The z=0.89 molecular absorber toward PKS1830211:
molecules as cosmological probes
Sébastien Muller Onsala Space Observatory, Sweden
Cosmology for All – Lund, 2013 Feb. 4
- Chemical inventory and gas properties in distant galaxies
- No distance dilution
- Spatial resolution (continuum illumination ~ few mas)
Interests of molecular absorption studies at z>0
As cosmological probes
- CMB temperature as a function of redshift
- Test of variations of fundamental constants (, μ=mp/m
e)
- H0
- Chemical enrichment of the Universe (isotopic ratios)
Source z(abs)Background continuum
flux(Jy @3mm)
N(H2)
(cm2)
Molecules detected
Cen A 0.002 6 2 x 1020 CO, OH, NH3, CN, HCO+, HCN, N2H+, CS, H2CO, C3H2
3C293 0.045 2 x 1019 CO, HCO+, HCN
4C31.04 0.060 1 x 1019 CO, HCO+, HCN
PKS 1413+135 0.247 0.5 5 x 1020 CO, CN, HCO+, HCN, HNC
B 1504+377 0.673 0.4 5 x 1020 CO, HCO+, HCN, HNC
B 0218+357 0.685 0.5lensed
4 x 1021 CO, NH3, H20, HCO+, HCN, HNC, CS, H2S, H2CO
PKS 0132097 0.765 0.4 OH (only)
PKS 1830211 0.886 23lensed
2 x 1022 > 40 ! species (not incl. isotopic variants)
Extragalactic radiomm molecular absorbers
e.g. see review by Combes 2008
PKS1830-211 is the most notableradio molecular absorber at z>0
Of the only 5 distant radio molecular absorbers known to date(0.24 < z < 0.89)
PKS1830-211 has:
- highest redshift: z=0.89
- brightest mm continuum
- largest amount of absorbing material
- gravitational lens
- molecular absorption toward the SW and NEimages of the quasar
- time variations (continuum & molecular profile)
Unbiased ATCA-7mm spectral survey
- Frequency coverage 30 - 50 GHz with ATCA
- 28 species + 8 isotopic variants detected toward the SW LOS
- Molecular abundances similar to that of Galactic diffuse/translucent cloudsUniversality of chemistry !
- Excitation mostly coupled with the CMB photons
- Additional velocity components at -300, -225, and +170 km/s (unknown origin)
Muller et al 2011
ALMA Early Science (Cycle 0) data
APEX - Menten et al 2008
The ground-state transition of ortho-water:-> Deepest absorption of all observed lines-> Heavy saturation toward SW LOS-> Multiple velocity components toward both LOS-> Absorption spanning a large velocity range
Muller et al in prep
H2O
ALMA: Absorption along the NE LOS
- Multiple velocitycomponents
- Large velocity span
- Similarity of H2O and
HCO+ profiles
- Optically thin lines
ATCA Muller et al 2011
1 atom 2 atoms 3 atoms 4 atoms 5 atoms 6 atoms 7 atoms
H CH NH2
NH3
CH2NH CH
3OH CH
3NH
2
C OH H2O H
2CO c-C
3H
2CH
3CN CH
3CCH
CO C2H l-C
3H l-C
3H
2NH
2CHO CH
3CHO
CS HCN HNCO H2CCN
SiO HNC HOCO+ H2CCO
NS N2H+ H
2CS C
4H
SO HCO+ HC3N
SO+ HCO
HOC+
H2S
H2Cl+
HCS+
C2S
Chemical inventory toward the SW LOS
42 species+ 14 isotopic variants
See Muller et al 2011, 2013 + in prep
@ z=0.89 !
ATCA 7 mm + 3 mmRADEX + Monte Carlo Markov ChainsBest fit to the data:
TCMB
= 5.08 ± 0.10 K (68%)
Tkin
~ 80 K
n(H2) ~ 1000 - 2000 cm-3
Muller et al 2013
Multi-transition excitation analysis
TCMB
= 5.08 ± 0.10 K
-> Consistent with adiabatic expansion of the Universe:
TCMB
(z) = T0 x (1+z) … = 5.14 K @z=0.89
The TCMB
– redshift law
See Noterdaeme et al 2011
Probing the cosmological variations offundamental constants of Physics with molecules
Astronomical constraints toward highz quasars cover longer time (and space) spanthan laboratory measurements
A variation of e.g. or µ=mp/m
e would introduce a shift in transition frequency
Hence a velocity offset between two lines i,j with different freq dependence in a, µ
∆Vij / c = (Kµ
i – Kµ
j ) ∆µ/µ + (Kα
i – Kα
j ) ∆α/α
Sensitivity coefficients
- H2: |∆Kµ| ~ 0.01
- Inversion lines of NH3 wrt a rotational line: |∆Kµ| = 3.5 Flambaum & Kozlov 2007
- Various lines of CH3OH have different sensitivity: Kµ = -40 to +50 Jansen et al 2011
- CI wrt a rotational line |∆Kµ| = 1, |∆Kα| = 2
- CH @532,536 GHz wrt a rotational line: |∆Kµ| = 0.8, |∆Kα| = 1.6 de Nijs et al 2012
- OH conjugate lines have sensitivity to G=gp(µα2)1.85 e.g. Kanekar et al 2010
e.g. Constraints on ∆µ/µ using moleculesMethod Target ∆µ/µ Ref.
inv.NH3 vs (HCO+, HCN) B0218+357 z=0.68 < 1.8 x 106 Murphy et al 2008
inv.NH3 vs HC
3N PKS1830211 z=0.89 < 1.4 x 10-6 Henkel et al 2009
inv.NH3 vs (CS, H
2CO) B0218+357 z=0.68 < 3.6 x 10-7 Kanekar 2011
inv.NH3 vs (average of 22 species) PKS1830211 z=0.89 < 2.2 x 10-6 Muller et al 2011
CH3OH vs (average of 22 species) PKS1830211 z=0.89 < 1.4 x 10-6 Muller et al 2011
CH3OH PKS1830211 z=0.89 < 6.3 x 10-7 Ellingsen et al 2012
CH3OH PKS1830211 z=0.89 < 3.0 x 10-7 Bagdonaite et al 2013
Issues:
- Chemical segregation -> Observe self-reference (e.g. CH3OH)
-> Statistical constraint wrt multi references
- Excitation/opacity effects
- Time variability of the continuum -> Simultaneous observation of reference
- Change of the continuum morphology with frequency
Time delay and H0
Altern. using molecules
Wiklind & Combes (1999)
SEST monitoringHCO+ J=2-1 line
Time delay: 24 (-4 +5) days
+ Lens model (Nair et al 1993)
H0 = 69 (-11 +12)km s-1 Mpc-1 (q0=0.5)
Total continuum fluxNE + SW images
Depth of HCO+ 2-1 line (= flux of SW image)
Time delay + lens model => geometrical measurement of H0
Need to 1) Resolve the NE-SW images, separated by 1''2) Disentangle the core-jet emission of the quasar
ATCA 8.6 GHz Time delay = 26 (-5+4) days (Lovell et al 1998)
Isotopic ratios
Ratio @z=0.89 Note Earth
D/H < 7e4 Upper limit Cosmic 2.5e5
12C/13C 30 ? Difficult to measure due to opacity / fractionation effects 89
14N/15N 100 200 ~< (Uncertainty from 12C/13C) 272
16O/18O ~100 < (Uncertainty from 12C/13C) 499
18O/17O 13 ± 3 > 5.5
28Si/29Si 7 ± 0.5(preliminary)
< 22
29Si/30Si 1.9 ± 0.3(preliminary)
~ 1.5
32S/34S 10.5 ± 0.5 < 22.5
35Cl/37Cl ~3 ~ 3.1
- PKS1830-211 is a unique target for molecular absorption studies
-> Basic gas properties and interstellar chemistryin the disk of a z=0.89 galaxy
- Molecules as cosmological probes:
-> Evolution of the CMB temperature with z-> Variations of fundamental constants-> H0-> Isotopic ratios and nucleosynthesis constraints
- Unfortunately, only a handful of known z>0 mm-radio absorbersNeed to find more !
Summary
Top Related