Large Programs [2008-2012]

The Pan-Andromeda Archaeological Survey (PandAS)

PI: McConnachie

Instrument: MegaPrime. 226 hours, spread over B semesters

100% Validated

The Lambda-Cold Dark Matter hierarchical paradigm is robust to large scale observables, and it is on galactic scales that our understanding of the cosmological evolution of matter is most incomplete. Many of the predicted features of galaxies, such as faint satellites and diffuse stellar haloes, are extremely low surface brightness (> 31 mags per sq.arcsec ). The Milky Way, M31 and M33 are therefore the only three large galaxies in the Universe which can currently provide robust tests of, and constraints on, many fundamental predictions of galaxy formation models. We propose the Pan-Andromeda Archaeological Survey (PAndAS), which will obtain g and i imaging of over 300 sq.degrees of the M31/M33 sub-group. PAndAS will provide the first panoramic view of galaxy haloes over a volume of ~15 million cubic kpcs, and will be complete to 32 - 33mags per sq. arcsec. PAndAS will provide the deepest and most complete panorama of galaxy haloes available, and will be used to compare to and constrain cosmological models of galaxy formation over an order of magnitude in halo mass. It will be unrivaled by any other extra-galactic wide field survey and will become a benchmark study of near field galaxy formation. The legacy value of PAndAS - for M31, M33, the Local Group, dwarf galaxies, globular clusters, stellar populations, galaxy formation and MW structure - is immense. It will become the primary reference dataset for all subsequent studies of the stellar populations of these galaxies, and will remain so into the era of Thirty Meter Telescopes and beyond. This survey is only possible for the M31/M33 sub-group, and it is only possible using the unique capabilities of CFHT/MegaPrime.

The Next Generation Virgo Cluster Survey (NGVS)

PI: Ferrarese

Instrument: MegaPrime. 771 hours, spread mainly over A semesters

77% Validated

The Virgo Cluster is the dominant mass concentration in the local universe and the largest collection of galaxies within ~35 Mpc. As the most thoroughly studied cluster in the universe, it is the target of many ongoing and planned surveys at X-ray, UV, IR, submm and radio wavelengths. However, the best existing optical survey of the Virgo Cluster — the photographic Virgo Cluster Catalog of Binggeli et al. (1985) — is now nearly a quarter century old and hopelessly out of date by modern standards. We propose to capitalize on the wide-field imaging capabilities of MegaPrime to carry out the Next Generation Virgo Cluster Survey: a programme to survey the cluster from its core to virial radius, in u*g r i z , to a point-source depth of g ~25.7 mag and a corresponding surface brightness of g ~ 27.7 mag arcsec-2. The NGVS will completely supersede all existing optical studies of this uniquely important system, and, by leveraging the vast amount of data at other wavelengths, will allow us to address a wide range of fundamental astrophysical questions, including: the faint-end shape of the luminosity function, the characterization of galaxy scaling relations over a factor 107 in mass, the cluster/intracluster medium/galaxy connection, and the fossil record of star formation and chemical enrichment at z~0. Numerous ancillary projects — from a survey of the Galactic halo to cosmic shear measurements — will also be enabled. The NGVS will be a lasting legacy of CFHT: not only will it be the definitive study of baryonic substructures in a low-z cluster environment, but it will yield the benchmark observational database against which the next generation of hierarchical formation models will be tested.

Magnetic Protostars and Planets (MaPP)

PI: Donati

Instrument: ESPaDOnS. 690 hours, spread over A and B semesters.

79% Validated

MaPP on the web is here

MaPP aims at studying the impact of magnetic fields on the physics of protostars and accretion discs, and thus on the formation of stars and planetary systems. Youth is indeed the period in the life of non-degenerate stars at which magnetic fields play a key role, through the accretion/ejection processes involved in the collapse of the protostellar cloud. In particular, our study will focus on the core regions of protostellar accretion discs, the newly born star and their potential close-in giant planets. We propose to carry-out the first spectropolarimetric survey on a significant sample of low-mass protostars, including a few bright protostellar accretion discs; From this survey, we will study the large-scale magnetic field topologies of protostellar objects using tomographic imaging techniques. By comparing these results to the predictions of new theoretical models and MHD simulations, MaPP will answer several major open questions on star formation and produce updated models incorporating the effect of magnetic fields. MaPP is part of the international MagIcS initiative; all data collected with MaPP will thus directly feed the MagIcS LEGACY database.

Magnetism in Massive Stars (MiMeS)

PI: Wade

Instrument: ESPaDOnS. 640 hours, spread over 9 semesters.

93% Validated

Massive stars are those with initial masses on the main sequence above about 8 solar masses, leading to core-collapse (or pair-instability) supernovae. They dominate the ecology of the Universe as "cosmic engines" via their extreme output in radiation and particles - not only as supernovae, but also during their
entire lifetimes - with far-reaching consequences. Although the existence of magnetic fields in massive stars is no longer in question, our knowledge of the basic statistical properties of massive star magnetic fields is seriously incomplete. There is a troubling deficit in our knowledge of the scope of the influence of fields on massive star evolution, and almost no empirical basis for how fields modify mass loss. This proposal represents a consensus effort by an international team of recognized researchers who have compiled a strategic sample of sources to address these outstanding issues. The basic aim of this Large Program is to exploit the unique characteristics of ESPaDOnS obtain critical missing information about the poorly-studied magnetic properties of these important stars, to confront current models and to guide theory. The general scientific objectives are: 1. To identify and model the physical processes responsible for the generation of magnetic fields in massive stars; 2. To observe and model the detailed interaction between magnetic fields and massive star winds; 3. To investigate the role of the magnetic field in modifying the rotational evolution of massive stars; 4. To investigate the impact of magnetic fields on massive star evolution, and the evolution of the fields themselves. In particular we will explore the connection between magnetic fields of nondegenerate massive stars and those of neutron stars, with consequential constraints on stellar evolution, supernova astrophysics and gamma-ray bursts.

CFHQSIR: Searching z - 7 quasars with WIRCam in the CFHT-LS Wide fields

PI: Cuby & Willott

Instrument: WIRCam. 160 hours over [2010B-2012B]

100% Validated

CFHTQSIR on the web is here

Information on the progress of the observations at CFHT is here

We propose to search for z - 7 quasars with WIRCam in the CFHT-LS Wide fields. High redshift quasars are invaluable tools to investigate the Intergalactic Medium (IGM) into the epoch of re-ionization, its ionization state and metal enrichment level. High-z quasars are also interesting to investigate their chemical properties, the growth of black holes early in the Universe, and the evolution of primo rdial objects. By observing - 130 sq. degrees in two epoch observations in the Y band, we expect to detect [3-4] quasars (average) in the redshift range [6.5 - 7.5]. We will identify targets from their detection in the Y-band images that are undetected in any of the deep optical images of the field. This is a straightforward extension of the technique that has been used to search for z - 6 quasars in the SDSS and CFHQS. Serious candidates will be followe d up as part of this programme in the Y, J and Ks band to get higher SIN and near-IR colours. The optical -near-IR colours of high-z quasars can be unambiguously discriminated from the colour of T -dwarfs - the only potential source of contamination. If exec uted over two years, this programme will be competitive with the VISTA surveys; its outcome, z - 7 quasars will remain targets of interest for certainly more than a decade. In addition to the very high legacy value that high z quasars will have, this progr amme, as a near IR follow-up of the CFHT-LS fields, will also have a very strong and long lasting legacy value.

Thermal Emission of Transiting Exoplanets (TETrEs):

Probing the Diversity of Hot Jupiter Atmospheres with Multi-Wavelength Precision Photometry

PI: Jayawardhana

Instrument: WIRCam. 168 hours over [2010B-2012B]

53% Validated

Of the growing population of `hot Jupiters', those caught in transit and secondary eclipse are best suited for detailed characterization. Thermal emission from several such planets has now been measured, first with Spitzer and HST and later with ground-based telescopes. We have used CFHT/WIRCam in an optimized mode to detect the secondary eclipses of four hot Jupiters so far in the near-infrared, at or near the planets' blackbody peaks. Our measurements are the most precise yet from the ground, and include the first ground-based H and J detections. The results to date suggest a remarkable diversity of atmospheric characteristics among these worlds. We propose to build upon these exciting recent findings and explore that diversity further by targeting all extra-solar planets favorable for ground-based secondary eclipse detections in a CFHT Large Program using WIRCam. Our multi-wavelength observations will reveal the planets' dayside temperatures, probe the redistribution of heat at various atmospheric depths, search for temperature inversions, and provide constraints on the planetary energy budgets and orbital eccentricities, thus dramatically advancing our understanding of the underlying physics. The proposed Large Program, exploiting the large field-of-view and on-chip guiding of WIRCam and the unprecedented photometric precision we have already demonstrated with it, will position CFHT at the forefront of extra-solar planet research. It fills a unique niche in the near-infrared, in the absence of NICMOS on HST and prior to the launch of JWST, and will complement longer-wavelength observations with warm Spitzer and optical observations with CoRoT and Kepler.

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