<=== observer ===>
"RWATERS",\
"Waters, L.B.F.M.",\
"",\
"SRON Laboratory for Space Research Groningen",\
" ",\
"P.O. Box 800",\
"9700 AV ",\
"Groningen ",\
"The Netherlands",\
"31 50 634090",\
"31 50 634033",\
"rens@sron.rug.nl"
<=== proposal ===>
"BESTARS", 1, 3,\
{"circumstellar discs",\
"early-type stars",\
"stellar winds"},\
{"H.J.G.L.M. Lamers",\
"SRON Utrecht",\
"J.M. Marlborough",\
"Astronomy Department",\
"University of Wester",\
"London",\
"Ontario",\
"Canada."}
<=== title ===>
The structure of the winds of Be stars.
<=== abstract ===>
SCIENTIFIC ABSTRACT
Be stars are B-type main sequence stars or giants that show or have
shown H-alpha emission. They are on average rapid rotators, with vsini
values above 150-200 km/s. It is generally accepted that Be stars are
surrounded by a rotating circumstellar disc which is ejected by the star via a
mechanism that is as yet poorly understood. In order to improve our
knowledge of the
mechanism which forms these discs it is essential to map their density and
velocity structure, preferentially for a range of spectral types (i.e.
stellar luminositites and temperatures). The
aim of this proposal is to use infrared recombination lines of Hydrogen
and Helium, as well as forbidden lines, to study the velocity field in
Be star discs.
Infrared spectroscopy of these discs has several advantadges over
optical data. The IR lines are much easier to model than the
optical Balmer or Paschen lines. Furthermore the IR lines have only weak
photospheric components and so the correction for the underlying
photospheric absorption lines introduces much less uncertainty in the
emission contribution from the disc.
Infrared recombination line widths depend strongly on the details of the
velocity law (both rotational and radial) as a function of distance.
The ISO grating spectrometer has sufficient resolution to determine the
width of the lines (FWHM) as a function of wavelength and line strength,
and so will allow us to map especially the rotational velocity field.
Nothing is known about this rotational velocity field. Recent
observations indicate that some discs rotate faster than the underlying
star. If this is the case, some mechanism (possibly magnetic fields) may
be responsible for spinning up these discs.
The line strengths are sensitive probes of the density structure, both
in the radial and in the vertical direction. In order to have sufficient
constraints on models, it is important to observe many lines over a
wide wavelength range and optical depth range,
i.e. SWS is the ideal instrument to obtain such spectra.
We also propose to investigate the high-level IR Hydrogen recombination
lines in 'normal' B stars. Model calculations suggest that these lines
are very senstive to the presence of small amounts of circumstellar gas,
or to deviations from classical LTE model atmospheres. The recent
discovery of Bralpha emission in tau Sco illustrates that normal
B stars can have infrared Hydrogen recombination lines without having
Balmer emission lines. Since the high-level HI recombination lines are
not observable from the ground, SWS observations are the only way to
obtain this information. These observations will therefore allow us to study
mass loss in main sequence B stars, of which nothing is known at present.
OBSERVATION SUMMARY.
We propose to observe HI and HeI recombination lines and forbidden line
transitions in the Be stars listed in the tables below, using the SWS in
the grating mode (AOT02). We have selected a range of line strengths and
optical depths to probe the circumstellar disc. In addition we request
a PHT-S spectrum for all targets. For Gamma Cas we request a full SWS
scan at reduced resolution (AOT01).
We plan to observe the following lines with SWS AOT02:
[Fe II] 5.34
[Ni II] 6.62
[Fe III] 22.94
[Fe II] 25.97
Br Alfa 4.05
Pf Alfa 7.46
Hu Bet 7.50
Hu Alfa 12.36
HI 10-7 8.76
HI 9-7 11.31
HI 8-7 19.05
HI 11-9 22.94
He I 4.03
He I 4.60
He I 23.04
<=== scientific_justification ===>
Time distribution for spring launch targets
Team: top 40% second 30% last 30%
SWS: 7524 12024 5496
Time distribution for autumn launch targets
Team: top 40% second 30% last 30%
SWS: 7524 8718 9696
Table 1. Cross-references source names
--------------------------------------------------------------------------
name 1 name 2 name 3 name4
1 Gamma Cas HR 264 B0.5 IVe
2 Delta Cen HR 4621 B2 IVpe
3 Psi Per HR 1087 B5 IIIe
4 Zeta Tau HR 1910 B4 IIIpe
5 Beta CMi HR 2845 B8 Ve
6 Eta Cen HR 5440 B1.5 Vne
7 Chi Oph HR 6118 B2 IV:pe
8 Alf Ara HR 6510 B2 Vne
9 Alf Eri HR 472 B3 Ve
10 Phi Per HR 496 B2 Vep
11 Eta Tau HR 1165 B7 IIIe
12 48 Per HR 1273 B3 Ve
13 Kap CMa HR 2538 B1.5 Vne
14 Omi Pup HR 3034 B0 V:pe:
15 48 Lib HR 5941 B5 IIIpe
16 Zet Oph HR 6175 O9.5Vne
17 EW Lac HR 8731 B4 IIIep
.........................................................................
18 Eps Per HR 1220 B0.5 V
19 Gam Ori HR 1790 B2 III
20 Delta Ori HR 1852 B0 III
21 Alf Leo HR 3982 B7 V
22 Alf Cru HR 4730 B0.5 IV
23 Bet Cru HR 4853 B0.5 III
24 Alf Vir HR 5056 B1 III-IV
25 Eta UMa HR 5191 B3 V
26 Bet Cen HR 5267 B1 III
27 Del Sco HR 5953 B0.3 IV
28 Tau Sco HR 6165 B0.2 V
29 Lam Sco HR 6527 B2 IV
--------------------------------------------------------------------------
Table 2. Positions and offsets
--------------------------------------------------------------------------
No ra dec precision offset ref pos window
2000.0 (",") (",")
1 00 56 42.4 +60 43 00 1,1 0,0 1 safe
2 12 08 21.5 -50 43 20 1,1 0,0 1 safe
3 03 36 29.3 +48 11 34 1,1 0,0 1 spr
4 05 37 38.6 +21 08 33 1,1 0,0 1 spr
5 07 27 09.0 +08 17 21 1,1 0,0 1 spr
6 14 35 30.3 -42 09 28 1,1 0,0 1 aut
7 16 27 01.3 -18 27 23 1,1 0,0 1 aut
8 17 31 50.4 -49 52 34 1,1 0,0 1 aut
9 01 37 42.9 -57 14 12 1,1 0,0 1 saf
10 01 43 39.6 +50 41 20 1,1 0,0 1 saf
11 03 47 29.0 +24 06 18 1,1 0,0 1 spr
12 04 08 39.6 +47 42 45 1,1 0,0 1 spr
13 06 49 50.4 -32 30 31 1,1 0,0 1 spr
14 07 48 05.1 -25 56 14 1,1 0,0 1 spr
15 15 58 11.3 -14 16 46 1,1 0,0 1 aut
16 16 37 09.4 -10 34 02 1,1 0,0 1 aut
17 22 57 04.5 +48 41 03 1,1 0,0 1 saf
.........................................................................
18 03 57 51.2 +40 00 37 1,1 0,0 1 spr
19 05 25 07.8 +06 20 59 1,1 0,0 1 spr
20 05 32 00.3 -00 17 57 1,1 0,0 1 spr
21 10 08 22.3 +11 58 02 1,1 0,0 1 spr
22 12 26 35.9 -63 05 56 1,1 0,0 1 aut
23 12 47 43.3 -59 41 19 1,1 0,0 1 aut
24 13 25 11.5 -11 09 41 1,1 0,0 1 aut
25 13 47 32.3 +49 18 48 1,1 0,0 1 aut
26 14 03 49.4 -60 22 22 1,1 0,0 1 aut
27 16 00 19.9 -22 37 18 1,1 0,0 1 aut
28 16 35 52.9 -28 12 58 1,1 0,0 1 aut
29 17 33 36.4 -37 06 13 1,1 0,0 1 aut
--------------------------------------------------------------------------
References for positions:
1. Hoffleit and Jaschek: The Bright Star Catalogue.
Table 4. Photometric data (fluxes in Jy)
--------------------------------------------------------------------------
# Star name J H K L M 12 25 60
===========================================================================
1 Gamma cas 196.6 138.5 100.7 56.8 44.7 14.7 6.73 2.17
2 Delta cen 136.0 97.6 67.1 39.6 26.2 12.6 7.11 2.94
3 Psi per 31.2 21.9 16.1 8.68 6.84 3.25 1.80 0.79
4 Zeta tau 81.9 61.0 42.0 23.7 17.7 6.50 3.11 0.99
5 Beta cmi 103.2 62.7 42.3 18.8 12.3 3.21 1.52 0.59
6 Eta cen 118.4 75.4 40.4 17.3 10.5 4.25 1.45 0.45
7 Chi oph 71.4 58.3 46.9 26.2 17.3 8.91 4.51 2.28
8 Alf ara 95.8 68.8 48.2 29.8 - 10.1 5.07 1.68
9 Alf eri 783 503 298 128 74.3 11.2 2.81 0.51
10 Phi per 43.8 32.3 25.3 16.1 - 6.1 3.11 1.05
11 Eta tau 95.8 62.1 38.6 17.9 9.8
12 48 per 42.6 28.9 19.9 10.4 - 3.06 1.80 0.79
13 Kap cma 58.8 40.7 28.0 15.8 10.8 5.16 2.46 0.79
14 Omi pup 28.7 21.2 15.4 9.0 6.1 1.99 0.74 -
15 The crb 27.9 17.6 10.7 4.7 2.6
16 48 lib 17.8 12.4 8.6 4.0 3.1 1.42 0.53 -
17 Zet oph 150.5 97.6 59.5 23.0 -
18 EW Lac 11.3 7.8 5.3 2.7 2.0 1.41 0.91 -
...........................................................................
19 Eps Per 73.4 - 26.5 10.6 - 1.5 0.4 -
20 Gam Ori 219.5 133.5 77.1 31.8 18.7 4.7 1.2 -
21 Delta Ori 137.3 79.7 47.3 19.7 10.8 - - -
22 Alf Leo 388.6 247.4 150.9 64.0 36.4 9.5 2.1 -
23 Alf Cru - - - - - 9.1 2.3 -
24 Bet Cru 311.5 186.0 106.4 41.5 - - - -
25 Alf Vir 392.2 252.0 142.8 57.9 32.4 8.9 1.8 -
26 Eta UMa 202.1 - 72.9 32.1 18.8 4.2 1.0 -
27 Bet Cen - - - - - 11.4 2.3 -
28 Del Sco 143.7 98.5 56.3 23.0 13.0 3.4 0.8 -
29 Tau Sco 72.0 43.0 24.3 9.8 5.5 1.3 - -
30 Lam Sco - - - - - 4.4 1.2 -
===========================================================================
Table 5. Priorities, Time and Coordination with other consortia.
--------------------------------------------------------------------------
Additional observations
No ident prio AOT time LWS CAM PHT in SWS time needed:
(secs)
--------------------------------------------------------------------------
1 Gamma Cas 1 SWS02 1332 + PHT-S
SWS01 3600
2 PHT40 120
2 PHT22 300
2 Delta Cen 1 SWS02 1332 PHT-S
PHT40 120
2 PHT22 300
3 Psi Per 1 SWS02 1140 PHT-S
3 PHT40 120
3 PHT22 300
4 Zeta Tau 2 SWS02 1140 PHT-S
PHT40 120
5 Beta CMi 2 SWS02 1236 PHT-S
PHT40 120
6 Eta Cen 3 SWS02 1428 PHT-S
PHT40 120
7 Chi Oph 3 SWS02 1332 PHT-S
PHT40 120
8 Alf Ara 2 SWS02 1332 PHT-S
PHT40 120
9 Alf Eri 2 SWS02 1140 PHT-S
PHT40 120
10 Phi Per 3 SWS02 1332 PHT-S
PHT40 120
11 Eta Tau 2 SWS02 1140 PHT-S
PHT40 120
12 48 Per 3 SWS02 1140 PHT-S
PHT40 120
13 Kap CMa 2 SWS02 1332 PHT-S
PHT40 120
14 Omi Pup 2 SWS02 1908 PHT-S
PHT40 120
15 48 Lib 2 SWS02 1542 PHT-S
PHT40 120
16 Zet Oph 3 SWS02 1332 PHT-S
PHT40 120
17 EW Lac 2 SWS02 1524 PHT-S
PHT40 120
18 Eps Per 2 SWS02 1044 PHT-S
3 PHT40 120
19 Gam Ori 3 SWS02 564 PHT-S
3 PHT40 120
20 Delta Ori 3 SWS02 660 PHT-S
3 PHT40 120
21 Alf Leo 3 SWS02 660 PHT-S
3 PHT40 120
22 Alf Cru 2 SWS02 660 PHT-S
3 PHT40 120
23 Bet Cru 3 SWS02 660 PHT-S
3 PHT40 120
24 Alf Vir 3 SWS02 660 PHT-S
3 PHT40 120
25 Eta UMa 3 SWS02 660 PHT-S
3 PHT40 120
26 Bet Cen 2 SWS02 660 PHT-S
3 PHT40 120
27 Del Sco 2 SWS02 660 PHT-S
3 PHT40 120
28 Tau Sco 1 SWS02 1140 PHT-S
3 PHT40 120
29 Lam Sco 3 SWS02 852 PHT-S
3 PHT40 120
--------------------------------------------------------------------------
<=== autumn_launch_targets ===>
1, "SWS02", 1.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 1332, 2
2, "SWS01", 1.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 3600, 3
3, "PHT40", 2.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 120, 4
4, "PHT22", 2.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 300, 0
5, "SWS02", 1.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 1332, 6
6, "PHT40", 1.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 120, 7
7, "PHT22", 2.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 300, 0
8, "SWS02", 3.,"N", "Eta Cen ", 14.59175, -42.15778, 2000, 0.,0., 1428, 9
9, "PHT40", 3.,"N", "Eta Cen ", 14.59175, -42.15778, 2000, 0.,0., 120, 0
10, "SWS02", 3.,"N", "Chi Oph ", 16.45036, -18.45639, 2000, 0.,0., 1332, 11
11, "PHT40", 3.,"N", "Chi Oph ", 16.45036, -18.45639, 2000, 0.,0., 120, 0
12, "SWS02", 2.,"N", "Alf Ara ", 17.53067, -49.87611, 2000, 0.,0., 1332, 13
13, "PHT40", 2.,"N", "Alf Ara ", 17.53067, -49.87611, 2000, 0.,0., 120, 0
14, "SWS02", 2.,"N", "Alf Eri ", 1.62858, -57.23667, 2000, 0.,0., 1140, 15
15, "PHT40", 2.,"N", "Alf Eri ", 1.62858, -57.23667, 2000, 0.,0., 120, 0
16, "SWS02", 3.,"N", "Phi Per ", 1.72767, 50.68889, 2000, 0.,0., 1332, 17
17, "PHT40", 3.,"N", "Phi Per ", 1.72767, 50.68889, 2000, 0.,0., 120, 0
18, "SWS02", 2.,"N", "48 Lib ", 15.96981, -14.27944, 2000, 0.,0., 1542, 19
19, "PHT40", 2.,"N", "48 Lib ", 15.96981, -14.27944, 2000, 0.,0., 120, 0
20, "SWS02", 3.,"N", "Zet Oph ", 16.61928, -10.56722, 2000, 0.,0., 1332, 21
21, "PHT40", 3.,"N", "Zet Oph ", 16.61928, -10.56722, 2000, 0.,0., 120, 0
22, "SWS02", 2.,"N", "EW Lac ", 22.95125, 48.68417, 2000, 0.,0., 1524, 23
23, "PHT40", 2.,"N", "EW Lac ", 22.95125, 48.68417, 2000, 0.,0., 120, 0
24, "SWS02", 2.,"N", "Alf Cru ", 12.44331, -63.09889, 2000, 0.,0., 660, 25
25, "PHT40", 3.,"N", "Alf Cru ", 12.44331, -63.09889, 2000, 0.,0., 120, 0
26, "SWS02", 3.,"N", "Bet Cru ", 12.79536, -59.68861, 2000, 0.,0., 660, 27
27, "PHT40", 3.,"N", "Bet Cru ", 12.79536, -59.68861, 2000, 0.,0., 120, 0
28, "SWS02", 3.,"N", "Alf Vir ", 13.41986, -11.16139, 2000, 0.,0., 660, 29
29, "PHT40", 3.,"N", "Alf Vir ", 13.41986, -11.16139, 2000, 0.,0., 120, 0
30, "SWS02", 3.,"N", "Eta UMa ", 13.79231, 49.31333, 2000, 0.,0., 660, 31
31, "PHT40", 3.,"N", "Eta UMa ", 13.79231, 49.31333, 2000, 0.,0., 120, 0
32, "SWS02", 2.,"N", "Bet Cen ", 14.06372, -60.37278, 2000, 0.,0., 660, 33
33, "PHT40", 3.,"N", "Bet Cen ", 14.06372, -60.37278, 2000, 0.,0., 120, 0
34, "SWS02", 2.,"N", "Del Sco ", 16.00553, -22.62167, 2000, 0.,0., 660, 35
35, "PHT40", 3.,"N", "Del Sco ", 16.00553, -22.62167, 2000, 0.,0., 120, 0
36, "SWS02", 1.,"N", "Tau Sco ", 16.59803, -28.21611, 2000, 0.,0., 1140, 37
37, "PHT40", 3.,"N", "Tau Sco ", 16.59803, -28.21611, 2000, 0.,0., 120, 0
38, "SWS02", 3.,"N", "Lam Sco ", 17.56011, -37.10361, 2000, 0.,0., 852, 39
39, "PHT40", 3.,"N", "Lam Sco ", 17.56011, -37.10361, 2000, 0.,0., 120, 0
<=== spring_launch_targets ===>
1, "SWS02", 1.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 1332, 2
2, "SWS01", 1.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 3600, 3
3, "PHT40", 2.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 120, 4
4, "PHT22", 2.,"N", "Gamma Cas ", 0.94511, 60.71667, 2000, 0.,0., 300, 0
5, "SWS02", 1.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 1332, 6
6, "PHT40", 1.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 120, 7
7, "PHT22", 2.,"N", "Delta Cen ", 12.13931, -50.72222, 2000, 0.,0., 300, 0
8, "SWS02", 1.,"N", "Psi Per ", 3.60814, 48.19278, 2000, 0.,0., 1140, 9
9, "PHT40", 3.,"N", "Psi Per ", 3.60814, 48.19278, 2000, 0.,0., 120, 10
10, "PHT22", 3.,"N", "Psi Per ", 3.60814, 48.19278, 2000, 0.,0., 300, 0
11, "SWS02", 2.,"N", "Zeta Tau ", 5.62739, 21.14250, 2000, 0.,0., 1140, 12
12, "PHT40", 2.,"N", "Zeta Tau ", 5.62739, 21.14250, 2000, 0.,0., 120, 0
13, "SWS02", 2.,"N", "Beta CMi ", 7.45250, 8.28917, 2000, 0.,0., 1236, 14
14, "PHT40", 2.,"N", "Beta CMi ", 7.45250, 8.28917, 2000, 0.,0., 120, 0
15, "SWS02", 2.,"N", "Alf Eri ", 1.62858, -57.23667, 2000, 0.,0., 1140, 16
16, "PHT40", 2.,"N", "Alf Eri ", 1.62858, -57.23667, 2000, 0.,0., 120, 0
17, "SWS02", 3.,"N", "Phi Per ", 1.72767, 50.68889, 2000, 0.,0., 1332, 18
18, "PHT40", 3.,"N", "Phi Per ", 1.72767, 50.68889, 2000, 0.,0., 120, 0
19, "SWS02", 2.,"N", "Eta Tau ", 3.79139, 24.10500, 2000, 0.,0., 1140, 20
20, "PHT40", 2.,"N", "Eta Tau ", 3.79139, 24.10500, 2000, 0.,0., 120, 0
21, "SWS02", 3.,"N", "48 Per ", 4.14433, 47.71250, 2000, 0.,0., 1140, 22
22, "PHT40", 3.,"N", "48 Per ", 4.14433, 47.71250, 2000, 0.,0., 120, 0
23, "SWS02", 2.,"N", "Kap CMa ", 6.83067, -32.50861, 2000, 0.,0., 1332, 24
24, "PHT40", 2.,"N", "Kap CMa ", 6.83067, -32.50861, 2000, 0.,0., 120, 0
25, "SWS02", 2.,"N", "Omi Pup ", 7.80142, -25.93722, 2000, 0.,0., 1908, 26
26, "PHT40", 2.,"N", "Omi Pup ", 7.80142, -25.93722, 2000, 0.,0., 120, 0
27, "SWS02", 2.,"N", "EW Lac ", 22.95125, 48.68417, 2000, 0.,0., 1524, 28
28, "PHT40", 2.,"N", "EW Lac ", 22.95125, 48.68417, 2000, 0.,0., 120, 0
29, "SWS02", 2.,"N", "Eps Per ", 3.96422, 40.01028, 2000, 0.,0., 1044, 30
30, "PHT40", 3.,"N", "Eps Per ", 3.96422, 40.01028, 2000, 0.,0., 120, 0
31, "SWS02", 3.,"N", "Gam Ori ", 5.41883, 6.34972, 2000, 0.,0., 564, 32
32, "PHT40", 3.,"N", "Gam Ori ", 5.41883, 6.34972, 2000, 0.,0., 120, 0
33, "SWS02", 3.,"N", "Delta Ori ", 5.53342, -0.29917, 2000, 0.,0., 660, 34
34, "PHT40", 3.,"N", "Delta Ori ", 5.53342, -0.29917, 2000, 0.,0., 120, 0
35, "SWS02", 3.,"N", "Alf Leo ", 10.13953, 11.96722, 2000, 0.,0., 660, 36
36, "PHT40", 3.,"N", "Alf Leo ", 10.13953, 11.96722, 2000, 0.,0., 120, 0