Chemistry during Star and Planet Formation--Chemical diversity and its origin--

1/22

Nami Sakai (RIKEN)

2 Atoms (42 Species)H2, CO, AlF, AlCl, C2, CH, CH+, CN, CO+, CP, SiC, HCl, KCl, NH, NO, NS, NaCl, OH, PN, SO, SO+, SiN, SiO, SiS, CS, HF, HD, FeO (?),O2, CF+, SiH (?), PO, AlO, OH+, CN–, SH+, SH, HCl+, TiO, ArH+, NO+ (?), N2 , NS+

3 Atoms (40 Species)C3, C2H, C2O, C2S, CH2, HCN, HCO, HCO+, HCS+, HOC+, H2O, H2S, HNC, HNO, MgCN, MgNC, N2H+, N2O, NaCN, OCS, SO2, c-SiC2, CO2, NH2, H3

+, SiCN, AlNC, SiNC, HCP, CCP, AlOH, H2O+, H2Cl+, KCN, FeCN, HO2, TiO2, C2N, Si2C, HS2, HCS, HSC, HNO 4 Atoms (27 Species)c-C3H, l-C3H, C3N, C3O, C3S, C2H2, NH3, HCCN, HCNH+, HNCO, HNCS, HOCO+, H2CO, H2CN, H2CS, H3O+, c-SiC3, CH3, C3N–, PH3, HCNO, HOCN, HSCN, H2O2, C3H+, HMgNC, HCCO5 Atoms (23 Species)C5, C4H, C4Si, l-C3H2, c-C3H2, H2CCN, CH4, HC3N, HC2NC, HCOOH, H2CNH, H2C2O, H2NCN, HNC3 , SiH4, H2COH+, C4H–, HC(O)CN,HNCNH, CH3O, NH4

+, H2NCO+ (?), NCCNH+, CH3Cl6 Atoms (17 Species)C5H, l-H2C4, C2H4, CH3CN, CH3NC, CH3OH, CH3SH, HC3NH+, HC2CHO, NH2CHO, C5N, l-HC4H, l-HC4N, c-H2C3O, H2CCNH (?), C5N–, HNCHCN, SiH3CN, C5S(?)7 Atoms (10 Species)C6H, CH2CHCN, CH3C2H, HC5N, CH3CHO, CH3NH2, c-C2H4O, H2CCHOH, C6H–, CH3NCO, HC5O8 Atoms (11 Species)CH3C3N, HC(O)OCH3, CH3COOH, C7H, C6H2, CH2OHCHO, l-HC6H, CH2CHCHO (?), CH2CCHCN, H2NCH2CN, CH3CHNH, CH3SiH39 Atoms (10 Species)CH3C4H, CH3CH2CN, (CH3)2O, CH3CH2OH, HC7N, C8H, CH3C(O)NH2, C8H–, C3H6, CH3CH2SH (?), CH3NHCHO(?), HC7O10 Atoms (5 Species)CH3C5N, (CH3)2CO, (CH2OH)2, CH3CH2CHO, CH3CHCH2O, CH3OCH2OH11 Atoms (4 Species)HC9N, CH3C6H, C2H5OCHO, CH3OC(O)CH312 Atoms (4 Species)c-C6H6, n-C3H7CN, i-C3H7CN, C2H5OCH3 (?)>12 Atoms (3 Species)c-C6H5CN, C60, C70, C60

+

Interstellar Molecules (~200 Species)

Mostly discovered by radio-wave observations(Gray: detected only from evolved stars)

(The Cologne Database for Molecular Spectroscopy (CDMS): at 2018 May)

3/22

Outflow

~105 yr ~107 yr

Encelope

Protostellar DiskProtostar

Protostar

Plotoplanetary DiskPlanet

Core Size：~10,000 au Envelope Size:~1,000 au Disk Size:~100 au

Star

Prestellar Phase Star Formation Planetary-systemFormation

Main Sequence

Chemical Evolution

UV

Diffuse Cloud

<103 cm-3

>106 cm-3

Dense Cores~105 cm-3

105-106 yr

Molecular Cloud~104 cm-3

(cf; Size of the Solar system~100 au)

Carbon-chain molecules(CCS, C2H, etc.)

N-bearing Species(HN2+, NH3, etc.)

C → CO CO depletiononto dust grain

Gain-mantle Evaporation

Deuterated Species(H2D+, DCN, N2D+, etc.)

Chemical Evolution along Star Formation

Detections of “Complex” Organic Molecules (COMs)

HCOOCH3, CH3OCH3, C2H5CN, etc.Hot Corino Chemistry (Cazaux et al. 2003, A&A, 593, L51)

(Bottinelli et al. 2004, ApJ, 617, L69)

HCOOCH3 distributionaround IRAS16293-2422 (PdBI)

< a few 100 AU(cf; Size of the Solar system~100 AU)

Detections of COMs in NGC1333IRAS4A,NGC1333IRAS4B,

& NGC1333IRAS2A.Similar evolutionally stage

(e.g. Sakai et al. 2006, PASJ, 58, L15)

Photo: IRAM 30 m (Spain)4/22

(e.g. Sakai et al. 2008, ApJ, 672, 372; Sakai et al. 2010, ApJ, 722, 1633)

Inte

nsi

ty[K

]

HCOOCH3

0

0.05

0.1

0.15

0

0.05

0.1

0.15

Inte

nsi

ty[K

] H2CCCC

C2H, c-C3H, l-C3H, c-C3H2, l-C3H2,C4H, C4H-, C4H2, C5H, C6H, C6H2,C6H-, HC3N, HC5N, HC7N, HC9N, C2O, C3O, etc.

Warm Carbon-Chain Chemistry (WCCC)

Evaporation of CH4 from grain mantles (> 25 K)CH4 + C+ C2H3

+ + HC2H3

+ + e C2H + H + H - - - -

Discovery of WCCC in L1527

Frequency[GHz]

Frequency[GHz]

Photo: NRO 45 m (Japan)5/22

/ 39

19" grid ( ~ 2700 AU)

★ Central Concentration around the Protostar

C4H (N = 9 - 8)

C4H2, c-C3H2 :similar distributions

(Ohashi et al. 1997)W

N

Another core

∫TmbdV : HighestΔV ~ 0.6 km/s

ΔV ~ 0.3 km/s

ΔV ~ 0.3 km/s

@NRO 45 m

Existence in the infallingenvelope (~ 3,000 AU)

6/22

Slide in 2007 (NRO 45m)

C+D configurationGray: 3.5 mm continuum

1400 AU

Enhancement of Carbon-Chain Molecules in the 20-30 K region

CCH and C4H are also enhanced

(Sakai et al. 2010, ApJ, 722, 1633)

7/22

Slide in 2010 (PdBI+30m)

Primary beam correction has not been done

Unsaturated Species(Carbon-Chain Molecules, etc.)

Warm Carbon-Chain Chemistry(WCCC)

l-C4H2

HCOOCH3

(Sakai et al. 2007a; 2007b)

CH3OH(7-6, k=0 A)

L1527

Hot Corino ChemistrySaturated-

”Complex” Organic Molecules (COMs)

IRAS16293-2422

NGC1333IRAS4B

l-C4H2

(Sakai et al. 2006; 2009)

HCOOCH3

NGC1333 IRAS4A

(Bottinelli et al. 2004; Taquet et al. 2015)

Chemical Diversity of Infalling Envelopes(~500 au scale)

8/22

(PdBI)

HCOOCH3

c-C3H2(NOEMA)(PdBI)

9/22

Outflow

~105 yr ~107 yr

Encelope

Protostellar DiskProtostar

Protostar

Plotoplanetary DiskPlanet

Core Size：~10,000 au Envelope Size:~1,000 au Disk Size:~100 au

Star

Prestellar Phase Star Formation Planetary-systemFormation

Main Sequence

Chemical Evolution

UV

Diffuse Cloud

<103 cm-3

>106 cm-3

??

Chemical Variationin Planetary system?

Unsaturated Species (Carbon-Chains) are Rich

Saturated Organics are Rich

Dense Cores~105 cm-3

105-106 yr

Molecular Cloud~104 cm-3

(cf; Size of the Solar system~100 au)

Carbon-chain molecules(CCS, C2H, etc.)

N-bearing Species(HN2+, NH3, etc.)

C → CO CO depletiononto dust grain

Gain-mantle Evaporation

Deuterated Species(H2D+, DCN, N2D+, etc.)

Chemical Evolution along Star Formation2) Chemical differentiation of star-forming cores and it’s origin

(Ohashi et al. 2014, ApJ, 796, 131)

“Disk Edge” is found by ChemistryL1527Class 0TaurusEdge-onWCCCInfant Disk

(Sakai et al. 2014, Nature, 507, 78)10/22

(Sakai et al. 2014, Nature, 507, 78)

First Identification of the “Centrifugal Barrier”

@Centrifugal barrier(CB)All the kinetic energy is used for rot. motion

Angular momentum &energy conservation

( )

2

22

LmrVr

GMmVVm

rot

infallrot

=

=+

ryV

rxVV infallrotobserved +=

−=

= 22 , 1

rotinfallrot Vr

GMVrm

LV

xy★

rCB = 100±20 AU, M(star+disk) = 0.18±0.02 Mʘ

Parameter: M, L/m

11/22

・First identification of centrifugal barrier (CB)(Drastic chemical change at rCB=100 au)

・CB is the interface between envelope & disk(e.g. Oya+2016, Oya+2017a, Sakai+2017a)

Power of Chemistry!

BA

(Jorgensen et al. 2012, ApJ, 757, L4)

Inverse P Cygni Profile

(Pineda et al. 2012, A&A, 544, L7)

Line Broadening due to Rotation

BA

BA

Hot Corino:IRAS16293-2422A/B

Rotating InfallingOCS: colorModel: contour

M = 0.75 M⦿, rCB = 50 AU, i = 30º

(Rout(OCS) = 180 AU)

12/22 (Oya et al. 2016, ApJ, 824, 88)

Envelope Model

All Ring Ring Envelope

Envelope

Disk

Disk

Envelope

Centrifugal Barrier

SOH2CO

・ OCS (19-18)Infalling-rotating envelope(Rout(OCS) = 180 AU)

・ CH3OH (110,11-101,10; A++)Rotating around CB(Rout(OCS) = 80 AU)

・ HCOOCH3 (199,19-198,11; E)Rotating around CB(Rout(OCS) = 55 AU)

・ H2CS (70,7-60,6)Infalling-rotating envelope(Rout(OCS) = 150 AU)+ High velocity component

Hot Corino: IRAS16293-2422A

Envelope CB Disk

Red 70-110 110-140 70-90

Blue 70-110 100-130 70-120 (K)

Tk : derived from H2CS (k=0,2) linesn (H2) = 107-109 cm-3

N (H2CS) = 1013-1015 cm-2

13/22

1) Finding out disk edges

Chemical Diversity of Disk-Forming Regions

Hot Corinos(e.g. IRAS16293-2422,

NGC1333IRAS4A）

WCCC Sources(e.g. L1527, TMC-1A)

Chemical diversity still remains in disk forming regions

Hybrid Sources(e.g. L483, B335)

15/22

L1527 IRAS 15398

IRAS 16293A/B TMC-1A L483 B335 HH212 NGC1333IRAS4C

Evolutional Stage

Class 0/I Class 0/I Class 0binary Class I Class 0 Class 0 Class I Class 0

Chemical Composition

WCCC WCCC Hot Corino WCCC WCCC+ HC(Hybrid)

HC+WCCC(Hybrid)

HC? WCCC?

i (edge-on: 90º) 85º 70º ~ 60º/ ~5º ~ 70º ~ 40º ~90º? 96° 75°-85°

M* [M⦿] 0.18 0.007? 0.75 / 0.4 0.25 0.3 >0.13 0.25 0.2

rCB [au] 100 40? 50 / 40 50 50 <10 44 ~50? (<140)

Specific Angular Momentum: j [10-4 km/s･pc]

8.7 < 1.6 13 / 8.5 7.2 7.9 --small-- 7 6.3? (<10.5)

Identification of Centrifugal Barrier in Various Sources

Assumption: At the centrifugal barrier (rCB),all the kinetic energy is used for rot. motion M (star+inner-disk) and j (=L/m) can be determined

𝑉𝑉𝑟𝑟𝑟𝑟𝑟𝑟𝑚𝑚𝑚𝑚𝑚𝑚 =2𝐺𝐺𝐺𝐺𝑗𝑗

𝑟𝑟𝐶𝐶𝐶𝐶 =𝑗𝑗2

2𝐺𝐺𝐺𝐺cf; 𝑟𝑟𝐶𝐶𝐶𝐶(𝐹𝐹𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔=𝐹𝐹𝑐𝑐𝑐𝑐𝑐𝑐𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑔𝑐𝑐𝑔𝑔𝑔𝑔𝑐𝑐) = 𝑗𝑗2

𝐺𝐺𝐺𝐺= 2 𝑟𝑟𝐶𝐶𝐶𝐶

Sakai+2014a

Oya+2014(Yen+2017)

(Okoda+2018)

A: Oya+2016B: Oya+2018

Sakai+2016

Oya+2017a Yen+2015Imai+2016

Zhang+2018poster P37

Lee,C-F+2017Podio+2015

8 sources: typically ~50 au, no clear trend Importance of “environmental effect”. Chemistry does not only depends on evolutionally stages, but also on history/environment

1) Finding out disk edges

14/22

PdBI: <3,000 auALMA Cycle 0-1NOEMA <300 au

ALMA Cycle 2-6: <30 au(relatively simple species)

What can we observe with ALMA/NOEMA?

Chemical evolutionalong IRE->CB->Disk(COMs:2-3 mm lines)

NOEMA fits to this!16/22

NOEMA LP SOLISSeeds Of Life In Space

?

SCIENTIFIC RATIONAL: Interstellar Complex Organic Molecules (iCOMs) could be the seeds of the organics in cometary and meteoritic material and, perhaps, of life.

QUESTIONS: 1- What iCOMs are present and when during the formation of a Solar-type system?2- How are iCOMs synthesized in the Solar-type star forming regions?

?

Ceccarelli, Caselli et al. 2018, ApJ: SOLIS first results

16/22

18/22

SOLIS (result/summary)←SOLIS by NOEMA

↓ ASAI by IRAM30m

(Codella, Ceccarelli, Caselli et al. 2017, A&A Let)

Origin of COMs &chemical diversitycan be studied by NOEMA

19/22

Perseus Chemical Survey

Orange: Dust, Green Contour: CO (Hatchell et al. 2005, A&A, 440, 141; 2007, A&A, 468, 1009)

10 pc

20 pc(cf: 1000 AU = 0.005 pc)

(SOLIS)

(SOLIS)

20/22

Chemical Variation in Perseus

(Higuchi et al. 2018, ApJS, 236, 52)

PErseus ALMA CHemical survey (PEACH) is going on.(Toward the same set of sources with 0.3”-0.5” resolution (~100 au). Now in analysis)

IRAM30m/B6 + NRO45m/B3-- 1,000 scale variation --

Hot Corino

WCCCHybrid

Nar

row

dV

com

ponent

21/22

CO

CO

CO CO

CO

COH

H

H

H

H

CH3OHH2CO

CH3OH

depleted as CO

Long starless phase (~106 yr, Starting time of the collapse: Late after the UV shielding of parent cloud)

Origin of the Chemical Diversity

CH4C

C

Saturated COMs (HCOOCH3, etc.)

Hot Corino

grain hydrogenation

COCH3OH

C C

C

C

CO

H

CH

HH HCH4

CH4CH4depleted as C

Short starless phase (~105 yr, Starting time of the collapse: Early after the UV shielding of parent cloud)

C

Unsaturated COMs (Carbon-Chains)

WCCCH2CO

grain hydrogenation

(Sakai & Yamamoto 2013, Chem. Rev., 113, 8981)22/22

/ 25

1) Chemical survey of protostellar sources with limited frequency settings.--Wide frequency coverage of NOEMA

(Other axis of diversity? e.g. S-bearing, Deuterated, N-bearing,,,,,) --100-1,000 au scale resolution is required (0.7”-7” in Taurus)

(+IRAM30m High dynamic range:100-10,000 au)--Northern regions

2) Studying COMs formation in detail --Band 3-6 are rich in lines of COMs (NOEMA!)

(In B3-6, dust continuum opacity is not serious)

3) Isotopologues and rare species--Ground transition of deuterated species

(only available in 70 GHz)

4) Line survey (Talk by Y.Watanabe) --Excitation conditions, Total abundances--Whole view of chemical compositons

Astrochemical Studies on Protostallar Sourceswith NOEMA

23/22(Ernst Haeckel)