Professor Dan Clemens

Institute for Astrophysical Research, and
Department of Astronomy, Boston University
Room 417 College of Arts and Sciences Building
725 Commonwealth Avenue
Boston, Massachusetts 02215
Office Ph: (617) 353-6140
email: 'clemens at bu.edu'

Current Course Web Site(s): GRS A713 Fall 2012 (TBD)
Professor of Astronomy; CV with Publications

Recent Courses Taught:
Fall 2010 - AS102 The Astronomical Universe
Spring 2011 - AS713 Astronomical Spectroscopy
Fall 2011 - AS710 Observational Techniques
Spring 2012 - AS441 Astronomical Observations

Director of Undergraduate Studies
Astronomy Department

At Left: Dan Clemens and Dr. Marc Buie during 2004 commissioning of the Mimir instrument on the Perkins Telescope (operated by Lowell Observatory, outside Flagstaff, AZ).

Associated Universities for Research in Astronomy:
Member Representative for Boston University
Member, Board of Directors
Chairman, Board of Directors

 

NEWS: Boston University signs with Lowell Observatory to become a partner/owner in the Discovery Channel Telescope

First Light Gala July 21 2012

 

Current Research Projects & Areas:

I work primarily on problems of Galactic astrophysics, including star formation, Galactic structure, and the interstellar medium. This decade features a coherent effort to map and study the nature of the magnetic field in the star-forming molecular gas clouds in the disk of the Milky Way through use of our Mimir instrument to conduct the Galactic Plane Infrared Polarization Survey (GPIPS). This Survey uses the weak (1-2%) linearly polarization signal impressed on unpolarized background starlight by foreground dust grains spinning about the magnetic fields present in the gas and dust clouds to reveal the plane of sky orientation of the field. GPIPS is nearly through its observations phase on the Perkins telescope in Arizona, and should be completed either late in 2012 or mid-way through 2013. The roughly 1 million polarizations being measured represent many orders of magnitude improvement in the number of probes of the magnetic field in the Galaxy.

Looking into the future, the new partnership for Boston University in the 4.3 m Discovery Channel Telescope brings great new opportunities for new science, but also the need to develop and deploy powerful new instruments to enable that science. While Mimir is a bit too big to fit at the Cass focus of the DCT, there are multi-object spectroscopic options on the DCT that will keep Mimir productive and unique for another decade or more. The key concept is called 'Flexi' - but the details have to be kept under wraps for a bit longer...

A somewhat organized list of current activities would include:

  1. The Mimir Instrument - a near-infrared wide-field imaging polarimeter and spectrometer, currently used on the 1.8m Perkins telescope.
  2. The Galactic Plane Infrared Polarization Survey (GPIPS) - an H-band imaging polarization survey of 76 sq deg of the first Galactic Quadrant
  3. Student Projects in our Research Group
  4. Collaborative Projects with outside groups:
  5. Other Projects (Internal)
    • "The Outer Magnetic Field of L183" Clemens, D. P., ApJ, 748, 18 (2012)
    • "Near-Infrared Polarimetry of a Normal Spiral Galaxy viewed through the Taurus Molecular Cloud," Clemens, et al., in prep. (2012)
    • Deep H-band Polarimetry toward the FeSt globule in the Pipe Nebula - Clemens, et al., in prep.
    • The Magnetic Context and Contents of the Orion Molecular Cloud - TBD, et al., in prep.
    • The Magnetic field of the edge-on galaxy NGC891 - TBD, et al., in prep.

     

Mimir instrument, with outer cover and thermal shield removed. Picture taken during 2010 July warm servicing. The black box contains the four filter wheels and the three-camera block.

The globular cluster GC01, found in GLIMPSE images (Kobulnicky et al. 2005), imaged here with Mimir in the JHK bands. Left image is the full 10x10 arcmin field, center images shows a zoom of the central region. Right image taken with F/17 high-resolution camera option of Mimir, with pixel sampling of 0.18 arcsec.

JHK (1.16-2.32um) spectrum of the Blue Snowball Planetary Nebula. This spectrum was obtained by students in the Fall 2010 AS102 non-majors class, as part of a field trip to the Perkin telescope.

Graduate Student Researchers: Lauren (Ren) Cashman, Sadia Hoq, Jordan Montgomery

Undergraduate Student Researchers: Pantelis Thomadis, Ian Santagata

Recent Graduates: Dr. Michael D. Pavel (2012 - to Univ. of Texas), Robert Marchwinski (to Penn State), Katie Jameson (to Univ. Maryland), Josh Shiode (to UC Berkeley), Dr. Emily Mercer (to Univ. Michigan)

Mimir H-band polarizations (yellow and red vectors) surrounding the periphery of the L183 (=L134N) dark molecular cloud. Gray scale image is WISE 12um surface brightness decrement, which is related to dust column density. From Clemens (2012)

Mimir H-band polarizations in the Scorpius calibrator field (10x10' in extent), showing the primary polarization standards (solid vectors) and the new 'secondary' standards put forward in the GPIPS Calibration paper (Clemens et al. 2012b).

One 10x10 arcmin field in the Galactic Plane, from GPIPS. There will be over 3,200 such fields when the survey is completed. (From theGPIPS First Data Release Paper)

Mimir H-band polarization vectors overlaid on WISE 12um emission gray-scale image and WISE 25um emission contours. (From Andersson et al. 2012)