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Clusters of galaxies and

future studies with SRT

Luigina FerettiINAF Istituto di Radioastronomia

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1. Radio sources in Clusters of galaxies

2. Status of the Sardinia Radio Telescope

3. Science with the SRT

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phenomenology related to the evolutionary status of the cluster

MACSJ0717+3745

Ma et al. 2008,2009

1. Radio sources in Clusters of galaxies

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Lewis et al 2003

A2029

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merging relaxed: cool core

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Diffuse Radio Sources in clusters :

1 - radio halos

2 – radio relics

3 – mini-halos at the center of cooling core clusters

4 – radio galaxies related to cD galaxies in cool core clusters, radio bubbles, ghost bubbles

5 - central relics

all steep spectrum sources

MERGER

RELAXED

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most distant & most powerful radio halo

z= 0.55, P1.4 GHz~1.6 1026 W/Hz

(Bonafe

de e

t al

2009)

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A2345

Bonafede et al. 2009

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Diffuse Radio Sources in clusters :

1 - radio halos

2 – radio relics

3 – mini-halos at the center of cooling core clusters

4 – radio galaxies related to cD galaxies in cool core clusters, radio bubbles, ghost bubbles

5 - central relics

all steep spectrum sources

MERGER

RELAXED

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(X-ray: Forman et al. 2007)

See : Mathews and Brighenti 2008

M 87 (Radio: Owen at el. 2000)

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Perseus – Fabian et al 2000 Chandra (Böhringer et al ROSAT)

Minihalo = 350 kpc(Sijbring & De Bruyn 1993)

X-ray

Radio + X-ray

Radio

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Hydra A – X-ray ChandraMc Namara et al. 2000

Radio : Taylor et al. (VLA)

Most radio sources in cavities are FRI

13Gitti Feretti Schindler 2006

RBS 797

Color: X-ray Contours:Radio

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The interaction between the AGN jets and the

ICM is believed to be the primary feedback

mechanism between the BH and its environment

one strong or several small episodes of energy release

radio bubbles

confinement

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interaction between CR and ICM: THE CRs AFFECT THE ICM

- Cavities are filled with cosmic rays which inflate

the cavities and form a much larger lobe

- Bubbles can rise to the cluster outskirts

- Eventually the cosmic rays diffuse away from the

cavities, impact with/ leak into the surrounding medium

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Link between radio and X-ray emission

Understand the energetics and the dynamical evolution

of plasma bubbles inflated by radio jets in the hot cluster atmosphere radio spectra correlations CR/gas interaction confinement energy budget lifetimes/duty cycles

FUTURE PROSPECTS

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2. Status of the Sardinia Radio Telescope

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The Radiotelescope-Diameter: 64 m

-Frequency range :

300 MHz – 100 GHz

-Actively controlled surface :

1008 panels

1116 mechanical actuators

- Multiple focal positions

P, G, BWG

- Frequency agility

- State-of-art receivers (multi-beam)

- Digital back-ends

- Fiber optic connection

-Transmitting capability

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Quality of the site: Low rain Low atm opacity Low RFI Low wind

S. Basilio

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Observing time (in %) with an expected atmospheric opacity τ<0.1 23.8 GHz 31.4 GHz 100 GHz (Ambrosini et al.)

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Digital Spectrometer

Pulsars

1 GHz BW, 1024 channels

Spectrometer

60 MHz BW

Dual Band

Total Power Analogic Back-end

7x2 outputs, 2 GHz BW

RECEIVERS

310-420 MHz 1.3-1.8 GHz Primary focus

5.7-7.7 GHz Mono-feed BWG focus

18-26 GHz Multi-feed 7 pixels Gregorian focus

BACK-ENDS

First light: 4 BANDs

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13 September 2009

First light of SRT: 2010

http://www.srt.inat.it/webcam

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3. Science with the SRT

In collaboration with Isabella Prandoni SRT Project Scientist

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Radio Astronomy Science

●VLBI – eVLBI : x2 sensitivity ≤ 22 GHz x5 > 22 GHz mm-VLBI 43 GHz (7 mm) [VSOP2]

86 GHz (3 mm) [GMVA /ALMA]

● Italian VLBI

● Single dish

Space Science (20%)● Data down link● Space science : Radio science, Deep Space Network

1.4 GHz

5 GHz

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Medicina•

Noto•

Cagliari•

Italian context

64 m

32 m

32 m

•Matera

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18-22 GHz Multifeed

•Surveys

•H2O Megamasers

•Extragalactic CO

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18-26 GHz

Multi-feed

- Pulsars:

- Search for Recycled/msec pulsars in the

Galactic Center binary systems

msec pulsar/BH gravitazional tests

- Continuum Surveys :

- Map of free-free emission on the Galactic Plane

Ultra-Compact HII Regions

- Deep Fields [SRT confusion limit: 50-70 Jy (rms)] information @ 10 GHz high z AGN/low luminosity

- Line Surveys :

- Search for H2O masers in the Local Group

Distance and 3D motions Dark matter

Cosmology

- Unbiased Mapping NH3 in the Galactic Plane Star forming regions, T of Molecular clouds, Prestellar cores, Gas and dust properties

Surveys Surveys

2 deg

0.5

deg

Centro Galattico

Courtesy A. Possenti

Courtesy J. Brand

Lagoon Nebula

Z = 6

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CO(1-0)

Cold component of molecular gas in high-z galaxies

EXTRA-GALACTIC COEXTRA-GALACTIC CO

Weiss et al. 2005

GBT/Effelsberg: 20hr on sourceLarge BW (1-2 GHz), Tsys 20-25 KFuture:90–115 GHz

70-90 GHz

35-50 GHz

26-36 GHz

Redshift Machines:

eg 14 GHz BW

@ 26-40 GHz

redshifted CO 1<z<7 JJ-1 J4

CO(4-3)

CO(3-2)

CO(2-1)

CO(1-0)

CO(1-0) K band @ 3.5<z<5.5

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Observational Policy

Open sky Fraction reserved to KSP (possibly larger in early SRT operations)

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Thank you