References of "Gosset, Eric"
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See detailThe possible biperiodicity of WR 40
Gosset, Eric ULg; Vreux, Jean-Marie ULg

in Astronomy and Astrophysics (1990), 231

Strong arguments are presented in favor of the simultaneous presence of two periodicities in the variability of the Wolf-Rayet star WR 40. The frequencies are nu(A) = 0.16/d and nu(B) = 0.40/d. Some ... [more ▼]

Strong arguments are presented in favor of the simultaneous presence of two periodicities in the variability of the Wolf-Rayet star WR 40. The frequencies are nu(A) = 0.16/d and nu(B) = 0.40/d. Some uncertainties remain concerning the choice of the actual one-year alias. On the basis of a detailed statistical analysis, reliable evidence that the variability related to nu(B) could be coherent is also presented: this points out nu(B) as a possible fundamental frequency linked to the 'core' of WR 40. No firm conclusion could be drawn about nu(A), suggesting that it could be a recurrent quasi-periodicity or a second order periodicity (e.g., a beat frequency). The two frequencies are sometimes hidden by the white noise, or slightly correlated, random process that constitutes the third component of the variability of WR 40. [less ▲]

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See detailAnalysis of the photometric variability of WR40
Gosset, Eric ULg; Vreux, Jean-Marie ULg; Manfroid, Jean ULg et al

in Monthly Notices of the Royal Astronomical Society (1989), 238

New photometric data on the star WR40 are presented and, together with data already published, are analyzed in a detailed and homogeneous manner in order to investigate the variability of the star. Good ... [more ▼]

New photometric data on the star WR40 are presented and, together with data already published, are analyzed in a detailed and homogeneous manner in order to investigate the variability of the star. Good evidence is presented for the existence of a periodicity P = 6.250 + or - 0.078 day with a semiamplitude of 0.010 mag in the Stromgren b filter. Only part of the 0.1 mag peak-to-peak variation of the star can be explained in this way and other interesting features of the variability are outlined. The physical origin of the periodicity is discussed. [less ▲]

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See detailNew results on the variability of some WN stars
Gosset, Eric ULg; Vreux, Jean-Marie ULg; Manfroid, Jean ULg et al

in Davidson, K.; Moffat, A. F. J.; Lamers, H.J.G.L.M. (Eds.) Physics of Luminous Blue Variables (1989)

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See detailStatistical tests applied to the spatial distribution of quasars in several fields.
Gosset, Eric ULg; Surdej, Jean ULg; Swings, Jean-Pierre ULg

in Osmer, P. S.; Porter, A. C.; Green, R. F. (Eds.) et al Optical surveys for quasars (1988)

The authors discuss the application of different statistical tests to the study of the spatial distribution of quasars. Applications to data sets of optically selected quasars lead to the detection of a ... [more ▼]

The authors discuss the application of different statistical tests to the study of the spatial distribution of quasars. Applications to data sets of optically selected quasars lead to the detection of a clustering at a typical scale of 10 arcmin. Furthermore, the spatial distribution of quasars in a field around NGC 450 shows a deviation from randomness, towards clustering, at a scale of 10 h[SUP]-1[/SUP]Mpc. [less ▲]

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See detailSurveys of Ultraviolet Excess Quasar Candidates in Three Large Fields
Swings, Jean-Pierre ULg; Surdej, Jean ULg; Gosset, Eric ULg

in Osmer, Patric S. (Ed.) Astron. Soc. of the Pac. Conf. Series: Optical Surveys for Quasars (1988)

A general description is given of the surveys performed in the fields around NGC 450 and NGC 520, and in the ESO field No. 300 with the aim of detecting ultraviolet excess quasar candidates.

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See detailA three-dimensional extended Kolmogorov-Smirnov test as a useful tool in astronomy
Gosset, Eric ULg

in Astronomy and Astrophysics (1987), 188

The authors derive a three-dimensional version of the well-known Kolmogorov-Smirnov test. Such a test is of great practical interest when one wishes to investigate the spatial distribution of a set of ... [more ▼]

The authors derive a three-dimensional version of the well-known Kolmogorov-Smirnov test. Such a test is of great practical interest when one wishes to investigate the spatial distribution of a set of data points, particularly for the case of small size samples. A comparison with assumed three-dimensional density laws is made possible for most of current applications. A table of critical values of the new statistic is given for usual significance levels; empirical formulate to simulate the asymptotic behaviour are given as well. The tree-dimensional extended two-sided Kolmogorov-Smirnov test is shown to be sufficiently distribution-free. [less ▲]

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See detailWhich photometric period for WR 16?
Manfroid, Jean ULg; Gosset, Eric ULg; Vreux, Jean-Marie ULg

in Astronomy and Astrophysics (1987), 185

Analysis of new and already published photometric observations shows that the Wolf-Rayet star WR 16 = HD 86161 is not a binary system (WR + compact, P = 5.365 d) as claimed by Moffat and Niemela (1982 ... [more ▼]

Analysis of new and already published photometric observations shows that the Wolf-Rayet star WR 16 = HD 86161 is not a binary system (WR + compact, P = 5.365 d) as claimed by Moffat and Niemela (1982). Instead it is shown that the simultaneous presence of two periodicities (about 1.3 and 2.5 days) is necessary to account for the observed variations during at least one observing run. The variability of the B9p star HD 86199, previously used as a comparison for a photometric study of WR 16, is established. [less ▲]

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See detailThe possible appearance of a second period in the WN 5 star EZ Canis Majoris
Gosset, Eric ULg; Vreux, Jean-Marie ULg

in Astronomy and Astrophysics (1987), 178

Previously published photometric data on EZ Canis Majoris are reanalyzed. It is shown by different techniques that a sine-wave type periodicity close to one third of the claimed period of P = 3[SUP]d[/SUP ... [more ▼]

Previously published photometric data on EZ Canis Majoris are reanalyzed. It is shown by different techniques that a sine-wave type periodicity close to one third of the claimed period of P = 3[SUP]d[/SUP].766 may also be present in what was considered as peculiarities in the lightcurve. The data available do not allow to known if this second period is precisely equal or only close to one third of P nor if there is some dependence between the two. In any case, the mere possible existence of such a second period is an interesting fact in the discussion concerning the possible existence of non-radial pulsations in some WR stars. [less ▲]

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See detailThe ultraviolet spectrum of the peculiar emission-line star GG Carinae
Brandi, E.; Gosset, Eric ULg; Swings, Jean-Pierre ULg

in Astronomy and Astrophysics (1987), 175

This paper presents the first study of the properties of the peculiar emission-line star GG Carinae in the ultraviolet wavelength domain. From IUE high resolution spectra, the authors investigate the ... [more ▼]

This paper presents the first study of the properties of the peculiar emission-line star GG Carinae in the ultraviolet wavelength domain. From IUE high resolution spectra, the authors investigate the behaviour of different velocities. From IUE low resolution data, they propose a value of the B-V excess of E[SUB]B-V[/SUB] = 0.52±0.04 (2σ). The continuum of GG Car from the UV to the visible is rather well represented by the theoretical flux of a T[SUB]eff[/SUB] = 18,000K Kurucz standard model atmosphere. The authors investigate also the ultraviolet light curve, which is essentially similar to the one observed in the visible (Gosset et al., 1984, 1985). [less ▲]

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See detailThe ultraviolet spectrum of the peculiar emission-line star GG Carinae - The line identifications
Brandi, E.; Gosset, Eric ULg

in Astronomy and Astrophysics. Supplement Series (1987), 68

Line features as well as the continuum of GG Carinae in the ultraviolet wavelength domain were described by Brandi et al. (1986) on the basis of a series of high and low resolution IUE spectra for which ... [more ▼]

Line features as well as the continuum of GG Carinae in the ultraviolet wavelength domain were described by Brandi et al. (1986) on the basis of a series of high and low resolution IUE spectra for which the line identifications are detailed here. The present contribution is thus the complement to the above-mentioned paper and enables the disentangling of the complex and rich spectrum of GG Carinae. [less ▲]

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See detailIs There an Alignment of Quasars Near NGC 520?
Gosset, Eric ULg; Surdej, Jean ULg; Swings, Jean-Pierre ULg

in Hewitt, Adelaide; Burbidge, Geoffrey; Fang, Li Zhi (Eds.) IAU Symposium, No. 124 "Observational Cosmology" (1987)

Three statistical tests applied to 65 UV excess objects in the field of NGC 520 lead to no detection of any significant alignment.

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See detailThe binning analysis - Towards a better significance test
Gosset, Eric ULg; Louis, Benoit

in Astrophysics & Space Science (1986), 120

The authors demonstrate that the problems encountered with the binning analysis essentially lie in the significance test which is used. They review and analyse most of the existing significance tests and ... [more ▼]

The authors demonstrate that the problems encountered with the binning analysis essentially lie in the significance test which is used. They review and analyse most of the existing significance tests and show that the use of those based on randomization processes considerably improves the situation. For the one-dimensional binning analysis, they apply the '2 within 4' randomization test whereas for the two- and the three-dimensional binning analyses they introduce two innovations: the '4 within 16' randomization test and the '8 within 64' randomization test, respectively. [less ▲]

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See detailUltraviolet Excess Quasar Candidates in Large Fields: a Status Report Concerning the NGC 450 Area
Gosset, Eric ULg; Surdej, Jean ULg; Swings, Jean-Pierre ULg

in Swarup, G.; Kapahi, V. K. (Eds.) Quasars (1986)

New results are presented based on several statistical analyses of a 25 square degree field around NGC 450. They include the detection of a clustering on a small scale (≅10 arcminutes) and possible large ... [more ▼]

New results are presented based on several statistical analyses of a 25 square degree field around NGC 450. They include the detection of a clustering on a small scale (≅10 arcminutes) and possible large scale inhomogeneities. [less ▲]

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See detailFurther investigation of the pair of quasars Q0107 - 025 A and B
Surdej, Jean ULg; Arp, H.; Gosset, Eric ULg et al

in Astronomy and Astrophysics (1986), 161

Low and intermediate dispersion spectroscopy of Q0107 - 025 A and B obtained at ESO, AAT, and MMT provide evidence for spectral differences between these two quasars. A redshift difference of 0.004 is ... [more ▼]

Low and intermediate dispersion spectroscopy of Q0107 - 025 A and B obtained at ESO, AAT, and MMT provide evidence for spectral differences between these two quasars. A redshift difference of 0.004 is found between the two objects, and forbidden emission lines due to O II (3727 A), Ne III (1815), and possibly Ne V (3426 A), are seen in the spectrum of Q0107 - 025 A, while only the forbidden Ne III line at 1815 A is possibly detected in the spectdrum of Q0107 - 025 B. No narrow absorption lines could be detected in the 3252 - 5616 A spectral range of the intermediate resolution data of either quasar, and the spectrum of quasar B is found to be steeper in the blue that of the quasar A. The possible presence of a highly redshifted cluster of galaxies in the field of these quasars is suggested by CCD photometry. [less ▲]

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See detailRadial velocities along the light curve of the peculiar emission-line star GG Carinae
Gosset, Eric ULg; Hutsemekers, Damien ULg; Swings, Jean-Pierre ULg et al

in Astronomy and Astrophysics (1985), 153

Measurements of the radial velocities of several emission and absorption lines in a large series of high dispersion spectra of the peculiar emission-line object GG Carinae are combined with the ... [more ▼]

Measurements of the radial velocities of several emission and absorption lines in a large series of high dispersion spectra of the peculiar emission-line object GG Carinae are combined with the photometric data described by Gosset et al. (1984) in an attempt to derive constraints on a qualitative physical model of this peculiar, and most probably binary, object. Previously unreported spectral features are the double absorption components of the Balmer lines and the He I absorption lines appearing around phase phi = 0.45 of the 31.02 day period deduced from the radial velocity curve. [less ▲]

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See detailHD 192163 variability revisited - A very short period WR binary or a pulsating star?
Vreux, Jean-Marie ULg; Andrillat, Y.; Gosset, Eric ULg

in Astronomy and Astrophysics (1985), 149

The present reexamination of emission line variations in HD 192163 on the basis of 23 spectra takes into account stratification effects in the atmosphere of the WR stars, as well as the necessity for a ... [more ▼]

The present reexamination of emission line variations in HD 192163 on the basis of 23 spectra takes into account stratification effects in the atmosphere of the WR stars, as well as the necessity for a high N/R ratio. Because of the peculiar shape of the profiles, the wavelength shifts are measured by comparing the position of every observation to a nearly noise-free profile that is taken as reference. The most probable period supported by the present data is either 0.45 or 0.31 days; these two periods are one-day aliases of each other. [less ▲]

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See detailQuasar Candidates in a Large Field Centered around NGC450 and the Discovery of a New Very Interesting Pair of Quasars
Swings, Jean-Pierre ULg; Surdej, Jean ULg; Henry, A. et al

in Revista Mexicana de Astronomia y Astrofisica, vol. 10 (1985), 10

Abstract image available at: http://esoads.eso.org/abs/1985RMxAA..10...91S

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See detailThe short time-scale light variability of HD 153919 revisited
Gosset, Eric ULg

in Astrophysics & Space Science (1985), 108

Using Fourier analysis techniques, the available sets of visual photometric data concerning the X-ray binary HD 153919 are analyzed in order to clear up the controversy on the possible existence or ... [more ▼]

Using Fourier analysis techniques, the available sets of visual photometric data concerning the X-ray binary HD 153919 are analyzed in order to clear up the controversy on the possible existence or absence of the small-amplitude light variability (T = about 90 min). In this work, great effort has been made to keep a good level of homogeneity and objectivity. The main conclusion is that at the 99.4-percent confidence level, a periodicty (v = 15.5/day) is detected in one data set. In this case, it is possible to conclude that the short time-scale variability does exist. No other self-conclusive detection can be definitely reported; nevertheless, at the 90-percent confidence level, the star has a tendency to vary with characteristic frequencies of about 15/day, 30/day, and possibly higher multiples. [less ▲]

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See detailCPD - 59 deg 2857 - A new red variable star
Gosset, Eric ULg; Hutsemekers, Damien ULg; Surdej, Jean ULg

in Publications of the Astronomical Society of the Pacific [=PASP] (1985), 97

Two (C3 and C4) of the four comparison stars monitored during the photometric study of the peculiar emission-line star GG Car (Gosset et al., 1984) have been found to be variable. Available photometric ... [more ▼]

Two (C3 and C4) of the four comparison stars monitored during the photometric study of the peculiar emission-line star GG Car (Gosset et al., 1984) have been found to be variable. Available photometric and spectroscopic data allow us to identify C4 with CPD - 59 deg 2857 and classify it as a late-type giant (M3-4 III) belonging to the red variable stars of the semiregular or irregular type. [less ▲]

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