Hubble Space Telescope
Cycle 11 General Observer Proposal
General Observer proposal
Distant objects observation by HST with two
gravitational lensing galaxies abell1689 and
J1000+0221
Principal Investigator: Mr. Lienong XU
Institution: Wassamatta U.
USA/NY
Electronic mail: boris@wassamattau.edu
Scientific category:
Scientific keywords:
COSMOLOGY
GRAVITATIONAL LENSING, DISTANT GALAXIES,
ABELL 1689, J1000+0221
Instruments: ACS, NICMOS, STIS Proprietary period: 0
Cycle 11 primary orbits: 40
Cycle 11 parallel orbits: 0
Special Proposal Types: Innovative
Abstract
This proposal is designed to acquire the HST to carefully observe those good gravitational lensing galaxies(Abell 1689, CLJ1226+3332) and the potential extremely distant
astronomical objects which are exactly amplified by these galaxies. There is always great
curiosity about how and what to observe the early universe. In recent years scientists found
the gravitational lensing(GL) will be a promising approach. The GL is a direct consequence
of Einsteins general relativity. The lensing will be significant on a cosmological scale and it
can be treated as a powerful device rather than a pure cosmological effect. The intervening
galaxies between observers and distant objects will act as a microscope for observers by its
huge amount of mass. This technique offers a chance that those distant objects could be
resolved and measured with basic quantities. Scientists have already made great effort to
examine the proper lensing galaxies. The success of a team who previously used HST to
take images of distant quasar with accretion disks also strongly encouraged the opportunity
to better observe those far away luminous objects. The data collected of the distant objects
will both provide deep insight of the earlier universe and reduce the uncertainties of current
cosmological parameters.
Mr. Lienong XU
Distant objects observation by HST with two gravitational lensing galaxies abell1689 and
J1000+0221
Investigator
Mr. Lienong XU
Dr. Stan Theman
Institution
Wassamatta U.
U. Two
PI:
CoI:
CoI:
Total number of investigators:
3
Observing Summary:
Target
RA
ABELL 1689 13h 11m 34.2s
J1000+0221
150.077
DEC
01 21 56
+2.361
Configuration,mode,aperture
spectral elements
IMAGING F270W
Visible/NIR IMAGING
(F606W, F814W, F125W,
F160W
Grand total orbit request
V
16
2
Country
USA/NY
Kurdistan
Total
orbits
20
20
40
Flags
CPAR
CPAR
Mr. Lienong XU
Distant objects observation by HST with two gravitational lensing galaxies abell1689 and
J1000+0221
Scientific Justification
It is always true that the further we see the earlier the universe we find and the better the
level of our understanding of our universe as a whole both spatially and temporally. That
is the ultimate reason why astronomers never stop to invent and improve those powerful
telescopes in order to get clear images of distant objects. The better resolution we have, the
more ambitious we are to observe farther objects. The primitive eagerness to look deeper
contributes the great importance of this proposal. Due to Hubble flow, distant objects are
highly red shifted (high z). By observing the galaxies with those high z values would help
a lot for determine more accurate value of Hubble constant and acceleration rate of the
universe.
Gravitational lensing (strong) is a well-proposed method to satisfy the desire to look
further in universe. The physics behind is simply that mass will bent the light governed
by general relativity. Therefore the light from a distant object we see are deflected by the
intermediate massive galaxies as lenses. The strong GL effect would cause multiple images of
a single object or Einstein Rings due to light follows different paths. Careful mathematical
calculation based on the lensing data can be conducted to derive the true information of the
distant objects. This technique avoids the limitation of the telescope power itself. Instead
scientists turned to find good candidates of lensing object in universe hence it is equivalently
boosting the power of the original telescope. The scientists team CLASH(Cluster Lensing
And Supernova survey with Hubble) and CLASS(Cosmic Lens All Sky Survey) has carefully
searched and examined several massive galaxies and clusters which turned out to be qualified
lenses. This achievement thus opened the window to probe those distant objects.
Apart from more accurate measurement of those cosmological parameters, the clear
images of the universe in early ages taken with the assist of gravitational lensing would
probably provide certain objects whose physical structures including shape, size and chemical
compositions are not well determined. Accretion disk(AD) from a typical distant quasar is
a great illustration of realization of gravitational lensing. AD activates the radioactive polar
jet from the rotational axis. It is believed that the polar jet events such as quasars are one
of the brightest objects in the universe and the most energetic astronomical events. Thus
a full study of this high energy but fundamental structure could tell us how physics works
exactly at such large energy scale. Black hole also is involved in quasars and surrounded by
AD. Definitely there is abundant information about black holes within the properties of AD
.
Despite the importance of accretion disks, the detailed structure of different types of
accretion disks is poorly understood in terms of observation. What the astronomers achieved
is several convincing models for the accretion disks base theories in physics. For those
quasars, they are just much too far away to be resolved though their sizes are already
incredibly large by model prediction. Once we are able to observe the resolved images of
these objects, we can thoroughly test the fitness of current models and later modify the
models of accretion disks and polar jets more realistic and precise. So far there is a team
of scientists who successfully obtain several good quality images of far away accretion disc
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Mr. Lienong XU
Distant objects observation by HST with two gravitational lensing galaxies abell1689 and
J1000+0221
exactly by the simple but powerful gravitational lensing technique. They really performed
detailed measurement of accretion disks. These researchers roughly estimated the size of the
particular quasar and details in deeper level like color change and temperature distribution
across the quasars size. All the measurements showed a huge improvement compared with
the traditional observation without GL.
Above all GL observations do enlighten the prospective future development. The benefit
it produces deserves to use HST observation. Meanwhile it is also necessary to use the HST.
The observing objects are really distant hence the measurement will be deviate dramatically
if the observation itself contains too big uncertainties. Those negative factors caused by
atmosphere should be avoided (using HST) in order to achieve idealized situation. On the
other hand, the phenomena of gravitational lensing, even the strong gravitational lensing
happens in a tiny region in the sky. Hence precise focusing is required and HST is so
well-functioned to observe a small specific region for details.
Description of the Observations
The proposed observation is designed to observe two galaxies, Abell 1689 and J1000+0221
which are confirmed to be good gravitational lens. The A1689-zD1 magnified by Abell
1689 is one of the most distant galaxies, the tremendously high red shift of this galaxies
produce valuable data measurement for cosmological parameter and the early universe. The
J1000+0221 is founded to be one of the most distant GL galaxies with a redshift about 1.53.
High red shift lenses are rare. This increase the importance of detailed study of J1000+0221.
The galaxies itself definitely contains enough useful information rather than the source object
it lenses. These two galaxies are qualified representatives of GL and deserves to be observed
with great details by the previous discussion in the scientific justification.
Each of the galaxies is scheduled to utilize 20 orbits of the HST. The two targets can
be directly pointed by RA and Dec coordinates. The calibration can be settled by checking
whether it images show the GL effect such as multiple close indentical objects or Einstein
ring. Images are supposed to be taken with V band, IR and NIR bands based on previous
observation of these targets by HST. Near Infrared Camera and Multi-Object Spectrometer
are necessary to catch the extremely faint source objects even though they are magnified
by GL. The exposure times are chosen to be 100, 120 and 140 seconds. The relatively long
exposure times are required because the objects are indeed very far away. It is better to
collect more photons to make the images analyzable Though it would increase signal to noise
ratio.
After the Hubble observation, it is expected to gain enough high quality pictures of both
the lensing galaxies and the distant source objects. By spectroscopy method, their respective
redshift could be calculated. Uncertainties could be reduced compared with previous results
due to more available and reliable images. Careful study of the Einstein ring could reveal
the amplification of the source objects and further estimate the mass of the lensing galaxies.
There is a branch of discussion here. The mass due to the lensing effect shall be bigger than
the mass estimated by luminosity derivation, the discrepancies produced by the dark matters
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Mr. Lienong XU
Distant objects observation by HST with two gravitational lensing galaxies abell1689 and
J1000+0221
which contribute huge mass. A reasonable fraction of dark matter to visible baryonic matter
could be extracted from these data. All of these lensing galaxies measurements would be
elaborated and future observation of potential new source objects benefits from the precise
information of the lensing galaxies.
The distant sources objects, as mentioned before, are highly redshifted. A1689-zD1, the
source object of Abell 1689, has a red shift 7.6 and distance 12.8 biliion light years. After
the reobservation, the two numerical data precision could be enhance and produce better
constraint on Hubble constant and acceleration parameter of universe expansion which is
crucial for researchs about dark energy. The lensing images will show how the galaxies look
like in the early universe and the spectral data could illustrate the chemical compositions
of the galaxies. Scientists then would testify or improve current theory of the evolution of
the galaxies. There is also target of opportunity of this GL observation, there may be other
astronomical objects like quasars or supernovas lies exactly behind the lensing galaxies.
In conclusion, so far the GL is the best way to observe the really distant objects we
want. Also the development of this technique is already sophisticated. This offers great
convenience for data analysis. The expected measurements of the source targets will be
fruitful ensured by their great distances.
Special Requirements
I may require a lot of help, but I need no specific special scheduling requirements.
Coordinated Observations
No, I’m pretty much uncoordinated.
Justify Duplications
Abell 1689 was observed by HST in 2008 J1000+0221 was observed by HST in 2013
Previous HST Programs
None (and for good reason, too).
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