dc.contributor.author |
Avdan S. |
|
dc.contributor.author |
Akyuz A. |
|
dc.contributor.author |
Vinokurov A. |
|
dc.contributor.author |
Aksaker N. |
|
dc.contributor.author |
Avdan H. |
|
dc.contributor.author |
Fabrika S. |
|
dc.contributor.author |
Valeev A. |
|
dc.contributor.author |
Akkaya-Oralhan I. |
|
dc.contributor.author |
Balman Ş. |
|
dc.date.accessioned |
2020-01-15T20:52:19Z |
|
dc.date.available |
2020-01-15T20:52:19Z |
|
dc.date.issued |
2019 |
|
dc.identifier.issn |
0004-637X |
|
dc.identifier.uri |
https://dspace.kpfu.ru/xmlui/handle/net/155471 |
|
dc.description.abstract |
© 2019. The American Astronomical Society. All rights reserved. We report the identification of the possible optical counterparts of five out of seven ultraluminous X-ray sources (ULXs) in the galaxy pair NGC 4490/4485. Using archival Hubble Space Telescope (HST) imaging data, we identified a single optical candidate for two ULXs (X-4 and X-7) and multiple optical candidates for the other three (X-2, X-3, and X-6) within ∼0.″2 error radius at the 90% confidence level. Of the two remaining ULXs, X-1 has no HST imaging data, and photometry could not be performed due to the position of X-5 in NGC 4490. Absolute magnitudes (M V) of the optical candidates lie between -5.7 and -3.8. Color-magnitude diagrams have been used to investigate the properties of the counterparts and their environments. The locations of the counterparts of X-2, X-4, and X-6 suggest possible association with a nearby group of stars, while the others have no association with a star cluster or group of stars. For comparison purposes, we analyzed three previously unused archival XMM-Newton observations. The long-term X-ray light curves of the sources (except transient X-7) show variability by a factor of three on a timescale of more than a decade. The use of a disk blackbody model for the mass of the compact objects indicates that these objects most likely have masses in the range 10-15 M. |
|
dc.relation.ispartofseries |
Astrophysical Journal |
|
dc.subject |
galaxies: individual (NGC 4490/4485) |
|
dc.subject |
X-rays: general |
|
dc.title |
Optical Counterparts of ULXs and Their Host Environments in NGC 4490/4485 |
|
dc.type |
Article |
|
dc.relation.ispartofseries-issue |
1 |
|
dc.relation.ispartofseries-volume |
875 |
|
dc.collection |
Публикации сотрудников КФУ |
|
dc.source.id |
SCOPUS0004637X-2019-875-1-SID85067206091 |
|