7758( 11) - 05/26/99 07:36 - [ 1] PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID: 7758 Version: 11 Check-in Date: 26-May-1999 07:36:18 1.Proposal Title: Physics of diffuse clouds in the Local Bubble , Part I : the CMa tunnel ------------------------------------------------------------------------------------ 2. Proposal For 3. Cycle GO/CAR 7 ------------------------------------------------------------------------------------ 4. Investigators Contact? PI: Cecile Gry Laboratoire d'Astronomie Spatiale CoI: Don Cox University of Wisconsin-Madison N CoI: Roger Ferlet Institut d'Astrophysique de Paris N CoI: Martin Lemoine Institut d'Astrophysique de Paris N CoI: Alfred VidalMadjar Institut d'Astrophysique de Paris N ------------------------------------------------------------------------------------ 5. Abstract We propose to study the physical conditions in diffuse clouds in the Local Bubble environment and their interfaces with the hot gas filling the bubble. , The local interstellar medium presents a favourable situation to check the general ISM theories. Particularly helpfull are lines of sight with low column densities and few or well separated velocity components, which are resolved at a resolution of 10^5., These include nearby white dwarfs which will be better observed in cycle 7 with STIS, and a few early-type stars in the particularly empty direction of Canis Majoris, which present the advantage of a long pathlength through the hot bubble gas. These stars will on the contrary be observed much more efficiently with GHRS, for which cycle 6 presents the last opportunity., The main questions that high resolution UV spectroscopy will allow to address are :, - the characterisation of the interface between diffuse clouds and the hot bubble gas., - the ionization state and the depletion level in the local environment., - the nature of the various different velocity components found in a small volume around the sun., ------------------------------------------------------------------------------------ 7758( 11) - 05/26/99 07:36 - [ 2] Observations Description ------------------------ Note on the importance of cycle 6. We want to stress that it is important to observe our early-type stars with GHRS in this cycle by concern for efficiency. Indeed they are all very bright and will therefore be very difficult to observe with STIS which does not allow high count rates and require the use of a filter, increasing substantially the observing time. As an example for Beta CMa the global count rate is a factor 50 above the limiting count number. Inversely, in this cycle we do not ask time for the second part of the program making use of nearby white dwarfs which will be much more efficiently done with STIS., Acquisition, All targets are bright and require acquisition with the A2 mirror (20 min). We will perform all observations with the SSA to get the maximum resolution (17 min extra acquisition time). Thus with the first guide star acquisition (8 min), it takes already 45 min per star for aquisition purposes only (out of a visibility period of 53 min). , For each following orbit 6 min are necessary for guide star re-acquisition, thus 47 min are available. , Science exposures., For all the goals described above, we need high resolution (~ 3 km/s) Echelle observations to resolve the individual components separated by a few km/s in order to derive the characteristics of each component separately. The following ECH-A settings are required : , order 47 1192 Angstrom : SIII 1190.208, SiII 1190.416, SiII 1193.290, order 47 1200 Angstrom : NI 1199.550, NI 1200.223, NI 1200.710, order 47 1206 Angstrom : SiIII 1206.500, order 46 1215 Angstrom : HI 1215.67, DI 1215.34, order 45 1240 Angstrom : NV 1238.821, NV1242.804, order 45 1251 Angstrom : SII 1250.584, SII 1253.811, order 45 1259 Angstrom : SII 1259.519, SiII 1260.422, order 43 1303 Angstrom : OI 1302.168, SiII 1304.370, order 42 1335 Angstrom : CII 1334.532, CII* 1335.70, order 40 1394 Angstrom : SiIV 1393.755, order 40 1402 Angstrom : SiIV 1402.770, order 36 1550 Angstrom : CIV 1548.195, CIV 1550.770, For the 3 never observed stars (Lambda, Zeta and Kappa CMa) we ask for 3 additional ECH-B settings :, order 20 2800Angstrom : MgII 2796.352, MgII 2803.531, order 24 2378Angstrom : FeII 2374.461, FeII 2382.765, order 20 2853Angstrom : MgI 2852.964, We will use the FP-SPLIT=4 and four samples per diode., To calculate exposure times, we use the sensitivity and blaze functions given in the GHRS Instrument Handbook version 6 and we estimate the fluxes from previous low resolution spectra when they exist or by combining TD1 measurements with IUE standard stars spectra., Following are two examples for Kappa CMa : , Ech A. At 1200 Angstrom (NI lines) F_Lambda = 3.5 10^-9 erg /s.cm^2.Angstrom , S_Lambda = .38 10^11 Cnts diode^-1 s^-1 (erg/s.cm^2.Angstrom )^-1; Blaze factor = 0.95 ; SSA factor = 0.5, Count number per 1/4 diode = 1/4 .18 10^11 F_Lambda = 15.7 s^ -1. A S/N of 60 per 1/4 diode is thus obtained in 230 s., Ech B. At 2800 Angstrom (MgII lines) F_Lambda = 8.6 10^-10 erg /s.cm^2.Angstrom , S_Lambda = 13.86 10^11 Cnts diode^-1 s^-1 (erg/s.cm^2.Angstrom )^-1; Blaze factor = 0.95; SSA factor = 0.6, Count number per 1/4 diode = 1/4 7.9 10^11 F_Lambda = 170 s^- 1. A S/N of 60 per 1/4 diode is thus obtained in 21 s., In general the exposure times are short and the total time is dominated by the overheads (4 min). , A few WAVE exposures are desirable to know precisely the wavelength scale zero- point and ensure that all components are identified correctly. We will ask one WAVE for a setting covering both neutral and ionised species lines (order 43), and one for one setting covering highly ionized species like CIV. The other settings will be aligned on those two with the help of the interstellar components. This adds 6 min per star., Target list giving the total exposure time for each star (including overheads and WAVE) beginflushleft begintabularllllllll star name & HD & d (pc) & type & M_v & cont. 1200 Angstrom & cont. 2800 Angstrom & expo time , Beta CMa & 44743 & 203 & B1 II-III & 1.97 & 2.4 10^-8 & & 1.3 orbit, Epsilon CMa & 52089 & 187 & B2 II & 1.50 & 2.5 10^-8 & & 1.3 orbit, Zeta CMa & 44402 & 102 & B2.5 V & 3.02 & 4.9 10^-9 & 9.0 10^-10 & 1.6 orbit, Kappa CMa & 50013 & 298 & B2 Ve & 3.96 & 3.5 10^-9 & 6.5 10^-10 & 2.3 orbits, Lambda CMa & 45813 & 131 & B4 V & 4.5 & 1 10^-9 & 1.9 10^-10 & 3.9 orbits, Alpha CMa & 48915 & 2.7 & A0 V & -1.5 & 1 10^-10 & & 2.9 orbits, endtabular endflushleft We thus need 16 orbits for the science exposures of the six stars, to which have to be added the 6 acquisition orbits. Real Time Justification ----------------------- Calibration Justification ------------------------- Additional Comments ------------------- ------------------------------------------------------------------------------------ 7758( 11) - 05/26/99 07:36 - [ 3] Data Distribution Paper Products: Media: ELECTRONIC Blocking Factor: 10 Ship To: PI_Address Ship Via: Email: ------------------------------------------------------------------------------------ 7758( 11) - 05/26/99 07:36 - [ 4] TARGET LIST a) Fixed Targets ------------------------------------------------------------------------------------------------------------------------------------ Tar| Target | Target | Target |Coord | Radial | Flux data No | Name | Description | Position |Eqnx | Vel. | ------------------------------------------------------------------------------------------------------------------------------------ 1 REJ0503-289 STAR, WDO RA=05H03M55.38S+/-0.3", DEC=- J2000 V = 13.95+/-0.05 28D54'36.5"+/-0.3", PLATE- TYPE=DO ID=04WB F-CONT(1200)=2.2+/-0.05e-12 F-CONT(1250)=2.1+/-0.05e-12 F-CONT(1550)=1.0+/-0.2e-12 2 HD44743 STAR, B0-B2 III-I RA=06H22M41.98740S+/-0.003S, J2000 V = 1.98+/-0.01 DEC=-17D57'21.2997"+/-0.04" TYPE=B1II B-V = -0.23+/-0.01 F-CONT(1200)=4+/-0.25e-8 F-CONT(1550)=1.37+/-0.25e-8 F-CONT(1650)=2+/-0.25e-8 Comments: Coordinates, parallax and proper motion from Hipparcos. Epoch of Position RA proper motion (seconds of time/yr) DEC Proper Motion (arcsec/yr) Annual Parallax (arcsec) J2000 -0.00345 -0.00047 0.00653 7758( 11) - 05/26/99 07:36 - [ 5] Visit: 01 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 11 REJ0503-289 STIS/C ACQ F28X50L MIRROR 1 0.2 S ONBOARD ACQ FOR 12 CD P ------------------------------------------------------------------------------------------------------------------------------------ 12 REJ0503-289 STIS/C ACQ/PEA 0.2X0.0 MIRROR 1 0.5 S ONBOARD ACQ FOR 13-14 CD K 9 ------------------------------------------------------------------------------------------------------------------------------------ 13 REJ0503-289 STIS/F ACCUM 0.2X0.0 E140H 1271 1 35 M UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 14 REJ0503-289 STIS/F ACCUM 0.2X0.0 E140H 1271 3 48 M UV-MAM 9 A ------------------------------------------------------------------------------------------------------------------------------------ 7758( 11) - 05/26/99 07:36 - [ 6] Visit: 51 Visit Priority: Visit Requirements: On Hold Comments: Additional Comments: Exposures ------------------------------------------------------------------------------------------------------------------------------------ Exposure| Target |Instr | Oper. | Aper |Spectral|Central| Optional |Num| Time | Special Number | Name |Config| Mode |or FOV |Element |Waveln.| Parameters |Exp| | Requirements ------------------------------------------------------------------------------------------------------------------------------------ 21 HD44743 STIS/C ACQ F25ND5 MIRROR 1 0.2 S ONBOARD ACQ FOR 22 CD ------------------------------------------------------------------------------------------------------------------------------------ 22 HD44743 STIS/C ACQ/PEA 0.2X0.0 G230MB 2276 1 0.5 S ONBOARD ACQ FOR 23-24 CD K 5ND ------------------------------------------------------------------------------------------------------------------------------------ 23 HD44743 STIS/F ACCUM 0.3X0.0 E140H 1271 5 23 M UV-MAM 5ND A ------------------------------------------------------------------------------------------------------------------------------------ 24 HD44743 STIS/F ACCUM 0.2X0.0 E140H 1598 3 14 M UV-MAM 5ND A ------------------------------------------------------------------------------------------------------------------------------------ 7758( 11) - 05/26/99 07:36 - [ 7] Summary Form for Proposal 7758 Item Used in this proposal ------------------------------------------------------------------------------------------------------------------------------------ Apertures F28X50LP 0.2X0.09 F25ND5 0.2X0.05ND 0.3X0.05ND ------------------------------------------------------------------------------------------------------------------------------------ Configurations STIS/CCD STIS/FUV-MAMA ------------------------------------------------------------------------------------------------------------------------------------ Opmodes ACQ ACQ/PEAK ACCUM ------------------------------------------------------------------------------------------------------------------------------------ Proposal Category GO/CAR ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements ONBOARD ACQ FOR 12 ONBOARD ACQ FOR 13-14 ONBOARD ACQ FOR 22 ONBOARD ACQ FOR 23-24 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements MIRROR E140H G230MB ------------------------------------------------------------------------------------------------------------------------------------ Target Names REJ0503-289 HD44743 ------------------------------------------------------------------------------------------------------------------------------------ Wavelengths 1271 2276 1598 ------------------------------------------------------------------------------------------------------------------------------------