ISM/Star Formation (8)

Probing CH and CH+ in the diffuse interstellar medium using concerted SPIRE / HIFI observations

Proposal ID: GT1_aabergel_4

Principal Investigator: Alain Abergel

Time: 2.0 hours

Category: Interstellar Medium/HII regions


This proposal is presented by the SPIRE SAG4 consortium associated with HIFI experts for a specific follow-up of two SPIRE FTS recently observed sources map for the HII compact sources G29.96-0.02 and G32.80+0.19. Naylor et al. (2010) report the detection of the fundamental rotational transition of CH+, in absorption against the compact source continuum, due to its presence in the the diffuse interstellar medium. These detections are important to shed light on the formation processes and on the occurence of CH+, which are still outstanding questions in astrophysics. For a better understanding of CH+ associated diffuse medium chemistry and to effectively be able to spectrally resolve the components along the line of sight, a follow-up with a good signal-to-noise (above 30) with HIFI is mandatory. We need the HIFI capabilities to separate CH+ emission and absorption, to derive the kinematics of the absorptions, to assign them to individual interstellar components, and to extract relevant column densities by properly taking into account saturation effects. We wish to sample two galactic lines of sights using the two compact sources as background, to complement SPIRE FTS observations already performed. These two sources offer not only a scientific goal to follow CH and CH+ in the diffuse medium but also a unique opportunity to cross calibrate the SPIRE FTS and HIFI Herschel instruments with a moderate amount of integration time. In this proposal, we ask for 2 hours of total integration time.

Completing the OH ladder for HH 46

Proposal ID: GT1_abenz_1

Principal Investigator: Arnold Benz

Time: 3.4 hours

Category: Star Formation/Young Stellar Objects


First results from PACS observations towards the low-mass protostar HH 46 show surprisingly bright OH lines. The hydroxyl radical OH plays important roles in the water and oxygen chemistry of star-forming regions and their cooling. Furthermore, the hydroxyl-to-water line ratios are interesting tracers for ionizing radiation. We propose a nearly complete observation of the OH ladder in low-mass star formation for the first time. Four OH transitions in the class I object HH 46 were detected by PACS. We propose complementary observations towards the source in PACS line spectroscopy mode at 53, 56, 65, 71, 96, 115 and 135 micron. We gain insight in the origin and formation of OH from the PACS spatial information. The completeness of the OH ladder allows a reliable determination of the OH abundance and thus constrains water chemistry and cooling contribution more precisely. In addition, we propose HIFI observations of the OH transition at 163.4 micron to resolve the three hyperfine components for the first time. This will allow to determine optical depths of OH and test the hypothesis of asymmetries between the two closely spaced triplets, as the second triplet will be observed within the HIFI priority science program. Note: This proposal is submitted under the Swiss part of the HIFI guaranteed time program; HIFI PI: Frank Helmich, HIFI Swiss Lead CoI: Arnold O. Benz

SPIRE-FTS observations of Young Stellar Objects revealed by SPIRE and PACS images in star forming regions

Proposal ID: GT1_azavagno_1

Principal Investigator: Annie Zavagno

Time: 8.7 hours

Category: Star Formation/Young Stellar Objects


We propose to use the SPIRE-FTS to obtain the spectrum of a 14 young stellar objects that have been observed with PACS and SPIRE in imaging. These YSOs are highly embedded sources that have not been observed before at wavelengths shorter than 100 micron. We propose to use the FTS to ascertain their physical properties (mass and age) using chemical tracers such as the ones that trace outflows and shocks. These YSOs span a large range of luminosity, evolutionary stage and mass. The obtained FTS spectra will constitute the first existing far IR spectral database of YSOs.

Heating and cooling mechanics in massive star formation

Proposal ID: GT1_cdedes_1

Principal Investigator: Carolin Dedes

Time: 3.2 hours

Category: Star Formation/Young Stellar Objects


Massive stars are important constituents of the interstellar medium (ISM) in our Galaxy and beyond. Their strong feedback processes influence the dynamics, energetics and chemistry of the surrounding interstellar medium both locally and on large scales. An important question to be answered is the one of cooling and heating mechanisms in regions of massive star formation. In the vicinity of massive stars, heating is provided mostly by far-UV (FUV) and infra-red radiation. Cooling is mostly provided by emission in the fine structure lines of CII. There are however other atomic and molecular lines such as OI, CO, OH and H$_2$O which can become significant coolants in the dense, embedded regions of massive star formation. This early phase when the forming massive star is still deeply embedded in its natal envelope, yet already interacting with, and potentially destroying, its environment through copious amounts of UV radiation, massive outflows and ultra compact HII (UCHII) regions, is an important phase in the star formation process. To understand the heating and cooling balance in this phase, one has to consider the contributions of various radiative and dynamical processes such as the FUV radiation from the young star itself, shocks created by strong stellar winds and the photon dominated regions (PDRs) where the radiation impinges on the molecular material. The tracers of these processes can be observed in the far-infrared, a wavelength range that is now accessible at unprecedented high spectral and spatial resolution with the Herschel Space Observatory. We propose to observe the aformentioned tracers of cooling and heating in the massive star forming region IRAS 12326-6245 to obtain a complete picture of the different processes, the regions they originate from and how they interact. This proposal is for time granted to the HIFI hardware team (PI: Frank Helmich) and to be accounted as part of the Swiss guaranteed time (Lead-Co-I: Arnold O. Benz).

SPECHIS: SPIRE Spectral Line Surveys of HIFI-GT-KP Sources

Proposal ID: GT1_epoleham_1

Principal Investigator: Edward Polehampton

Time: 7.0 hours

Category: Interstellar Medium/HII regions


We propose to obtain several SPIRE submm line surveys of the most significant star forming regions at the highest spectral resolution allowed by the SPIRE-FTS. A list of 27 sources currently being observed by us with HIFI and PACS in five different Guaranteed Programs is proposed. As a result of these complementary data, the most relevant sources in the galactic center (Sgr B2, Sgr A...) and galaxy disc (Orion, W49N...) would be observed with the 3 spectrometers on board Herschel, and analyzed and interpreted by the same teams. A unique spectral data set of these sources will thus be available for the general community with a great lasting value.

SPIRE spectroscopy of protoplanetary disks

Proposal ID: GT1_golofs01_4

Principal Investigator: Goran Olofsson

Time: 14.9 hours

Category: Circumstellar/Debris disks


We propose spectroscopy of Herbig Ae/Be and T Tauri stars using the SPIRE FTS. This instrument covers a broad spectral range, 200 - 650 µm, which is basically unexplored with the exception of two atmospheric windows at 350 and 450 µm. The FTS is well suited for both the definition of broad features as well as the detection of emission lines. Our source list is co-ordinated with the OT Key program DIGIT (PI: N. Evans) together providing spectra in the range 50-650 microns. It includes 10 Herbig Ae/Be stars and three T Tauri stars. The ages of the stars range from 1 Myr to 10 Myr, the mass range is 1-5 Msun and the temperature range is 4300-10000 K. The flux density of the continuum varies from a few Janskys to tenths of Janskys between the sources and in general the brightness for a given source decreases rapidly from the short wave- length to the long wavelength end. As our main purpose is detecting emission lines and as these are known (from other spectral regions) to correlate poorly with the dust emission (but rather with other properties as disk flaring and accretion rate) we propose a standard observation time of one hour per source, except for the fainter T Tauri stars which are observed a bit longer. We expect to detect lines from CO,13CO, H2O, CI and possibly SiO, HDO and NH3. The relative brightness distribution for the carbon monoxide lines and in particular the 13CO/12CO ratios for the J=4-3 to J=13-12 transitions, covered by the FTS, will provide powerful constraints on the density and temperature structure of the disk. Water vapour lines will provide further constraints on the density and radiation field in the regions inside the "snow line"

Tracing the evolution of the interstellar medium from molecular clouds to stars

Proposal ID: GT1_mpestalo_4

Principal Investigator: Michele Pestalozzi

Time: 14.0 hours

Category: Interstellar Medium/HII regions


The aim of the present proposal is to detect and understand how the interstellar medium (ISM) changes due to star formation. To do this we intend to perform a (large scale) spectral survey using the SPIRE spectrometer. The main idea is to scan with the SPIRE FTS along gradients of increasing temperature, density and star formation activity, e.g. from the edge of a star forming region to its centre. Making sure to include regions of different levels of star formation activity and clump/core density, we aim to probe the ISM in its different phases and see what are the relevant changes in its physical properties. Starting from the assumption that all stars in a star formation region are formed from the same material but not at the same time, we wish to probe the physical conditions of the ISM from a low-activity region to a region where stars are already formed. In this way we will be able to directly relate the changes in the ISM to star formation activity.

Anatomy of Class 0 Protostellar Envelopes in their far-IR Spectrum

Proposal ID: GT1_rvavrek_1

Principal Investigator: Roland Vavrek

Time: 28.0 hours

Category: Star Formation/Young Stellar Objects


During the Science Demonstration Phase, Herschel's instrumentation has proven its outstanding capabilities to provide an unprecedented view of far-infrered spectra at the 50-670 microns regime. We propose a program to obtain spectra with the PACS Intergral Field- and SPIRE FTS Spectrometers of luminous and nearby (d<400 pc) low-mass protostellar envelopes previously categorized as Class 0 sources. Our sample includes well studied sources which can be considered as templates of this early evolutionary stage of protostars. This selection of densely clustered, double and relatively well separated individual protostars consists the largest Herschel sample for which spectra will be taken in entire wavelength range. PACS detections of water, OH and [OI] lines will be used to determine the fundamental properties (such as density, temperature, infall rate, and molecular abundance and accretion rate) of the interacting components of a protostellar system: the infalling envelopes, disks and outflows. SPIRE data is expected to reveal lower state water lines and help to derive the gas temperature and density via the CO intermediate-level rotational lines. We aim to provide a valuable spectral reference database for better understanding and testing the theory of the earliest phases of star formation and we can examine the role of interaction between protostars in dense groups and multiple systems.

Solar system (2)

Herschel In-situ Asteroid & Comet Observation programme

Proposal ID: GT1_lorourke_9

Principal Investigator: Laurence O'Rourke

Time: 20.3 hours

Category: Asteroids


In September 2010, 25 years will have passed since the first in-situ encounter of a space probe with a comet. This first visit occurred in September 1985 when the International Cometary Explorer (ICE), passed through the tail of P/Giacobini-Zinner. Up to that point, comet and asteroid scientific observations were always based upon remote sensing be they performed from ground or from space. The next opportunity for a comet encounter arose with the return of Halley's Comet in 1986, whereby many satellites (Giotto, Vega 1 & 2, Suisei & Sakigake) were launched to perform in-situ observations. The first asteroid flybys, Gaspra & Ida/Dactyl, occurred as part of Galileo's journey to Jupiter. Since this time, NEAR, DS1, Hayabusa, Rosetta, Deep Impact, Stardust-NExT and Dawn satellites have all been launched with the aim of performing flybys, orbiting & sample return. Remote sensing & in-situ measurements are considered highly complementary in nature: remote sensing shows the global picture, but conversion of measured fluxes in physical quantities frequently depends on poorly constrained model parameters (e.g. dust size distribution or fluorescence efficiencies). In-situ techniques measure physical quantities in a more direct way, but are limited in spatial coverage. The benefit of both combined is that we can compare surface composition, reflectance, albedos & temperatures of in-situ and remote sensing and as a result greatly improve the scientific understanding of the objects in question. This proposal focuses on using the Herschel Space Observatory to remotely observe a select set of in-situ comets/asteroids. The down-selection from 29 asteroids & comets to the final eight was made based upon many criteria, the main one being prioritisation of the most important open scientific issues existing for each of the targets for which the Herschel Space Observatory, its sensitivity & wavelength coverage, could indeed contribute in a highly significant and, in specific cases, conclusive way to their resolution.

A last chance to measure the size of the nucleus of Comet Hale-Bopp directly in the IR

Proposal ID: GT1_mkidger_2

Principal Investigator: Mark Kidger

Time: 10.7 hours

Category: Comets


Comet C/1995 O1 (Hale-Bopp) was one of the three intrinsically brightest comets of the last 600 years. It is generally agreed to be a giant object with a nucleus of diameter in the range 40-80km compared to the 15x8km of 1P/Halley. It is also one of the most intensively studied objects in history and the only giant comet ever to be studied intensively with modern detectors. The large flux, long lead time to perihelion and exceptional period of visibility (19 months with the naked eye and, so far, at least 17 years telescopically) have contributed to an unprecedented degree of knowledge and understanding of this comet. The fact that the comet was known to be active at 13AU pre-perihelion (and possibly even at 17AU) and that it has been active a well past 20AU post-perihelion has demonstrated its extraordinary duration of activity. In June 2010 Hale-Bopp will pass the orbit of Neptune and now finally appears to be inactive. This will allow us to attack the problem of the one great unknown about the comet: the size of the nucleus. Dozens of size estimates have been published, ranging from under 15km to 250km, but it is generally acknowledged that radio techniques have underestimated the size, whereas infrared techniques and PSF fitting have tended to overestimate it. Given that the rotation period, rotation mode and pole orientation are well-determined, an accurate value for the diameter of the nucleus will allow dynamical information on the mass and even the internal structure of the nucleus to be determined. We propose to observe Hale-Bopp in PACS blue+red using the technique of background subtraction to obtain 4-sigma at 1mJy, equivalent to detecting a nucleus of diameter around 40km. We request that these observations be scheduled in the optimum window in June 2010 to subtract out the confusion noise. Combining PACS with visible data, we will obtain, at worst, a strong model-constraining upper limit to the nucleus diameter and albedo that should stand for 2500 years.

Stars (10)

Mapping the distribution of the crystalline silicate forsterite in the Cat's Eye Nebula (NGC6543)

Proposal ID: GT1_bdevries_1

Principal Investigator: Ben de Vries

Time: 3.9 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


We propose to observe a 5x5 oversampled map wavelength centered on the 69micron band of crystalline silicate forsterite for the Planetary Nebula NGC6543. This will be the first time that we can resolve the location of crystalline dust in a mass-loss outflow. This will help is investigate the dust-formation in the circumstellar environment of an evolved star and look at the link with mass-loss and possibly binarity. The total observing time is 3.87h

The rich mineralogy of the post Asymptotic Giant Branch star MWC922.

Proposal ID: GT1_bdevries_2

Principal Investigator: Ben de Vries

Time: 1.0 hour

Category: Evolved Stars/Planetary Nebulae/Supernovae


We propose to observe a full SED of the post Asymptotic Giant Branch star (post-AGB) MWC922. ISO spectra have already shown that this object has a very rich mineralogy. With a full spectral scan we want to get a complete inventory of the solid state bands in this object. MWC922 is one of the few sources that shows a narrow band at 65 micron that can be assigned to enstatite, and as such could serve as an important template to establish the signature of cold enstatite in circumstellar environments. MWC922 also shows a broad band centered around 65 micron, whose nature is under discussion but could be diopside. This could offer the rare occasion where cold diopside could be studied. Solid state bands in the spectrum will be identified using laboratory data available in the literature and we will establish relative abundances of the materials. Furthermore, the presence of the narrow 65 micron enstatite band can be verified and we can search for other enstatite bands in the 65-75 micron wavelength range (clino and ortho enstatite).

SUCCESS: A SUbmm Catalogue of Circumstellar Envelopes of StarS with Herschel/HIFI

Proposal ID: GT1_dteyssie_1

Principal Investigator: David Teyssier

Time: 35 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


We propose to perform a biased survey of Circumstellar Envelopes (CSE) in AGB and post-AGB stars in order to build a reference catalogue in two to three sub-millimetre and FIR CO transitions. The proposed observations will provide access to the emission of the envelope gas layers in the temperature range ~100 to 2000K. These warm layers are fundamental to the field of stellar evolution because they are the regions where the acceleration of the gas takes place, and therefore where the envelopes are being formed. Because of the significant atmospheric opacity affecting ground-based observations at the corresponding wavelengths, this warm gas could never be probed in a systematic manner over large source samples. In fact, in some of the transitions emitting in this temperature regime, no observation at all is possible from the ground. The catalogue we are proposing to build will collect the emission of two CO transitions (J=5-4 and J=9-8) probing different layers of the warm gas in about 74 sources, and measure a high-J CO transition (J=14-13) in the 10 most intense sources of the sample. The total time to build this data-set is 35 hours. When eventually combined to the smaller sample collected by the GTKP HIFISTARS, this will form an unprecedented catalogue of over 100 AGB and post-AGB stars in two to three fundamental CO lines of the sub-millimetre and FIR domain, and offer a legacy data-base for the modelling of the shaping parameters of evolved stars.

Forsterite dust in the circumstellar environment of evolved stars

Proposal ID: GT1_jblommae_1

Principal Investigator: Joris Blommaert

Time: 10.6 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


PACS range spectroscopy will be performed around the 69 micron forsterite dust feature of evolved stars. With the spectral resolution and sensitivity of PACS we will be able to fit the profile of the forsterite feature which is very sensitive to temperature. By studying the forsterite feature in a wide range of evolved stars and from different populations (including Galactic Bulge and LMC) we want to determine the role of forsterite in the dust formation in the circumstellar environments.

A molecular line survey of IRC+10216

Proposal ID: GT1_jcernich_4

Principal Investigator: Jose Cernicharo

Time: 45.0 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


We would like to perform a systematic line survey of the prototype carbon-rich AGB star IRC+10216. This object is particularly rich in carbon chain molecules and radicals and shows an impressive HCN spectrum in the submillimeter and far-infrared domains. The coverage of the HIFI instrument will permit to characterize the complete molecular content of the innermost zones of the envelope and complement the low frequency observations available from ground-based radio observatories. The sensitivity of the survey is such that at 1 THz we approach the detection limit of a ground based telescope such as the 30m IRAM radiotelescope after several hours of observing time. The 1500 GHz we want to cover requires 45 hours of GT observing time. A line survey covering 100 GHz with the 30m IRAM radiotelescope at an equivalent sensitivity requires several weeks of observing time.

V838 Mon: aftermath of a stellar merger

Proposal ID: GT1_kexter_1

Principal Investigator: Katrina Exter

Time: 7.3 hours

Category: Circumstellar/Debris disks


V838 Mon is one of the most enigmatic objects observed in stellar astrophysics in recent decades. It came to attention when it underwent a powerful eruptive outburst in Jan. 2002, increasing in luminosity by a factor of 100 over a period of 3 months. Immediately following this event a spectacular light echo was formed from the outburst light reflecting off the surrounding dust. Hubble Space Telescope images following this expanding light echo have brought V838 Mon to public attention. What makes V838 Mon an unusual star is that the outburst is not of any type heretofore seen; the scenarios of a nova-like event or thermonuclear runaway have been discounted, on the basis of the stellar type and outburst details. The theories that best explain the outburst are a giant star engulfing a planetary system or, more likely, a merger between a very low mass star and a very young, maybe pre-main sequence low-intermediate mass star. Observations show that the envelope of the star expanded in response to the stellar impact, and than it may now be beginning to contract. Many O-bearing molecules, dust, an SiO maser and possibly a jet have been observed from the star. If the outburst was indeed caused by the merging of two stars, this is an extremely rare event. Herschel observations of this star will allow us to model the kinematics, chemistry, temperature and density structure of the stellar photosphere and the cool envelope surrounding the star. These will help answer questions still remaining about the stellar impact, and will also allow us to understand more about how a star responds to such a violent event.

A sensitive search for light hydrides towards IRC +10216

Proposal ID: GT1_magundez_1

Principal Investigator: Marcelino Agundez

Time: 15.0 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


Among the molecular species typically observed in the interstellar and circumstellar medium, light hydrides have been traditionally elusive to detection since their rotational spectrum lies in the submillimeter and infra-red ranges of the electromagnetic spectrum, which is very difficult to observe from ground due to severe atmospheric absorption. This project aims at utilizing the remarkable capabilities of the HIFI instrument on board the Herschel Space Observatory to perform a sensitive search for several light hydrides toward the circumstellar envelope of the carbon-rich evolved star IRC +10216, which is one of the richest molecular sources in the sky, with more than 70 molecules observed to date.

Structure and Evolution of Disks Around Brown Dwarfs and Very Low Mass Stars

Proposal ID: GT1_pharve01_2

Principal Investigator: Paul Harvey

Time: 46.0 hours

Category: Brown Dwarfs/Very Low-Mass Stars


We propose a program of deep PACS photometry of 50 young brown dwarfs and YSOs at the hydrogen-burning limit, 0.08 solar masses. We have selected these from documented BDs in the literature that have been observed to have circumstellar disks based on their 1-24um SEDs. None of these objects is bright enough to have been detectable with Spitzer beyond 24um. We eliminated objects from our list that are likely to be detected in the large-area Herschel Key Project surveys of star-forming regions, and we also eliminated objects whose disks are likely to be below our detection limit of a few mJy at 70um. We expect to be able to detect or obtain important upper limits on the cold disk emission at 70um for all 50 sources, and to obtain useful detections or limits at 160um for at least a third of our objects. We will combine our results with those from Spitzer and ground-based telescopes and then model the SEDs with two different radiative transfer codes existing at the University of Kiel and University of Grenoble. These results will provide the first quantitative assessment of the structure and mass of cold dust around the lowest mass objects that form like stars. Our data and modeling will provide important new constraints to the understanding of disk evolution and planet formation by extending the range of central object masses to ~ 0.01 solar masses.

Unveiling the evolutionary paths of the most massive stars

Proposal ID: GT1_proyer_1

Principal Investigator: Pierre Royer

Time: 2.1 hours

Category: Evolved Stars/Planetary Nebulae/Supernovae


Several important questions remain open regarding the latest stages of evolution of the most massive stars, in particular regarding the exact evolutionary paths taken between the various subtypes of O stars, LBVs and Wolf-Rayet stars, and the mass-loss history of these objects throughout their lives. In this proposal we will address these questions by extending the massive stars programme of the the MESS GTKP. In the MESS programme, we focus on the LBV phenomenon. Here we will focus on the properties of nebular ejecta from a peculiar O-type star and a Wolf-Rayet star. These together will allow us to study the relationship between these three types of related, massive, mass-losing stars, in particular to better understand how the mass loss both changes with evolutionary stage and how it may dictate the evolutionary paths taken.

Tracing Remnant Gas in Planet Forming Debris Disk Systems

Proposal ID: GT1_vgeers_1

Principal Investigator: Vincent Geers

Time: 2.5 hours

Category: Circumstellar/Debris disks


Recent studies of gas emission lines with Spitzer and sub-millimeter telescopes have shown that 10-100 Myr old stars with debris disks have too little gas left to form Jupiter like gas giant planets. Whether enough gas remains in these systems to form ice giant planets is still unanswered. The [OI] emission line at 63 micron is one of the most sensitive tracers of gas mass in the ice-giant region of 10-50 AU in disks, and Herschel PACS is therefore uniquely suited to trace the remnant gas in planet-forming disks. We propose to obtain PACS line spectroscopy of [OI] (63 micron) for two nearby young stars, HR 8799 and HD 15115, which are two systems with detected giant planets or signs of planet formation, while still harbouring prominent debris disks that could be in the process of forming ice giants such as Neptune and Uranus. The proposed observations will probe down to gas masses of 0.01 Earth masses, and allow us to constrain prospects for ice giant formation, measure gas-to-dust ratios in evolved disks to compare with planet formation / disk evolution models, and put constraints on whether the dust dynamics in these systems is driven by the remnant gas or by the radiation. Note: this proposal is submitted under the Swiss part of the HIFI Guaranteed Time program; HIFI PI: Frank Helmich, HIFI Swiss Lead CoI: Arnold Benz.

Galaxies/AGNs (8)

[CII] , [OI] and far infrared continuum emission properties of local Lyman Break Analogs

Proposal ID: GT1_aconturs_1

Principal Investigator: Alessandra Contursi

Time: 24.8 hours

Category: Low-z galaxies


[CII] , [OI] and far infrared continuum emission properties of local Lyman Break Analogs We propose to observe 9 Ultra Compact UV-luminous galaxies, selected from Overzier et al (2009) with the PACS spectrometer in the [CII] and [OI] lines at 158 micron and 63 micron, and with the PACS photometer in the green and red filters. These galaxies are at redshifts ~0.2-0.3, they are rare in the nearby Universe and they were chosen because they are analogs of the Lyman Break Galaxies (LBGs), (Heckman et al 2005). For this reason, they have been called: "Local Break Analogs" (LBAs). LBAs and LBGs share many global properties such as, stellar mass, metallicity, dust extinction, star sormation rate (SFR), physical size and gas velocity dispersion. Despite they have been observed with SPITZER at 24 and 70 micron, no systematic and detailed studies of their infrared properties has been done so far. We want to characterize the far infrared (FIR) properties of these galaxies. The porposed [CII] and [OI] observations together with ancillary CO data will allow us to study the physics of the ISM and its interplay with the heating sources. Given the similarity between LBAs and LBGs, these results will shed light also for the LBGs population, helping their further characterization. We will also verify if LBAs, and by analogy also LBGs, are [CII] deficient or not. In the case LBAs are not [CII] deficient, we will empirically calibrate the [CII] emission as a SFR indicator. The SFR will be calculated from the FIR emission measured with PACS, assuming that in such UV bright sources most of the FIR is produced by young stars. Thus, this data set will provide an unique local reference sample for the future infared observations of high redshift UV-bright galaxies with ALMA.

Herschel Exploitation of Local Galaxy Andromeda

Proposal ID: GT1_jfritz_1

Principal Investigator: Jacopo Fritz

Time: 18.2 hours

Category: Local Group galaxies


We propose to observe Andromeda on a 5.5x2.5 degree field, an area which will be ~4.5 larger with respect to any previous IR observations, with SPIRE and PACS fast scan Parallel Mode, thus obtaining the most complete FIR survey of this galaxy both in terms of spatial mapping and spectral coverage. Sampling the whole galaxy will allow us to get a complete statistical sample of the cloud masses, temperatures, luminosities, as well as sampling the total dust in M31 right out to the most cool extended regions, and the total energy balance. Our observation strategy, covering such a large field, will enable us to trace the presence of both warm and cold dust much further away than was ever done before. Exploiting ancillary data at both millimeter and radio wavelengths, particularly of the HI emission, it will be possible to have a complete map describing the coupling of dust -at all temperatures- and gas down to Andromeda's outskirts in both the diffuse medium and in the outer parts of its spiral structures. We will study the characteristics of the radiation field, derive gas-to-dust ratios as a function of the distance from the galaxy's bulge, study the mechanisms that are responsible for the dust ejection and detect, for the first time, cold dust in the galaxy's outskirts.

Bright Seyfert Nuclei: FTS spectroscopy

Proposal ID: GT1_lspinogl_2

Principal Investigator: Luigi Spinoglio

Time: 17.8 hours

Category: Active galaxies/ULGs/QSOs


This proposal is to measure the full 200-670um FTS spectra at high resolution (~500 km/s) of 10 bright Seyfert nuclei. We are aiming to detect the high-J CO lines, the [CI] and [NII] fine structure lines and any other possible emission or absorption from H2O or other molecules. The selected targets include four AGN1's (two Seyfert 1's and two HBLR-Seyfert 2's), three AGN2's and three lower nuclear activity objects. These objects have been chosen because they are the brightest at 60-100 um and their IR luminosity has been separated between AGN and Starburst components through mid-IR spectroscopy. This program is fully complementary to the Hercules OTKP, which is focused on SPIRE FTS spectroscopy of the ULIRG/LIRG population, while the present proposal targets optically bright nuclei, at a presumably later evolutionary stage. We expect that the detection of the CO ladder in Seyfert nuclei will allow us to measure the effects of the AGN on the circum-nuclear ISM of the galaxy through detection of X-ray dominated regions. Moreover the molecular spectroscopy could reveal the presence of the predicted molecular tori. The 10 galaxies for which we request SPIRE FTS observations of their nuclei in one single position can be observed in a total integration time of 14.7 hours. To complement the spectroscopic observations, photometric imaging with SPIRE and PACS is also requested with a total time needed of 0.7 and 2.4 hours, respectively.

Bright Seyfert nuclei: PACS spectroscopy

Proposal ID: GT1_lspinogl_4

Principal Investigator: Luigi Spinoglio

Time: 14.0 hours

Category: Active galaxies/ULGs/QSOs


This proposal is to obtain PACS spectroscopy of 10 bright Seyfert nuclei to observe the 6 ionic fine-structure lines, four high-J CO lines and three OH doublets. The selected targets include four AGN1's (two Seyfert 1's and two HBLR-Seyfert 2's), three AGN2's and three lower activity objects. These objects have been chosen because they are the brightest at 60-100 micron, their luminosity has been separated between AGN and Starburst components through mid-IR spectroscopy. The immediate goals are to obtain a large set of FIR tracers to be able to classify and model the various levels of non-thermal and starburst activity in local Seyferts, using both atomic (Herschel and Spitzer) and molecular (Herschel and H2 from Spitzer) transitions. The mid-to far-IR classification of activity in galaxies will be essential in the close future to interpret the spectroscopic surveys at long wavelength that will be performed by Herschel, ALMA and SPICA. The range spectroscopy with PACS has been optimized to allow detection of 4 CO lines, 3 OH doublets and 6 fine structure lines in a total time of 14.0 hours.

HERschel Observations of Edge-on Spirals (HEROES)

Proposal ID: GT1_mbaes_1

Principal Investigator: Maarten Baes

Time: 6.0 hours

Category: Nearby galaxies


We propose to use PACS and SPIRE to map the dust distribution in a sample of seven large edge-on spiral galaxies with regular dust lanes. We will look for the presence of cold dust at large galactocentric radii and investigate the link between dust, gas and metallicity as a function of radius. We will also constrain the vertical distribution of the dust and particularly look for dust emission at large heights above the plane of the galaxies. We will compare the observed Herschel maps with simulated maps resulting from detailed radiative transfer models based on optical and near-infrared images. This will enable us to investigate whether we can confirm the existence of a dust energy balance problem suggested by previous observations (the dust seen in absorption in optical maps underestimates the dust seen in emission) and investigate possible ways to alleviate this potential problem.

Herschel imaging photometry of nearby Seyfert galaxies: testing the co-existence of AGN and starburst activity and the nature of the dusty torus.

Proposal ID: GT1_msanchez_2

Principal Investigator: Miguel Sanchez Portal

Time: 15.1 hours

Category: Active galaxies/ULGs/QSOs


We propose to perform 6-band PACS & SPIRE imaging photometry of a sample of nearby Seyfert 1.x and 2 galaxies in order to characterise the physical nature of their infrared emission by means of a multi-component SED fitting (AGN, starburst and host galaxy), combining existing ground- and space-based data from UV to MIR with Herschel FIR observations. Active galactic nucleus (AGN) and starburst activities, being among the most energetic extragalactic processes, have been studied separately until the past decade, when evidence that the two phenomena are related and, most frequently, coexistent started to accumulate. The FIR peak of cold dust emission constitute a powerful tracer of star formation. However, the study of such an important feature in the innermost regions of nearby AGN hosts has been, until the advent of Herschel, seriously limited by the low spatial resolution and limited spectral coverage of the existing facilities. These new data, given the unprecedented angular resolution and spectral coverage of the Herschel Space Observatory will overcome this limitation, allowing us to probe the cold and very cold dust components across the galaxy and even in the nuclear and circum-nuclear regions. In addition, it will allow us to unveil the nature of the dusty torus (e.g. clumpy vs. smooth, flared disc), breaking model degeneracies.

Peering into the Dust: The Far-IR Emission in M31 at GMC-Resolution

Proposal ID: GT1_okrause_4

Principal Investigator: Oliver Krause

Time: 24.4 hours

Category: Local Group galaxies


We propose to image M31 (3x1deg) with PACS and SPIRE in slow parallel mode to understand the dust heating processes and efficiencies in normal spiral galaxies. Our observations will provide a unique deep and panchromatic 70,100,160, 250, 350 and 500 micron view of the inner stellar disk of M31 at the highest possible spatial resolution with Herschel. Combined with Spitzer 8 and 24 micron data, this imaging will provide a detailed map of the thermal-IR SED at a resolution unparalleled for any other large galaxy. The 6-18 arcsec spatial resolution of Herschel at 70-250 micron corresponds to 20-60 pc at the distance of M31 and matches the scales of molecular clouds complexes (GMCs; ~ 40 pc) as well as of HII regions and clusters thereof (about 10-50 pc). Existing GALEX and optical data, as well as upcoming 900 orbit HST imaging will provide us with an unprecedented, resolved picture of all stellar populations younger than ~200 Myrs, which should encompass much of the relevant dust heating sources at scales of a few to a few 10 parsecs. With such information on both the thermal state of the dust and on the heating sources in hand, our SED modelling can then be used to understand over what length scales and with what efficiency stars heat the dust. The results will also serve as a local high resolution calibration of Herschel data on more distant galaxies such as from the KINGFISH OT key project. This proposal is part of a coordinated effort to image M31 and its surroundings: Here we aim on sensitive 70-250 micron coverage at the highest spatial resolution for the bright inner stellar disk while the diffuse outer cold dust envelope including the companion NGC205 are the target of a second proposal by Fritz et al. For the analysis of extended very cold dust emission, the SPIRE data will be provided collaboratively to the other team.

The Herschel Legacy of distant radio-loud AGN

Proposal ID: GT1_pbarthel_1

Principal Investigator: Peter Barthel

Time: 38.0 hours

Category: Active galaxies/ULGs/QSOs


We propose Herschel observations of the virtually complete sample of 3CR radio-galaxies and quasars in the redshift range 1 < z < 2.5, and a representative additional set of 4C objects extending to redshift z = 3, in order to quantify the orientation-dependence of AGN radiation (AGN unification), to investigate the interplay between accretion onto the central black-hole and star-formation in the hosts, to understand the evolution of the black-hole/stellar-bulge relation, and to make the first accurate assay of the energetics of AGN at the epoch of their peak activity, the quasar era. The low-frequency radio-selection provides us with very powerful and massive active galaxies free from any orientation/obscuration bias, a requirement for testing AGN unification. The properties of particularly the high-z 3CR sources are well known throughout the electromagnetic spectrum, except in the rest-frame mid- and far-IR, where they were hitherto outside the reach of space missions. We propose PACS/SPIRE 70-500 micron photometry of 71 3CR+4C sources in 5 bands, in order to measure their detailed spectral energy distributions between available Spitzer and SCUBA/MAMBO data. The rest-frame FIR emission serves as an isotropic calorimeter and the MIR/FIR luminosity ratio is determined by the relative strength of the AGN and star-forming contributions combined with dust obscuration. These observations will return crucial new information on the energy processes in powerful AGN and their hosts at the cosmic heyday, providing an essential anchor for studies of galaxy and AGN evolution.

Cosmology (5)

The star formation history of galaxy clusters

Proposal ID: GT1_baltieri_3

Principal Investigator: Bruno Altieri

Time: 48.4 hours

Category: Galaxy clusters/Lensing clusters


We propose to study the star formation history of galaxy clusters in the -yet unexplored- redshift range of0.9-2.4, at a time galaxy clusters were assembling galaxies and local massive early-type galaxies were building up, with deep PACS and SPIRE imaging on a sample of 8 high-redshift galaxy clusters and proto-clusters. We will be in a position to confirm the increase in the fraction of dusty star-forming cluster galaxies found by Spitzer up to z=0.8 (the mid-IR Butcher-Oemler effect) and extend it to z>1 for the first time, at wavelength close to the peak of the spectral energy distribution of star-forming galaxies. Our sample includes clusters at different mass/richness This will allow to understand the role and importance of environment and the physical processes by which galaxy clusters are accreting new galaxy falling from the outskirts with high star formation rates. This program promises to shed some new light too on the assembly of the oldest galaxies at z=0 by combining the clean and robust Herschel-derived SFRs (no assumptions of SEDs) and a sample of clusters that covers a broad range in mass, age and dynamical state at previously unexplored redshifts for these wavelengths.

SEDs and energetics of lensed UV-bright high redshift galaxies

Proposal ID: GT1_dlutz_4

Principal Investigator: Dieter Lutz

Time: 41.0 hours

Category: High-z galaxies


Optically selected rest-frame UV-bright galaxies are a key component of the z~1.5-3 high redshift galaxy population. No understanding of the evolution of cosmic star formation or mass assembly can be obtained without them. Initial Herschel results find a discrepancy between their total infrared luminosity as estimated by extrapolation from the mid-IR and the directly measured rest-frame far-infrared, suggesting changed SEDs compared to local objects of similar luminosity. Because high fidelity individual Herschel SEDs cannot be obtained for the typical UV-bright galaxy from blank field surveys, we here describe a project to obtain full PACS/SPIRE SEDs for a sample of 16 strongly lensed UV-bright objects, found behind massive lensing clusters as well as behind individual lensing SDSS galaxies.

Deep SPIRE FTS follow-up of H-ATLAS lensed sub-mm galaxies

Proposal ID: GT1_ivaltcha_1

Principal Investigator: Ivan Valtchanov

Time: 12.0 hours

Category: High-z galaxies


One of the major discoveries in the IR and sub-mm wavelengths are the so-called sub-mm galaxies (SMGs). These high-redshift, optically obscured, star-forming galaxies account for more than half of the far-infrared background and their star-formation rates are orders of magnitudes higher than most galaxies in the local Universe. SMGs are considered the precursors of today's most massive elliptical or bulge galaxies and are amongst the most difficult obstacles for models of galaxy formation and evolution. They may provide clues for understanding the formation and evolution of galaxies in the very early Universe - one of the most challenging and important topics in astrophysics. Wide area surveys, like the Herschel Astrophysical Teraherz Large Area Survey (H-ATLAS) - the largest Herschel Open Time Key Programme, will detect a significant number of SMGs at z>2. We propose SPIRE Fourier-Transform Spectrometer (FTS) follow-up of the first two H-ATLAS SMG identified during the Herschel Science Demonstration Phase. Both targets HATLAS 81 and HATLAS 130 are lensed by foreground galaxies and are already subject to ground-based and HST follow-up observation. Radio-mm observations at CSO/Zspec and GBT/Zpectrometer secured their spectroscopic redshifts at 3.04 and 2.625 respectively, based on CO lines. The proposed SPIRE FTS observations will result in the deepest spectra of SMGs in 197-670 microns band (corresponding to ~50-170 microns rest-frame), achieving line sensitivity of 10^{-17} W/m2 (5-sigma) and continuum at signal-to-noise greater than 4. This will enable us to constrain the physical conditions of the ISM using a combination of the the atomic cooling lines, the total IR luminosity, and the CO spectral-line energy distribution obtained from radio-mm ground-based observations. In order to better constrain the blue wing of the SED peak we also add short PACS mini-maps around each source, going down to 10 and 15 mJy (5-sigma) at 100 and 160 microns.

A direct probe into the Epoch of Reionisation: Herschel’s first look at a high z GRB host, the case for GRB 050904.

Proposal ID: GT1_jmcastro_1

Principal Investigator: Jose Maria Castro Ceron

Time: 12:0 hours

Category: High-z galaxies


The reionisation of the universe between redshifts 6 and 30 is the one fundamental astrophysical event since the Big Bang. The role of galaxies in this process is still not properly understood. Several star forming galaxies at z ~ 6 have been identified in recent deep, narrow field surveys, but the expensive observations along with cosmic variance and contamination make it difficult to assess their contribution to reionisation, or to significantly increase the sample. By virtue of being extremely luminous end states in the evolution of massive stars, gamma ray bursts (GRBs) are a critically important tracer of star formation out to the highest redshifts. It has now been demonstrated that GRBs exist at z>6, and there are already published HST and Spitzer observations of the host galaxy of GRB050904 at z=6.3. Spectroscopic confirmation, including detailed information on the host ISM, is available for this burst. Here we propose to observe the host galaxy of GRB 050904 with Herschel PACS and SPIRE to very deep limits. We aim to extend our knowledge of this galaxy to the far-infrared and submillimetre wavelengths. This will allow us to build realistic models, since those windows are unexplored to date, and to describe the physical properties of a high z GRB host galaxy, thus directly probing reionisation and the role high z galaxies in the process. Further we will test whether the M − Z and L − Z relations evolve beyond the current redshift limits.

The Spectrum of IRAS 08339+6517 and its Physical Implications

Proposal ID: GT1_mharwit_2

Principal Investigator: Martin Harwit

Time: 2.4 hours

Category: High-z galaxies


The Spectrum of IRAS 08339+6517 and its Physical Implications IRAS 08339+6517 is a highly compact starburst galaxy, whose remarkable nature was first recognized at optical wavelengths by Margon et al., in 1988 [1]. They noted its strong, narrow emission lines in H$\alpha$, H$\beta$, [OIII], [OII], [OI], [NII], [SII] and [CIV], and found it position to coincide with that of a previously-unidentified IRAS source, whose flux at 60 and 100$\mu$m, respectively was 5.9 and 6.5 Jy. The X-ray luminosity of the source is $\sim 1.0\times 10^{41}$ erg s$^{-1}$, suggesting that it may be a hybrid AGN /starburst. Currently no far-infrared spectrum of this highly interesting nearby source exists, presumably because prior to Herschel no telescope was sufficiently powerful to provide a spectrum. The aim of this proposal is two-fold: (i) to obtain an analysis of the physical conditions --- temperature and density --- in the atomic and ionic and molecular constituents of this galaxy's gaseous phases; the abundance of their primary elements O, C, and N; while also probing the far-infrared dust continuum and dust contents of the galaxy at longer wavelengths than IRAS provided; and (ii) to forge, as further explained, an intermediate chemical and thermodynamic link between galaxies in the nearby and distant universe.