CO PdBI CO: Cox, Ivison et al. in prep. Striking similarities of line profiles  Same region of emission  No strong differential lensing Comparable H2O and low-J CO intensities (but different l) Similar H2O and adjacent high-J CO lines (H2O/CO ~ 30-50%)

Additional detections 9/9 (16/16 in total) H2O in H-ATLAS lenses Step 1: Additional detections 9/9 (16/16 in total) Yang et al. 2016 H2O is strong in all high-z ULIRGs  detectable in all lenses with PdBI  strongest molecular lines besides CO

Good correlation with LIR Good correlation of LH2O with LIR, almost linear

H2O in H-ATLAS lensed sources Step 2: H2O excitation Excitation of high rotational levels  diagnosis of dense warm cores/clumps with strong IR radiation

Observation of a higher excitation H2O line: J=3 Eup = 300K Yang et al. in prep. 6 observed sources, 5 strong detections Again quasi-linear correlation of LH2O with LIR

Comparison of H2O excitation with local ULIRGs Yang et al. 2016. vs Yang et al. 2013 Variable but very comparable excitation of J=3 line with local ULIRGs

Diagnosis of galactic warm, dense cores/clumps H2O excitation Diagnosis of galactic warm, dense cores/clumps Detailed modeling by Gonzalez-Alfonso et al. (2014) Line ratios trace (in a complex way) conditions in emitting galactic dense cores/clumps : - Infrared :dust temperature - Infrared optical thickness - H2O column density and abundance - (Gas temperature TK and density n)

H2O excitation modeling Models of Gonzalez-Alfonso+ 2014 Two lines J=2 + J=3 provide only loose constains on Twarm & NH2O Adding J=4 line would much Improve t100 is expected ~1-3(10?) from: -scaling from local ULIRGs -or extension of FIR emission (~R~0.5-1kpc) and SFR  Mdensegas -should be confirmed by CO + continuum high-resolution mapping Twarm~45-75K depending on source Typical H2O abundance ~10-6 Twarm Twarm +/-1s contours

H2O Excitation 2. Additional constraint on H2O excitation from observation of line 422-411 (Eup/k = 450K) Marginal detection of two sources  relatively low excitation?

H2O+ as indicator of H2O chemistry/formation In gas-phase, H2O can be produced through two routes: Neutral-neutral reactions, usually related to shock, create H2O O + H2  OH + H; OH + H2  H2O + H at high temperature At lower temperature, the ion-neutral reaction in Cosmic Ray Dominated Regions (CRDRs) and X-ray Dominated Regions (XDRs) generate H2O from O, H+, H3+ and H2, with intermediates such as O+, OH+, H2O+ and H3O+, and H3O+ + e  H2O + H. Therefore, H2O+ lines are important for distinguishing between shock- or ion chemistry origin for H2O in the early universe

Detection of H2O+ in high-z Submillimeter Galaxies Strong emission of two H2O+ lines observable close to a key H2O line Seen in local galaxies Easily detectablewith NOEMA Yang et al. 2016 Strong abundance of H2O+ is key for H2O chemistry  Cosmic ray ion chemistry H2O J=2 H2O+

Complementary multi-line CO observations Complete study of CO achieved with IRAM/30m/EMIR in 6 H2O high-z galaxies Yang+ in prep (plus other by van der Werf+) SLED NOEMA proposal for higher-J study

Work in progress / Prospects: - High-angular-resolution multiline mapping - Probing outer galaxy layers with absorption lines - High-J HCN, HCO+ & HNC in dense, star-forming gas - Bright future with ALMA

High-angular-resolution multiline mapping PdBI/NOEMA 2mm Complex structures are expected for high-z SMGs, similar to, but possibly different from local ULIRGs High angular resolution (+ lens modeling) mandatory to disentangle from lensed images Confirmed by ALMA image of SDP.81 Even NOEMA may provide key information CO maps of ~10 H-ATLAS lenses (Oteo+ in prep.) SDP.81 ALMA NOEMA maps of NC.143 Yang, Omont et al. in prep. Continuum 1.2mm, 2mm 2 H2O lines, CO(10-9), H2O+ Work in progress Evidence for strong differences in various images SMA 0.88mm

Probing outer galaxy layers with absorption lines Work in progress / Prospects Probing outer galaxy layers with absorption lines Absorption by cold extended regions of the galaxy in lines connected to the ground state of H2O, H2O+ , OH, CH+, etc. Dynamics: outflows, etc. Marginal detection of H2O, H2O+ Spectacular detection of CH+ (+ very broad emission) H2O H2O+ H2O+ CH+ H2O+ Falgarone et al. submitted to Nature Yang et al. in prep.

High-J HCN, HCO+ & HNC in dense, star-forming gas HCN(1-0) best tracer of dense star-forming gas (Gao et al.) For high-z HCN(1-0) observable at VLA HCN higher-J plus HCO+, HNC, etc.) observable at mm l: ALMA, NOEMA ALMA Lupu+ HCN(3-2) PdBI Yang+ HCN(5-4), HCO+(5-4), etc. VLA Gao, Yang + HCN(1-0)

Need for ALMA deeper H2O studies in high-z SMGs ALMA allows much deeper studies: H2O in unlensed SMGs, and comprehensive studies in lensed SMGs: excitation, structure, outflows, isotopologues, (+masers) etc. The strong magnification of Herschel numerous lenses allows efficient surveys of much weaker molecular lines (H2O+, OH+, CH+, HF, HCN, HCO+, 13CO, CH3OH, etc.)  high-z astrochemistry with NOEMA  ALMA ALMA is crucial for high-resolution mapping to provide exquisite details about lens images and modeling and actual spatial structure of the sources and H2O excitation ALMA is also mandatory for fine deep studies of line profiles, outflows, inflows, extended turbulence (see e.g. CH+ results in SDP17b by Falgarone et al.) And also for isotopologues, minor species, etc.