Pre-biotic Chemistry in the ISM: from Cold Cores to Galactic Center Clouds

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1 Pre-biotic Chemistry in the ISM: from Cold Cores to Galactic Center Clouds Izaskun Jimenez-Serra (STFC Ernest Rutherford Fellow) Shaoshan Zeng (QMUL), David Quenard (QMUL), Paola Caselli (MPE), Serena Viti (UCL), Anton Vasyunin (MPE), Victor Rivilla (Arcetri), Rafael Martin-Domenech (CAB), Leonardo Testi (ESO), Jesus-Martin-Pintado (CAB), Sergio Martin (ESO), Miguel Requena-Torres (JU), Denise Riquelme (MPIfR), Nuria Marcelino (ICMM), Nicolas Billot (IRAM), Charlotte Vastel (IRAP), Bertrand Lefloch (IPAG), Rafael Bachiller (OAN), Rebeca Aladro (Chalmers)

2 Pre-biotic Chemistry in the ISM: from Cold Cores to Galactic Center Clouds Izaskun Jimenez-Serra (STFC Ernest Rutherford Fellow) Shaoshan Zeng (QMUL), David Quenard (QMUL), Paola Caselli (MPE), Serena Viti (UCL), Anton Vasyunin (MPE), Victor Rivilla (Arcetri), Rafael Martin-Domenech (CAB), Leonardo Testi (ESO), Jesus-Martin-Pintado (CAB), Sergio Martin (ESO), Miguel Requena-Torres (JU), Denise Riquelme (MPIfR), Nuria Marcelino (ICMM), Nicolas Billot (IRAM), Charlotte Vastel (IRAP), Bertrand Lefloch (IPAG), Rafael Bachiller (OAN), Rebeca Aladro (Chalmers)

3 Star Formation in our Galaxy Star formation deeply embedded in molecular clouds A v >100 mag è only accessible at λ = mm/sub-mm & far-ir

4 The Formation of a Solar-type System

5 The Formation of a Solar-type System Caselli & Ceccarelli (2012) n & T different physical conditions and processes at every stage è different types of chemistry è different levels of chemical complexity

6 From the ISM to the Origin of Life Caselli & Ceccarelli (2012)

7 Molecules in Space Almost 200 molecules have been detected in space From CDMS catalog (

8 Molecules in Space Almost 200 molecules have been detected in space SgrB2(N) & SgrB2(M) Tmb (K) IRAM 30m NOEMA Rest Frequency (Mz) Belloche+2013 Observe molecular rotational transitions at mm/sub-mm λ s JCMT 8 ALMA SMA

9 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009) From CDMS catalog (

10 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009)

11 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009)

12 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009)

13 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009)

14 Complex Organic Molecules (COMs) in Space COMs are carbon-based compounds with >6 atoms (erbst & van Dishoeck 2009)

15 Pre-biotic COMs in Space Prebiotic COMs: species believed to be involved in the processes leading to the origin of life Formamide (N 2 CO) Glycolaldehyde (C 2 OCO) Amino Acetonitrile (N 2 C 2 CN)

16 Pre-biotic COMs in Space Prebiotic COMs: species believed to be involved in the processes leading to the origin of life Formamide (N 2 CO) Glycolaldehyde (C 2 OCO) Amino Acetonitrile (N 2 C 2 CN) Phosphorus Monoxide (PO)

17 First detections of COMs in the ISM Ø Star forming regions: ot Cores and ot Corinos (ollis+2000,2004; Beltran+2009; Belloche+2016; Jorgensen+2012; Lykke+2017) Ø Galactic Center GMCs (SgrB2) (Martin-Pintado+2001;Requena-Torres+2006,2008) Glycolaldehyde (C 2 OCO) T B (K) δ (J2000) Beltran+2009 α (J2000) ν (Gz) Amino Acetonitrile ( 2 NC 2 CN)

18 First detections of COMs in the ISM Ø Star forming regions: ot Cores and ot Corinos (ollis+2000,2004; Beltran+2009; Belloche+2016; Jorgensen+2012; Lykke+2017) Ø Galactic Center GMCs (SgrB2) (Martin-Pintado+2001;Requena-Torres+2006,2008) δ (J2000) Beltran+2009 COM chemistry triggered by α (J2000) T B (K) proto-stellar heating (T gas /T dust > 100 K) ν (Gz) Glycolaldehyde (C 2 OCO) Amino Acetonitrile ( 2 NC 2 CN)

19 COM formation in hot sources COMs formed mainly via: 1. ydrogenation ( addition; Charnley et al. 1997, 2001) 2. Radical-radical surface reactions (efficient at T>30 K; Garrod et al. 2008) (Burke & Brown 2010)

20 COMs ubiquitous in the ISM Ø Star forming regions: ot Cores and ot Corinos (ollis+2000,2004; Beltran+2009; Belloche+2016; Jorgensen+2012; Lykke+2017) Ø Galactic Center GMCs (SgrB2) (Martin-Pintado+2001;Requena-Torres+2006,2008) Ø Molecular Outflows (Arce+2008; Codella+2015,2017) Ø Photon-Dominated Regions (Guzman+2013; Cuadrado et al. 2017) Ø Dark Clouds Cores and Pre-stellar Cores (Marcelino+2007; Oberg+2010; Bacmann+2012; Cernicharo+2012; Vastel+2014)

21 COMs ubiquitous in the ISM Ø Star forming regions: ot Cores and ot Corinos (ollis+2000,2004; Beltran+2009; Belloche+2016; Jorgensen+2012; Lykke+2017) Ø Galactic Center GMCs (SgrB2) (Martin-Pintado+2001;Requena-Torres+2006,2008) Ø Molecular Outflows (Arce+2008; Codella+2015,2017) Ø Photon-Dominated Regions (Guzman+2013; Cuadrado et al. 2017) Ø Dark Clouds Cores and Pre-stellar Cores (Marcelino+2007; Oberg+2010; Bacmann+2012; Cernicharo+2012; Vastel+2014) Radical-radical surface formation inefficient at T<30 K

22 COM formation in cold sources (T=10 K) Radical-radical surface formation inefficient at T<30 K New mechanisms proposed: 1. Gas phase formation (Vasyunin & erbst 2013; Balucani+2015; Vasyunin+2017) 2. Non-canonical explosions (Rawlings et al. 2013) 3. Cosmic-ray induced radical diffusion (Reboussin et al. 2014) 4. Impulsive spot heating on grains (Ivlev et al. 2015) 5. Formation after atom addition/abstraction on grains (Chuang et al. 2016) Av=3 Av=10 time (years) time (years)

23 Pre-stellar cores: Precursors of Solar-type systems L1544 (Taurus) Pre-stellar cores: Cold and dense cores on the verge of gravitational collapse (no star inside yet) Keto & Caselli 2008 Caselli+2002 Δδ (arcsec) Δδ (arcsec)

24 Caselli+2002 Δδ (arcsec) L1544 as a testbed Water vapour in L1544 (Caselli+2012) Δδ (arcsec) Caselli+2012

25 Caselli+2002 Δδ (arcsec) L1544 as a testbed Water vapour in L1544 (Caselli+2012) COMs released alongside water (C 3 O, 2 CCO, COO, C 3 CO) (Vastel+2014) Δδ (arcsec) C 3 O-ring at r~4000 AU C 3 O peak (0,0 ) Bizzocchi et al Intermediate density shell interesting chemistry appears

26 IRAM 30m Detection of large COMs in L1544 C3OCO, C3OC3, C3CO, c-c32o, C2CCN, C3NC, CCNC, CCCO (0,0) Jimenez-Serra et al. (2016)

27 IRAM 30m Detection of large COMs in L1544 C3OCO, C3OC3, C3CO, c-c32o, C2CCN, C3NC, CCNC, CCCO C3O peak Jimenez-Serra et al. (2016)

28 COM abundance profile in L1544 Jimenez-Serra et al. (2016) C 3 O, C 3 CO: >6-10 x more abundant at r~4000 AU C 3 OC 3, C 3 OCO and N-bearing COMs: ( ~2-3 x more abundant at r~4000 AU

29 COM abundance profile in L1544 Jimenez-Serra et al. (2016) Important non-detections: X [Glycine] < X [N 2 CO] < (Lopez-Sepulcre+2014) X [C 3 NCO] < (Cernicharo+2016)

30 O-bearing COM chemical modelling in L AU Vasyunin et al. (2017) UV photodissociation of COMs n( 2 )<10 4 cm -3 Strong depletion onto grains n( 2 )>10 6 cm -3 Moderate Av + No severe depletion (CO) n( 2 )~10 4 cm -3

31 O-bearing COM chemical modelling in L AU Vasyunin et al. (2017) Catastrophic depletion of CO è CO snow-line in pre-stellar cores Strong depletion onto grains Moderate Av + No severe depletion (CO) UV photodissociation of COMs n( 2 )<10 4 cm -3 n( 2 )>10 6 cm -3 n( 2 )~10 4 cm -3

32 Small-scale structure of the C3O peak C3O shows inward motions (gas accretion?) Gas dynamics need to be considered Punanova+17, subm.

33 Modelling the chemistry of N-bearing COMs Glycine (N 2 C 2 COO) Methylamine N 2 C 3 Glycolaldehyde OC 2 CO ydroxylamine N 2 O Cyanamide N 2 CN Methyl Formate COOC 3 Acetamide N 2 COC 3 Aminoacetonitrile N 2 C 2 CN Acetic Acid C 3 COO Formamide N 2 CO N-methyl Formamide N-C 3 NCO Isocyanic Acid (+isomers) NCO/CNO/OCN Methyl Isocyanate C 3 NCO Requires understanding of the chemistry of the precursors of glycine and of any COM-related species.

34 Modelling the chemistry of N-bearing COMs David Quenard Methylamine N 2 C 3 Glycolaldehyde OC 2 CO ydroxylamine N 2 O Glycine (N 2 C 2 COO) Cyanamide N 2 CN Methyl Formate COOC 3 Acetamide N 2 COC 3 Aminoacetonitrile N 2 C 2 CN Acetic Acid C 3 COO Formamide N 2 CO N-methyl Formamide N-C 3 NCO Isocyanic Acid (+isomers) NCO/CNO/OCN Methyl Isocyanate C 3 NCO Requires understanding of the chemistry of the precursors of glycine and of any COM-related species.

35 Modelling the chemistry of N-bearing COMs David Quenard Methylamine N 2 C 3 Glycolaldehyde OC 2 CO ydroxylamine N 2 O Glycine (N 2 C 2 COO) Cyanamide N 2 CN Methyl Formate COOC 3 Acetamide N 2 COC 3 Aminoacetonitrile N 2 C 2 CN Acetic Acid C 3 COO Formamide N 2 CO N-methyl Formamide N-C 3 NCO Isocyanic Acid (+isomers) NCO/CNO/OCN Methyl Isocyanate C 3 NCO Mar=n- Domenech+(2017) Ligterink et al. (2017) Requires understanding of the chemistry of the precursors of glycine and of any COM-related species.

36 Modelling of N 2 CO, C 3 NCO, NCO (& isomers) UCL_CEM (Viti et al. 2004; oldship et al. 2017; Quenard et al. subm.) Gas-phase + Dust Grain chemical code (310 species; 3097 # of reactions) Recently proposed gas-phase/grain-surface reactions (including isomers): Quenard et al. subm.

37 Modelling of N 2 CO, C 3 NCO, NCO (& isomers) UCL_CEM (Viti et al. 2004; oldship et al. 2017; Quenard et al. subm.) Astronomical sources considered in the modelling: L1544 IRAS16293 B Cold Core T=10 K n( 2 )~ cm -3 Cold envelope T=20 K n( 2 )~10 6 cm -3 ot corino T=250 K n( 2 )~10 8 cm -3

38 L1544 (core center + C 3 O peak) N 2 CO is produced by a combination of gas-phase and dust-grain processes T=10 K N 2 CO formed mainly by gas phase reaction N CO -> N 2 CO + at cold T (better match obtained with E a ~25 K, slightly higher than that of Skouteris+2017) C3O peak (T=10 K) X(N 2 CO)~7x10-13 X(C 3 NCO)~6x10-12 (Jimenez-Serra+2016)

39 X(N 2 CO)~6x x10-9 X(C 3 NCO)~2x10-10 (Coutens+2016; Martin-Domenech+2017; Ligterink+2017) IRAS (cold envelope + hot corino) Cold envelope (T=20 K) gas-phase dominates hydrogenation unlikely (Noble+2015; Fedoseev+15) T=110 K X(N 2 CO)~3x10-12 (Lopez-Sepulcre+2014) T=20 K ot corino (T=250 K) Radical-radical diffusion dominates

40 X(N 2 CO)~6x x10-9 X(C 3 NCO)~2x10-10 (Coutens+2016; Martin-Domenech+2017; Ligterink+2017) IRAS (cold envelope + hot corino) Cold envelope (T=20 K) gas-phase dominates hydrogenation unlikely (Noble+2015; Fedoseev+15) X(N 2 CO)~3x10-12 T=110 K (Lopez-Sepulcre+2014) Formamide forms both in the gas-phase and/ or on grains depending on the physical conditions T=20 K ot corino (T=250 K) Radical-radical diffusion dominates

41 Search for pre-biotic species Advantages: Tgas<10 K low level of line confusion! Narrow linewidths <0.5 kms-1 little line blending L1544 Easier line identification. Not limited by sensitivity any longer Searches with ALMA and SKA!!!

42 Formamide with SKA1 TW ydrae ALMA GASS + LIME N Gz Abundance (wrt 2 ) 10-6 N 2 CO UCL_CEM TW 1 arcsec (~50 AU) SKA-MID Band 5 (Phase 1) Quenard et al., in prep Radius (AU)

43 Formamide with SKA2 TW ydrae ALMA GASS + LIME N Gz 10-6 N 2 CO 10-8 Abundance (wrt 2 ) UCL_CEM TW 40 mas (~2 AU) SKA-MID Band 5 (Phase 2) Radius (AU) Quenard et al., in prep.

44 T mb (K) Simulations of Glycine in L1544 Jimenez-Serra et al. (2014) T(K), log[n (cm -3 )] χ(mol) Derived 2 O vapour profile (Caselli+2012) Glycine abundance in ices ~0.01% wrt 2 O (Munoz-Caro+2002; Bernstein+2002). Radius (AU) Intensities > 10 mk!!! L1544 (T=10K) Brightest lines appear at ν < 85 Gz ALMA Band 2

45 Chemical complexity in the Galactic Center Shaoshan Zeng Central Molecular Zone (central 100 pc) hosts 80% of dense gas in the MW (star-forming + quiescent GMCs)

46 Chemical complexity in the Galactic Center Battersby et al. (2016) G G G Martin-Pintado et al. (2001); Requena-Torres et al. (2006,2008)

47 Requena-Torres et al. (2006,2008) Chemical complexity in the Galactic Center Battersby et al. (2016) G G G The quiescent GMCs in the Galactic Center: main reservoir of COMs in the Galaxy

48 Chemical complexity in the Galactic Center G Quiescent GMC -> no sign of star-formation activity q n( 2 )~4x10 4 cm -3 q T dust <20 K q T gas >100 K q Richest quiescent GMC in COMs (Requena-Torres et al. 2008)

49 G G mm survey 2mm survey 93 species detected 50% of them are COMs

50 O-O O C=O -C=O <8.6E E C=O 8.8E-9 6.5E-8 C 3 O 2.1E-9 <3.4E-9 O C 3 O 4.5E-7 1.1E-6 COO 2.7E-9 3.7E-9 2 CO 2 O O-bearing COMs in G COO C C COOC 3 4.5E-8 7.8E-8 3 COOC C C 3 OC 3 C 3 OC 3 2.7E-8 5.6E-8 C 3 COO <1.6E-9 <8.0E-10 CCOO O. C=C=O 2 C=C=O 7E-9 1.6E-8 2 C 2 =CO <4.5E-9 <1.8E-8 C 3 C=O 1.4E-8 3.0E-8 2 O C 3 C 2 O 3.1E-8 6.0E-8 OC 2 C 2 O 9.0E-9 2.8E-8 C C-C C-C-C 3 2 C 2 OC=O 6.8E-9 1.8E-8 2 O=C-C=O OCCO C-C 2 4 O 3.0E-9 5.6E-9 C. C C-C=O <5.7E-10 <3.6E-9 C C-C=O 9.0E E-9 2 C 2 =C-C=O 4.5E E-9 2 C 3 C 2 C=O 2.3E-9 4.4E-9 2 C 3 C 2 C 2 O <7.2E-9 <1.2E-8 Zeng et al., in prep. O-N N=C=O 9.6E-8 1.3E-7 O NCO N 2 CO 3.4E-9 6.7E-10 N 2 CO N 2 C 2 O COON 2 O-O-N C COCON 2 C 2 OCON 2 C 3 OCON 2 <1.2E-10 <4.3E-8 N=C=C=O 2 N 2 C=C=O 2 N 2 C 2 C=O 2 N 2 C 2 C 2 O <1.1E-9 <1.0E-8 C(O)C N <9.0E-10 <2.3E-9 N 2 C(O)C 3 3.6E-9 3.4E-9 N C-C=C=O 4.5E-10 <1.0E-9

51 N-O-O C C-C C 3 OCON 2 C COON 2 <8.08E-10 2 C-C-C C-C-C-C C-C-C-C-C COOC 2 N 2 N-O N N-N -N=C 3.81E-9 NC=N <3.53E-10 CO CO CNO 3.22E-10 ONC <7.71E-12 N 2 C=N 8.65E-10 O N OCN 4.87E-10 O C N N NCO -C N 6.74E-9 2 C=N 1.04E-9 C 2 N 1.37E-9 O C 2 N 2 N 2 C 2 O N 2 CO N 2 CO 9.06E-10 NCO C 3 N E-9 NCO 8.86E-8 C 3 N C C C N 2 C 2 C 2 O <2.2E-10 2 N 2 C 2 C=O N 2 C(O)C C-C N 6.64E-7 C 3 C=N C 3 C 2 N -CO-C N <9.71E C-C N 3.22E C-C N 4.65E-9 O CCN C 3 C 2 N 2 2 C=C=N <2.38E-9 C 2 C=N C 3 C=N C-C 2 4 N <2.87E-10 C 2 C=N 2 <1.17E-9 C 3 CN 2 C 3 NCO 1.4E-9 C 3 CNO <3.87E-11 C 3 OCN <1.22E C N-CO C C C O C C-C N 8.65E-10 -C C-C N 1.5E-8 -NC-C C 5.85E-11 -C C-NC 1.54E-9 C-C-C N C 2 =C-C N 1.81E-9 C 3 CC N C 3 C 2 C N 1.40E-9 C 3 C 2 CN C 3 C 2 CN C 3 C 2 C 2 N C 3 C 2 C 2 N 2 N-bearing COMs in G N C-C=C=O <4.24E-10 C C.. -C C-C-C N <4.44E-11 2 C=C=C-C N <1.06E-10 C 4 N. 2 C=C=C-C N 8.86E-10 3 C-C C-C N 5.59E-10 C 3 C 3 =N C 3 C 3 =N C 3 C 3 2 N C 3 C 3 2 N 2 C C C 3 C 2 C=N C 3 C 2 2 C=N C 3 C 2 3 C=N C 3 C 2 4 C=N Zeng et al., in prep. C 5 N -C C-C C-C N 6.13E-9 C -C 7 N 3.45E-10 -C 9 N <2.93E-11

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53 Conclusions Ø COMs are ubiquitous in the ISM. Large COMs even detected in PSCs and quiescent GC GMCs. Ø COM abundance profile predicted by chemical modelling -> Outer, intermediate-av shells in PSCs represent the main O-bearing COM reservoir. Ø Chemistry of N 2 CO, C 3 NCO, NCO in PSCs and hot corinos can be reproduced considering both gas-phase chemistry and dust grains. Ø Quiescent GC GMCs richest COM repository in the MW. Survival of COMs under extreme conditions.

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55 Modelling of N 2 CO, C 3 NCO, NCO (& isomers) L1544 -> N 2 CO gas-phase formation (N CO -> N 2 CO + ) requires a small activation barrier of 25 K (Quenard et al., subm.)

56 Chemical differentiation in L1544 Spezzano et al. (2017)

57 Where does CO depletion occur? Caselli et al. (1999) DEC Offset (arscsec) Integrated Intensity (km s -1 ) RA Offset (arscsec) RA Offset (arscsec) Low-Av shell: MAIN RESERVOIR of COMs IN PRE-STELLAR CORES

58 Modelling of N 2 CO, C 3 NCO, NCO (& isomers) UCL_CEM (Viti et al. 2004; oldship et al. 2017; Quenard et al. subm.) Gas-phase + Dust Grain chemical code (310 species; 3097 # of reactions) a) Thermal desorption (Viti et al. 2004; Collings et al. 2004) b) Non-thermal desorption (direct UV, CR-induced UV, direct CR, 2 form.) New treatment of grain surface chemistry (Quenard et al. in prep.): 1. Diffusion (asegawa et al. 1992) 2. Chemical reactive desorption (Minissale et al. 2016) 3. Reaction-diffusion competition (Garrod & Pauli 2011; Ruaud et al. 2015)