HERSCHEL/SPIRE

les programmes extragalactiques

-SAG2: Galaxies proches, échantillon de référence

-SAG1: Sondages profonds

V. Buat pour les SAG 1 & 2

SPIRE/HERSCHEL

SAG 2: LOW-Z EXTRAGALACTIC ASTRONOMYTHE HERSCHEL GALAXY REFERENCE

SAMPLE

Alessandro Boselli, Steve Eales,Veronique Buat, Jonathan Davies, Kate Isaak, Walter K Gear, Matt Griffin, Marc Sauvage, Laurent Vigroux, Suzanne Madden, Koryo Okumura, David Elbaz, Pierre Chanial, George Bendo, Dave Clements, Mattia Vaccari, Frederic Galliano, Jammie Bock, Seb Oliver, Matt Page, Ismael Perez Fournon, Eli Dwek, Bernhard Schulz, Luigi Spinoglio, Jason Stevens, Maarten Baes, Werner Zeilinger, Christine Wilson

SPIRE/HERSCHELTHE HERSCHEL GALAXY REFERENCE SAMPLE

Aim of the project: to study the dust content and distribution of “normal” galaxies

1) Dust plays a principal role in the physics of the ISM and in the process of SF in galaxies : HI ->H2; shields the gas from the ISRF (UV radiation); cooling of the gas; produced and injected in the ISM by massive stars2) Major ingredient in the determination of the extinction - energetic balance (important for measuring SFR)3) Pollution of the intergalactic medium in clusters4) Reference sample for high z studies

Why SPIRE?: the pick of the dust

emission in “normal” galaxies

is ~ 200 µm

IRAS, ISO, Spitzer, ASTRO-F < 200 µm

Boselli et al 2003

Why SPIRE?: although not

important energetically, cold dust is dominant

in mass

Cold dust difficult to observe with

SCUBA in “normal” galaxies Boselli et al 2003

SPIRE/HERSCHEL The Herschel galaxy reference survey

A representative sample of ~300 galaxies in the nearby universe

-distance range 15<dist<25 Mpc (to have a volume limited sample)

- high galactic latitude (to avoid cirrus contamination) |b|>54 °

-pointed observations of few tens of minutes per galaxy at 250, 360 & 520 µm

SPIRE/HERSCHEL The Herschel galaxy reference survey:

the sample

-2MASS K selected sources (to have a luminosity/mass selection)1) K < 9 mag: E + S0 + Spirals 2) 9 < K< 12 mag: to add late type systems with a large range of

luminosity and morphological type

E+S0: down to 11 mJy -> 104 Msun( dust)Spirals: down to 22 mJy -> to detect dust in the outer disk, from standard gas to dust ratios

313 selected galaxies, to be observed in 100 h

The whole sample:

K< 9 mag: 126 objetcs

9 < K< 12 mag 187 galaxies

The cluster sub-sample (Virgo & Fornax)K< 9 mag 36 galaxies

9 < K< 12 mag 40 galaxies

SPIRE/HERSCHEL The Herschel galaxy reference survey:

main objectives

•For galaxies of different type and luminosity:-Dust properties (mass, temperature, gas to dust ratio,..) -The role of dust in the physics of ISM (relation with SFR) -Spectral Energy Distribution •Effects of the environment on dust properties of nearby galaxies (clusters vs. field)• Intergalactic dust cycle•Dust properties in ellipticals :merger history (dusty disks) and origin of dust in ellipticals•Local dust-mass function

SPIRE/HERSCHEL The Herschel galaxy reference survey:

corollary data

•Large surveys available or under way-UV from GALEX (1500-2300 A)-Visible from SDSS (u, g, r, I, z)- NIR from 2MASS (J, H, K)-radio continuum NVSS/FIRST (20 cm)-R~1000 integrated spectroscopy (Balmer decrement, metallicity…) with CARELEC at the OHP - Halpha imaging (SFR) with 2.1m telescope in San Pedro Martir (Mexico- Mid- and Far-IR (<200 mic) from ASTRO-F- HI from HIPASS & ALFALFA-Westerbok/VLA HI : for ellipticals-CO survey of all galaxies without CO measurements(JCMT & FCRAO)-850 microns with SCUBA2-Xrays from Chandra/XMM

SPIRE High-z

A wedding cake of blank field surveys

P.I. Seb Oliver

Resource by Institute

67 Individuals with average effort of 0.25 fte per year

La participation française revue et corrigée…

Resources by Country

Key science

• How and when galaxies form

• Search for unknown populations of high z IR galaxies

• AGN versus SB, AGN fraction

• Star formation rates

Summary of the GI proposal

• 850 h awarded to the high-z team on SPIRE• Observations of blank fields and clusters

with SPIRE & PACS- 650 h for PACS• A single large project: A bolometric exploration of the star

formation history of the Universe as a function of the environment

--> 1500 hours on Herschel (SPIRE+PACS)

Why Herschel for the high z?

• The emission of galaxies and of the cosmic background peaks around 60-200 microns --> SCUBA or SPITZER do not probe the bulk of the emission

• The aim of the proposal is to measure the bolometric IR emission of galaxies over a large

range of z.

Areas, Depths, Fields

The wedding cake

Clusters-lensingGOODs-S- 0.04deg2 4

mJy @ 350µmGOODS-N- 0.04 deg2 8

mJy @ 350 µmGOODS-Groth Strip-Lockman0.75 deg 2 13 mJy @ 350 µmCOSMOS-XMM- 4 deg2 26

mJy @ 350 µmXMM-Lockman-CDFS- 10 deg2 29

mJy @ 350 µmSWIRE- 50 deg2- 74

mJy @ 350 µm

L(bol)-z plane sampled by the surveys

Confusion limits (at 5)

• 250 microns: 20 mJy, FWHM= 17 arcsec, 1800 sources/sq.deg

• 350 microns: 19 mJy, FWHM= 24 arcsec, 945 sources/sq.deg

• 500 microns: 19 mJy, FWHM= 35 arcsec, 420 sources/sq.deg

Observations of clusters

• z=0.2 to > 1• Using gravitational lensing to go below the

confusion limit• 50% of the unresolved background might be

identified with specific galaxies (against 10% without lensing)

• 15 (?) clusters to be observed• Modelling in progress based on the SPIZER

analyses of Dole et al. 2006

Science Goals

•Key Science Goals–Agreed before hand

–Coordinated by individual or small team–Distributed effort through workflows

–Specific Papers identified

•Secondary Science Goals–Less “managed”–Open process

•Schedule tied to data release cycle

Data Products• Primary Data Products

– SPIRE Points Source Catalogues (P1)– SPIRE Maps (P2/P3)– PACS Point Source Catalogues (P1)– PACS Maps (P2/3)

• Secondary Data Products (best efforts)– SPIRE/PACS band-merge (P2/P3)– X-ID lists (P3)

• Key Complementary/Follow-up Data– Various….(P3)

• Secondary Complementary/Follow-up Data (Not released)

Time-table (Launch to DR1)

Perhaps too tight

Data, Valid. Sci.

Merci pour votre attention

Prédictions des modèles(Lagache, Puget & Dole)

15 mJy @ 350 mu

(100 deg2)

100 mJy (400 deg2)

Number counts

Redshift distributions

CIB analysis

• Confusion will prevent the detection of individual sources at high z

• Stacking technique based on a priori information from PACS and/or SPITZER

• Fluctuations analysis

Data processing and releases

• Phase 0: checking that the science goals will be achieved, optimization of the tools

• Phase 1: quickly after the end of the observations (…). For the best observations, reduction and release to the Herschel community. SPG pipeline used. Optimized tools validated and released to the Herschel community

• Phase 2: main stage. All the data are processed with optimized pipelines, band-merging, multi-wavelength catalogs. Specific analyses: extended sources, diffuse emission, P(D). Released to the Herschel community

• Phase 3: final archiving, follow-up data combined. First scientific papers.