Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.mrao.cam.ac.uk/secure/amiday/talks/radio_counts.pdf Дата изменения: Wed Oct 5 02:00:35 2011 Дата индексирования: Fri Feb 28 14:57:03 2014 Кодировка: Поисковые слова: закон вина

Radio source counts (from some CMB experiments)

Jo Dunkley
Oxford Astrophysics

AMI day, Sept 30 2011


Detections with AMI ­ 15 GHz
1900 sources, 27 sq degrees, to 1 mJy

Davies et al 2010


ACT southern field at 150 GHz
1

2

3

4 Region mapped 4x with ј of data:


Detections in ACT/SPT­ 150 GHz
ACT: 157 sources in 455 sq degrees 15-1500 mJy (5 sigma) 98% known radio sources SPT: 141 sources in 90 sq degrees to 4mJy,Vieira et al 2010

Marriage et al 2010


Planck collab, 2011

­Detec%on level in ERCSC: at 2040 GHz WMAP is more sensi%ve, then Planck `wins' at 70100 GHz. ­Planck src numbers from 30143 GHz: |705, 452, 599, 1381, 1764|


Counts at 15 GHz from AMI

Daviesetal,2010:deZo2modelover/underpredicts.


Counts at 150 GHz from ACT/SPT

Marriage et al 2010


Adding in Planck

Planck collab, 2011


Spectral index: separating radio/IR

Planck collab, 2011


Spectral index

Planck collab, 2011

Marriage et al 2010: Flat spectrum synchrotron sources with evidence for steepening at high frequencies. Same in Planck. AMIat15GHz:esCmatesshallowerspectrumforlowfluxsources



Planck radio results:
1.
· · ·

Statistical properties of radio sources (Toffolatti/GonzalezNuevo, 13)
Low freq detections match WMAP. New look at 100-217 GHz counts (about 500 non-IR src). Extends ACT/SPT counts to higher flux. Are consistent; de-Zotti model overpredicts bright sources. Steepening of index above 70 GHz. Clear bimodal distrib in 143-217 for radio/IR indices.

2.
·

New extreme sources (Partridge, 14)
Steepening consistent with optically thin synchrotron at high freq.

3.
· ·

SEDs of northern sources (Lahteenmaki, 15)
Full-range SEDs of 104 Northern radio sources, mapping synchrotron and inverse Compton bumps. Flatter sources than expected - accelerated electron energy spectrum could be harder than thought: s=1.5 instead of 2.5 for the synchrotron


SZ cluster contamination?
· 3 ACT sources are BCG of low-z x-ray clusters, also in AT20G · Only 1 ACT cluster has bright source in same region and may be projection effect · Src contamination is more of an issue for unresolved contributions