Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source
X-ray quasiperiodic eruptions (QPEs) are a novel mode of variability in nearby galactic nuclei whose origin remains unknown. Their multiwavelength properties are poorly constrained, as studies have focused almost entirely on the X-ray band. Here, we report on time-resolved, coordinated Hubble Space...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal Letters |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/2041-8213/adace9 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832542735858401280 |
|---|---|
| author | T. Wevers M. Guolo S. Lockwood A. Mummery D. R. Pasham R. Arcodia |
| author_facet | T. Wevers M. Guolo S. Lockwood A. Mummery D. R. Pasham R. Arcodia |
| author_sort | T. Wevers |
| collection | DOAJ |
| description | X-ray quasiperiodic eruptions (QPEs) are a novel mode of variability in nearby galactic nuclei whose origin remains unknown. Their multiwavelength properties are poorly constrained, as studies have focused almost entirely on the X-ray band. Here, we report on time-resolved, coordinated Hubble Space Telescope far-ultraviolet (FUV) and XMM-Newton X-ray observations of the shortest period X-ray QPE source currently known, eRO-QPE2. We detect a bright UV point source ( L _FUV ≈ few × 10 ^41 erg s ^−1 ) that does not show statistically significant variability between the X-ray eruption and quiescent phases. This emission is unlikely to be powered by a young stellar population in a nuclear stellar cluster. The X-ray-to-UV spectral energy distribution can be described by a compact accretion disk ( ${R}_{{\rm{out}}}=34{3}_{-138}^{+202}\,{R}_{{\rm{g}}}$ ). Such compact disks are incompatible with typical disks in active galactic nuclei, but form naturally following the tidal disruption of a star. Our results rule out models (for eRO-QPE2) invoking (i) a classic active galactic nucleus accretion disk and (ii) no accretion disk at all. For orbiter models, the expected radius derived from the timing properties would naturally lead to disk-orbiter interactions for both quasi-spherical and eccentric trajectories. We infer a black hole mass of log _10 ( M _BH ) = 5.9 ± 0.3 M _⊙ and an Eddington ratio of 0.13 ${}_{-0.07}^{+0.18}$ ; in combination with the compact outer radius, this is inconsistent with existing disk instability models. After accounting for the quiescent disk emission, we constrain the ratio of X-ray to FUV luminosity of the eruption component to be L _X / L _FUV > 16−85 (depending on the intrinsic extinction). |
| format | Article |
| id | doaj-art-a1ca6e03a5634940856e36d96970be35 |
| institution | Kabale University |
| issn | 2041-8205 |
| language | English |
| publishDate | 2025-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astrophysical Journal Letters |
| spelling | doaj-art-a1ca6e03a5634940856e36d96970be352025-02-03T18:03:22ZengIOP PublishingThe Astrophysical Journal Letters2041-82052025-01-019801L110.3847/2041-8213/adace9Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption SourceT. Wevers0https://orcid.org/0000-0002-4043-9400M. Guolo1https://orcid.org/0000-0002-5063-0751S. Lockwood2https://orcid.org/0000-0002-0743-2645A. Mummery3D. R. Pasham4https://orcid.org/0000-0003-1386-7861R. Arcodia5https://orcid.org/0000-0003-4054-7978Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA ; twevers@schmidtsciences.org; Astrophysics & Space Institute , Schmidt Sciences, New York, NY 10011, USABloomberg Center for Physics and Astronomy, Johns Hopkins University , 3400 N. Charles Street, Baltimore, MD 21218, USASpace Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA ; twevers@schmidtsciences.orgOxford Theoretical Physics , Beecroft Building, Clarendon Laboratory, Parks Road, Oxford, OX1 3PU, UKMIT Kavli Institute for Astrophysics and Space Research , 70 Vassar Street, Cambridge, MA 02139, USAMIT Kavli Institute for Astrophysics and Space Research , 70 Vassar Street, Cambridge, MA 02139, USAX-ray quasiperiodic eruptions (QPEs) are a novel mode of variability in nearby galactic nuclei whose origin remains unknown. Their multiwavelength properties are poorly constrained, as studies have focused almost entirely on the X-ray band. Here, we report on time-resolved, coordinated Hubble Space Telescope far-ultraviolet (FUV) and XMM-Newton X-ray observations of the shortest period X-ray QPE source currently known, eRO-QPE2. We detect a bright UV point source ( L _FUV ≈ few × 10 ^41 erg s ^−1 ) that does not show statistically significant variability between the X-ray eruption and quiescent phases. This emission is unlikely to be powered by a young stellar population in a nuclear stellar cluster. The X-ray-to-UV spectral energy distribution can be described by a compact accretion disk ( ${R}_{{\rm{out}}}=34{3}_{-138}^{+202}\,{R}_{{\rm{g}}}$ ). Such compact disks are incompatible with typical disks in active galactic nuclei, but form naturally following the tidal disruption of a star. Our results rule out models (for eRO-QPE2) invoking (i) a classic active galactic nucleus accretion disk and (ii) no accretion disk at all. For orbiter models, the expected radius derived from the timing properties would naturally lead to disk-orbiter interactions for both quasi-spherical and eccentric trajectories. We infer a black hole mass of log _10 ( M _BH ) = 5.9 ± 0.3 M _⊙ and an Eddington ratio of 0.13 ${}_{-0.07}^{+0.18}$ ; in combination with the compact outer radius, this is inconsistent with existing disk instability models. After accounting for the quiescent disk emission, we constrain the ratio of X-ray to FUV luminosity of the eruption component to be L _X / L _FUV > 16−85 (depending on the intrinsic extinction).https://doi.org/10.3847/2041-8213/adace9X-ray transient sourcesHigh energy astrophysicsBlack holesTidal disruptionStellar accretion disks |
| spellingShingle | T. Wevers M. Guolo S. Lockwood A. Mummery D. R. Pasham R. Arcodia Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source The Astrophysical Journal Letters X-ray transient sources High energy astrophysics Black holes Tidal disruption Stellar accretion disks |
| title | Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source |
| title_full | Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source |
| title_fullStr | Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source |
| title_full_unstemmed | Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source |
| title_short | Time-resolved Hubble Space Telescope UV Observations of an X-Ray Quasiperiodic Eruption Source |
| title_sort | time resolved hubble space telescope uv observations of an x ray quasiperiodic eruption source |
| topic | X-ray transient sources High energy astrophysics Black holes Tidal disruption Stellar accretion disks |
| url | https://doi.org/10.3847/2041-8213/adace9 |
| work_keys_str_mv | AT twevers timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource AT mguolo timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource AT slockwood timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource AT amummery timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource AT drpasham timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource AT rarcodia timeresolvedhubblespacetelescopeuvobservationsofanxrayquasiperiodiceruptionsource |