Chemical di e si y o p es ella co es and p o os a s
in he O ion B molecula cloud
Helena Mazu ek
2s Yea PhD s uden
Obse a oi e de Pa is
LUX labo a o y
Ma ch 10, 2025
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 1 / 20
P esen a ion ou line
1P ojec o e iew
2Sou ce selec ion
3Gene al s a is ics o ace s
4PCA analysis
5Abundances and deple ion e ec
6Summa y and ou look
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 2 / 20
P esen a ion ou line
1P ojec o e iew
2Sou ce selec ion
3Gene al s a is ics o ace s
4PCA analysis
5Abundances and deple ion e ec
6Summa y and ou look
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 3 / 20
O ion Molecula Cloud Complex
View on he cons ella ion o O ion
Image c edi : Rogelio Be nal And eo
Top: Op ical iew on O ion B
Image c edi : Alan Smallbone
Bo om: Molecula emission o
12CO,C18 O,N2H+
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 4 / 20
O ion Molecula Cloud Complex
View on he cons ella ion o O ion
Image c edi : Rogelio Be nal And eo
Top: Op ical iew on O ion B
Image c edi : Alan Smallbone
Bo om: Molecula emission o
12CO,C18 O,N2H+
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 4 / 20
O ion Molecula Cloud Complex
View on he cons ella ion o O ion
Image c edi : Rogelio Be nal And eo
Top: Op ical iew on O ion B
Image c edi : Alan Smallbone
Bo om: Molecula emission o
12CO,C18 O,N2H+
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 4 / 20
ORION-B p ojec
Millime e-wa e obse a ional p og amme
mapping a la ge ac ion o he O ion B gian
molecula cloud
•40 GHz spec al co e age and a ield o
iew o 5 deg ees squa ed a ∼30”
esolu ion
•25 molecula ace s om di e en
amilies o molecula species (ex. CO,
ni ogen bea ing N2H+, o ganic CH3OH,
H2CO)
•Selec ed ields co e ed also by (2-1)
obse a ions o 12CO,13CO and C18O
Full ield o iew o ORION-B obse a ions in
di e en CO iso olopologues
(12CO,
13 CO,C18O)
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 5 / 20
ORION-B p ojec : Chemical di e si y o p es ella co es and p o os a s
Millime e-wa e obse a ional p og amme
mapping a la ge ac ion o he O ion B gian
molecula cloud
•40 GHz spec al co e age and a ield o
iew o 5 deg ees squa ed a ∼30”
esolu ion
•25 molecula ace s om di e en
amilies o molecula species (ex. CO,
ni ogen bea ing N2H+, o ganic CH3OH,
H2CO)
•Selec ed ields co e ed also by (2-1)
obse a ions o 12CO,13CO and C18O
Full ield o iew o ORION-B obse a ions in
di e en CO iso olopologues
(12CO,
13 CO,C18O)
Cha ac e isa ion o p es ella co es and p o os a s using molecula ace s and
addi ional en i onmen al pa ame e s (NH2,n,Tdus ,G0) o unde s and he
unde lying eason o hei di e si y
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 5 / 20
P esen a ion ou line
1P ojec o e iew
2Sou ce selec ion
3Gene al s a is ics o ace s
4PCA analysis
5Abundances and deple ion e ec
6Summa y and ou look
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 6 / 20
P esen a ion ou line
1P ojec o e iew
2Sou ce selec ion
3Gene al s a is ics o ace s
4PCA analysis
5Abundances and deple ion e ec
6Summa y and ou look
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 11 / 20
PCA analysis
To combine he in o ma ion om he many ace s a ailable and de i e a common
axis o a ia ion be ween he sou ces, we pe o med P incipal Componen
Analysis on ou da a
As inpu we used he measu ed
luxes ans o med wi h
a×a csinh(x/a), in which a is
scaled by he median noise in he
da ase .
This ans o ma ion ensu es ha
he alues a e mo e e enly
dis ibu ed, so ha he highes
alues o ”missing” alues do no
d i e he a iance The i s 3 componen s explain o e 85%
o he a ia ion in he da a
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 12 / 20
Con ibu ion o each line o he i s 3 PCs
0.50
0.25
0.00
0.25
0.50
PC1 70.3 %
0.50
0.25
0.00
0.25
0.50
PC2 8.35 %
12CO(1 0)
13CO(1 0)
C18O(1 0)
C17O(1 0)
HCO
HCO+(1 0)
H2CO
HNCO
C3H2
CH3OH(2 1)
H13CO+(1 0)
DCO+(1 0)
HCN(1 0)
H13CN(1 0)
HNC(1 0)
HN13C(1 0)
N2H+(1 0)
12CN(1 0)
DNC(1 0)
12CS(2 1)
CCH(1 0)
32SO(2 1)
SiO(2 1)
HCS+(1 0)
CCS
0.50
0.25
0.00
0.25
0.50
PC3 6.94 %
PC con ibu ion pe sou ce
NH2,Tdus
Co e ace s
UV ace s
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 13 / 20
How “ obus ” a e he selec ed sou ces?
0.50
0.25
0.00
0.25
0.50
PC1 70.3 %
0.50
0.25
0.00
0.25
0.50
PC2 8.35 %
12CO(1 0)
13CO(1 0)
C18O(1 0)
C17O(1 0)
HCO
HCO+(1 0)
H2CO
HNCO
C3H2
CH3OH(2 1)
H13CO+(1 0)
DCO+(1 0)
HCN(1 0)
H13CN(1 0)
HNC(1 0)
HN13C(1 0)
N2H+(1 0)
12CN(1 0)
DNC(1 0)
12CS(2 1)
CCH(1 0)
32SO(2 1)
SiO(2 1)
HCS+(1 0)
CCS
0.50
0.25
0.00
0.25
0.50
PC3 6.94 %
Robus sample
0.40
0.15
0.10
0.35
0.60
PC1 60.14 %
0.40
0.15
0.10
0.35
0.60
PC2 13.26 %
12CO(1 0)
13CO(1 0)
C18O(1 0)
C17O(1 0)
HCO
HCO+(1 0)
H2CO
HNCO
C3H2
CH3OH(2 1)
H13CO+(1 0)
DCO+(1 0)
HCN(1 0)
H13CN(1 0)
HNC(1 0)
HN13C(1 0)
N2H+(1 0)
12CN(1 0)
DNC(1 0)
12CS(2 1)
CCH(1 0)
32SO(2 1)
SiO(2 1)
HCS+(1 0)
CCS
0.40
0.15
0.10
0.35
0.60
PC3 8.98 %
S a less co es
The p e-selec ion o co es on con inuum da a cap u es he mos di e se and likely
s a - o ming co es, which is con i med by he PCA applied o he molecula da a
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 14 / 20
How “ obus ” a e he selec ed sou ces?
0.50
0.25
0.00
0.25
0.50
PC1 70.3 %
0.50
0.25
0.00
0.25
0.50
PC2 8.35 %
12CO(1 0)
13CO(1 0)
C18O(1 0)
C17O(1 0)
HCO
HCO+(1 0)
H2CO
HNCO
C3H2
CH3OH(2 1)
H13CO+(1 0)
DCO+(1 0)
HCN(1 0)
H13CN(1 0)
HNC(1 0)
HN13C(1 0)
N2H+(1 0)
12CN(1 0)
DNC(1 0)
12CS(2 1)
CCH(1 0)
32SO(2 1)
SiO(2 1)
HCS+(1 0)
CCS
0.50
0.25
0.00
0.25
0.50
PC3 6.94 %
Robus sample
0.40
0.15
0.10
0.35
0.60
PC1 60.14 %
0.40
0.15
0.10
0.35
0.60
PC2 13.26 %
12CO(1 0)
13CO(1 0)
C18O(1 0)
C17O(1 0)
HCO
HCO+(1 0)
H2CO
HNCO
C3H2
CH3OH(2 1)
H13CO+(1 0)
DCO+(1 0)
HCN(1 0)
H13CN(1 0)
HNC(1 0)
HN13C(1 0)
N2H+(1 0)
12CN(1 0)
DNC(1 0)
12CS(2 1)
CCH(1 0)
32SO(2 1)
SiO(2 1)
HCS+(1 0)
CCS
0.40
0.15
0.10
0.35
0.60
PC3 8.98 %
S a less co es
The p e-selec ion o co es on con inuum da a cap u es he mos di e se and likely
s a - o ming co es, which is con i med by he PCA applied o he molecula da a
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 14 / 20
P esen a ion ou line
1P ojec o e iew
2Sou ce selec ion
3Gene al s a is ics o ace s
4PCA analysis
5Abundances and deple ion e ec
6Summa y and ou look
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 15 / 20
Exci a ion empe a u es and abundances: obse a ions
Fou ields co e ed by (2-1) obse a ions. Co es and
p o os a s a e anno a ed wi h black and yellow
c osses, espec i ely.
Complemen a y obse a ions
o C18O(2−1) p o ide
addi ional in o ma ion
needed o de i e exci a ion
empe a u e
In an op ically hin LTE
scena io, his is enough o
es ima e he column
densi ies
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 16 / 20
Exci a ion empe a u es and abundances
Despi e co es being exposed o
di e en en i onmen s, hey appea o
be deple ed in all s udied egions.
Howe e , his equi es u he
e i ica ion, as in some cases his
e ec is p obably ela ed o
pho odissocia ion Deple ion uppe and lowe limi s om Fuen e+12
( ed dashed line). Median ela i e abundance w .
NH2(g een dashed line)
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 17 / 20
Exci a ion empe a u es and abundances
Despi e co es being exposed o
di e en en i onmen s, hey appea o
be deple ed in all s udied egions.
Howe e , his equi es u he
e i ica ion, as in some cases his
e ec is p obably ela ed o
pho odissocia ion Deple ion uppe and lowe limi s om Fuen e+12
( ed dashed line). Median ela i e abundance w .
NH2(g een dashed line)
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 17 / 20
Mul i-laye adia i e ans e model*
In o de o ge he bes es ima es o column densi ies, olume densi ies and
empe a u es o all co es in ou sample, we use a mul ilaye adia i e ans e
model (“sandwich model‘’, Segal+24) ha decomposes he emission p o ile in o
dense s uc u es ( ilamen s/co e) and he su ounding gas laye s
The cu en con igu a ion includes species wi h low (CO iso opologues) and high
(HCO+) dipole momen s o ensu e sensi i i y o a wide ange o physical
condi ions.
Once he physical condi ions a e de e mined, he emission lines o o he species
such as N2H+, DCO+e c. will be i ed wi h a sandwich o 1D model
Helena Mazu ek (LUX, Pa is) Ma ch 10, 2025 18 / 20
