TY - JOUR
T1 - Slow decline and rise of the broad [O III] emission line in globular cluster black hole candidate RZ2109
AU - Dage, Kristen C.
AU - Zepf, Stephen E.
AU - Bahramian, Arash
AU - Strader, Jay
AU - Maccarone, Thomas J.
AU - Peacock, Mark B.
AU - Kundu, Arunav
AU - Steele, Matthew M.
AU - Britt, Christopher T.
N1 - Funding Information:
KCD, SEZ, and MBP acknowledge support from Chandra grant GO4-15089A. SEZ and MBP also acknowledge support from the NASA ADAP grant NNX15AI71G. This research is based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Ministério da Ciência, Tecnologia, e Inovac¸ão (MCTI) da República Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. We also acknowledge use of NASA’s Astrophysics Data System and Arxiv. KCD acknowledges Jamie Kennea and the Swift ToO Team, and thanks James Miller-Jones and ICRAR/Curtin University. JS acknowledges support from the Packard Foundation. The authors thank the referee for thoughtful and insightful comments.
Funding Information:
KCD, SEZ, and MBP acknowledge support from Chandra grant GO4-15089A. SEZ and MBP also acknowledge support from the NASA ADAP grant NNX15AI71G. This research is based on observations obtained at the Southern Astrophysical Research (SOAR) telescope, which is a joint project of the Minist?rio da Ci?ncia, Tecnologia, e Inova??o (MCTI) da Rep?blica Federativa do Brasil, the U.S. National Optical Astronomy Observatory (NOAO), the University of North Carolina at Chapel Hill (UNC), and Michigan State University (MSU). This research has made use of the XRT Data Analysis Software (XRTDAS) developed under the responsibility of the ASI Science Data Center (ASDC), Italy. We also acknowledge use of NASA?s Astrophysics Data System and Arxiv. KCD acknowledges Jamie Kennea and the Swift ToO Team, and thanks James Miller-Jones and ICRAR/Curtin University. JS acknowledges support from the Packard Foundation. The authors thank the referee for thoughtful and insightful comments. The following software and packages were used for analysis: IRAF, distributed by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation, SAOImage DS9, developed by Smithsonian Astrophysical Observatory, NUMPY (Van Der Walt, Colbert & Varoquaux 2011), PALETTABLE,9 and MATPLOTLIB (Hunter 2007).
Funding Information:
The following software and packages were used for analysis: IRAF, distributed by the National Optical Astronomy Observatories, which are operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National Science Foundation, SAOImage DS9, developed by Smithsonian Astrophysical Observatory, NUMPY (Van Der Walt, Colbert & Varoquaux 2011), PALETTABLE,9 and MATPLOTLIB (Hunter 2007).
Publisher Copyright:
© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2019/11/11
Y1 - 2019/11/11
N2 - RZ2109 is the first of several extragalactic globular clusters shown to host an ultraluminous X-ray source. RZ2109 is particularly notable because optical spectroscopy shows it has broad, luminous [O III] λλ4959,5007 emission, while also having no detectable hydrogen emission. The X-ray and optical characteristics of the source in RZ2109 make it a good candidate for being a stellar mass black hole accreting from a white dwarf donor (i.e. an ultracompact black hole X-ray binary). In this paper we present optical spectroscopic monitoring of the [O III]5007 emission line from 2007 to 2018. We find that the flux of the emission line is significantly lower in recent observations from 2016 to 2018 than it was in earlier observations in 2007–2011. We also explore the behaviour of the emission line shape over time. Both the core and the wings of the emission line decline over time, with some evidence that the core declines more rapidly than the wings.
AB - RZ2109 is the first of several extragalactic globular clusters shown to host an ultraluminous X-ray source. RZ2109 is particularly notable because optical spectroscopy shows it has broad, luminous [O III] λλ4959,5007 emission, while also having no detectable hydrogen emission. The X-ray and optical characteristics of the source in RZ2109 make it a good candidate for being a stellar mass black hole accreting from a white dwarf donor (i.e. an ultracompact black hole X-ray binary). In this paper we present optical spectroscopic monitoring of the [O III]5007 emission line from 2007 to 2018. We find that the flux of the emission line is significantly lower in recent observations from 2016 to 2018 than it was in earlier observations in 2007–2011. We also explore the behaviour of the emission line shape over time. Both the core and the wings of the emission line decline over time, with some evidence that the core declines more rapidly than the wings.
KW - Globular clusters: individual: RZ2109
KW - White dwarfs
UR - http://www.scopus.com/inward/record.url?scp=85075249519&partnerID=8YFLogxK
U2 - 10.1093/mnras/stz2514
DO - 10.1093/mnras/stz2514
M3 - Article
AN - SCOPUS:85075249519
SN - 0035-8711
VL - 489
SP - 4783
EP - 4790
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -