AUSAC Meeting · March 17-18, 2008

Radio Astronomy -- Other Than ALFA Surveys

Chris Salter (NAIC/Arecibo Observatory)

AUSAC Meeting · March 17-18, 2008

The Rules of the Game• Pre-Nov 2006: -- 50% of R.A. telescope time for non ALFA-

survey astronomy (~2400 hr per yr). -- Rx available: 327, 430 & 610 MHz; LBW,

SBW, SBH, CB, CBH & XB. • Post-Nov 2006: -- 20% of R.A. telescope time for non ALFA-

survey astronomy (~750 hr per yr). -- Rx available: 327 & 430 MHz; LBW, CB & XB; (SBW, SBH & CBH on “campaign”

basis).

AUSAC Meeting · March 17-18, 2008

Pulsar Study: The “Planets Pulsar” Alex Wolszczan is completing a 17-yr study of the “planets pulsar”, PSR B1257+12. His timing fits includes;

• All PSR parameters

• Astrometric parameters

• Three planets (including the mutual perturbations of Planets b & c)

•DM variations (3rd panel).

Highlights of 17-yr Study of B1257+12

• First exoplanets.

• First detection of planets in mean motion resonance (MMR 3:2).

• First multiplanet system.

• First terrestrial-mass system.

• First dynamical analog of the inner solar system (scaled down by a factor of ~2).

430-MHz Raw Residuals

1400-MHz Raw Residuals

Residuals including DM Variations

Dispersion Measure (DM) Variations

AUSAC Meeting · March 17-18, 2008

Continuum StudiesCombining DRAO Interferometer and Arecibo 400-MHz data, Kronberg et al. have imaged an 8º 8º region in the P-P supercluster to examine the nature of the low-level emission. The Arecibo images were CLEANed before being combined with those from DRAO. The angular resolution of the image is 10 arcmin.

Minchin et al observed galaxies from the Scuba Local Universe Galaxy Survey (SLUGS) at 3, 5, 7 & 9 GHz to characterize their synchrotron emission to find its contribution to their 850 µm fluxes. This allowed corrected estimates of their cold dust masses.

HI emission from Disk Galaxies at z~0.2

Sample selected from SDSS according to redshift (0.16<z<0.27), optical (Hα) emission line strength, inclination (>45o), disk morphology, and relative isolation.

Observations in standard position-switching mode, L-band wide.

41 galaxies targeted.

26 detections + 8 tentative ones

HI mass 3 − 8 1010 Mּס

ON-source integration time between 1 and 4 hr per object

280 hr telescope time including overheads.

B. Catinella (MPA, Arecibo), M. Haynes, R. Giovanelli (Cornell), J. Gardner, A. Connolly (UPitt)

SDSS ARECIBO z=0.195

0.203

0.219

SDSS ARECIBO z=0.224

0.245

0.262

Catinella et al. in preparation

Gas fraction vs stellar mass

Black: Virgo cluster (GOLDMINE + ALFALFA, Gavazzi et al. 2008)

z ~ 0

z ~ 0.2

Catinella et al. in preparation

Evolution effects?

Need a fair sample of massive (HI, M*), z~0 galaxies for comparison!!

Virgo cluster

AUSAC Meeting · March 17-18, 2008

HI from Black-hole Host Galaxies

Ho, Darling & Greene

Ho, Darling and Greene have made a large survey of 154 nearby Type-1 (broad-lined) AGNs whose black-hole masses and accretion rates are known. This enables them to constrain a number of properties of relevance to the relationship between BHs and their hosts. HI was detected in a high percentage of the targets.

HI spectra yield:

• Maximum rotation velocity of disk.

• Estimate of galaxy luminosity via Tully-Fisher.

• Using the optical disk size, an estimate of the dynamical mass of the galaxy.

• A first-order estimate for the cold-gas content of the galaxy.

AUSAC Meeting · March 17-18, 2008

HI from Black-hole Host Galaxies II

Ho, Darling & Greene

Black-hole mass vs Dynamical mass of host galaxy

B-band Tully-Fisher relation forsample. Apart from larger scatter, No gross differences between activeAnd inactive galaxies.

Distribution of MHI/LB for thehost galaxies and a large sampleof inactive galaxies. Similar distribution for later types, but early type active galaxies appear more gas-rich.

AUSAC Meeting · March 17-18, 2008

Molecular Line Studies: IRAS 18566+0408

• No. of Galactic H

2CO masers = 7

• A recent Arecibo H2CO survey of low-mass star

forming regions showed these masers are exclusively associated with high-mass star formation.

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The H2CO maser in IRAS 18566+0408 was

discovered at Arecibo in 2002. Three short-term H

2CO flares (∆t<3 months) have

been observed to date via systematic Arecibo monitoring. The flare amplitudes appear to be linearly decreasing. The outbursts appear periodic (P ~ 8 months) The next flare is predicted to occur in Apr 08, and will be looked for.The H

2CO flares are time-correlated with 6.67-GHz

CH3OH flares. Most of the CH3OH frequency

components show flares that are delayed by a month, but one is prompt. High resolution follow-up with the EVLA and MERLIN is planned to investigate the phenomenon in detail.

Araya, Hofner, Linz, Kurtz & Creech-Eakman

AUSAC Meeting · March 17-18, 2008

Line detections in IC 860: (Top) HCN v2=1, J=4 and excited-OH (4660 MHz) absorption lines: (Bottom) H2CO and CH2NH emission lines,

Pre-biotic Molecules and Other Lines in ULIRGs(a) Arp 220 (b) Other ULIRGs

v2=1 direct l-type absorption lines of HCN (J = 4, 5 and 6. An excitation temperature of ~120-150 K is implied. Non-detection of the J=2 level is likely to be due is to free-free absorption in the foreground ionized ISM.

Emission from the 110–111 methanimine (CH2NH) multiplet, (the 6 transitions shown by vertical lines.) This is likely to represent weak maser emission.

Latest News: Detection of v2=1, J=3, HCN in Arp 220 (2645 MHz) gives a line-center optical depth, ~ 3 at 1630 MHz.

IC 860

H109α recombination line in NGC 3628

(ULIRG = Ultra-Luminous Infra-Red Galaxy)

AUSAC Meeting · March 17-18, 2008

Future Option: Single-Pixel “pdev/edev”

Note: All but X-band would use an instantaneous bandwidth of 1 GHz, which is presently available.

The anticipated “single-pixel” mode of operation for the new “pdev/edev” spectrometers offers exciting possibilities for, e.g. broad-band (bandwidths up to 2 GHz) pulsar observing, and line searches in Galactic and extragalactic targets. Reasonable parameters for a Galactic spectral scan, (velocity resolution ~ 0.5 kms-1), could be: