Daily Report #4515

HUBBLE SPACE TELESCOPE - Continuing to collect World Class Science

DAILY REPORT***** # 4515

PERIOD COVERED: UT December 27, 2007 (DOY 361)

OBSERVATIONS SCHEDULED

NIC1/NIC2/NIC3 11330

NICMOS Cycle 16 Extended Dark

This takes a series of Darks in parallel to other instruments.

NIC1/NIC2/NIC3 8795

NICMOS Post-SAA calibration - CR Persistence Part 6

A new procedure proposed to alleviate the CR-persistence problem of
NICMOS. Dark frames will be obtained immediately upon exiting the SAA
contour 23, and every time a NICMOS exposure is scheduled within 50
minutes of coming out of the SAA. The darks will be obtained in
parallel in all three NICMOS Cameras. The POST-SAA darks will be non-
standard reference files available to users with a USEAFTER date/time
mark. The keyword 'USEAFTER=date/time' will also be added to the
header of each POST-SAA DARK frame. The keyword must be populated with
the time, in addition to the date, because HST crosses the SAA ~8
times per day so each POST-SAA DARK will need to have the appropriate
time specified, for users to identify the ones they need. Both the raw
and processed images will be archived as POST-SAA DARKSs. Generally we
expect that all NICMOS science/calibration observations started within
50 minutes of leaving an SAA will need such maps to remove the CR
persistence from the science i mages. Each observation will need its
own CRMAP, as different SAA passages leave different imprints on the
NICMOS detectors.

NIC3 11064

CYCLE 15 NICMOS SPECTROPHOTOMETRY CALIBRATION PROGRAM

Now that the spectrophotometric capabilities of the NICMOS grism have
been established, cycle 15 observations are needed to refine the
sensitivity estimates, to check for sensitivity loss with time, to
improve the accuracy of the linearity correction, to improve the
secondary flux standards by re-observation, and to expand the G206
data set now that the sky subtraction technique has been shown to
produce useful fluxes for some of the fainter secondary standards.
These faint secondary IR standards will be a significant step towards
establishing flux standards for JWST, as well as for SNAP, Spitzer,
and SOFIA. 1.Re- observe the 3 primary WDs GD71, G191B2b, & GD153
twice each, once at the beginning and once near the end of the 18
month cycle. To date, we have only 2 observation of each star, while
the corresponding STIS data set for these primary standards ranges
from 6 to 23 obs. No observations exist for GD71 or GD153 with G206,
so that the current G206 sensitivity is defined solely by G191B2B.
Purposes: Refine sensitivities, measure sens losses. Orbits: 2 for
each of 6 visits = 12 2. Re-observe WD1057 & WD1657 plus another P041C
lamp-on visit to improve the scatter in the non-lin measurements per
Fig. 8 of NIC ISR 2006-02. The WD stars require 2 orbits each, while
the lamp-on test is done in one. The very faintest and most crucial
standard WD1657 has 2 good visits already, so to substantially improve
the S/N, two visits of two orbits are needed. Include G206 for P041C
in the lamp-off baseline part of that orbit. Orbits: WD1057-2,
WD1657-4, P041C-1 -- 7 3. Re-observe 9 secondary standards to improve
S/N of the faint ones and to include G206 for all 9. BD+17 {3 obs} is
not repeated in this cycle. Four are bright enough to do in one orbit:
VB8, 2M0036+18, P330E, and P177D. Orbits:2*5+4=14 Grand Total orbits
over 18 month cycle 15 is 12+6+14=32 {Roelof will submit the P041C
lamp-on visit in a separate program.}

WFPC2 11124

The Origin of QSO Absorption Lines from QSOs

We propose using WFPC2 to image the fields of 10 redshift z ~ 0.7
foreground {FG} QSOs which lie within ~29-151 kpc of the sightlines to
high-z background {BG} QSOs. A surprisingly high fraction of the BG
QSO spectra show strong MgII {2796,2803} absorption lines at precisely
the same redshifts as the FG QSOs. The high resolution capabilities of
WFPC2 are needed to understand the origin of these absorption systems,
in two ways. First, we wish to explore the FG QSO environment as close
as possible to the position of the BG QSO, to search for interloping
group or cluster galaxies which might be responsible for the
absorption, or irregularly shaped post-merger debris between the FG
and BG QSO which may indicate the presence of large amount of
disrupted gas along a sightline. Similarly, high resolution images are
needed to search for signs of tidal interactions between any galaxies
which might be found close to the FG QSO. Such features might provide
evidence of young merging events causing the start of QSO duty cycles
and producing outflows from the central AGN. Such winds may be
responsible for the observed absorption lines. Second, we seek to
measure the intrinsic parameters of the FG QSO host galaxy, such as
luminosity and morphology, to correlate with the properties of the
MgII absorption lines. We wish to observe each field through the F814W
filter, close to the rest-frame B-band of the FG QSO. These blue data
can reveal enhanced star formation regions close to the nucleus of the
host galaxy, which may be indicative of galaxy mergers with the FG QSO
host. The FG QSO environment offers quite a different set of phenomena
which might be responsible for MgII absorption, providing an important
comparison to studies of MgII absorption from regular field galaxies.

WFPC2 11202

The Structure of Early-type Galaxies: 0.1-100 Effective Radii

The structure, formation and evolution of early-type galaxies is still
largely an open problem in cosmology: how does the Universe evolve
from large linear scales dominated by dark matter to the highly
non-linear scales of galaxies, where baryons and dark matter both play
important, interacting, roles? To understand the complex physical
processes involved in their formation scenario, and why they have the
tight scaling relations that we observe today {e.g. the Fundamental
Plane}, it is critically important not only to understand their
stellar structure, but also their dark-matter distribution from the
smallest to the largest scales. Over the last three years the SLACS
collaboration has developed a toolbox to tackle these issues in a
unique and encompassing way by combining new non-parametric strong
lensing techniques, stellar dynamics, and most recently weak
gravitational lensing, with high-quality Hubble Space Telescope
imaging and VLT/Keck spectroscopic data of early-type lens systems.
This allows us to break degeneracies that are inherent to each of
these techniques separately and probe the mass structure of early-type
galaxies from 0.1 to 100 effective radii. The large dynamic range to
which lensing is sensitive allows us both to probe the clumpy
substructure of these galaxies, as well as their low-density outer
haloes. These methods have convincingly been demonstrated, by our
team, using smaller pilot-samples of SLACS lens systems with HST data.
In this proposal, we request observing time with WFPC2 and NICMOS to
observe 53 strong lens systems from SLACS, to obtain complete
multi-color imaging for each system. This would bring the total number
of SLACS lens systems to 87 with completed HST imaging and effectively
doubles the known number of galaxy-scale strong lenses. The deep HST
images enable us to fully exploit our new techniques, beat down
low-number statistics, and probe the structure and evolution of
early-type galaxies, not only with a uniform data-set an order of
magnitude larger than what is available now, but also with a fully
coherent and self-consistent methodological approach!

FLIGHT OPERATIONS SUMMARY:

Significant Spacecraft Anomalies: (The following are preliminary
reports of potential non-nominal performance that will be
investigated.)

HSTARS:

11123 - REAcq2,3,2) failed to RGA Hold (Gyro Control)

REAcq(2,3,2) scheduled at 361/16:02:00 - 16:10:05 failed to RGA Hold
due to a Search Radius Limit Exceeded Error on FGS-2. ESB 1805
(T2G_MOVING)TARGET_DETECTED) was received at 361/16:02:39 post-OBAD2.
One ESB "a05" (FGS Coarse Track failed-Search Radius Limit Exceeded)
was received at 361/16:07:34. Pre-acquisition OBAD1 attitude
correction value not available due to LOS. Pre-acq OBAD2 had (RSS)
value of 44.61 arcseconds. Post-acq OBAD/MAP had (RSS) value of 194.34
arcseconds. At 361/16:14:07 Equation F3SOB flagged indicating
Stuck-on-Bottom. (OPS REQUEST 17597-9) FHST Stuck-on-Bottom Macro was
executed at 361/16:18:49. F3SOB was back in bounds at 361/16:19:12.

Subsequent REAcq(2,3,2)scheduled at 361/17:38:42 was successful.

COMPLETED OPS REQUEST:

17597-9 - FHST Stuck-on-Bottom Macro Execution

COMPLETED OPS NOTES: (None)

*********************** SCHEDULED***** SUCCESSFUL

FGS GSacq************** 07***************** 07
FGS REacq************** 08***************** 07
OBAD with Maneuver **** 30***************** 30

SIGNIFICANT EVENTS: (None)