FRONTIERS:
The as ochemical jou ney om young s ella
nu se ies o exoplane s
A s udy o he 13C and 15N
ac iona ion in low-mass s a less
co es
Sigu d S. Jensen, Sil ia Spezzano, Paola Caselli,
Olli Sipilä, Elena Redaelli, Ka ha ina Gie s, Judi Fe e
Asensio
CAS-MPE, Ga ching
C edi : Bill Sax on (NRAO)
Chemical e olu ion du ing s a - and plane o ma ion
Dense co e
Plane a y sys em
P o os ella phase
P o oplane a y disk
C edi : Bill Sax on (NRAO)
Chemical e olu ion du ing s a - and plane o ma ion
Ni ogen and ca bon ac iona ion!
o HCN
Inhe i ance o ese ?
Impac o he en i onmen in ac iona ion
Spezzano e al. (2022)
Local en i onmen / Co e s uc u e Cloud en i onmen
Jensen e al. (2019)
•Ni ogen iso opic ac iona ion (14N/15N) is a powe ul ace o chemical
e olu ion. !
•F ac iona ion p ocesses depend on he physical condi ions du ing he
o ma ion o he ni ogen bea ing molecule.!
•So a , ni ogen ac iona ion is puzzling, wi h bo h inc eased and dec eased
14N/15N a ios obse ed (wi h espec o Sola Nebula alues), depending on
he molecula ca ie .!
•Se e al diffe en p ocesses a play:!
•Iso ope-selec i e pho odissocia ion!
•Nucleosyn he ic effec s!
•Chemical imbalances (endo he mic eac ions)
T acing chemical e olu ion du ing s a - and plane o ma ion
Ni ogen ac iona ion
T acing chemical e olu ion du ing s a - and plane o ma ion
Ni ogen ac iona ion o HCN
Re e ences in Jensen e al. (2024)!
T acing chemical e olu ion du ing s a - and plane o ma ion
Ni ogen ac iona ion o HCN
Main goal:
Inc easing sample size
Re e ences in Jensen e al. (2024)!
•Two me hods:!
•Indi ec double iso ope me hod: obse a ions o
H13CN and HC15N and assumed ixed 12C/13C a io
(68, Milam+2005).!
•Di ec me hod: Obse a ions o (op ically hick) HCN,
along wi h H13CN and HC15N. Spec al line modeling
o de e mine bo h 14N/15N and 12C/13C a ios.
De e mining he 14N/15N a io o HCN
Obse a ions o s a less and p e-s ella co es
C edi : Bill Sax on (NRAO)
IRAM 30m elescopeIRAM 30m
C edi :IRAM,K.Zache
FTS50 o a 50 kHz
esolu ion o esol e
HFS
Di ec me hod
P e-s ella co e TMC2
Jensen e al. (2024)!
Di ec me hod
Jensen e al. (2024)!
Di ec me hod
Di ec
Indi ec
Jensen e al. (2024)!
A lowe 12C/13C a io in young co es?
•Di ec me hod sugges a lowe alues:!
L1495 (45, Magalhães e al. 2018), !
B1-b (30, Daniel e al. 2013)!
L483 (34, Agúndez e al. 2019)!
This wo k.!
•Modeling sugges a io e ol es o e ime:!
Loison e al. 2020, Colzi e al. 2020, Sipilä e al. 2023
Sipilä e al. (2023)!
Loison e al. (2020)!
Summa y
•Using he indi ec me hod we es ima ed he HCN 14N/15N a io o
6 co es. The esul s o he indi ec me hod a e close o he PSN
alues o a ound 440.!
•Using he di ec me hod, we a e able o es ima e bo h 14N/15N
and 12C/13C a ios o i e ou o six co es. The esul s show lowe
12C/13C a ios be ween 20-40 o 4/5 co es.!
•We need o be ca e ul using he indi ec me hod. Howe e , he
di ec me hod equi es a well-de ined sou ce s uc u e.!
•The esul s show no clea e olu ion be ween he p e-s ella and
p o os ella phases. P o oplane a y disks a e gene ally lowe , bu
mos a e de i ed using he indi ec me hod. We need mo e da a!
FRONTIERS:
The as ochemical jou ney om young s ella
nu se ies o exoplane s
