ALMA Science Results

advertisement
Fourth in a series…
www.almasc2014.jp
Summary of External Galaxy Talks
Al Wootten
1
ALMA Science Results
2
ALMA Science Results
Themes
• ALMA’s sensitivity and directivity enable studies of nuclear
regions of galaxies
– Still difficult to disentangle inflow from outflow; in some cases
motions were kinematically complex
– One needs a better measure of mass—for most objects only a limit
could be established
– Excellent prospects for measuring BH masses dynamically
• ALMA’s broad spectral grasp enables parallel excitation
analyses among up to ~40 species.
3
ALMA Science Results
Revolution in Astronomy
• Galaxies and Galactic Nuclei I
– 9:45 - 10:15 (invited) Quantifying key components in
galaxies using ALMA: molecular clouds, dust, outflows, and
supermassive black holes
• Kotaro Kohno, University of Tokyo
– Star formation converts HI through molecules to stars; ALMA studies the
intermediate step.
– Feedback: spatially resolved sensitive imaging critical for understanding
feedback; ALMA provides this.
– Combined ALMA data with Nobeyama 45m for M83 image.
– NGC1808
– Arp 220: 434 micron imaging with ALMA reveals fine structure of its two
nuclei. West nucleus requires AGN owing to high luminosity surface density.
– NGC5044 group.
4
ALMA Science Results
• Kohno (cont)
– Outflows and Inflows in galaxies—central kinematics.
– N1433-Combes et al.. CO deviates from ordered rotation: an outflow.
– NGC1566 shows no outflow. Many talks on feedback and outflow at this
meeting.
– Measuring supermassive black holes with ALMA. Kinematic signature within
rotation curve.
– Submm water maser lines offer promise for measuring central kinematics of
galaxies (Hagiwara)
– 10:15 - 10:30 The ALMA view of the starburst in NGC 253
• Alberto Bolatto, University of Maryland
– Nuclear starbursts thought to be especially important at z~1-2 in galaxies.
What drives them? What quenches them? Nearby NGC253 offers a nearby
example. Hot xray radn seen by Chandra. ALMA view?
– CO at high velocities correlates with the Xray streamers. Narrow, very
turbulent short lifetime molecular structures.
– Streamer bases lie near expanding molecular shells which may initiate them.
– Outflow likely greater than 9 Msun/yr--may be lost but may be recycled.
5
ALMA Science Results
– 10:50 - 11:05 Radio jets clearing the way: watching
feedback in action in the Seyfert galaxy IC 5063
• Raffaella Morganti, ASTRON, Kapteyn Institute
– H2 imaged with VLT, broad component near the jet. ALMA: 100pc resolution
in CO 2-1 wraps around radio continuum well.
– Kinematics: Clear correspondence to disturbances along the jet, deviates from
rotation curve. Model: jet expands in clumpy medium
– 11:05 - 11:20 How do you drive molecular outflows?
ALMA’s view of AGN feedback in NGC 1266
• Timothy Davis, University of Hertfordshire
–
–
–
–
Form: heats hot gas in galactic halos to prevent cooling.
OR direct: removes star forming ISM
Is it photon driven or jet driven?
N1266 is most gas-rich early type galaxy in local Universe. Alatalo: CO shows
outflow 500 km/s. Losing gas >110 Msun/yr. Chemistry can distinguish the
form of the driver.SiO strong: shocks?
– Weak ionized lines. Outflow seems to be powered by a nascent AGN jet.
6
ALMA Science Results
– 11:20 - 11:35 Ballistic molecular rain powers cold black
hole feedback in a cool core brightest cluster galaxy
• Grant Tremblay, Yale University
– Thanks for making ALMA accessible to optical/Xray observers.
– A2597: 10 Msun/yr. z=.08. Cool core brightest cluster galaxy. Molecular gas
follows ionized gas. CO2-1 with ALMA shows 2E9Msun cool gas. See a
molecular fountain--molecular bubbles inflated by jet, permeated by young
stars. Material slowly returns along filaments.
– Infalling gas seen which can power the fountain.
– 11:35 - 11:50 The molecular gas outflow of NGC 1068
imaged by ALMA
• Santiago Garcia-Burillo, OAN-IGN
– Outflow in ionized gas, also in molecular circumnuclear disk. Dense tracers
imaged to r~2kpc at 20-35pc resolution.
– Find an off centered 200pc ring around AGN/ Kinematics--rotation and
streaming. Find a molecular outflow at the circumnuclear disk.
– Half of mass in CND is involved in outflow driven by AGN feedback. star
formation cannot drive this outflow.
– Many species also imaged.
– Radiation pressure on dust could drive the outflow.
7
ALMA Science Results
– 11:50 - 12:05 ALMA observations of a candidate molecular
outflow in obscured quasar SDSS J1356+1026
• Ai-Lei Sun, Princeton University
– Redshift z=.123. N nucleus a galaxy, S nucleus less. Radioquiet. ALMA provided resolutions to 0.77kpc. No CO at
ionized outflow; gas is in N nucleus with 1kpc tidal arm, very
broad line.
– Velocity too high to be rotation--outflow?
– Star formation rate <21 Msun/yr. S galaxy passes by N galaxy
every 10^7 yrs. Perhaps at perigalaxion the extended ionized
flow is stoked.
8
ALMA Science Results
• Galaxies and Galactic Nuclei II (chair: Alberto Bolatto)
– 13:30 - 14:00 (invited) Galaxies and galaxy nuclei with ALMA
• Susanne Aalto, Chalmers University of Technology
– Vibrationally excited molecules probe central regions but HCN and HCO+ are very
optically thick owing to steep T gradient and large column
– Even may see self absorption in vibrationally excited lines. If starburst, a very hot
one. Results consistent with a supermassive Black Hole accreting near Eddington
limit.
– NGC1377: extreme FIR excess, radio-quiet with strong molecular outflow which
could clear it in a few megayears. Driving source unknown--very young starburst
or black hole?
– ALMA Cycle 2: flow flips in sense near nucleus. Origin unclear?
» Perhaps a jet in the plane of the sky precessing?
» NGC3256 offers a similar example.
– At the other end of the scale Mkn 231. Many molecules flowing at high velocity.
– ALMA reveals stunning richness in AGN and starburst nuclei in many lines.
– Extremely dust obscured nuclei show self absorbed emission from HCN, HCO+
and ALMA can detect the vibrational lines from them to probe near the central
engine.
9
ALMA Science Results
– 14:00 - 14:15 An ALMA spectral scan of the obscured luminous
infrared galaxy NGC 4418
• Francesco Costagliola, Chalmers University of Technology
– Obscured LIRGS. T>100K, l<100pc, SFR>10Msun/yr, N(H2)>10^24
cm^-2 so only radio and submm radiation can escape.
– How much radiation comes from star formation how much from
active nuclei? Observe many spectral lines and compare them to
probe excitation.
– Species often optically thick. Multiband scans provide many lines.
175GHz scan of NGC4418. Similar beam from 85-360GHz, The
galaxy has high silicate absorption at ten microns. Narrow
molecular lines, radio quiet.
» Lines provide 30% of flux
» Reach line confusion limit quickly; fit whole spectrum at once.
Lots of HC3N, also vib-excited variant. Also HC5N. 40 molecules
– Vibrationally excited HCN, HNC, HC3N probe the 5pc size source at
center. Temperatures vary >100K. A new chemistry?
– Can fit 90% of emission from lines.
10
ALMA Science Results
– Distributions of molecules in the circumnuclear disk and surrounding
starburst ring in the Seyfert galaxy NGC 1068 observed with ALMA
• Shuro Takano:
– NRO45m 3mm survey laid foundation for ALMA survey. N1068: Syf 2 nucleus.
14.4Mpc distance so 1”=72pc. Circumnuclear disk has two knots.
– Selected spectral windows based on 45m data. In some lines, the ring
dominates, in others the CND is also promonent. Astonishment no 1:
Methanol differs in the ring from 13CO. Astonishment 2: Some complex
species concentrate in CND where X-rays are strong: HNCO, CH3CN.
Astonishment 3: Ten line distributions obtained with an hour time in Cycle 0
– 15:00 - 15:15 Diffuse and dense gas in nearby luminous merging
galaxies
• Toshiki Saito, University of Tokyo
– Observed VV114, N3110, N1614 with ALMA. Some ALMA Cycle 2 results
shown.
– CO 6-5 is more compact than low J CO.
– The CO 6-5 traces intense nuclear star formation.
– Claims that shocked regions traced in CS and CH3OH lines.
11
ALMA Science Results
– 14:45 - 15:00 ALMA explorations of warm dense molecular gas in nearby
LIRGs
• Kevin Xu, California Institute of Technology/IPAC
– .4mm CO 6-5, continuum
– How does warm gas distribute in LIRG nuclei
» Correlate with star formation? Are outflows important? When do AGNs
dominate heating of gas and dust?
– NGC34 and NGC1614. Former has CO in unresolved core, warmer gas. AGN<19%.
In N1614 no nuclear emission is seen. http://arxiv.org/abs/1410.6982
– NGC34: rotating disk kinematics. Also emission from H13CN 8-7 in wing. For the
latter, need mechanical heating in models. Or: it is not H13CN but a 400 km/s CO
outflow.
– NGC1614. No compton-thick AGN.
12
ALMA Science Results
– 16:15 - 16:35 (17+3) The molecular environment star formation and cluster
dissolution across dynamically distinct environments in NGC 1097
– (allocated 5 minute extension to introduce a cancelled talk by K. Scott)
• Kartik Sheth, National Radio Astronomy Observatory
– 103 pointing mosaic was difficult to deal with for imaging.
– Star formation can vary by 1000x from ring to bar to disk.
– What triggers and controls it?
– In the bar, No star formation but lots of molecular gas. Here the bar
pattern speed is 36 km/s/kpc. Star formation is absent for dOmega>35
km/s/kpc. Fast shocks destroy gas.
– HST data appears to show young clusters in center. Star formation and
spurs are seen, undetected in CO. Dust is detected only in the star forming
ring.
– Kim Scott-Evolution of molecular gas fraction. CO 3-2 in star forming
galaxies from COSMOS 100% detection rate. intermediate redshift.
Complex line profiles.
– Large mass-selected samples for fH2 evolution with redshift being
observed in Cycle 2. Scoville, Scott, Sheth, Schinnerer.
13
ALMA Science Results
– 16:35 - 16:50 ALMA and VLA measurements of frequencydependent time lags in Sgr A*: evidence for a relativistic
outflow
• Christiaan Brinkerink, IMAPP, Radboud University Nijmegen
– What is SgrA* exactly?? Accretion flow? Jet? SED appears
partially self-absorbed synchrotron. Usually this type has a jet.
– Measured time lag in radio emission. Some part of jet is optically
thick at some frequency. High frequencies closer in, see those
first.
– ALMA maps of the mini spiral dynamic range 4000 total time on
source 6 mins. 3mm, 1mm, .8mm observed. Show varying
spectrum.
– More variation in flux at higher frequencies.What is the
inclination angle? Use size measurements at high nu with VLB
– Combine observations. Model them--can get moderately
relativistic outflows--unresolved jet? Inclination still uncertain.
14
ALMA Science Results
– 16:50 - 17:05 Ionized gas observations toward a nearby
starburst galaxy NGC 253
• Kouichiro Nakanishi, National Astronomical Observatory of Japan
– H recombination line observations, a fundamental probe of ionized gas in
intrinsically weak lines made accessible by ALMA.
– H40alpha at 99GHz. Compare to VLA H53alpha and H92alpha. Telectron is
estimated from data. Center has lower Te 6500K, NE region is 9000K.
– Metallicity also important (electron donors).
– Ionized gas velocity gradient at galaxy center is opposite to that of molecular
gas.
15
ALMA Science Results
– 17:05 - 17:20 Star formation and turbulence in the
Antennae overlap region
• Cinthya Herrera, National Astronomical Observatory of Japan
– Galaxy interations are key components of galaxy formation and evolution.
Most of star formation occurs in very compact (few pc) massive (>10^5 Msun)
super star clusters. What triggers their formation?
– Cycle 2 data could not see SiO but did get 13CO 2-1. Combine with H2
emission data from VLT. H2 kinematics like CO.
– What power H2? Line ratios suggest shocks do the excitation. Where H2/CO
is highest is a unique source. An early supercluster?
– Also detected unresolved HCN, HCO+ J=4-3 data. FWHM of H2, CO lines is 90
km/s. Looks like H2 cloud is not gravitationally bound.
– There are 5 SSCs in the overlap region.
– What is the dynamical state of the H2 compact source? We do not see the
SiO J=5-4 shock tracer. We expected a source clearly detected.
16
ALMA Science Results
– 17:20 - 17:35 Star formation in extreme environments: the
case of the prototypical blue compact dwarf II Zw 40
• Amanda Kepley, National Radio Astronomy Observatory
– Metallicity and star formation rate surface density critical to understanding; blue
compact dwarfs are ideal labs to study these effects.
– IIZw40 has low metallicity (0.2 solar) and high star formation rate (0.25 Msun/yr).
But low metals makes low dust, gas dissociates
– ALMA provides 24pc resolution at high sensitivity. Data at 3mm, 1mm, .8mm,
expecting .4mm data. Several giant molecular clouds identified.
– Clouds follow size-linewidth relationship generally. CO-H2 conversion factor 5x
that in Milky Way.
– Molecular gas left in IIZw40 is equal to the mass of its young stars. Can form one
more 30Dor-sized cluster.
17
ALMA Science Results
– 17:35 - 17:50 WISDOM: mm-wave interferometric survey
of dark object masses
• Martin Bureau, University of Oxford
– Aims: mass assembly history and feedback. Why molecular gas--best tracer
of circular velocity in galaxies. Best tracer of dynamical mass.
– Get masses of supermassive black holes through CO dynamical
measurements. NGC4526 high resolution CO imaging. CARMA data.
– Fit to CO rotation curve shows a black hole of 400 million suns. Took 50 hrs of
highest resolution A array data. ALMA far faster
– No Cyc 2 data yet. Should get three objects soon… Could get a thousand
black holes with ALMA.
– 17:50 - 18:05 Investigating the evolution of merging
galaxies via cold molecular gas
• Junko Ueda, National Astronomical Observatory of Japan
– Locally spirals appear to combine, ellipticals result. At z~.65 however, many
more peculiar galaxies, which must have evolved to present-day spirals.
– Sample of optically selected merger remnants. ALMA observations along with
SMA, CARMA. 24 sources modeled.
– 54% extended disks.
18
ALMA Science Results
ALMA Postdoctoral Symposium
• At NAOJ, Mitaka 13-14 Dec
– http://almaintweb.mtk.nao.ac.jp/~cherrera/Home.html
• 26 participants from across ALMA—including
Jen, Amanda and Drew
• 22 talks on a variety of topics
19
ALMA Science Results
Summary?
• ALMA’s sensitivity and directivity enable studies of nuclear
regions of galaxies
– Still difficult to disentangle inflow from outflow; in some cases
motions were kinematically complex
– One needs a better measure of mass—for most objects only a limit
could be established
– Excellent prospects for measuring BH masses dynamically
• ALMA’s broad spectral grasp enables parallel excitation
analyses among up to ~40 species.
• Whither ALMA Development?
–
–
–
–
20
Broader spectral coverage—faster data acquisition?
Complete the spectral coverage?
Longer baselines (e.g. LLAMA project, EHT)?
Interpretive and analytical software?
ALMA Science Results
ALMA 2030
• Switch to pdfs…
21
ALMA Science Results
ALMA OBSERVATIONS OF THE ANTENNAE GALAXIES. I.
A NEW WINDOW ON A PROTOTYPICAL MERGER
Bradley C. Whitmore et al. 2014 ApJ 795 156
• Filaments identified with
beads-on-a-string
morphology
• Clear evolutionary sequence
emerges
• Diffuse GMCs beget
protoclusters beget
embedded clusters beget
emerging clusters beget
young clusters beget old
clusters.
• The lifetime of a GMC in a
star formation region is of
order 10 Myr
22
(L) CO J=3-2 knots, (C) 3.7 GHz emission, (R) optical
clusters in the Long-Thin filament
Green contours (20, 40, 60 K km s−1) show CO emission;
;
and orange provides information about the optical
clusters.
ALMA Science Results
Starburst Nuclear Ring Imaged by ALMA in NGC1614
• ALMA resolved CO J=6-5 and 435m continuum emission in
this 68Mpc distant LIRG.
– Knots in a molecular ring at 100 pc<r<350 pc are clumpy, broad (dV~40
km/s)
– Star formation rate in the ring is ~100 Msunyr-1 kpc-2
– Absence of nuclear emission rules out a Compton-thick active nucleus
– ΣSFR to Σgas is 10x expectations from KS, perhaps caused by outward
propagation of the central starburst
Xu et al 1411.1111
23
ALMA Science Results
Download