The ratio of the C IV$\lambda\lambda$1548,1550 rest-wavelengths from high-redshift QSO absorption lines
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We report the results of a multiwavelength study of the non-thermal radio emitter HD 168112 (O5.5III(f + )).The detailed analysis of two quasi-simultaneous XMM-Newton and VLA observations reveals strong variability of this star both in the X-ray and radio ranges.The X-ray observations separated by five months reveal a decrease of the X-ray flux of ∼30%.The radio emission on the other hand increases by a factor 5-7 between the two observations obtained roughly simultaneously with the XMM-Newton pointings.The X-ray data reveal a hard emission that is most likely produced by a thermal plasma at kT ∼ 2-3 keV while the VLA data confirm the non-thermal status of this star in the radio waveband.Comparison with archive X-ray and radio data confirms the variability of this source in both wavelength ranges over a yet ill defined time scale.The properties of HD 168112 in the X-ray and radio domain point towards a binary system with a significant eccentricity and an orbital period of a few years.However, our optical spectra reveal no significant changes of the star's radial velocity suggesting that if HD 168112 is indeed a binary, it must be seen under a fairly low inclination.
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This result is less constraining than the two previous analyses, mainly because the q-coefficients are smaller for C IV.
“This is less constraining than the two previous analyses, mainly because the q-coefficients are smaller for C IV (see Petitjean and Aracil 2004 for the calibration of the laboratory spectra).”
From Fundamental constants: from measurement to the universe, a window on gravitation and cosmology (2025) · cites this paper as Petitjean and Aracil 2004
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Self-citationC IV absorption in damped and sub-damped Lyman-α systems
Fox, A. J., Ledoux, C., Petitjean, P., & Srianand, R. (2007) · Astronomy and Astrophysics · doi:10.1051/0004-6361:20077640 · Cited by 79 · see citing works
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Self-citationFox, A. J., Ledoux, C., Petitjean, P., & Srianand, R. (2007) · arXiv (Cornell University) · doi:10.48550/arxiv.0707.4065 · Cited by 51 · see citing works
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Constraining Fundamental Constants of Physics with Quasar Absorption Line Systems
Petitjean, P., Srianand, R., Chand, H., Ivanchik, A. V., Noterdaeme, P., & Gupta, N. (2009) · Space sciences series of ISSI · doi:10.1007/978-1-4419-1362-3_21 · Cited by 1 · see citing works
Self-citation
- Authors
- Petitjean, P., & Aracil, B.
- Affiliations
- Institut d'Astrophysique de Paris (FR)
- University of Massachusetts Amherst (US)
- ORCID
- Petitjean, P.
- Venue
- Astronomy & Astrophysics
- Publisher
- EDP Sciences
- Published
- 2004-08
- Volume
- 422
- Issue
- 2
- Pages
- 523-526
- ISSN
- 0004-6361 (ISSN-L)
- 1432-0746
- OpenAlex
- W1737888242
- Cited by
- 12
- References
- 7
- Citations by year
- 2025: 2 · 2022: 1
- FWCI
- 0.98
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Astronomy and Astrophysics (publishedVersion)
- HAL (submittedVersion, other-oa)
- Funders
- National Science Foundation
- National Aeronautics and Space Administration
- National Radio Astronomy Observatory
- Associated Universities
- Fonds De La Recherche Scientifique - FNRS
- European Southern Observatory
- Services Fédéraux des Affaires Scientifiques, Techniques et Culturelles
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Stellar, planetary, and galactic studies
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Galaxies: Formation, Evolution, Phenomena
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astrophysical Phenomena and Observations
- Keywords
- non-thermal radio emission, X-ray variability, radio variability, binary stars, eccentric orbits, orbital period, radial velocity, thermal plasma, X-ray emission
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