Table · dataset · 2020
Crosscorrelation function (CCF) studies in GX 17+2
Listed in IVOA Registry (Virtual Observatory)
Neutron star Z-type sources provide a unique platform in order to understand the structure of accretion disk-corona geometry emitting close to the Eddington luminosity.
Description
Using RXTE and Nuclear Spectroscopic Telescope Array Mission (NuSTAR) satellite data, we performed crosscorrelation function (CCF) studies in GX 17+2 in order to constrain the size of the corona responsible for hard X-rays. From the RXTE data, we found that during horizontal and normal branches, the CCFs show anticorrelated hard (16-30keV) and soft (2-5keV) X-ray delays of the order of a few tens to hundred seconds with a mean correlation coefficient of 0.42+/-0.11.
Few observations shows correlated lags and, on one occasion, coincident with radio emission. We also report an anticorrelated hard X-ray delay of 113+/-51s using the NuSTAR data of GX 17+2. Based on RXTE data, we find that soft and hard X-ray fluxes are varying, indicating the changes in the disk-corona structure during delays.
Read the rest (2 more)
We bridle the size of the corona using relativistic precession, transition layer models, and boundary layer models. Assuming the delays to be a readjustment timescale of the disk-corona structure, the height of the corona was estimated to be ~17-100km. Assuming that the inner region of the truncated disk is occupied by the corona, we constrain the coronal readjustment velocities (v_corona_={beta}v_disk_, where v_disk_ is the radial velocity component of the disk) of the order of {beta}=0.06-0.12.
This study indicates that the observed delays are primarily dependent on the varying coronal readjustment velocities.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/244/5 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2019ApJS..244....5S ui.adsabs.harvard.edu/abs/2019ApJS..244....5S ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/apjs/244/5 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- X-Ray
- From keywords
- Astronomy & Astrophysics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/apjs/244/5 | 14 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:x-ray | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |