Martin Houde
A5091243184- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Pulsars and Gravitational Waves Research
- Solar and Space Plasma Dynamics
- Gamma-ray bursts and supernovae
- Molecular Spectroscopy and Structure
- Astrophysical Phenomena and Observations
- Quantum optics and atomic interactions
- Atomic and Molecular Physics
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Cold Atom Physics and Bose-Einstein Condensates
- Superconducting and THz Device Technology
- Laser-Matter Interactions and Applications
- Galaxies: Formation, Evolution, Phenomena
- Spectroscopy and Laser Applications
- Optical properties and cooling technologies in crystalline materials
- Geomagnetism and Paleomagnetism Studies
- Cosmology and Gravitation Theories
- Quantum Information and Cryptography
- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
Western University
2014-2024
Polytechnique Montréal
2023
California Institute of Technology
2011-2017
Institute for Research in Immunology and Cancer
2008-2013
Université de Montréal
2000-2013
The University of Western Australia
2012
Astronomy and Space
2010
Caltech Submillimeter Observatory
1997-2006
We present λ1.3 mm CARMA observations of dust polarization toward 30 star-forming cores and 8 regions from the TADPOL survey. show maps all sources, compare ~2.5" resolution with ~20" single-dish submillimeter telescopes. Here we do not attempt to interpret detailed B-field morphology each object. Rather, use average orientations derive conclusions in a statistical sense ensemble bearing mind that these can be quite uncertain. discuss three main findings: (1) A subset sources have consistent...
We describe a method for determining the dispersion of magnetic field vectors about large-scale fields in turbulent molecular clouds. The is designed to avoid inaccurate estimates magnetohydrodynamic or - and help avoiding strengths due large-scale, non-turbulent structure when using well-known Chandrasekhar Fermi. Our also provides accurate, independent strength ratio. discuss applications clouds OMC-1, M17, DR21(Main).
We expand our study on the dispersion of polarization angles in molecular clouds. show how effect signal integration through thickness cloud as well across area subtended by telescope beam inherent to dust continuum measurements can be incorporated analysis correctly account for its measured angular and inferred turbulent large-scale magnetic field strength ratio. further evaluate correlation scale from data sufficient spatial resolution high enough sampling rate. apply results OMC-1, where...
This paper describes a James Clerk Maxwell Telescope (JCMT) legacy survey that has been awarded roughly 500 hr of observing time to be carried out from 2007 2009. In this survey, we will map with SCUBA‐2 (Submillimetre Common‐User Bolometer Array 2) almost all the well‐known low‐mass and intermediate‐mass star‐forming regions within 0.5 kpc are accessible JCMT. Most these locations associated Gould Belt. From observations, produce flux‐limited snapshot star formation near Sun, providing...
We present results of 1.3 mm dust polarization observations toward 16 nearby, low-mass protostars, mapped with ~2.5" resolution at CARMA. The show that magnetic fields in protostellar cores on scales ~1000 AU are not tightly aligned outflows from the protostars. Rather, data consistent scenarios where and preferentially misaligned (perpendicular), or they randomly aligned. If one assumes emerge along rotation axes circumstellar disks, have disrupted surrounding material, then our imply disks...
We present the first results from B-fields In STar-forming Region Observations (BISTRO) survey, using Sub-millimetre Common-User Bolometer Array 2 (SCUBA-2) camera, with its associated polarimeter (POL-2), on James Clerk Maxwell Telescope (JCMT) in Hawaii. discuss survey's aims and objectives. describe rationale behind questions which survey will aim to answer. The most important of these is role magnetic fields star formation process scale individual filaments cores dense regions. data...
We present 350 micron polarization observations of four low-mass cores containing Class 0 protostars: L483, L1157, L1448-IRS2, and Serp-FIR1. This is the second paper in a larger survey aimed at testing magnetically regulated models for core-collapse. One key prediction these that mean magnetic field core should be aligned with symmetry axis (minor axis) flattened YSO inner envelope (aka pseudodisk). Furthermore, exhibit pinched or hour-glass shaped morphology as gravity drags inward towards...
Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density velocity structures of both been carefully studied, magnetic field (B-field) properties yet be characterized. Consequently, B-fields formation evolution hub-filament systems is not well constrained. Aims. We aim understand B-field its interplay with turbulence gravity dynamical NGC 6334 filament network that harbours...
We study the turbulent velocity dispersion spectra of coexistent HCN and HCO+ molecular species as a function length scale in M17 star-forming cloud. show that observed downward shift ion's spectrum relative to neutral is readily explained by existence an ambipolar diffusion range within which ion energies dissipate differently. use these observations evaluate this decoupling how estimate strength plane-of-the-sky component embedded magnetic field completely novel way.
Prestellar cores are unique laboratories for studies of the chemical and physical conditions preceding star formation. We observed prestellar core L1544 in fundamental transition ortho-H2D+ (1_1,0-1_1,1) at different positions over 100", found a strong correlation between its abundance CO depletion factor. also present tentative detection para-D2H+ (1_1,0-1_0,1) dust emission peak. Maps N2H+, N2D+, HCO+ DCO+ used, interpreted with aid spherically symmetric model that predicts column...
We present high angular resolution dust polarization and molecular line observations carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) toward Class 0 protostar Serpens SMM1. By complementing these new from Submillimeter (SMA) archival data Combined for Research in Millimeter-wave Astronomy (CARMA) James Clerk Maxwell Telescopes (JCMT), we can compare magnetic field orientations at different spatial scales. find major changes orientation between large (~0.1 pc) scales...
We present the results of dust emission polarization measurements Ophiuchus-B (Oph-B) carried out using Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera with its associated polarimeter (POL-2) on James Clerk Maxwell Telescope (JCMT) in Hawaii. This work is part B-fields In Star-forming Region Observations (BISTRO) survey initiated to understand role magnetic fields star formation for nearby star-forming molecular clouds. a first look at geometry and strength Oph-B. The field...
Abstract We present 850 μ m imaging polarimetry data of the ρ Oph-A core taken with Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part our ongoing survey project, <?CDATA ${\boldsymbol{B}}$?> -fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify orientation magnetic field projected on plane sky at a resolution 0.01 pc. 10 subregions distinct fractions angles in 0.2 pc core; some them can be coherent structure Oph...
We present new observations of the active star-formation region NGC 1333 in Perseus molecular cloud complex from James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations (BISTRO) survey with POL-2 instrument. The BISTRO data cover entire (~1.5 pc x 2 pc) at 0.02 resolution and spatially resolve polarized emission individual filamentary structures for first time. inferred magnetic field structure is as a whole, each filament aligned different position angles relative to...
We report 850~$\mu$m dust polarization observations of a low-mass ($\sim$12 $M_{\odot}$) starless core in the $\rho$ Ophiuchus cloud, C, made with POL-2 instrument on James Clerk Maxwell Telescope (JCMT) as part JCMT B-fields In STar-forming Region Observations (BISTRO) survey. detect an ordered magnetic field projected plane sky core. The across $\sim$0.1~pc shows predominant northeast-southwest orientation centering between $\sim$40$^\circ$ to $\sim$100$^\circ$, indicating that is well...
Abstract We present 850 μ m polarimetric observations toward the Serpens Main molecular cloud obtained using POL-2 polarimeter on James Clerk Maxwell Telescope as part of B-fields In STar-forming Region Observations survey. These probe magnetic field morphology about 6000 au scales, which consists cores and six filaments with different physical properties such density star formation activity. Using histogram relative orientation (HRO) technique, we find that fields are parallel to in...
Non-ideal magnetohydrodynamic effects that rule the coupling of magnetic field to circumstellar gas during low-mass star formation process depend heavily on local physical conditions, such as ionization fraction gas. The purpose this work is observationally characterize level at small envelope radii and investigate its relation efficiency between star-forming in Class 0 protostar B335. We have obtained molecular line emission maps B335 with ALMA, which we use measure deuteration gas,...
We use extensive 350 um polarimetry and continuum maps obtained with Hertz SHARC II along HCN HCO+ spectroscopic data to trace the orientation of magnetic field in Orion A star-forming region. Using data, we find that direction projection plane sky relative integral-shaped filament varies considerably as one moves from north south. While IRAS 05327-0457 OMC-3 MMS 1-6 is primarily perpendicular it becomes better aligned at 8-9 well OMC-2 FIR 6. The 4 cloud, located between last two, a...
We apply our technique on the dispersion of magnetic fields in molecular clouds to high spatial resolution Submillimeter Array polarization data obtained for Orion KL OMC-1, IRAS 16293, and NGC 1333 4A. show how one can take advantage such characterize magnetized turbulence power spectrum inertial dissipation ranges. For we determine that range be approximately fitted with a law k^-(2.9\pm0.9) report value 9.9 mpc λ_AD, frequency cutoff presumably due turbulent ambipolar diffusion. same...
We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in massive star-forming region G358.93-0.03, which are flaring on similarly short timescales (days) as 6.668 also associated with this source. The brightest 12.178 channel increased by a factor over 700 just 50 d. found 12.229 20.347 transitions first ever reported is only fourth object to exhibit masers. maser emission appears have higher flux density than that emission, unusual. No near-infrared flare...
Abstract We report new polarimetric and photometric maps of the massive star-forming region OMC-1 using HAWC+ instrument on Stratospheric Observatory for Infrared Astronomy. present continuum measurements this at 53, 89, 154, 214 μ m angular resolutions 5″, 8″, 14″, 19″ four bands, respectively. The enable computation improved spectral energy distributions region. find that longer wavelengths, inferred magnetic field configuration matches “hourglass” seen in previous studies, indicating...
Abstract We have obtained sensitive dust continuum polarization observations at 850 μ m in the B213 region of Taurus using POL-2 on SCUBA-2 James Clerk Maxwell Telescope as part B -fields STar-forming Region Observations (BISTRO) survey. These allow us to probe magnetic field ( -field) high spatial resolution (∼2000 au or ∼0.01 pc 140 pc) two protostellar cores (K04166 and K04169) one prestellar core (Miz-8b) that lie within filament. Using Davis–Chandrasekhar–Fermi method, we estimate...
Abstract We report 850 μ m continuum polarization observations toward the filamentary high-mass star-forming region NGC 2264, taken as part of B -fields In STar forming Regions Observations large program on James Clerk Maxwell Telescope. These data reveal a well-structured nonuniform magnetic field in 2264C and 2264D regions with prevailing orientation around 30° from north to east. Field strength estimates virial analysis major clumps indicate that is globally dominated by gravity, while...