! File: 4677C.PROP
! Database: PEPDB
! Date: 22-FEB-1994:22:07:43
coverpage:
title_1: A SENSITIVE SEARCH FOR HIGH-VELOCITY GAS IN THE OUTER GALACTIC HALO
title_2: -CYC3
sci_cat: INTERSTELLAR MEDIUM
sci_subcat: ABSORPTION LINES
proposal_for: GO
pi_fname: DAVID
pi_mi: M.
pi_lname: MEYER
pi_inst: NORTHWESTERN UNIVERSITY
pi_country: USA
hours_pri: 2.02
num_pri: 3
hrs: Y
funds_length: 24
off_fname: WILLIAM
off_mi: J.
off_lname: GEALY
off_title: DIRECTOR
off_inst: 3020
off_addr_1: OFFICE OF RESEARCH AND SPONSORED PROGRAMS
off_addr_2: NORTHWESTERN UNIVERSITY
off_addr_3: 633 CLARK STREET
off_city: EVANSTON
off_state: IL
off_zip: 60208
off_country: USA
off_phone: 708-491-3003
! end of coverpage
abstract:
line_1: We propose to obtain observations of the Mg II absorption toward a sample of
line_2: eight bright Seyfert galaxies and BL Lac objects with the GHRS on HST in an
line_3: effort to search for the metal-line counterparts of high-velocity H I clouds
line_4: (HVCs) over pathlengths which cover the full extent of the Galactic halo.
line_5: Based on a statistical extrapolation beyond the 10e18 cm-2 sensitivity of
line_6: recent H I 21 cm emission surveys, Wakker (1991) has estimated that HVCs with
line_7: N(H I)>2x10e17 cm-2 cover somewhere between 30% and 60% of the sky. Such a
line_8: limiting column density of high-velocity gas would be detectable in Mg II
line_9: absorption against bright extragalactic targets with GHRS provided that the gas
line_10: is not too metal-poor (<0.1 solar). The lack of such high-velocity absorption
line_11: toward Danly's (1989) IUE sample of bright halo stars has led Wakker to
line_12: conclude that, in general, HVCs are located at large distances beyond the
line_13: inner Galactic halo. With the exception of the Magellanic Cloud and 3C 273
line_14: sightlines, previous UV and optical absorption-line studies of halo gas toward
line_15: extragalactic targets have not had the sensitivity to detect low N(H I) HVCs.
line_16: Thus, the primary goal of our Mg II survey is to determine if such HVCs are a
line_17: common constituent of the Galactic halo. Our results will also have an impact
line_18: on the question of metallicity in HVCs. Furthermore, if we find ubiquitous
line_19: high-velocity Mg II absorption, it would provide new support for the idea that
line_20: at least some QSO absorbers are due to the halos of intervening galaxies.
!
! end of abstract
general_form_proposers:
lname: MEYER
fname: DAVID
title: PI
mi: M.
inst: NORTHWESTERN UNIVERSITY
country: USA
esa: N
!
lname: SAVAGE
fname: BLAIR
mi: D.
inst: UNIVERSITY OF WISCONSIN
country: USA
esa: N
!
lname: LU
fname: LIMIN
inst: UNIVERSITY OF WISCONSIN
country: USA
esa: N
!
! end of general_form_proposers block
general_form_text:
question: 3
section: 1
line_1: We propose to use the GHRS on HST to measure the veloctiy structure
line_2: of the MG II absorptionline profiles through the Galactic halo
line_3: toward the sample of Seyfert galaxies listed above. The primary
line_4: selection criteria in choosing these extragalactic targets is their
line_5: comparative UV brightness. They represent a reasonably well-distributed
line_6: range of sightliness throught the halo with the H I 21 cm surveys
line_7: indicating the presence of known high-velocity clouds (HVs) toward
line_8: Fairall 9 and NGC 3783. At the LSA-degraded GHRS G270M resolution
line_9: of R=10,000, we will be able to easily spearte any HVC (v>100 km/sec)
line_10: MG II absorption from that of local disk gas. The enhanced throughput
line_11: of the LSA and the optimal sensitivity of the GHRS near 2800 A will
line_12: allow us to efficiently achieve 5 sigma detections of 100 mA MG II
line_13: 2796 A features toward each of our targets. Assuming solar abundances,
line_14: this threshold in MG II should enable us to detect NVCs in absorption
line_15: at a level over an order of magnitude better than the H I 21 cm surveys.
!
!end of general form text
general_form_address:
lname: Meyer
fname: David
mi: M.
category: PI
inst: Northwestern University
addr_1: Department of Physics and Astronomy
city: Evanston
state: IL
zip: 60208
country: USA
phone: 708-491-4516
!
! end of general_form_address records
fixed_targets:
targnum: 1
name_1: FAIRALL9
descr_1: E,312
pos_1: RA=1H23M45.7S+/-0.1S,
pos_2: DEC=-58D48'22"+/-1"
equinox: 2000
pm_or_par: NO
rv_or_z: Z=0.045
fluxnum_1: 1
fluxval_1: V=13.2
fluxnum_2: 2
fluxval_2: F-CONT(2800)=2.5E-14
!
targnum: 2
name_1: AKN120
descr_1: E,312
pos_1: RA=5H16M11.4S+/-0.1S,
pos_2: DEC=-0D8'59"+/-1"
equinox: 2000
pm_or_par: NO
rv_or_z: Z=0.033
fluxnum_1: 1
fluxval_1: V=13.9
fluxnum_2: 2
fluxval_2: F-CONT(2800)=3.5E-14
!
targnum: 3
name_1: NGC3783
descr_1: E,312
pos_1: RA=11H39M1.8S+/-0.1S,
pos_2: DEC=-37D44'19"+/-1"
equinox: 2000
pm_or_par: NO
rv_or_z: Z=0.0096
fluxnum_1: 1
fluxval_1: V=13.4
fluxnum_2: 2
fluxval_2: F-CONT(2800)=3.0E-14
!
! end of fixed targets
! No solar system records found
! No generic target records found
exposure_logsheet:
linenum: 1.000
targname: FAIRALL9
config: HRS
opmode: ACQ
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 20.0S
fluxnum_1: 1
priority: 1
param_1: SEARCH-SIZE=5,
param_2: BRIGHT=RETURN,
req_1: CYCLE 3/1-3;
req_2: ONBOARD ACQ FOR 2
comment_1: STEP-TIME=0.8S
!
linenum: 2.000
targname: FAIRALL9
config: HRS
opmode: ACQ/PEAKUP
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 81.6S
fluxnum_1: 1
priority: 1
req_1: ONBOARD ACQ FOR 3
comment_1: STEP-TIME=0.8S
!
linenum: 3.000
targname: FAIRALL9
config: HRS
opmode: ACCUM
aperture: 2.0
sp_element: G270M
wavelength: 2808
num_exp: 3
time_per_exp: 15.6M
s_to_n: 15
s_to_n_time: 46.8M
fluxnum_1: 2
priority: 1
param_1: FP-SPLIT=STD
param_2: STEP-PATT=4
!
linenum: 4.000
targname: AKN120
config: HRS
opmode: ACQ
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 20.0S
fluxnum_1: 1
priority: 1
param_1: SEARCH-SIZE=5,
param_2: BRIGHT=RETURN,
req_1: CYCLE 3/4-6;
req_2: ONBOARD ACQ FOR 5
comment_1: STEP-TIME=0.8S
!
linenum: 5.000
targname: AKN120
config: HRS
opmode: ACQ/PEAKUP
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 81.6S
fluxnum_1: 1
priority: 1
req_1: ONBOARD ACQ FOR 6
comment_1: STEP-TIME=0.8S
!
linenum: 6.000
targname: AKN120
config: HRS
opmode: ACCUM
aperture: 2.0
sp_element: G270M
wavelength: 2808
num_exp: 2
time_per_exp: 18.0M
s_to_n: 15
s_to_n_time: 36.0M
fluxnum_1: 2
priority: 1
param_1: FP-SPLIT=STD
param_2: STEP-PATT=4
!
linenum: 7.000
targname: NGC3783
config: HRS
opmode: ACQ
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 20.0S
fluxnum_1: 1
priority: 1
param_1: SEARCH-SIZE=5,
param_2: BRIGHT=RETURN,
req_1: CYCLE 3/7-9;
req_2: ONBOARD ACQ FOR 8
comment_1: STEP-TIME=0.8S
!
linenum: 8.000
targname: NGC3783
config: HRS
opmode: ACQ/PEAKUP
aperture: 2.0
sp_element: MIRROR-N2
num_exp: 1
time_per_exp: 81.6S
fluxnum_1: 1
priority: 1
req_1: ONBOARD ACQ FOR 9
comment_1: STEP-TIME=0.8S
!
linenum: 9.000
targname: NGC3783
config: HRS
opmode: ACCUM
aperture: 2.0
sp_element: G270M
wavelength: 2808
num_exp: 2
time_per_exp: 19.2M
s_to_n: 15
s_to_n_time: 38.4M
fluxnum_1: 2
priority: 1
param_1: FP-SPLIT=STD
param_2: STEP-PATT=4
!
! end of exposure logsheet
! No scan data records found