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Title: THE GOULD’S BELT DISTANCES SURVEY (GOBELINS). II. DISTANCES AND STRUCTURE TOWARD THE ORION MOLECULAR CLOUDS

Abstract

We present the results of the Gould’s Belt Distances Survey of young star-forming regions toward the Orion Molecular Cloud Complex. We detected 36 young stellar objects (YSOs) with the Very Large Baseline Array, 27 of which have been observed in at least three epochs over the course of two years. At least half of these YSOs belong to multiple systems. We obtained parallax and proper motions toward these stars to study the structure and kinematics of the Complex. We measured a distance of 388 ± 5 pc toward the Orion Nebula Cluster, 428 ± 10 pc toward the southern portion L1641, 388 ± 10 pc toward NGC 2068, and roughly ∼420 pc toward NGC 2024. Finally, we observed a strong degree of plasma radio scattering toward λ Ori.

Authors:
;  [1]; ; ; ; ;  [2];  [3];  [4];  [5];  [6];  [7];  [8];  [9];  [10]
  1. Department of Astronomy, University of Michigan, 1085 S. University Street, Ann Arbor, MI 48109 (United States)
  2. Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de Mexico, Morelia 58089 (Mexico)
  3. National Radio Astronomy Observatory, Domenici Science Operations Center, 1003 Lopezville Road, Socorro, NM 87801 (United States)
  4. Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany)
  5. Centro Universitario de Tonalá, Universidad de Guadalajara, Avenida Nuevo Perifrico No. 555, Ejido San José, Tatepozco, C.P. 48525, Tonalá, Jalisco, México (Mexico)
  6. Université Grenoble Alpes, IPAG, F-38000, Grenoble (France)
  7. Division of Physics, Math and Astronomy, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States)
  8. Department of Astronomy, The University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States)
  9. Cerro Tololo Interamerican Observatory, Casilla 603, La Serena (Chile)
  10. Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 West Brooks Street, Norman, OK 73019 (United States)
Publication Date:
OSTI Identifier:
22661363
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 834; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLOUDS; DISTANCE; NEBULAE; PLASMA; PROPER MOTION; SCATTERING; STAR CLUSTERS; STAR EVOLUTION; STARS

Citation Formats

Kounkel, Marina, Hartmann, Lee, Loinard, Laurent, Ortiz-León, Gisela N., Rodríguez, Luis F., Pech, Gerardo, Rivera, Juana L., Mioduszewski, Amy J., Dzib, Sergio A., Torres, Rosa M., Galli, Phillip A. B., Boden, Andrew F., Evans II, Neal J., Briceño, Cesar, and Tobin, John J., E-mail: mkounkel@umich.edu. THE GOULD’S BELT DISTANCES SURVEY (GOBELINS). II. DISTANCES AND STRUCTURE TOWARD THE ORION MOLECULAR CLOUDS. United States: N. p., 2017. Web. doi:10.3847/1538-4357/834/2/142.
Kounkel, Marina, Hartmann, Lee, Loinard, Laurent, Ortiz-León, Gisela N., Rodríguez, Luis F., Pech, Gerardo, Rivera, Juana L., Mioduszewski, Amy J., Dzib, Sergio A., Torres, Rosa M., Galli, Phillip A. B., Boden, Andrew F., Evans II, Neal J., Briceño, Cesar, & Tobin, John J., E-mail: mkounkel@umich.edu. THE GOULD’S BELT DISTANCES SURVEY (GOBELINS). II. DISTANCES AND STRUCTURE TOWARD THE ORION MOLECULAR CLOUDS. United States. doi:10.3847/1538-4357/834/2/142.
Kounkel, Marina, Hartmann, Lee, Loinard, Laurent, Ortiz-León, Gisela N., Rodríguez, Luis F., Pech, Gerardo, Rivera, Juana L., Mioduszewski, Amy J., Dzib, Sergio A., Torres, Rosa M., Galli, Phillip A. B., Boden, Andrew F., Evans II, Neal J., Briceño, Cesar, and Tobin, John J., E-mail: mkounkel@umich.edu. Tue . "THE GOULD’S BELT DISTANCES SURVEY (GOBELINS). II. DISTANCES AND STRUCTURE TOWARD THE ORION MOLECULAR CLOUDS". United States. doi:10.3847/1538-4357/834/2/142.
@article{osti_22661363,
title = {THE GOULD’S BELT DISTANCES SURVEY (GOBELINS). II. DISTANCES AND STRUCTURE TOWARD THE ORION MOLECULAR CLOUDS},
author = {Kounkel, Marina and Hartmann, Lee and Loinard, Laurent and Ortiz-León, Gisela N. and Rodríguez, Luis F. and Pech, Gerardo and Rivera, Juana L. and Mioduszewski, Amy J. and Dzib, Sergio A. and Torres, Rosa M. and Galli, Phillip A. B. and Boden, Andrew F. and Evans II, Neal J. and Briceño, Cesar and Tobin, John J., E-mail: mkounkel@umich.edu},
abstractNote = {We present the results of the Gould’s Belt Distances Survey of young star-forming regions toward the Orion Molecular Cloud Complex. We detected 36 young stellar objects (YSOs) with the Very Large Baseline Array, 27 of which have been observed in at least three epochs over the course of two years. At least half of these YSOs belong to multiple systems. We obtained parallax and proper motions toward these stars to study the structure and kinematics of the Complex. We measured a distance of 388 ± 5 pc toward the Orion Nebula Cluster, 428 ± 10 pc toward the southern portion L1641, 388 ± 10 pc toward NGC 2068, and roughly ∼420 pc toward NGC 2024. Finally, we observed a strong degree of plasma radio scattering toward λ Ori.},
doi = {10.3847/1538-4357/834/2/142},
journal = {Astrophysical Journal},
number = 2,
volume = 834,
place = {United States},
year = {Tue Jan 10 00:00:00 EST 2017},
month = {Tue Jan 10 00:00:00 EST 2017}
}
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  • We present a survey of the Orion A and B molecular clouds undertaken with the IRAC and MIPS instruments on board Spitzer. In total, five distinct fields were mapped, covering 9 deg{sup 2} in five mid-IR bands spanning 3-24 {mu}m. The survey includes the Orion Nebula Cluster, the Lynds 1641, 1630, and 1622 dark clouds, and the NGC 2023, 2024, 2068, and 2071 nebulae. These data are merged with the Two Micron All Sky Survey point source catalog to generate a catalog of eight-band photometry. We identify 3479 dusty young stellar objects (YSOs) in the Orion molecular clouds by searchingmore » for point sources with mid-IR colors indicative of reprocessed light from dusty disks or infalling envelopes. The YSOs are subsequently classified on the basis of their mid-IR colors and their spatial distributions are presented. We classify 2991 of the YSOs as pre-main-sequence stars with disks and 488 as likely protostars. Most of the sources were observed with IRAC in two to three epochs over six months; we search for variability between the epochs by looking for correlated variability in the 3.6 and 4.5 {mu}m bands. We find that 50% of the dusty YSOs show variability. The variations are typically small ({approx}0.2 mag) with the protostars showing a higher incidence of variability and larger variations. The observed correlations between the 3.6, 4.5, 5.8, and 8 {mu}m variability suggests that we are observing variations in the heating of the inner disk due to changes in the accretion luminosity or rotating accretion hot spots.« less
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