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Title: THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT

Abstract

The little-studied Herbig Be star V1818 Ori is located in the direction of the southern L1641 cloud and the Mon R2 star-forming complex, and is most likely associated with the latter at a distance of ∼900 pc. A high-resolution spectrum is consistent with a spectral type around B7 V, with lines of Hα, the red Ca ii triplet, and several forbidden lines in emission. An All Sky Automated Survey V-band light curve spanning 9 yr reveals major variability with deep absorption episodes reminiscent of the UX Orionis stars. We have searched for additional young stars clustering around V1818 Ori using grism images and the 2MASS and Wide-field Infrared Survey Explorer catalogs, and have found almost two dozen fainter stars with evidence of youth. Direct images show that the bright star IRAS 05510–1025, only about 3 arcmin from V1818 Ori, is surrounded by a reflection nebula, indicating its association with a molecular cloud. A spectrum of the star shows no emission-lines, and it is found to be a close binary with late B and early G type components. Its radial velocity indicates that it is an interloper, accidentally passing through the cloud and not physically associated with V1818 Ori.

Authors:
;  [1];  [2]
  1. Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii at Manoa, 640 North Aohoku Place, Hilo, HI 96720 (United States)
  2. Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)
Publication Date:
OSTI Identifier:
22520195
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 149; Journal Issue: 3; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; CATALOGS; EMISSION SPECTRA; HERBIG-HARO OBJECTS; IMAGES; INFRARED SPECTRA; NEBULAE; RADIAL VELOCITY; REFLECTION; RESOLUTION; STAR CLUSTERS; STAR EVOLUTION; TRIPLETS; VISIBLE RADIATION

Citation Formats

Chiang, Hsin-Fang, Reipurth, Bo, and Hillenbrand, Lynne, E-mail: hchiang@ifa.hawaii.edu, E-mail: reipurth@ifa.hawaii.edu. THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT. United States: N. p., 2015. Web. doi:10.1088/0004-6256/149/3/108.
Chiang, Hsin-Fang, Reipurth, Bo, & Hillenbrand, Lynne, E-mail: hchiang@ifa.hawaii.edu, E-mail: reipurth@ifa.hawaii.edu. THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT. United States. doi:10.1088/0004-6256/149/3/108.
Chiang, Hsin-Fang, Reipurth, Bo, and Hillenbrand, Lynne, E-mail: hchiang@ifa.hawaii.edu, E-mail: reipurth@ifa.hawaii.edu. Sun . "THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT". United States. doi:10.1088/0004-6256/149/3/108.
@article{osti_22520195,
title = {THE HERBIG BE STAR V1818 ORI AND ITS ENVIRONMENT},
author = {Chiang, Hsin-Fang and Reipurth, Bo and Hillenbrand, Lynne, E-mail: hchiang@ifa.hawaii.edu, E-mail: reipurth@ifa.hawaii.edu},
abstractNote = {The little-studied Herbig Be star V1818 Ori is located in the direction of the southern L1641 cloud and the Mon R2 star-forming complex, and is most likely associated with the latter at a distance of ∼900 pc. A high-resolution spectrum is consistent with a spectral type around B7 V, with lines of Hα, the red Ca ii triplet, and several forbidden lines in emission. An All Sky Automated Survey V-band light curve spanning 9 yr reveals major variability with deep absorption episodes reminiscent of the UX Orionis stars. We have searched for additional young stars clustering around V1818 Ori using grism images and the 2MASS and Wide-field Infrared Survey Explorer catalogs, and have found almost two dozen fainter stars with evidence of youth. Direct images show that the bright star IRAS 05510–1025, only about 3 arcmin from V1818 Ori, is surrounded by a reflection nebula, indicating its association with a molecular cloud. A spectrum of the star shows no emission-lines, and it is found to be a close binary with late B and early G type components. Its radial velocity indicates that it is an interloper, accidentally passing through the cloud and not physically associated with V1818 Ori.},
doi = {10.1088/0004-6256/149/3/108},
journal = {Astronomical Journal (Online)},
number = 3,
volume = 149,
place = {United States},
year = {Sun Mar 15 00:00:00 EDT 2015},
month = {Sun Mar 15 00:00:00 EDT 2015}
}
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