Mapping Class I Methanol Masers in the DR21 Region

ORAL

Abstract

Class I methanol masers are believed to be produced in the shock-excited environment around star-forming regions and are believed to be indicative of stages of star formation or excitation conditions. We report on the first EVLA observations of the 36-GHz methanol masers as well as on Submillimeter Array observations of the 229-GHz methanol masers in DR21OH, DR21N, and DR21W. The data are compared to existing Class I methanol data in other transitions in each region. In the outflow of DR21OH, the distribution of the 36-GHz masers is similar to that of the other transitions. At the main continuum source in this region, the 36- and 229-GHz masers virtually overlap with the Class II 6.7-GHz masers. To the south of the region, 36-GHz masers are scattered with 44-GHz masers, but the two transitions do not appear coincident. A magnetic field of 58.1$\pm $6.2 mG is detected in DR21W. If this magnetic field is related to the density with usual scaling, the resultant high density may be indicative of an alternative pumping scheme than that commonly assumed for Class I masers.

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Authors

  • Talitha Muehlbrad

    Texas Lutheran University

  • V. Fish

    MIT Haystack Observatory

  • P. Pratap

    MIT Haystack Observatory

  • Andrey Chabanov

    West Texas A\&M University, Rhodes College, Texas Woman's University, University of Texas at San Antonio, Texas A\&M University, Department of Physics, University of Texas at Arlington, Texas State University, Pajarito Scientific Corporation, Idaho National Laboratory, Duke University, UNC, Department of Chemistry, UTSA, Department of Physics and Astronomy, UTSA, The University of Texas at San Antonio, Harvar-Smithsonian Center for Astrophysics, University of New Mexico, Maria Mitchel Observatory, NRAO, University of Alabama, Trinity University, Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, V. Alecsandri College, Bacau, Romania, University of Texas at Dallas, Argonne National Laboratory, Western Michigan University, Institute of Physics, UNAM, Mexico, University of North Texas - Chemistry, University of St. Thomas, SwRI San Antonio, Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Department of Electrical and Computer Engineering, University of Texas at Arlington, Department of Physics, University of Texas at Brownsville, SciPrint.org, The University of Texas at Austin, Georgia Tech, MIT, University of Tennessee, University of Michigan, ORNL, Texas A&M University-Commerce, University of Texas San Antonio, University of Texas at Brownsville, University of Dallas, Sternberg Astronomical Institute, SwRI, CU-Boulder, SwRI/UTSA, Southwest Research Institute, JILA, University of Colorado, Department of Physics, Texas A\&M University, Stephen F. Austin State University, Angelo State University, St. Mary's University, Physics Department, University of South Florida, CINVESTAV, Queretaro, Mexico, Department of Physics, UCSD, LANSCE, Los Alamos National Laboratory, Department of Physics and Astronomy, Texas A\&M University, Texas A\&M University: Department of Physics, Texas Christian University, Fort Worth, TX, Paschal High School, Fort Worth, TX, Tarleton State University, Stephenville, TX, Paine College, Augusta, GA, University of Houston, University of Texas at Arlington, IREAP, Department of Physics, University of Maryland, Air Force Research Laboratory, Institute for Quantum Studies and Department of Physics, Texas A\&M Universtity, College Station, Texas 77843, USA, Max-Planck Institut for Kernphysik, Saupfercheckweg 1,D-69117 Heidelberg, Germany, The National Center for Mathematics and Physics, P.O. Box 6086, KACST, Riyadh 11442, Saudi Arabia

  • Andrey Chabanov

    West Texas A\&M University, Rhodes College, Texas Woman's University, University of Texas at San Antonio, Texas A\&M University, Department of Physics, University of Texas at Arlington, Texas State University, Pajarito Scientific Corporation, Idaho National Laboratory, Duke University, UNC, Department of Chemistry, UTSA, Department of Physics and Astronomy, UTSA, The University of Texas at San Antonio, Harvar-Smithsonian Center for Astrophysics, University of New Mexico, Maria Mitchel Observatory, NRAO, University of Alabama, Trinity University, Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, V. Alecsandri College, Bacau, Romania, University of Texas at Dallas, Argonne National Laboratory, Western Michigan University, Institute of Physics, UNAM, Mexico, University of North Texas - Chemistry, University of St. Thomas, SwRI San Antonio, Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Department of Electrical and Computer Engineering, University of Texas at Arlington, Department of Physics, University of Texas at Brownsville, SciPrint.org, The University of Texas at Austin, Georgia Tech, MIT, University of Tennessee, University of Michigan, ORNL, Texas A&M University-Commerce, University of Texas San Antonio, University of Texas at Brownsville, University of Dallas, Sternberg Astronomical Institute, SwRI, CU-Boulder, SwRI/UTSA, Southwest Research Institute, JILA, University of Colorado, Department of Physics, Texas A\&M University, Stephen F. Austin State University, Angelo State University, St. Mary's University, Physics Department, University of South Florida, CINVESTAV, Queretaro, Mexico, Department of Physics, UCSD, LANSCE, Los Alamos National Laboratory, Department of Physics and Astronomy, Texas A\&M University, Texas A\&M University: Department of Physics, Texas Christian University, Fort Worth, TX, Paschal High School, Fort Worth, TX, Tarleton State University, Stephenville, TX, Paine College, Augusta, GA, University of Houston, University of Texas at Arlington, IREAP, Department of Physics, University of Maryland, Air Force Research Laboratory, Institute for Quantum Studies and Department of Physics, Texas A\&M Universtity, College Station, Texas 77843, USA, Max-Planck Institut for Kernphysik, Saupfercheckweg 1,D-69117 Heidelberg, Germany, The National Center for Mathematics and Physics, P.O. Box 6086, KACST, Riyadh 11442, Saudi Arabia

  • Andrey Chabanov

    West Texas A\&M University, Rhodes College, Texas Woman's University, University of Texas at San Antonio, Texas A\&M University, Department of Physics, University of Texas at Arlington, Texas State University, Pajarito Scientific Corporation, Idaho National Laboratory, Duke University, UNC, Department of Chemistry, UTSA, Department of Physics and Astronomy, UTSA, The University of Texas at San Antonio, Harvar-Smithsonian Center for Astrophysics, University of New Mexico, Maria Mitchel Observatory, NRAO, University of Alabama, Trinity University, Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, V. Alecsandri College, Bacau, Romania, University of Texas at Dallas, Argonne National Laboratory, Western Michigan University, Institute of Physics, UNAM, Mexico, University of North Texas - Chemistry, University of St. Thomas, SwRI San Antonio, Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Department of Electrical and Computer Engineering, University of Texas at Arlington, Department of Physics, University of Texas at Brownsville, SciPrint.org, The University of Texas at Austin, Georgia Tech, MIT, University of Tennessee, University of Michigan, ORNL, Texas A&M University-Commerce, University of Texas San Antonio, University of Texas at Brownsville, University of Dallas, Sternberg Astronomical Institute, SwRI, CU-Boulder, SwRI/UTSA, Southwest Research Institute, JILA, University of Colorado, Department of Physics, Texas A\&M University, Stephen F. Austin State University, Angelo State University, St. Mary's University, Physics Department, University of South Florida, CINVESTAV, Queretaro, Mexico, Department of Physics, UCSD, LANSCE, Los Alamos National Laboratory, Department of Physics and Astronomy, Texas A\&M University, Texas A\&M University: Department of Physics, Texas Christian University, Fort Worth, TX, Paschal High School, Fort Worth, TX, Tarleton State University, Stephenville, TX, Paine College, Augusta, GA, University of Houston, University of Texas at Arlington, IREAP, Department of Physics, University of Maryland, Air Force Research Laboratory, Institute for Quantum Studies and Department of Physics, Texas A\&M Universtity, College Station, Texas 77843, USA, Max-Planck Institut for Kernphysik, Saupfercheckweg 1,D-69117 Heidelberg, Germany, The National Center for Mathematics and Physics, P.O. Box 6086, KACST, Riyadh 11442, Saudi Arabia

  • Andrey Chabanov

    West Texas A\&M University, Rhodes College, Texas Woman's University, University of Texas at San Antonio, Texas A\&M University, Department of Physics, University of Texas at Arlington, Texas State University, Pajarito Scientific Corporation, Idaho National Laboratory, Duke University, UNC, Department of Chemistry, UTSA, Department of Physics and Astronomy, UTSA, The University of Texas at San Antonio, Harvar-Smithsonian Center for Astrophysics, University of New Mexico, Maria Mitchel Observatory, NRAO, University of Alabama, Trinity University, Department of Physics and Astronomy, University of Texas at San Antonio, San Antonio, Texas 78249, V. Alecsandri College, Bacau, Romania, University of Texas at Dallas, Argonne National Laboratory, Western Michigan University, Institute of Physics, UNAM, Mexico, University of North Texas - Chemistry, University of St. Thomas, SwRI San Antonio, Alan G. MacDiarmid NanoTech Institute, University of Texas at Dallas, Department of Electrical and Computer Engineering, University of Texas at Arlington, Department of Physics, University of Texas at Brownsville, SciPrint.org, The University of Texas at Austin, Georgia Tech, MIT, University of Tennessee, University of Michigan, ORNL, Texas A&M University-Commerce, University of Texas San Antonio, University of Texas at Brownsville, University of Dallas, Sternberg Astronomical Institute, SwRI, CU-Boulder, SwRI/UTSA, Southwest Research Institute, JILA, University of Colorado, Department of Physics, Texas A\&M University, Stephen F. Austin State University, Angelo State University, St. Mary's University, Physics Department, University of South Florida, CINVESTAV, Queretaro, Mexico, Department of Physics, UCSD, LANSCE, Los Alamos National Laboratory, Department of Physics and Astronomy, Texas A\&M University, Texas A\&M University: Department of Physics, Texas Christian University, Fort Worth, TX, Paschal High School, Fort Worth, TX, Tarleton State University, Stephenville, TX, Paine College, Augusta, GA, University of Houston, University of Texas at Arlington, IREAP, Department of Physics, University of Maryland, Air Force Research Laboratory, Institute for Quantum Studies and Department of Physics, Texas A\&M Universtity, College Station, Texas 77843, USA, Max-Planck Institut for Kernphysik, Saupfercheckweg 1,D-69117 Heidelberg, Germany, The National Center for Mathematics and Physics, P.O. Box 6086, KACST, Riyadh 11442, Saudi Arabia