1. (Oxford Univ. & RAL-Space, STFC)
Science with ALMA Band 11
Dimitra Rigopoulou
(Oxford Univ. & RAL-Space, STFC)
Oxford, March 19 & 20th 2013

2. ALMA Band 11 : Why a THz Band
Originally ALMA to reach up to 950 GHz
But results from ISO, APEX, Herschel & SOFIA highlight the tremendous scientific potential of observing in the THz bands
Yes, above 30% transmission
Is it feasible?
Is it scientifically important?

3. Band 11: Sensitivities & Resolution
Based on work carried out by
S. Graves and J. Richer

4. redshift
High J CO transitions, H2 rotational transitions and fine structure lines

5. Band 11 Science Drivers
Very high redshift Universe: probe pristine gas in protogalaxies through detection of the pure rotational H2 lines 28 and 17 μm lines
Devriendt & Slyz, using GALACTICA
H2 is the most abundant molecule in the Universe
Its whereabouts:
found in regions where shielding from UV
photons (responsible for its dissociation) is sufficiently large Av >=0.5-1mag
Key role:
H2 formation on grains initiates chemistry of ISM
Major contributor to the cooling of astrophysical media

6. Band 11 Science Drivers
External Galaxies : Probe the properties of intermediate redshift 0.3<z<1 Universe
m (1.899 THz) in the redshift range
205 m (1.950 THz) in the redshift range ~0.8
63 m (4.758 z~0.3
Magnelli et al. (2011))

7. Band 11 Science Drivers
ELAIS-S1
z=0.27
Bootes1
z=0.35
FLS01
z=0.46
A survey of [CII], [NII] and [OI] in intermediate redshift ULIRGs
Arp220
Rangwala et al. 2011

8. Deduce HF/H2, calculate N(HF)
Band 11 Science Drivers
Interstellar Medium of the Milky Way
Probe PDRs via spatially resolved studies of [NII] and high-J CO
High/low Excitation Lines of Fundamental Molecules
HCN, HNC, HCO+
Higher J transitions of CO : e.g. CO(10-9), CO(11-10), CO(12-11)
Hydrogen GHz – tracer of H2, potential for detecting small H2 clouds
Sonnentrucker, Neufeld et al AA, 521
Deduce HF/H2, calculate N(HF)
Infer N(H2)

9. Band 11 Science Drivers Search for o-D2H+ In 16293E Upper limit for
High Mass Star Formation : SFR in galaxies traced via massive stars.
Also responsible for the buildup of chemical elements, origins of planets and Life
Para-D2H+
Ortho-D2H+
high-J transitions of CO HCN, HNC and HCO+
Low mass star Formation: fundamental rotational transitions of NH+: N2H+, NH3
Para-NH3 (2-1) multiplet and GHz, chemistry of N
H2D+ : ortho GHz BUT para 1370 GHz
dominant form of H2D+, probe mid-plane of protostellar disks
Search for o-D2H+
In 16293E
Upper limit for
o=-D2H+
Vastel et al, from the CHESS program

10. Band 11 Science Drivers
Continuum imaging

11. Band 11 Science Drivers Studies of the continuum
at z 3-5
(essesntial for constraining AGN)

12. Band 11 Science Drivers: Synergies & complementarities B11
1400 11
From ALMA-NRAO
B11
from E. Bergin

16. Para-D2H+
Ortho-D2H+

17. Band 11 Science Drivers: Spectral Lines Unique Lines:
fundamental rotational transitions of NH+: N2H+, NH3
Para-NH3 (2-1) multiplet and GHz, chemistry of N
H2D+ : ortho GHz BUT para 1370 GHz
dominant form of H2D+, probe mid-plane of protostellar disks
High Excitation Lines of Fundamental Molecules
HCN, HNC, HCO+
Higher J transitions of CO : e.g. CO(10-9), CO(11-10), CO(12-11) etc

18. Band 11 Science Drivers: Spectral Lines Unique Lines:
fundamental rotational transitions of NH+: N2H+, NH3
Para-NH3 (2-1) multiplet and GHz, chemistry of N
H2D+ : ortho GHz BUT para 1370 GHz
dominant form of H2D+, probe mid-plane of protostellar disks
High Excitation Lines of Fundamental Molecules
HCN, HNC, HCO+
Higher J transitions of CO : e.g. CO(10-9), CO(11-10), CO(12-11) etc

19. Band 11 Science Drivers: Spectral Lines Unique Lines:
fundamental rotational transitions of NH+: N2H+, NH3
Para-NH3 (2-1) multiplet and GHz, chemistry of N
H2D+ : ortho GHz BUT para 1370 GHz
dominant form of H2D+, probe mid-plane of protostellar disks
High Excitation Lines of Fundamental Molecules
HCN, HNC, HCO+
Higher J transitions of CO : e.g. CO(10-9), CO(11-10), CO(12-11) etc

20. Band 11 Science Drivers: Spectral Lines Unique Lines:
fundamental rotational transitions of NH+: N2H+, NH3
Para-NH3 (2-1) multiplet and GHz, chemistry of N
H2D+ : ortho GHz BUT para 1370 GHz
dominant form of H2D+, probe mid-plane of protostellar disks
D2H+
High Excitation Lines of Fundamental Molecules
HCN, HNC, HCO+
Higher J transitions of CO : e.g. CO(10-9), CO(11-10), CO(12-11) etc