J/A+A/391/641 Spectroscopic study of sigma Geminorum from IUE (Ekmekci+, 2002)
IUE-newsips spectra of σ Geminorum
Ekmekci F., Karakus O.
<Astron. Astrophys. 391, 641 (2002)>
=2002A&A...391..641E 2002A&A...391..641E
ADC_Keywords: Binaries, spectroscopic ; Spectra, ultraviolet ; Equivalent widths
Keywords: stars: activity - stars: atmospheres -
stars: binaries: spectroscopic - stars: chromospheres -
stars: individual: σ Gem - stars: late-type
Abstract:
The IUE spectra of σ Gem have been taken from the NASA IUE
archive using IDL (Interactive Data Language). The spectra have been
observed in 1979-1986 period. All the spectra analysed in the present
study have NEWSIPS reductions and consist of 25 LWP, 8 LWR and 5 SWP
images in high resolution, and 2 LWP and 14 SWP images in low
dispersion. The emission lines, identified as activity indicators and
originating in the chromosphere and transition region, are seen in the
spectra. The emission line fluxes and equivalent widths are computed
based on Gaussian profile fitting procedures to examine the existence
of any line flux variation that depends on time or orbital phase. It
was found that there is a flux variation with time and orbital phase
that is in good agreement with the photometric light curve variation.
By comparing the flux variation with simultaneous light curve
variation, it can be shown that there is a relation between the
ultraviolet flux variation and the spot activity of the system, as
shown by Ayres et al. (1984ApJ...279..197A 1984ApJ...279..197A) and Engvold et al.
(1988A&A...192..234E 1988A&A...192..234E) based on their IUE (with IUESIPS reduction)
spectral analysis. Moreover, it was inferred that there is no
ultraviolet excess in σ Gem by comparing the spectra of β
Gem taken as a comparison star. The Mg II h and k radial velocity
curves of σ Gem were in a good agreement with data obtained by
Eker (1986MNRAS.221..947E 1986MNRAS.221..947E) and Duemmler et al. (1997A&AS..123..209D 1997A&AS..123..209D).
Objects:
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RA (2000) DE Designation(s)
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07 43 18.7 +28 53 00 sigma Gem = HD 62044
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3a.dat 161 12 The integrated line fluxes appeared in the low
dispersion IUE spectra of sigma Gem
table3b.dat 161 12 Equivalent widths of emission lines appeared in
the low dispersion IUE spectra of sigma Gem
mg2.dat 93 33 The integrated fluxes and equivalent widths of
MgIIh(lambda 2803Å) and MgIIk(lambda 2796Å)
lines, and the MgII radial velocities, deduced
from high resolution IUE spectra of sigma Gem
(tables 4, 5 and 7)
table6.dat 49 12 Some integrated emission line fluxes of SWP
high resolution IUE spectra of sigma Gem
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Byte-by-byte Description of file: table3a.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ion Ion designation
8- 11 F4.2 10-15W/m2 FSWP06872 Flux on SWP06872 image
13- 16 F4.2 10-15W/m2 e_FSWP06872 rms uncertainty on FSWP06872
19- 22 F4.2 10-15W/m2 FSWP06873 Flux on SWP06873 image
24- 27 F4.2 10-15W/m2 e_FSWP06873 rms uncertainty on FSWP06873
30- 33 F4.2 10-15W/m2 FSWP06899 Flux on SWP06899 image
35- 38 F4.2 10-15W/m2 e_FSWP06899 rms uncertainty on FSWP06899
41- 44 F4.2 10-15W/m2 FSWP07265 Flux on SWP07265 image
46- 49 F4.2 10-15W/m2 e_FSWP07265 rms uncertainty on FSWP07265
52- 55 F4.2 10-15W/m2 FSWP07970 Flux on SWP07970 image
57- 60 F4.2 10-15W/m2 e_FSWP07970 rms uncertainty on FSWP07970
63- 66 F4.2 10-15W/m2 FSWP24090 ? Flux on SWP24090 image
68- 71 F4.2 10-15W/m2 e_FSWP24090 ? rms uncertainty on FSWP24090
75- 78 F4.2 10-15W/m2 FSWP24099 ? Flux on SWP24099 image
80- 83 F4.2 10-15W/m2 e_FSWP24099 ? rms uncertainty on FSWP24099
86- 89 F4.2 10-15W/m2 FSWP24100 ? Flux on SWP24100 image
91- 94 F4.2 10-15W/m2 e_FSWP24100 ? rms uncertainty on FSWP24100
97-100 F4.2 10-15W/m2 FSWP24101 ? Flux on SWP24101 image
102-105 F4.2 10-15W/m2 e_FSWP24101 ? rms uncertainty on FSWP24101
108-111 F4.2 10-15W/m2 FSWP24171 ? Flux on SWP24171 image
113-116 F4.2 10-15W/m2 e_FSWP24171 ? rms uncertainty on FSWP24171
119-122 F4.2 10-15W/m2 FSWP24172 ? Flux on SWP24172 image
124-127 F4.2 10-15W/m2 e_FSWP24172 ? rms uncertainty on FSWP24172
130-133 F4.2 10-15W/m2 FSWP24173 ? Flux on SWP24173 image
135-138 F4.2 10-15W/m2 e_FSWP24173 ? rms uncertainty on FSWP24173
141-144 F4.2 10-15W/m2 FSWP24178 ? Flux on SWP24178 image
146-149 F4.2 10-15W/m2 e_FSWP24178 ? rms uncertainty on SWP24178
152-155 F4.2 10-15W/m2 FSWP24179 ? Flux on SWP24179 image
157-160 F4.2 10-15W/m2 e_FSWP24179 ? rms uncertainty on FSWP24179
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Byte-by-byte Description of file: table3b.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ion Ion designation
8- 11 F4.2 0.1nm EW0.64A ? Equivalent width on phase 0.64
13- 16 F4.2 0.1nm e_EW0.64A ? rms uncertainty on EW0.64A
19- 22 F4.2 0.1nm EW0.64B ? Equivalent width on phase 0.64
24- 27 F4.2 0.1nm e_EW0.64B ? rms uncertainty on EW0.64B
30- 33 F4.2 0.1nm EW0.80 ? Equivalent width on phase 0.80
35- 38 F4.2 0.1nm e_EW0.80 ? rms uncertainty on EW0.80
41- 44 F4.2 0.1nm EW0.95 ? Equivalent width on phase 0.95
46- 49 F4.2 0.1nm e_EW0.95 ? rms uncertainty on EW0.95
52- 55 F4.2 0.1nm EW0.03 ? Equivalent width on phase 0.03
57- 60 F4.2 0.1nm e_EW0.03 ? rms uncertainty on EW0.03
63- 66 F4.2 0.1nm EW0.13 ? Equivalent width on phase 0.13
68- 71 F4.2 0.1nm e_EW0.13 ? rms uncertainty on EW0.13
74- 78 F5.2 0.1nm EW0.18A ? Equivalent width on phase 0.18
80- 83 F4.2 0.1nm e_EW0.18A ? rms uncertainty on EW0.18A
86- 89 F4.2 0.1nm EW0.18B ? Equivalent width on phase 0.18
91- 94 F4.2 0.1nm e_EW0.18B ? rms uncertainty on EW0.18B
97-100 F4.2 0.1nm EW0.18C ? Equivalent width on phase 0.18
102-105 F4.2 0.1nm e_EW0.18C ? rms uncertainty on EW0.18C
108-111 F4.2 0.1nm EW0.78 ? Equivalent width on phase 0.78
113-116 F4.2 0.1nm e_EW0.78 ? rms uncertainty on EW0.78
119-122 F4.2 0.1nm EW0.79A ? Equivalent width on phase 0.79
124-127 F4.2 0.1nm e_EW0.79A ? rms uncertainty on EW0.79A
130-133 F4.2 0.1nm EW0.79B ? Equivalent width on phase 0.79
135-138 F4.2 0.1nm e_EW0.79B ? rms uncertainty on EW0.79B
141-144 F4.2 0.1nm EW0.84A ? Equivalent width on phase 0.84
146-149 F4.2 0.1nm e_EW0.84A ? rms uncertainty on EW0.84A
152-155 F4.2 0.1nm EW0.84B ? Equivalent width on phase 0.84
157-160 F4.2 0.1nm e_EW0.84B ? rms uncertainty on EW0.84B
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Byte-by-byte Description of file: mg2.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Image Image designation
10- 19 F10.2 d JD Julian date
21- 24 F4.2 --- Phase Phase
26- 30 F5.2 10-5W/m2 FMgIIh Flux of MgII h(lambda 2803) line
32- 35 F4.2 10-5W/m2 e_FMgIIh rms uncertainty on FMgIIh
37- 40 F4.2 0.1nm EWMgIIh Equivalent width of MgII h(lambda 2803) line
42- 46 F5.2 0.1pm e_EWMgIIh rms uncertainty on EWMgIIh
48- 52 F5.2 10-5W/m2 FMgIIk ? Flux of MgII k(lambda 2796) line
54- 57 F4.2 10-5W/m2 e_FMgIIk ? rms uncertainty on FMgIIk
59- 62 F4.2 0.1nm EWMgIIk ? Equivalent width of MgII k(lambda 2796)
line
64- 68 F5.2 0.1pm e_EWMgIIk ? rms uncertainty on EWMgIIk
70- 74 F5.2 km/s RV(MgIIh) ? Radial velocity of MgII h line
76- 80 F5.2 km/s e_RV(MgIIh) ? rms uncertainty on RV(MgIIh)
82- 86 F5.2 km/s RV(MgIIk) ? Radial velocity of MgII k line
89- 93 F5.2 km/s e_RV(MgIIk) ? rms uncertainty on RV(MgIIk)
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ion Ion designation
7- 10 I4 0.1nm Lambda Wavelength of the ion
12- 15 F4.2 10-15W/m2 FSWP16943 Flux on image SWP16943,
at JD=2445099.86 (10.May.82), on phase 0.50
17- 20 F4.2 10-15W/m2 FSWP16944 Flux on image SWP16944,
at JD=2445100.86 (11.May.82), on phase 0.55
22- 25 F4.2 10-15W/m2 FSWP24078 Flux on image SWP24078,
at JD=2445973.13 (29.Sep.84), on phase 0.05
27- 30 F4.2 10-15W/m2 FSWP24107 Flux on image SWP24107,
at JD=2445977.43 (03.Oct.84), on phase 0.28
32- 35 F4.2 10-15W/m2 FSWP24124 Flux on image SWP24124,
at JD=2445979.41 (05.Oct.84), on phase 0.36
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Table 8: Orbital elements of sigma Gem obtained from the MgII radial velocity
curve analysis. The results of Duemmler et al. (1997A&AS..123..209D 1997A&AS..123..209D)
and of Bopp & Dempsey (1989PASP..101..516B 1989PASP..101..516B) are given for a comparison
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Orbital elements Duemmler et al. (1997) Bopp & Dempsey (1989) This Study
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P(day) 19.604471±0.00 19.60447±0.00007 19.607±0.008
Gamma (km/s) 44.48±0.14 43.78±0.17 49.42±1.87
K (km/s) 35.06±0.19 34.79±0.25 34.86±2.33
e 0.00±0.00 0.02110±0.0069 0.00
omega (deg) 0.00±0.00 160±20 0.00
Tconj (HJD) 2447227.220±0.015 2447227.08±0.02 2445972.53±0.28
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Table 9: The integrated fluxes for continuum levels of beta Gem and sigma Gem
between 2200Å and 3350Å.
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Star Te(K) Image JD f(int) (erg/cm2) F(int) (erg/cm2)
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beta Gem 4800 LWR15070 2447579.33 6.82(0.03) E(-8) 1.12(0.05) E(+8)
sigma Gem 4600 LWR15076 2447580.33 3.14(0.08) E(-9) 9.88(0.25) E(+7)
sigma Gem 4600 LWR15077 2447580.36 3.49(0.06) E(-9) 11.00(0.89) E(+7)
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Table 10: The ratios of integrated continuum (surface) fluxes.
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sigma Gem beta Gem DELTA PHI
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d(pc) R/R☉ d(pc) R/R☉
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58.8 14.7 10.34 11.3 0.9288 1.1012
58.8 12.0 10.34 11.3 1.3938 1.6525
58.8 14.7 10.34 9.0 0.5892 0.6985
58.8 12.0 10.34 9.0 0.8842 1.0483
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Table 11: The same ratios as given in Table 10 but with different
radii and distances given in the HIP catalogue.
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sigma Gem beta Gem DELTA PHI
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d(pc) R/R{sun} d(pc) R/R{sun}
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37.5 8.8 10.34 11.3 1.0542 1.2498
37.5 12.0 10.34 11.3 0.5669 0.6721
37.5 8.8 10.34 9.0 0.6687 0.7928
37.5 12.0 10.34 9.0 0.3596 0.4264
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Acknowledgements: Fehmi Ekmekci
(End) Patricia Bauer [CDS] 06-Aug-2002