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10 January 2006 AAS EVLA Town Hall Meeting 1 The EVLA: A North American Partnership The EVLA Project on the Web http://www.aoc.nrao.edu/evla/

10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

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Page 1: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

10 January 2006 AAS EVLA Town Hall Meeting 1

The EVLA: A North American Partnership

The EVLA Project on the Webhttp://www.aoc.nrao.edu/evla/

Page 2: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

N ational R esearch C ounci lC anada

C onsei l national de recherchesC anada

New Science Impactof the EVLA Supercomputing Correlator

P. Dewdney Herzberg Institute of AstrophysicsNational Research Council Canada

M. P. Rupen National Radio Astronomy Observatory

Page 3: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

N ational R esearch C ounci lC anada

C onsei l national de recherchesC anada

Key EVLA Processing Capabilities

Deep ImagingPolarization

8 GHz Bandwidth (dual polarization). Full polarization processing. Wide-field imaging.

Narrow spectral linesWideband searches

16,000 channels at max. bandwidth (BW). >105 channels at narrow BWs. Spectral resolution to match any linewidth. Spectral polarization (Zeeman Splitting).

8 tunable 2 GHz wide bands. Each band - 16 tunable sub-bands. Sub-band – independent spectral resolution. Simultaneous line and continuum.

Flexibility Many resources

High time resolution 1000 pulsar “phase bins”. “Single-dish” data output to user

instruments. Very fast time sampling (20 s).

Page 4: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

Star-Forming Galaxies at High Redshift

• Enabled by enhanced sensitivity of EVLA.

• Complementary to ALMA & Spitzer.

• K-correction compensates for z-losses in the 45 GHz band.

• Resolution 50 mas. (200 pc @ z=10).

• Imaging: 1 arcsec over 30 arcmin @ 1.5 GHz.

• EVLA/ALMA gives complete galaxy SED’s:– 3 orders of magnitude

of frequency,– Large range of redshift.

Arp220 SED scaled to high redshifts.

NGC 3690 (optical)

Spitzer

non-thermal/AGN

ionized gas

dust

Page 5: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

CO Surveys of High-z Star-Forming Galaxies

ARP 220 (optical)

• EVLA sensitivity (red line) in 8 hrs (1 ).

• Detects (J=1-0, 2-1, 3-2, 4-3).

• More transitions at high z.• Precise redshift not

necessary in advance.• Spectral resolution will

match channel to line-width.

• Other lines: HCN, HCO+…

COJ=3-2

Z = 6.42

Peak ~ 0.6 mJy

This is a struggle!

Page 6: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

N ational R esearch C ounci lC anada

C onsei l national de recherchesC anada

Setup for CO Z-Search

• 40-50 GHz band provides lowest redshift.

• z = 1.4 to 1.9 for J=1-0.

• z = 3.8 to 4.8 for J=2-1.

• v ~ 5.0 km s-1 (1 MHz).

• 200 km-s-1 galaxy would occupy ~40 channels.

• Interferometry• High resolution imaging.• Good spectral baselines. 2 , 1 , 0 .5 , ... G H z O bs e rv ing B andw id ths

16 S ub -B ands (s how n w ith de fau lt pos itions and w id ths )

1 2 3 4 ... 15 16

R ight P o la r iza tion L e f t P o la r iza tion

48-50 G Hz48-50 G Hz

46-48 G Hz 46-48 G Hz

44-46 G Hz44-46 G Hz

42-44 G Hz 42-44 G Hz

2-41-2 4-8 8-12 12-18 18-27 27-40 40-50L S C X U K Ka Q

G Hz

S k y F re q u e n c y B a n d s

8 tu n ab le IF B an d s

Note: S ub-bands can beseam lessly jo ined acrosseach observing bandwidth.

Page 7: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

• ~30 H+ radio recomb. lines in one observation. • “Stack” lines to improve sensitivity.• H+, He+, C+ recomb. lines.

• EVLA resolution provides images of:

gas density, temperature, metallicity, B-fields (Zeeman).

• Sensitivity (12 hr, 5): Sline ~ 0.1 mJy (stacked, integral) B ~ 150 Gauss.

• Orion, W3, Gal. Center …

Magnetic Fields in Star-Forming Regions

2-41-2 4-8 8-12 12-18 18-27 27-40 40-50L S C X U K K a Q

GH z

S k y F re q u e n c y B a n d s

R ig h t P o l'n Lef t P o l'n

8 M H z

25 km/s

H II

H eIIC II

(8 0 0 k m /s )

1 0 2 4 chan 's.R ec irc . fac to r = 1 6 v = 0 .8 k m /s

C o ntinuum S e tup C o ntinuum S e tup

Page 8: 10 January 2006AAS EVLA Town Hall Meeting1 The EVLA: A North American Partnership The EVLA Project on the Web

N ational R esearch C ounci lC anada

C onsei l national de recherchesC anada

Hundreds of Spectral Lines• Kaifu, et al., TMC-1, 2004.• Nobeyama spectral scan.• 414 lines (8 to 50 GHz)• 38 species.• Some likely to show

Zeeman splitting.• “D-array” EVLA

– Resolution,– Spectral baseline stability,– Imaging.

• EVLA can observe 8 GHz at one time – an average of 80 lines --- at 10 km/s velocity res’n (30 GHz)

• EVLA Correlator can “target” many (~60) lines at once.

2-41-2 4-8 8-12 12-18 18-27 27-40 40-50L S C X U K Ka Q

G Hz

S k y F re q u e n c y B a n d s

TA*

8 GHz