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Title: THE FAINTEST WISE DEBRIS DISKS: ENHANCED METHODS FOR DETECTION AND VERIFICATION

Abstract

In an earlier study, we reported nearly 100 previously unknown dusty debris disks around Hipparcos main-sequence stars within 75 pc by selecting stars with excesses in individual WISE colors. Here, we further scrutinize the Hipparcos  75 pc sample to (1) gain sensitivity to previously undetected, fainter mid-IR excesses and (2) remove spurious excesses contaminated by previously unidentified blended sources. We improve on our previous method by adopting a more accurate measure of the confidence threshold for excess detection and by adding an optimally weighted color average that incorporates all shorter-wavelength WISE photometry, rather than using only individual WISE colors. The latter is equivalent to spectral energy distribution fitting, but only over WISE bandpasses. In addition, we leverage the higher-resolution WISE images available through the unWISE.me image service to identify contaminated WISE excesses based on photocenter offsets among the W 3- and W 4-band images. Altogether, we identify 19 previously unreported candidate debris disks. Combined with the results from our earlier study, we have found a total of 107 new debris disks around 75 pc Hipparcos main-sequence stars using precisely calibrated WISE photometry. This expands the 75 pc debris disk sample by 22% around Hipparcos main-sequence stars and by 20% overallmore » (including non-main-sequence and non- Hipparcos stars).« less

Authors:
 [1]; ;  [2];  [3]
  1. Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)
  2. Department of Physics and Astronomy, Centre for Planetary Science and Exploration, The University of Western Ontario, 1151 Richmond St., London, ON N6A 3K7 (Canada)
  3. Institute for Astronomy, 2680 Woodlawn Dr., Honolulu, HI 96822-1839 (United States)
Publication Date:
OSTI Identifier:
22663990
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; 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; DETECTION; ENERGY SPECTRA; GAIN; IMAGES; MAIN SEQUENCE STARS; PHOTOMETRY; PROTOPLANETS; RESOLUTION; SENSITIVITY; STATISTICS; VERIFICATION; WAVELENGTHS

Citation Formats

Patel, Rahul I., Metchev, Stanimir A., Trollo, Joseph, and Heinze, Aren. THE FAINTEST WISE DEBRIS DISKS: ENHANCED METHODS FOR DETECTION AND VERIFICATION. United States: N. p., 2017. Web. doi:10.3847/1538-3881/153/2/54.
Patel, Rahul I., Metchev, Stanimir A., Trollo, Joseph, & Heinze, Aren. THE FAINTEST WISE DEBRIS DISKS: ENHANCED METHODS FOR DETECTION AND VERIFICATION. United States. doi:10.3847/1538-3881/153/2/54.
Patel, Rahul I., Metchev, Stanimir A., Trollo, Joseph, and Heinze, Aren. Wed . "THE FAINTEST WISE DEBRIS DISKS: ENHANCED METHODS FOR DETECTION AND VERIFICATION". United States. doi:10.3847/1538-3881/153/2/54.
@article{osti_22663990,
title = {THE FAINTEST WISE DEBRIS DISKS: ENHANCED METHODS FOR DETECTION AND VERIFICATION},
author = {Patel, Rahul I. and Metchev, Stanimir A. and Trollo, Joseph and Heinze, Aren},
abstractNote = {In an earlier study, we reported nearly 100 previously unknown dusty debris disks around Hipparcos main-sequence stars within 75 pc by selecting stars with excesses in individual WISE colors. Here, we further scrutinize the Hipparcos  75 pc sample to (1) gain sensitivity to previously undetected, fainter mid-IR excesses and (2) remove spurious excesses contaminated by previously unidentified blended sources. We improve on our previous method by adopting a more accurate measure of the confidence threshold for excess detection and by adding an optimally weighted color average that incorporates all shorter-wavelength WISE photometry, rather than using only individual WISE colors. The latter is equivalent to spectral energy distribution fitting, but only over WISE bandpasses. In addition, we leverage the higher-resolution WISE images available through the unWISE.me image service to identify contaminated WISE excesses based on photocenter offsets among the W 3- and W 4-band images. Altogether, we identify 19 previously unreported candidate debris disks. Combined with the results from our earlier study, we have found a total of 107 new debris disks around 75 pc Hipparcos main-sequence stars using precisely calibrated WISE photometry. This expands the 75 pc debris disk sample by 22% around Hipparcos main-sequence stars and by 20% overall (including non-main-sequence and non- Hipparcos stars).},
doi = {10.3847/1538-3881/153/2/54},
journal = {Astronomical Journal (Online)},
number = 2,
volume = 153,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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