FIR & Sub-mm Astronomy comes of age Herschel Space Observatory Observing Opportunities

AstroPizza16 Jan 2008

HerschelMattia Vaccari

FIR & Sub-mm Astronomy comes of age

Herschel Space Observatory

Observing Opportunities

Mattia Vaccari - University of PadovaAlberto Franceschini & Giulia Rodighiero

Thanks also to Carol, Jim, Matt, Michael, Seb & all the

ISOCAM, ELAIS, SHADES, SWIRE, SPIRE & SCUBA2 folks



UV/Opt/NIR FIR/Sub-mm

Sky

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W/m

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1 10 100 1000

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Wavelength [m]

The FIR & Sub-mm Universe



The effects of dust extinction andthe degeneracy of optical observables

Degeneracy is old-fashioned

Time for panchromatic SEDs

Sanders & Mirabel 1996

Lagache et al 2005



The integrated background light in the far-infrared and sub-millimeter region of the spectrum is approximately equal to the integrated background light in the optical and UV part of the

spectrum. To develop a complete understanding of galaxy formation, this background light must be resolved into galaxies and their physical properties must be characterized.

The Cosmic Infrared BackgroundResolved Into Discrete Sources



PWV = 1.0 mmPWV = 0.5 mmPWV = 0.2 mmPWV = 0.1 mm

PWV ~ Chajnantor 30%

PWV ~ Dome C 30%

Minier et al 2007

Into Thin Air : FIR & Sub-mm Atmospheric Transmission vs Precipitable Water Vapor

Lower atmospheric transmission is generally coupled with higher (sky &

instrumental) background and temporal variability



Herschel is an ESA cornerstone mission– spacecraft, launch (scheduled for 31 Oct 2008) and operations provided by ESA – instruments ‘nationally’ funded with international collaborators

Herschel is the first space facility to completely cover this part of the far infrared and submillimeter (60 - 670 m) range– large (3.5 m) aperture, low emissivity (~5%), passively cooled (70-90 K) telescope– cryogenically cooled focal plane science instruments with >3 years lifetime– total absence of atmospheric absorption and emission– full spectral access with low and stable background

Herschel has unique and complementary characteristics– first 4-m class space telescope ever, has much larger aperture than missions with

cryogenically cooled telescopes (IRAS, ISO, Spitzer, Akari,…)– larger & colder aperture, better ‘site’, and more observing time than balloon- and

air-born instruments (~1000 SOFIA flights per year)– larger field of view than interferometers

PACS - PI : Albrecht Poglitsch, MPE, Garching, Germany– imaging photometry and spectroscopy over 57-210 m

SPIRE - PI : Matt Griffin, Univerity of Wales, Cardiff, London, United Kingdom– imaging photometry and spectroscopy over 200-670 m

HIFI - PI : Thijs de Graauw, SRON, Groningen, The Netherlands– very high resolution spectroscopy over 480-1250 and 1410-1910 GHz (157-625 m)

The Herschel Mission



The Actual Spacecraft

Launch : 31 Oct 2008



Study the formation and evolution of galaxies in the early universe– how and when did galaxies form?– is there an unknown population of high-z IR galaxies?– star formation rates? bolometric luminosities? – Starburst vs AGN fraction?– ‘connect’ near-IR and sub-mm galaxies

Study the formation of stars and physics of the interstellar medium– how do stars form out of the interstellar medium?– circulation/enrichment of the interstellar medium - astrochemistry– detailed studies of nearby (resolvable) galaxies - templates

Study cometary, planetary, and satellite atmospheres– history of the solar system– pristine material in comets– important water lines

Herschel Main Science ObjectivesThe Young & Cold & Dusty Universe



PACS



• 3-band Imaging Photometer

- 250, 360, 520 m (simultaneous)

- ~ 3

- 4 x 8 arcmin field of view

- Diffraction limited beams(17, 24, 35”)

• Imaging Fourier Transform Spectrometer

- 200 - 670 m (complete range covered simultaneously)

- 2.6 arcmin field of view

- = 0.04 cm-1 ( ~ 20 - 1000 at 250 m)

SPIRE Observing Capabilities



SPIRE Detector Arrays

200 – 325 m37 detectors

315 – 670 m 19 detectors

Spectrometer

8 ar

cmin

Photometer500 m

43 detectors350 m

88 detectors

4 arcmin

Sets of detectors with exactly overlapping beams on the sky

250 m139 detectors

Beam FWHM



Herschel AO Schedule (31 Oct 2008 Launch)

Overall (3-yr Baseline Mission) Observing Time Breakdown : ~ 1000 days ~ 20000 hrsGuaranteed Time (GT) = 32% & Open Time (OT) = 68%

GT = 30% each to 3 PIs, 7% to HSC, 3% divided between 5 Mission Scientists

Commissioning, Performance Verification & Science Demonstration L - L+6m Routine Science Operations L+6m - L+42

m

GT & OT Key Projects AO Issue 01 Feb 2007 GT Key Projects Proposal AO Deadline 05 Apr 2007 (~ 5000 hr) GT Key Projects Results Announcement 05 Jul 2007 OT Key Projects Proposal AO Deadline 25 Oct 2007 (~ 5500 hr) OT Key Projects Results Announcement 28 Feb 2008 GT & OT Cycle 1 Projects AO Issue 28 Feb 2008 GT Cycle 1 Projects Proposal AO Deadline 03 Apr 2008 (~ 1000 hr) GT Cycle 1 Projects Results Announcement 05 Jun 2008 OT Cycle 1 Projects AO Deadline Late 2008 (~ 5000 hr) GT & OT Cycle 2 Projects AO Deadline Late 2009 (~ 500 hr + 3000 hr) Extra Time (0.5 yr “expected” extended mission) Later (~ 3000 hr)



University– Alberto Franceschini : SPIRE Co-I– Giulia Rodighiero : PACS High-z Science Consortium Member– Mattia Vaccari : SPIRE Associate Scientist & ICC Scientist– Gabriele Mainetti : newly hired PhD student

Observatory– Gianfranco De Zotti : SPIRE Consultant– Pasquale Panuzzo (2003-2006) : SPIRE ICC Scientist

Main focus is on high-z galaxy studies through a coordinated program of PACS GT (PEP) and SPIRE GT (HERMES) surveys and on the PACS & SPIRE Instrument Control Centers (ICCs)

PEP + HERMES ~ 1500 hr and arguably the largest single space astronomy project ever (at a very reasonable 50,000 Euros/hr)

Padova Involvement



Where do we go from here?

Herschel will launch on 31 Oct 2008 but in the meantime– EARA Herschel WorkShop (18-19 Feb @ IAP)

– ASI/INAF Herschel Open Time WorkShop (10-12 Mar @ ASI)

– Open Time AO Issue & Deadline expected in March & Late 2008

Look up info & watch out for updates at http://herschel.esac.esa.int

Note that SCUBA2@JCMT (450/850 m) and AZTEC@LMT (1.1 mm) are also coming online sometime over the next year or so

Well, looking forward to launch…

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FIR & Sub-mm Astronomy comes of age Herschel Space Observatory Observing Opportunities