Assigned ID: 553
----- Attempting Submission 1 (Fri Feb 24 18:29:30 GMT 2012) -----The submitted material has very minor adjustment of the coordinates of the target fields F6 and F9 with respect to those in the proposal. These adjustments were made to avoid
some brighter stars in the field. Also the roll angle for the target F7 was adjusted such that the visibility is improved, while still avoiding to have bright stars in the ACS parallel FOV.
Apart from that this is a straight forward imaging programme on the 5 target fields in the halo of NGC 5128. The primary instrument is WFC3 and it has coordinated paralles with ACS/WFC.----- Attempting Submission 1 (Thu Jun 28 22:44:03 GMT 2012) -----Probing the outermost halo in a giant galaxy: is it metal-poor and where does it end?Centaurus A (NGC 5128), the nearest gE/S0 galaxy is taking up an increasingly important role in stellar population and galaxy evolution studies with the potential to rival the Local Group members. From our previous HST-based studies of its red-giant population, we know that ~80% of its halo stars are old (11-13 Gyr), and relatively metal-rich ([Fe/H] ~ -0.5). In contrast, new measurements of the outer-halo of NGC 3379 (Leo group), and of M31 revealed the classically metal-poor component (as the Milky Way halo) at radii beyond R~10 R(eff) where the metal-rich stars disappear. This extremely extended "outermost halo" -- which has long been suspected to exist in giant galaxies but has been hard to isolate -- may be the evolutionary relic of the first stars formed in the extended dark-matter potential well of the galaxy at its earliest stages. This triggers the question whether such an extended halo also exists around NGC 5128 and what is its composition?
We propose to use WFC3 and ACS in parallel to probe the NGC 5128 halo to its outermost detectable limits beyond 15 effective radii, in search for its oldest, most metal-poor stars. Combined with our earlier HST work, which has sampled the metallicity distribution function (MDF) from 10 to 38 kpc (1.5-7 Reff), we will obtain a complete MDF profile extending from the outer bulge to the farthest limits of the halo. This study will be the first for any gE galaxy, and it will add entirely new constraints to understanding its formation history. We will be able to assess the relative importance of halo stars produced by protogalactic dwarfs at the beginning of hierarchical merging vs. late accretion from dwarf satellites.This is an imaging program with WFC3 and ACS/WFC in Coordinated Parallel mode on 5 target fields surveying the outer halo of NGC 5128. Each field is imaged in F814W and F606W filters. The parallel observations with ACS/WFC use the same filters and essentially augment the total field size. Very accurate pointing is not necessary and the orientation angle is set to avoid the bright stars in the ACS parallel, and could also be slightly more relaxed accepting some loss of area due to bright stars if necessary for scheduling. The two orbits for each target are placed within a visit in order to obtain the two filters for each pointing for the same field orientation.
Each field is imaged with 2 orbits, one orbit per filter. Within each orbit a set of 3 dithered observations using WFC3-UVIS-DITHER-LINE-3PT pattern are taken for each filter, for both primary and the parallel instrument in the same filter. The 3 primary (WFC3) exposures are packed within each orbit such that the overheads are minimized and the total exposure time maximized.RESOLVED STELLAR POPULATIONS12false0.00.0falsefalsefalsefalseSUPPORTEDGALAXYELLIPTICALHALORADIO GALAXYJ2000J2000V magnitude is tip of red-giant branch in NGC 5128GALAXYELLIPTICALHALORADIO GALAXYJ2000J2000GALAXYELLIPTICALHALORADIO GALAXYJ2000J2000GALAXYELLIPTICALHALORADIO GALAXYJ2000J2000GALAXYELLIPTICALHALORADIO GALAXYJ2000J2000WFC3/UVISImagingNoNoF814WWFC3/UVISImagingNoNoF606WACS/WFCImagingNoNoF814WACS/WFCImagingNoNoF606WWFC3/UVISImagingNoNoF814WWFC3/UVISImagingNoNoF606WACS/WFCImagingNoNoF814WACS/WFCImagingNoNoF606WWFC3/UVISImagingNoNoF814WWFC3/UVISImagingNoNoF606WACS/WFCImagingNoNoF814WACS/WFCImagingNoNoF606WWFC3/UVISImagingNoNoF814WWFC3/UVISImagingNoNoF606WACS/WFCImagingNoNoF814WACS/WFCImagingNoNoF606WWFC3/UVISImagingNoNoF814WWFC3/UVISImagingNoNoF606WACS/WFCImagingNoNoF814WACS/WFCImagingNoNoF606WPOS-TARGDITHER0.135LINEfalsefalse346.84WFC3-UVIS-DITHER-LINE-3PT3false/Users/mrejkuba/Work/proposals/HST_C20/N5128/Phase2/OP-cache/Phase2_HSTprop_12964-v01.xmlThe scheduling data was generated by CASM 20.2.CASM was run in Phase II mode.(Tic-Visit
:proposal-id 12964
:visit-id "01"
:proposal-version -1
:trans-version "20120604"
:date "24-Jun-2012 15:31:51.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 2
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 3437840
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 12964
:visit-id "01"
:obset-id "01"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12964
:visit-id "01"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2677
:al-overhead-at-end 115
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 12964
:visit-id "01"
:orbit-number 2
:pcs-time 222
:si-vis-utilization 2788
:al-overhead-at-end 115
:internal-dur-at-end 1015
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)true20/Users/mrejkuba/Work/proposals/HST_C20/N5128/Phase2/OP-cache/Phase2_HSTprop_12964-v02.xmlThe scheduling data was generated by CASM 20.2.CASM was run in Phase II mode.(Tic-Visit
:proposal-id 12964
:visit-id "02"
:proposal-version -1
:trans-version "20120604"
:date "24-Jun-2012 15:41:55.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 2
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 3437840
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 12964
:visit-id "02"
:obset-id "02"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12964
:visit-id "02"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2677
:al-overhead-at-end 115
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 12964
:visit-id "02"
:orbit-number 2
:pcs-time 222
:si-vis-utilization 2788
:al-overhead-at-end 115
:internal-dur-at-end 1015
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)true20/private/var/folders/jt/65t705ws22v8k75jg8kvlmb000033p/T/OPVisit2594127496691791306.xmlThe scheduling data was generated by CASM 20.2.CASM was run in Phase II mode.(Tic-Visit
:proposal-id 12964
:visit-id "03"
:proposal-version -1
:trans-version "20120604"
:date "29-Jun-2012 00:37:50.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 2
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 3437840
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 12964
:visit-id "03"
:obset-id "03"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12964
:visit-id "03"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2677
:al-overhead-at-end 115
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 12964
:visit-id "03"
:orbit-number 2
:pcs-time 222
:si-vis-utilization 2788
:al-overhead-at-end 115
:internal-dur-at-end 1015
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)true20/Users/mrejkuba/Work/proposals/HST_C20/N5128/Phase2/OP-cache/Phase2_HSTprop_12964-v04.xmlThe scheduling data was generated by CASM 20.2.CASM was run in Phase II mode.(Tic-Visit
:proposal-id 12964
:visit-id "04"
:proposal-version -1
:trans-version "20120604"
:date "24-Jun-2012 15:42:14.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 2
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 3437840
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 12964
:visit-id "04"
:obset-id "04"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12964
:visit-id "04"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2677
:al-overhead-at-end 115
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 12964
:visit-id "04"
:orbit-number 2
:pcs-time 222
:si-vis-utilization 2788
:al-overhead-at-end 115
:internal-dur-at-end 1015
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)true20/Users/mrejkuba/Work/proposals/HST_C20/N5128/Phase2/OP-cache/Phase2_HSTprop_12964-v05.xmlThe scheduling data was generated by CASM 20.2.CASM was run in Phase II mode.(Tic-Visit
:proposal-id 12964
:visit-id "05"
:proposal-version -1
:trans-version "20120604"
:date "24-Jun-2012 15:42:19.0"
:trans-errors '(:WARNINGS 0 :ERRORS 0 :HEALTH-AND-SAFETY 0
:FATAL-ERRORS 0 :CONTINUABLE-FATALS 0)
:number-of-orbits 2
:saa-model "29"
:si-bright-earth-limb-angle 20.0
:data-volume 3437840
:tdrss-contact-duration 0
:coron NIL
)
(Tic-Obset
:proposal-id 12964
:visit-id "05"
:obset-id "05"
:pcs-mode "FGS"
)
(Tic-Orbit
:proposal-id 12964
:visit-id "05"
:orbit-number 1
:pcs-time 333
:si-vis-utilization 2677
:al-overhead-at-end 115
:internal-dur-at-end 0
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)
(Tic-Orbit
:proposal-id 12964
:visit-id "05"
:orbit-number 2
:pcs-time 222
:si-vis-utilization 2788
:al-overhead-at-end 115
:internal-dur-at-end 1015
:dark-offset NIL
:dark-utilization 0
:max-dark-utilization 1920
:low-sky "N"
:pcs-visibility 3010
:pcs-gap 0
)true20