SED measurements of radio galaxies 1 < z < 5
description
Transcript of SED measurements of radio galaxies 1 < z < 5
![Page 1: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/1.jpg)
SED measurements of radio galaxies
1 < z < 5Bob Fosbury (ST-ECF) on behalf of the
SHzRGS team
Daniel Stern - PI, Peter Eisenhardt (JPL)Carlos De Breuck - Co-PI, Joel Vernet, Alessandro Rettura (ESO)
Bob Fosbury (ST-ECF)Andrew Zirm (STSCI)
Brigitte Rocca-Volmerange (IAP)Nick Seymour, Mark Lacy, Harry Teplitz (SSC)
Arjun Dey, Mark Dickinson (NOAO)Wil van Breugel, Adam Stanford (UCLLNL)George Miley, Huub Rottgering (Leiden)
Partick McCarthy (OCIW)Dave Alexander (IoA)
![Page 2: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/2.jpg)
Objective
The hosts of powerful radio galaxies represent the most massive galaxies at their epoch
By observing the SED through the restframe H-band with Spitzer, we measure the stellar masses
The Spitzer images allow us to investigate the (proto)-cluster environment
The SMBH is characterised from X-ray and radio measurements
![Page 3: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/3.jpg)
Evidence
gE and cD galaxies in the local universe
r^(1/4) light profiles in distant sources (NICMOS)
HzRG reside in (proto-)cluster environments
Large, luminous Ly-a halos
sub-mm detections => high star formation rates
NIR Hubble diagram (K-z; Rocca-Volmerange et al. 2004)
Correlation of stellar bulge and BH masses
![Page 4: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/4.jpg)
Sample
The objective is to cover the radio luminosity - redshift plane as uniformly as possible in the range 1 < z < 4, covering two orders of magnitude in radio luminosity
Sample chosen to maximise number of supporting observation (but no bias towards cold dust properties - 850micron Obs not Det)
Solid symbols - HzRGs in our Spitzer sample with IRAC/IRS imagingLarge circles - MIPS observations as wellFilled circles - HzRGs with HST dataFilled squares - HzRGs with SCUBA dataPlusses - parent sample of 225 HzRGs from which our sample of 70 was drawn
![Page 5: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/5.jpg)
Spitzer observations
3-camera programme: GO 3329 (Stern)
IRAC: 4x30s in all 4 bands => 5-sigma at m_AB=22 for ch 1 & 2 and at m_AB=20 for ch 3 & 4
IRS: 16 micron imaging (peak-up) mode; 2x60s => 5_sigma at 0.17mJy
MIPS: subset of 21 sources with low 24 micron background; all three bands [24 (30s), 70 (30s), 160 (50s)] but most detections at 24
![Page 6: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/6.jpg)
Supporting observations
48/70 have HST imaging; total exposure of 1.5Ms
16 have Chandra/XMM-Newton data
43 have published sub-mm data
22 have deep optical polarimetric observations from Keck/VLT
Use to construct broadband SED and characterise AGN and dust re-radiation in addition to the evolved stellar population
Also use to study galaxy morphology and environment
![Page 7: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/7.jpg)
WFPC2 - IRAC
HST/WFPC2 [top] and Spitzer/IRAC [bottom] images of 5 HzRGs
From left to right, galaxies shown are 3C266 (z = 1.275), MRC 0152-209 (z = 1.920), USS 1707+105 (z = 2.349), MRC 0406-244 (z = 2.427), and 4C+41.17 (z = 3792)
Images are 30 arcsec on a side, oriented with North up and East to the left. Note that a number of the fields show overdensities of infrared-bright, optically-faint galaxies
![Page 8: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/8.jpg)
Supporting proposals
ESO and Palomar imaging (for 4000Å-break)
IRS mid-IR spectroscopy (Silicate, PAH and continuum)
MIPS - to extend subset
ESO imaging polarimetry (removal of AGN component)
MAMBO and SCUBA sub-mm
VLA 4.8 and 8.4 GHz to extend 3 GHz restframe depth: polarimetry to measure RM environment
HST archive
![Page 9: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/9.jpg)
4C+23.56
This is our initial example object with very complete observational coverage.
![Page 10: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/10.jpg)
Keck spectropolarimetry
Showing the dominance of the scattered quasar in the restframe ultraviolet(Cimatti et al. 1998;Vernet et al. 2001)
![Page 11: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/11.jpg)
Composite SED
![Page 12: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/12.jpg)
SED modelling
Initial modelling with stellar population (PEGASE.2), hot and cold dust (Siebenmorgen), and synchrotron components
Will add the scattered AGN
We need deeper sum-mm observations for most of this sample
![Page 13: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/13.jpg)
Restframe H-band estimates
By Nick Seymour (elliptical templates +warm dust)
Full SED fitting tbd by Alessandro Rettura
![Page 14: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/14.jpg)
Restframe H-band vs. z
Derived from best-fit models to the multi-band photometry
Sources with large error bars lack MIPS 24micron observations, making the decomposition of stellar and dust/AGN components of the SED less secure.
The error bars for these sources show that the range of reasonable stellar luminosities given (1) the total H-band luminosity and (2) that the stellar emission typically dominates at observed 3.6micron (as seen in the modelling of sources with MIPS data) and hence can predict a reasonable lower value to the H-band luminosity.
The red line shows the expected H-band luminosity of a passively evolving 10^12M_sun elliptical galaxy from the PEGASE.2 models (see Rocca-Volmerange et al., 2004)
![Page 15: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/15.jpg)
First cut at M-z for Radio Galaxy hosts
![Page 16: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/16.jpg)
BH mass vs. stellar mass
Local galaxies with measured kinematic and stellar masses (blue stars)
HzRG with measured X-ray luminosities (red squares)
Implications for BH growth at early epochs
![Page 17: SED measurements of radio galaxies 1 < z < 5](https://reader035.fdocuments.in/reader035/viewer/2022062409/568147fa550346895db52eff/html5/thumbnails/17.jpg)
Nick Seymour’s status pages