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Table · dataset · 2017

10 SALT spectra of HE 0435-4312

Listed in IVOA Registry (Virtual Observatory)

The MgII emission line is visible in the optical band for intermediate redshift quasars (0.4<z<1.6) and it is thus an extremely important tool to measure the black hole mass and to understand the structure of the Broad Line Region.

Description

We aim to determine the substructure and the variability of the MgII line with the aim to identify which part of the line comes from a medium in Keplerian motion. Using the Southern African Large Telescope (SALT) with the Robert Stobie Spectrograph (RSS) we performed ten spectroscopic observations of quasar HE 0435-4312 (z=1.2231) over a period of three years (Dec 23/24, 2012 to Dec 7/8, 2015).

Both the MgII line and the FeII pseudo-continuum increase with time. We clearly detect the systematic shift of the MgII line with respect to the FeII over the years, corresponding to the acceleration of 104+/-14km/s/year in the quasar rest frame. The MgII line shape is clearly non-Gaussian but single-component, and the increase in line equivalent width and line shift is not accompanied with significant evolution of the line shape.

Read the rest (2 more)

We analyse the conditions in the MgII and FeII formation region and we note that the very large difference in the covering factor and the turbulent velocity also support the conclusion that the two regions are spatially separated. The measured acceleration of the line systematic shift is too large to connect it with the orbital motion at a distance of the Broad Line Region (BLR) in this source. It may imply a precessing inner disk illuminating the BLR.

Further monitoring is still needed to better constrain the variability mechanism.

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Where it is published

Documentation and papers

Catalogue records · 2

Topics

Stated by source
Optical
Inferred from text
Astronomical sciences 71%
Provenance · 1 source records, 9 field assertions
SourceKeyLast seenRaw
IVOA Registry (Virtual Observatory)ivo://cds.vizier/j/a+a/601/a3212 d agoJSON v1
FieldAssertionExtractorEvidence
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concepts[field].anzsrc:group:5101enrichment · IVOA Registrytaxonomy-embedding@1.0.0title+keywords+description (71%)
concepts[field].local:field:astronomymapping · IVOA Registryconnector:ivoa_registry@1.0.0
concepts[modality].ivoa_waveband:opticalsource · IVOA Registryconnector:ivoa_registry@1.0.0
descriptionsource · IVOA Registryconnector:ivoa_registry@1.0.0rr.resource.res_description
license_textsource · IVOA Registryconnector:ivoa_registry@1.0.0
publication_datesource · IVOA Registryconnector:ivoa_registry@1.0.0
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updated_datesource · IVOA Registryconnector:ivoa_registry@1.0.0