11 september 2008 nsf arecibo radio astronomy chris salter for murray lewis

11 September 2008 NSF

ARECIBO

RADIO ASTRONOMY

Chris Salter for Murray Lewis


Across whole Arecibo pgm.

• Mass-range investigated dynamically– ~56 orders of magnitude– Micro-meteorites -- asteroids -- neutron stars --

-- galaxy clusters

• Time duration: ∆t > 23 orders of magnitude– Crab giant pulses 10-9 sec; Galaxy Evoln. > 109 yr

• Magnetic field: B > 20 orders of magnitude– Mercury null; ISM; to Magnetars > 10^13 gauss


Traditional Arecibo topics• Pulsars -- (pALFA), timing MSP

• 21 cm HI– Extra-galactic {alfalfa, AGES, (AUDS), ([ZoA]) }

– Galactic {Disk-Halo, (I-gALFA), [TOGS,TOGS2,GALFACTS2]}

• OTHER– Magnetic Fields {(GALFACTS), (ULIRGs) }

– VLBI

– Multi-UGC, CGCG, SDSS, IRAS, 2MASS, (GLAST)}

– Molecular-line {Arp 220, ULIRGs}


ALFA: A Camera for Arecibo

2004

•Installed 2004 Apr•Surveys initiated Feb 2005•7 beams x 2 pol (linear) = 14 “pixels”

•1225-1525 MHz full range•Unmatched sensitivity (SEFD = 2.4 to 3 Jy)

•3.3’ x 3.8’ beams on 11’ X 13’ ellipse

•Unprecedented capability for mapping the sky

•Survey consortia self-organized by community


Pulsars

• Discovery -- (pALFA)

• timing, MSP timing, gravitational-waveenergy density

• timing noise investigations

• high-time resolution studies

• tests of general relativity

• physics of extreme environments (B, Eqn. State)

• ISM studies (using pulsars as probes of ISM, etc)

• precision astrometry (parallaxes, proper motions, etc)

• pulsar time scales (inertial & dynamical)


J1903+03272.15 msec

95 d orbit

e 0.43667

1.74±0.04 Mo


Traditional Arecibo topics

• Pulsars -- (pALFA), timing MSP





HI STUDIES

• Trace phase change from ionized to neutral species

• HI eliminated via phase change to molecular species

• Traces accumulation of visible baryons into galaxies -- Tully Fisher Relation


BTF from Resolved Rotation Curves

Need aperture synthesis HI maps - limits sample sizes

NRAO/AUI and NOAO/AURA/NSF Rector et al.

M33 starsHI

r, kpc10 30 50

100

200

300

V, km/s

HIH

HI b

d

Vrot

h

b ϒ*

KS 2005


The Baryonic Tully-Fisher Relation

M*

Vrot (km/s)

Md

McGaugh et al 2000

100Vrot (km/s)

30030 100 300301

09

10

111

07

10

91

011

10

7Stellar TF BTF

M* =ϒ*L

M d =M* +1.4MHI

Coverage over CompletenessPhilosophy

(Mo) (Mo)

(colors)

H K’ I B


Arecibo as an HI telescope

in the coming era of active SKA survey- optimized pathfinders (ASKAP, MSKAP)

to be followed by the SKA

whence Arecibo?

The mid-range SKA is a 0.3-3 GHz+ facility

That exactly matches Arecibo, so

Arecibo’s science is SKA precursor science


• Looking at large redshifts

=> evolution in TF relation

• Looking for local very low mass objects => alfalfa

Exploit Sensitivity by


A Pilot Survey of HI in Field Galaxies at z ~ 0.2: Catinella et al ApJL


Text

~5300 galaxies from alfalfa: RA 7.5 - 16.5 hr, dec 12 - 16°


Parkes HIPASS survey: Zwaan et al. 2003

?•Previous surveys have detected few (if any) objects with low HI.

•At low mass end, HIMF estimates differ by >10X:

Rosenberg & Schneider (2000)

versus

Zwaan et al. (1997)

HIMF


Traditional Arecibo topics

• Pulsars -- (pALFA), timing MSP





TOGS HI map from commensal observations in fall 2007

Dec. 21 - 26°; RA 3hr - 23 hr


Magnetic Fields

GALFACTS


VLBI and AreciboThe impact of Arecibo’s sensitivity

• Arecibo added to the VLBA => 4.5 times better sensitivity (Day & Momjian 2005).

http://www.naic.edu/


VLBI Highlights Post-Painting MK5A Disk-recorded: Three successful Mk5A disk-based

runs using L, C and X-band, with HAS, EVN & Global network. These represent; (1) a study of the Zeeman effect for compact components in ULIRGs, (2) jet and counter-jet emission in the giant radio galaxy, NGC315 and, (3) measuring the expansion velocity of SN2008D associated with the transient X-ray source in NGC2770 (Target of Opportunity).

E-VLBI test over the existing OC3 (155Mbps-shared with UPR) line:

Arecibo data arriving at JIVE

@64Mbps

@128Mbps

Fringe amplitude for 64Mbps

Jb - Tr

Jb - Wb

Jb - Ar Tr - Wb

Tr - Ar Wb - Ar

Fringe amplitude for 128 Mbps

Jb - Tr Jb - Wb

Jb - Ar Tr - Wb

Tr - Ar Wb - ArQSO 3C395


Exploiting 1 - 10 GHz

• Molecular line searches (Galactic starting)

• Molecular line searches extragalactic

ULIRGS, recent success


A Spectral Scan of Arp 220:1.1 – 10 GHz

Arp 220 is a star-burst galaxy at a distance of 250 Mly.

It is forming stars at 100-times the rate of the Milky Way.

It is the result of a collision between 2 galaxies now in the final stages of merging.

(HST:Optical)

(VLA:Radio Wavlength 6cm)


The Spectrum of Arp 220 – Prebiotic Molecules

Methanimine (CH2NH) observed for the

first time outside of the Milky Way (where it has only been observed in one source!)

This is probably a maser emitter.

“Bending” transitions of HCN observed for the very first time in the radio region.These lines are at L-, C-, C-Hi & X-band.

STOP PRESS:

HCN at S-band.

11 september 2008 nsf arecibo radio astronomy chris salter for murray lewis

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