ALMA Science Perspective

Al Wootten, ALMA/NA Project Scientist JAO Jan2010 1

The mm/Submm Spectrum:Focus of ALMA

Millimeter/submillimeter photons are the most abundant photons in the cosmic background, and in the spectrum of the Milky Way and most spiral galaxies. Most important component is the 3K Cosmic Microwave

Background (CMB) After the CMB, the strongest component is the CIB/THz

component, which carries most of the remaining radiative energy in the Universe, and 40% of that in for instance the Milky Way Galaxy.

ALMA range--wavelengths from 1cm to ~0.3 mm, covers both components to the extent the atmosphere of the Earth allows.

CIB is a focus of THz astronomy

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Eleven Years of Data

PWV < 200 μm for ~10% of timeCan be better in winter

APEX July 2008Data courtesy S. Radford

Chajnantor: An Excellent Site for THz Astronomy

APEX

• APEX is a slightly modified copy of the ALMA prototype built by Vertex.

• It has operated on the ALMA site since 2005.

• The surface is ~17 μm and has remained stable.

• Observations have been published which were made in the 1.4 THz atmospheric window.Sooo...• ALMA has an excellent and proven site for THz astronomy• ALMA has two prototype antennas; a copy of one is doing THz astronomy

• Bids now being considered for operation• ALMA has four different Production antennas—how do they compare?• What are ALMA’s science goals and how do they drive development?

ALMA Science Requirements

Project Sci IPT ensures ALMA meets three “level I” science goals: Spectral line CO/C+ in z=3 MWG <

24hrs resolve ProtoPlanetaryDisks at 150 pc

– gas/dust/fields Precise 0.1” imaging above 0.1% peak

High Fidelity Imaging. Routine sub-mJy Continuum / mK Spectral Sensitivity. Wideband Frequency Coverage. Wide Field Imaging Mosaicing. Submillimeter Receiver System (..& site..). Full Polarization Capability. System Flexibility (hardware/software).

Technical Specifications >54-68 12-m antennas, 12 7-m antennas, at 5000 m altitude site. Surface accuracy ±25 m, 0.6” reference pointing in 9m/s wind, 2”

absolute pointing all-sky. First two antennas meet these; accurate to <±16 m most conditions

Array configurations between 150m to ~15 -18km. 10 bands in 31-950 GHz + 183 GHz WVR. 84-116 GHz “3” 125-169 GHz “4” 163-211 GHz “5” 6 rx only, dual polzn 211-275 GHz “6” 275-373 GHz “7” 385-500 GHz “8” 602-720 GHz “9” 787-950 GHz “10” initially partially populated 8 GHz BW, dual polarization. Flux sensitivity 0.2 mJy in 1 min at 345 GHz (median cond.). Interferometry, mosaicing & total-power observing. Correlator: 4096 channels/IF (multi-IF), full Stokes. Data rate: 6MB/s average; peak 60 MB/s. All data archived (raw + images), pipeline processing.

ALMA Bands and Transparency

‘B11’

B10B9B8B7B6

B5

B4

B3

B2

B1

0.5mm PWV ν<950 GHz 0.2mm PWV ν>950 GHz

Specifications Breed Transformational Performance

• With these specifications, ALMA improves • Existing sensitivity, by about two orders of magnitude

• Best accessible site on Earth• Highest performance receivers available• Enormous collecting area (1.6 acres, or >6600 m2)

• Resolution, by nearly two orders of magnitude• Not only is the site high and dry but it is big! 18km

baselines or longer may be accommodated.• Wavelength Coverage, by a factor of two or more

• Take advantage of the site by covering all atmospheric windows with >50% transmission above 30 GHz

• Bandwidth, by a factor of a few• Correlator processes 16 GHz or 8 GHz times two

polarizations• Scientific discovery parameter space is greatly expanded!

First Light!

Highest Level Science GoalsBilateral Agreement Annex B:“ALMA has three level-1 science requirements: The ability to detect spectral line emission from CO or C+ in a normal

galaxy like the Milky Way at a redshift of z = 3, in less than 24 hours of observation.

The ability to image the gas kinematics in a solar-mass protostellar/ protoplanetary disk at a distance of 150 pc (roughly, the distance of the star-forming clouds in Ophiuchus or Corona Australis), enabling one to study the physical, chemical, and magnetic field structure of the disk and to detect the tidal gaps created by planets undergoing formation.

The ability to provide precise images at an angular resolution of 0.1". Here the term precise image means accurately representing the sky brightness at all points where the brightness is greater than 0.1% of the peak image brightness. This requirement applies to all sources visible to ALMA that transit at an elevation greater than 20 degrees. These requirements drive the technical specifications of ALMA. “

A detailed discussion of them may be found in the 2004 ESA publication Dusty and Molecular Universe on ALMA and Herschel.

Science Goal I: Detect CO or C+ in MWG

• At z=2 this can be done for both lines

• At z=3 this becomes difficult for the CO line

• But notice the ‘tall pole’ atomic lines in the THz region, including C+

C+

CO J=3-2

Combes

Super M82 from ISO, Beelen and Cox

As galaxies get redshifted into the ALMA bands, dimming due to distance is offset by the brighter part of the spectrum being redshifted in. Hence, galaxies remain at relatively similar brightness out to high distances.

Inverse K-correction, or magic of the submillimeter

10 11

CO rotational transitions (‘ladders’)

Weiss et al. astro-ph/0508037

Line ratios of CO rotational transitions depend on density and temperature.In Milky Way type galaxies: low-order transitions are brighter → low densities.In dense cores of starburst galaxies, higher-order transitions are brighter.At high z, higher excitation occurs, partly owing to higher CMB.

Science Goal I: Detect CO or C+ in MWG

Viable; depends onexact redshift and transparency window lineup.

For MW galaxy, detection takes a few hours.

Note that other lines on the plot, from luminous galaxies in the local Universe, may be detected, some at very high z.

ALMA allows us to see the redshifted ‘tall pole’ THz lines to very high z.

Maiolino and Testi

Hubble Deep Field Rich in Nearby Galaxies, Poor in Distant Galaxies

Nearby galaxies in HDF

Source: K. Lanzetta, SUNY-SB

Distant galaxies in HDF

Submm Sources at High and Low z

Simulation based on: (1) blank-field bright-end number counts (Wang, Cowie, Barger 2004)(2) lensing cluster faint-end number counts (Cowie, Barger, Kneib 2002)(3) redshift distribution of the submm EBL (Wang, Cowie, Barger 2004)

Wang 2008

J1148+52: A Paradigm Distant Monster Galaxy

An early (z=6.42; 0.8Gyr) massive and extended region of tremendous star formation

~1000 Msun/yr/kpc2 Region ~750 pc radius Similar to Arp220 but 100 times larger

Mass ~2 1010 Msun Walter et al 2009

J1148+5251: an EoR paradigm with ALMA CO J=6-5

Wrong declination (though ideal for Charlottesville)! But…High sensitivity12hr 1s 0.2mJyWide bandwidth3mm, 2 x 4 GHz IFDefault ‘continuum’ modeTop: USB, 94.8 GHzCO 6-5HCN 8-7HCO+ 8-7H2CO linesLower: LSB, 86.8 GHzHNC 7-6H2CO lines

C18O 6-5H2O 658GHz maser?

Secure redshiftsMolecular astrophysics

ALMA into the EoRSpectral simulation of J1148+5251 Detect dust emission in 1sec (5s) at

250 GHz Detect multiple lines, molecules per

band => detailed astrochemistry Image dust and gas at sub-kpc

resolution – gas dynamics! CO map at 0”.15 resolution in 1.5 hours

HCNHCO+

CO

CCH

N. B. Atomic line diagnostics

[C II] emission in 60sec (10σ) at 256 GHz[O I] 63 µm at 641 GHz[O I] 145 µm at 277 GHz[O III] 88 µm at 457 GHz[N II] 122 µm at 332 GHz[N II] 205 µm at 197 GHzHD 112 µm at 361 GHz

Bandwidth CompressionNearly a whole band scan in one spectrum

Schilke et al. (2000)LSB USB

ALMA Design Reference Science Plan(DRSP)

Goal: To provide a prototype suite of high-priority ALMA projects that could be carried out in ~3 yr of full ALMA operations

Started planning late April 2003; outline + teams complete early July; submitted December 2003; updated periodically

>128 submissions received involving >75 astronomers

Review by ASAC members completed; comments included

Current version of DRSP on Website at:http://www.eso.org/sci/facilities/alma/science/drsp/

New submissions continue to be added.

Example: ALMA Deep FieldStep 1: 300 GHz Continuum Survey

4’ x 4’ Field (3000x3000 pixels) Sensitivity: 0.1 mJy

(5s) 30 minutes per field 140 pointings A total of 3 days

100-300 sourcesDetermine the contribution of LBGs to the IR background

Example: ALMA Deep FieldStep 2: 100 GHz Spectroscopic Survey

4’ x 4’ Field ( 1000x1000 pixels) Sensitivity: 7.5 Jy continuum and 0.02 Jy

km/s for a 300 km/s line (5s) 12 hrs per field 16 pointings (a total of 8 days) 4 tunings

One CO line for all sources at z>2 and two or more at z>6

Photometric redshiftsObtain spectroscopic redshifts

Example: ALMA Deep FieldStep 3: 200 GHz Spectroscopic Survey

4’ x 4’ Field ( 2000x2000 pixels) Sensitivity: 50 Jy continuum (5s)

1.5 hrs per field 90 pointings (a total of 6 days) 8 tunings

Along with Step 2, at least one CO line for all redshifts, two CO lines at z>2

Photometric redshifts

Gas Distribution and Kinematics

Chapman et al. (2004)

Summary: ALMA Deep Field

Fully resolve the cosmic IR background into individual sources and determine FIR properties of LBGs and EROs as well as SMGs

Quantify the properties of high-z dusty galaxies (SFRs, gas content, dynamical mass, etc.)

Map the cosmic evolution of dusty galaxies and their contribution to the cosmic star formation history

Birth of Stars and Planets

The nearest Star Formation regions: ~100 pc from the Sun ALMA Beam at 300 GHz (100 pc): 1.5 AU L1457 was once reported to lie at ~80 pc but now seems to be beyond 300 pc. B68 lies at 95 pc (Langer et al.) Rho Oph has parts as close as 120 pc out to 160 pc Taurus has parts as close as 125 pc out to 140 pc Coal Sack and Chameleon and Lupus are about the same.

The nearest protoplanetary regions lie at ~20 pc from the Sun ALMA Beam at 300 GHz (20 pc): 0.3 AU TW Hya at 56 pc, TW Hya assn is 10 Myr old, not likely to be forming many planets. AU Microscopium, about 14 Myr old, lies only 10 pc from the Sun. Beta Pictoris, 20 Myr old, lies at 17 pc

The nearest debris disks are even closer—around ~10% of nearby stars. ALMA Beam at 300 GHz (3 pc): 0.05 AU Epsilon Eridani lies a little over 3 pc from the Sun Fomalhaut: 7.7 pc

Birth of Stars and PlanetsEvolutionary Sequence Observations—Molecular Cloud Core to Protostar (104 yrs) to Protoplanetary Disk (to ~106 yrs) to Debris Disk (to 109 yrs)

Guilloteau et al 2008Eisner et al 2008 Wilner et al 2002

Vega Dust Disk

Birth of Stars and PlanetsEvolutionary Sequence—Molecular Cloud Core to Protostar (104 yrs) to Protoplanetary Disk (to ~106 yrs) to Debris Disk (to 109 yrs)

Lodato and Rice 2005Wolf and D’Angelo 2005 M. Wyatt; R. Reid

25AU

5AU 160 A

U

Vega Dust Disk

GBT/Mustang Synergy

ALMA Observes Other Planetary Systems

Emphasis has been on optical and infrared wavelengths, as at these wavelengths the Spectral Energy Distributions (SED) of stars and extrasolar planetary systems peak.

ALMA, reaching long FIR wavelengths with great sensitivity and spatial resolution, will image dust and gas in these systems.

We consider the ability of ALMA to observe stars and extrasolar planetary systems in various stages of evolution.

See ALMA Memo 475.

Best Frequency for ALMA Continuum? Define a Figure of Merit For observations of any thermal blackbody (with emission

which goes like -2), the figure of merit that one wants to maximize is X=2/S, where S is the noise at frequency . We want to maximize X because it is proportional to the SNR obtainable. For >350 GHz, need better weather so use pwv=1.5mm below and 0.5mm above this .

Frequency S (mJy) X

230 0.07 76345 0.12 99675 0.85 54

Forming Other Planetary Systems

(1) Infancy. Image the luminous forming stars and planets directly, in emission from stellar photospheres, the gas and dust disk from which the stars formed, and the subsequent assembly of planets from the disk gas and dust.

Disks are small, <900 AU, requiring high angular resolution (1”~140 AU in nearest star-forming regions)

Except for the innermost regions, disks are cold (10-30K at R>100 AU) requiring high sensitivity

Solar-mass stars will have rotation velocities around 2 km/s, turbulence around .2 km/s, requiring high spectral resolution.

The only way to provide high spectral resolution AND high sensitivity is with large collecting area. ALMA.

Disk Structures

The partially resolved dust emission probes now the disk at the scale of our solar system, but is not detectable further out with current millimeter array sensitivity.ALMA is sensitive enough to detect the dust emission in the outer optically thin dust disk.

The CO emission from the outer and from the ~200 AU disk is now detectable. ALMA allows one to map optically thick CO lines at the scale of our Solar System ( ∼ 3 −10 AU), providing information about the gas content and its kinematics; current interferometers do not probe closer in than ~40AU.

Hence one can compare both dust and gas in the same regions. The observations of optically thin lines are still difficult but

possible. Long integration times should be used to detect and map molecules rarer than CO in order to investigate the chemistry of protoplanetary disks.

Forming Planets

(2) Toddler. ALMA will be able to directly detect forming giant planets (‘condensations’) in protoplanetary disks, and the gaps created in these disks as the condensations grow.

‘Theoretical investigations show that the planet-disk interaction causes structures in circumstellar disks, which are usually much larger in size than the planet itself and thus more easily detectable.’ S. Wolf

Formation of Planetary Systems

HST view (left) sees opaque dust projected upon a bright background (if persent). In the ALMA view (above, the dust and the protoplanetary region appear bright.

Wolf and D’Angelo 2005

Nearby Planets (3) Adolescence. ALMA will be able to directly detect very

young giant planets in the nearest star forming regions. Eris, for example, in our own system will be detected in seconds. Integrations times in days for several cases:

Distance(pc)

Jupiter Gl229B Proto-Jupiter

1 1.5 0.01 <1hr

5.7 >1yr 12.5 <1hr

10 >1yr 120 <1hr

120 >1yr >1yr 12.5

Indirect Detection of Mature Planetary Systems

(4) Adult - ALMA will be able to indirectly detect the presence of giant planets around nearby stars through the use of astrometry. ALMA will also be able to detect and image dust/debris disks around nearby stars (zodiacal analogs).

A planet orbiting its central star causes the star to undergo reflexive motion about the barycenter

ALMA would measure this motion accurately in its long configuration at submm wavelengths.

ALMA could detect photospheres of e.g. 1000 stars well enough to detect a 5Jovian mass planet at 5AU. (10 minute integration).

Inclination ambiguities for companions now known could be resolved.

Numerology

Assume: 5AU orbit Three mass ranges: 5 Jovian, Jovian,

Neptunian 10 minute integrations, 345 GHz, 1.5mm

H2OThen: 800, 180, 0 Hipparcos stars about which a

companion might be detected, virtually none solar type.

200, 120, 30 Gliese stars (d<25pc) about which a companion might be detected.

100, 30, 0 of these are solar type stars.

Specific Example

• M dwarfs in solar neighborhood• There are ~90 M dwarfs within 15 pc of the Sun• Planets are hard to detect around them through radial velocity

measurement of spectral lines owing to spectral crowding• A team led by Boss seeks planets through astrometry of these stars at

Las Campanas• For ALMA at 870 microns, e.g. the M4V Barnard’s star at 1.8 pc distance

would have a flux of about 2 mJy. At 15 pc, this is reduced to tens of microJy. Astrometric accuracy of 300mas would require ~20σ measurement, translating to days of integration, unlikely to win the hearts and minds of referees. For an hour’s integration, an ALMA Mdwarf survey to 5pc would seem most reasonable.

Summary

ALMA will image dust and gas in planetary systems at high resolution and sensitivity

Development program will upgrade receivers, implement new bands and enable techniques not within construction scope

Very long baseline interferometry—better astrometric precision

SupraTerahertz operation possible

Contributors to the Millimeter Spectrum

In addition to dominating the spectrum of the distant Universe, millimeter/submillimeter spectral components dominate the spectrum of planets, young stars, many distant galaxies.

Cool objects tend to be extended, hence ALMA’s mandate to image with high sensitivity, recovering all of an object’s emitted flux at the frequency of interest.

Most of the observed transitions of the 142 known interstellar molecules lie in the mm/submm spectral regio. Here some 17,000 lines are seen in a small portion of the spectrum at 2mm.

However, molecules in the Earth’s atmosphere inhibit our study of many of these molecules. Furthermore, the long wavelength requires large aperture for high resolution, unachievable from space. To explore the submillimeter spectrum, a telescope should be placed at Earth’s highest dryest site.

Spectrum courtesy B. Turner (NRAO)

Measurement of Isotope Ratios Owing to the large frequency

separations, measurements of atomic isotope variants in molecules is often more straightforward than measurement in other spectral regimes

Additionally, astrophysical processes may increase fractionation in cold material, favoring observation in rotational molecular lines in cold cloud cores.

Of particular interest are the isotopes of abundant elements in molecules: H (D), 12C (13C), 14N (15N) and O (17O, 18O)

ALMA offers unique capabilities.

How to make Interstellar NH2D etc. • The difference in bonding energy between H and D can provide clues to a molecule’s chemical history• A key reaction deuterating interstellar molecules occurs via exchange of D for H (1) AHn

+ + HD AHn-1D+ + H2 + ∆E• ∆E is the zero-point vibrational energy difference between products and reactants• For A=H & n=2; A=C & n=3; A=C2 & n=2; note ∆E>0• ∆E is 232K, 390 K and 550K, respectively, for H3

+ CH3+ and C2H2

+

• Since [D]/[H]~10-5 large D enhancement can indicate (1) is operating in a cold region• Notice that ∆E is much higher for CH3

+ and C2H2+ than for H3

+ • Molecules which gain their D enhancement from H3

+ should become scarce in warm regions, • Examples

• NH2D is an example of a molecule which should be enhanced only in cold regions, deriving its D from H2D+.

• N2D+ is an example of a molecule which should be enhanced only in cold regions, deriving its D from H2D+.

• DCO+ should be enhanced in cold regions through H2D+ + CO DCO+ + H2 • Those whose D donor is CH2D+ or C2HD+ will show persistent D enhancement in warmer regions

• Some examples:• DCN as an example of possible D inheritance from CH2D+

• Also HDCO, more indirectly through CH2D + O HDCO + H• Alternatively, either could become heavily deuterated in grain mantles and subsequently liberated into

the gas phase.

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Many Deuterating Reactions

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• The actual picture is more complex, with many variations on the basic theme

• The more complex network must be employed to understand multiple deuteration in an ion-molecule framework.

• The actual temperature dependence varies according to the reaction, but those in the same class are generally similar.

Calculations of temperature dependence

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Roueff et al 2005

Previous DCN Observations: General

• Greason (1986) studied DCN enhancement in the ISM

• Observed J=1-0, 2-1, 3-2 and 4-3 DCN; 1-0 and 3-2 H13CN

• LVG modeling provides ratios

• [DCN]/[HCN] remains high in warm sources where [DCO+]/[HCO+] vanishes, e. g. OMC1 (c.f. also Mangum, Plambeck and Wootten 1991 and Schilke 1992)

• Leurini et al. (2006) find like enhancement in Orion Bar

• Infer the presence of CH2D+

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Temperature Dependence of NH2D

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Shah and Wootten 2000

Example: NH2D Thought to form from reactions including N and H2D+

Observed elevated levels of NH2D/NH3 in cold cores are ~30% (Shah & Wootten 2001)

ND2H/NH3 and even ND3/NH3 are observed to be high In one source, N1333 IRAS4A, H2D+ is observed Even D2H+ is observed in another highly deuterated cold

core L1689N. Could arise from grain mantles but

Distribution avoids dust-embedded sources (Shah and Wootten 2001; Roueff et al 2005)

Lower deuteration levels observed in warm cores (Jacq et al 1990)

OMC1 origin partly in Hot Core, partly in ion-molecule chemistry (Walmsley et al 1987; Friedel 1999)

But…even the extended ridge is too warm for H2D+ to be important

NH2D/NH3 can monitor the extent of grain, rather than ion-molecule, chemistryJAO Jan2010

Ammonia Chemistry

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Aikawa et al

Example: Cold Starless Core L1689N

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• HCO+ 3-2, H13CO+ 3-2, HCN 3-2, SiO 2-1, and 1.3mm continuum emission from L1689N (Lis etal. 2002). The square locates the position of the DCO+ 3-2 peak, while the triangle locates the position of the IRAS source.

NH2D 1-0 integrated intensity from L1689N. The beam size of these OVRO Millimeter Array measurements, along with the intensity scale, are indicated. Deuterium enhancement of NH2D/NH3=.07 does not change over scales from 1000 to 10,000 AU in this frigid core; no embedded protostellar object detected.

Wootten and Mangum 1994

N1333 IRAS4A/B Ammonia emission

follows dust, radio continuum poorly at high n in cold sources

Deutero-ammonia entirely fails to follow either dust, warm ammonia, or radio continuum emission.

Source is warm Tsource ~35K (Tbol) Tsource ~60K (Tgas)

As expected, deuterium enhancement in NH3 avoids warm sources. Deuterium enhancement of NH2D/NH3=.07

Here, chemistry dominated by ion-molecule processes

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Choi et al NH3 (2,2); 1.3cm cont

Shah & Wootten (2001) NH2D

The NH2D Spectrum

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• The c-type transitions are the stronger, ΔK=1

• Owing to the proximity of the K=0 and K=1 ladders in energy, there are a number of transitions in the 1cm-3mm range• 86, 50, 18 GHz

for ortho-ammonia

• 110, 74, 43 GHz for para-ammonia

Low Temperature NH2D Spectrum

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• For most cold dense cores, the low-lying lines at 86 and 110 GHz dominate the spectrum, complemented by lines at 49.9 and 74 GHz.• GBT receiver stops at 49.8

GHz!• EVLA performance poor at

50 GHz• B1ext, B2 lines with ALMA• Submm lines observable

with ALMA, SMA• Opportunities, but limited

Spectrum 9K to submm

<3mm 19 K spectrum

Warm Temperature NH2D Spectrum

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• For warm dense cores, the low-lying lines at 86 and 110 GHz dominate but several other lines join the spectrum.• GBT receiver stops at 49.8

GHz but third strongest line at 49.9!

• EVLA performance poor at 50 GHz

• Somewhat higher excitation lines at 18, 25, 43 GHz

• MM, submm lines observable with several interferometers

• Opportunities quite good, but are there sources???

Spectrum 75K to submm

<3mm 75 K spectrum

Deutero-ammonia in OMC1

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Higher energy lines also• Walmsley et al. 1987 414-404 (para)

and 313-303 (ortho) lines • Groddi et al 2009, Favre et al.

GBT Qband 313-303 (para) line at 65K

• High energy (261K) 524-514 line in Friedel data originates in Hot Core alone

• Deuterium enhancement of NH2D/NH3=.003 (Walmsley et al)

• Mixed message—certainly a grain component, possibly no ion-molecule source (at least in the hot gas)?

• Ion-molecule timescale for released NH2D~1000yr

IRAM PdBI Observations from T. Jacq, Favre, Brouillet, 110 GHz low energy line

• Compact ridge source clear• Some hot core emission

DCO+

A line appears at the correct frequency in the Turner 2mm survey, at about half the strength of a similar line in the nearby Ori-S source

Analysis suggests [DCO+]/[HCO+]~.001 or so with large uncertainty.

DCO+ should be enhanced in cold regions through H2D+ + CO DCO+ + H2 Operates at low (<25K) temperature only Would not expect to see this in OMC1, hot cores

• Also DCO+, more indirectly through CH2D+ + O DCO+ + H• Could operate in warmer (35-50 K) environments• Can account for observations for X(CH2D+)~10-10,

X(O)~10-6 JAO Jan2010

DCN in the Orion Bar The ‘Bar’ is the interaction site between hot stars and the

molecular cloud Leurini et al. (2006) found DCN in APEX 1mm survey of the Bar Interesting target for CH2D+ search

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Leurini et al 2006

Leurini et al 2009

Previous DCN Observations: Other ‘Hot Core’ Sources of DCN

S255-SMA1 THC3N~100K TH2CO ~>50K DCN (3-2) emission peak Suggests hot core like

object with strong DCN. NGC6334N

Four sources, two hottest (T~100K) show DCN (3-2) emission

Cooler source (T~33K) shows none (but few other lines either!)

Suggests hot cores with DCN emissionJAO Jan2010

Cyganowski et al.

Brogan and Hunter (PC)

Summary: D Astrochemistry

Deuterium becomes concentrated in molecules in the cold environments of dense clouds

The degree of concentration provides a probe of chemical processes

It is observed in cold gas and in warm regions where ices in which D was concentrated are being liberated by star formation

ALMA’s First Ten Years

A feature of ALMA Operations is Development

Possibilities: Finishing unfinished frequency bands Expand collecting area to recommended 64 x

12m telescopes Expand resolution by adding VLB capability Addition of new bands—more challenging,

but a ‘Band 11’ seems unusually promising given the thrust of science, the excellence of the site and the promise of the first antennas

J1148: A possible (not from Chajnantor!) H2 observation

An early (z=6.42; 0.8Gyr) massive and exteded region of tremendous star formation

~1000 Msun/yr/kpc2 Region ~750 pc radiusSimilar to Arp220 but 100 times larger

Mass ~2 1010 Msun

Opening Up the Dark Side of Reionization

After R. Barkana

Creation of the Metals

When chemistry got interesting

(H3+, H2D+, H2, HD notwithstanding)

ALMA should be able to monitor the creation of

• O ([O I], [O III], OH, H2O)• C ([C I], [C II], CO, CH,

CH+,13C)• N ([N II], NH, N2H+)

Dark Side of Reionization

ALMA 1 hr, 5σ, 300 km/sSingle to score of clouds of108Msun

B11B10

After Appleton et al 2009

THz windows

Next decade’s focus:• Herschel• SOFIA• ALMA• CCAT• SPICA

T. Hunter

Some Atomic and Light Molecule THz lines

Spectral lines in THz windows from CCAT

T. Hunter

THz Region: Key to Chemical Evolution

Molecular Hydrogen cooled the first star-forming regions; at z>6 lines fall, with breaks, in windows accessible with ALMA

The first now-abundant atoms were O, C, N, F

Atomic and molecular lines of C—CO CH CI and CII are available for z>1

Atomic and molecular lines of O— OH H2O OI and OIII are available for z>4

As these elements were produced, they cooled the gas

www.alma.info

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership among Europe, Japan and North America, in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere, in Japan by the National Institutes of Natural Sciences (NINS) in cooperation with the Academia Sinica in Taiwan and in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC). ALMA construction and operations are led on behalf of Europe by ESO, on behalf of Japan by the National Astronomical Observatory of Japan (NAOJ) and on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI).

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