More rambles on cosmic string lenses
Schild et al (A&A 422 477) discuss a string lens candidate, namely the classic lensed quasar Q0957+561.
This quasar has a well studied time delay, used to get an independent estimate of Hubble's constant, H0. or equivalently, the expansion rate of the universe. Analysis shows a second time scale for the time delay between the two images, which has been suggested is due to microlensing in the lensing galaxy. The new claim is for a third time scale, at low amplitude variability, with zero time delay offset - consistent with string lensing.
Sorry, but I don't believe it. The model parameters are implausible (if I read it correctly they require the lensing string be in the Milky Way, only 10,000 light years away), and the alignment with a classic lens is a priori very unlikely. Likely there's some instrumental systematic here, problem with baseline photometry.
Back to CSL-1: quick glance at the spectrum does not show any obvious AGN emission lines, so maybe x-ray observation is not a good bet - though if there were identical luminosity x-ray emitting nuclei in both images, it would strengthen the case, and there could be room for a low luminosity AGN, but one still detectable with Chandra. Similarly radio observation looking for low frequency radio emission would be a test, if both images had identical emission.
astro-ph/0406516, but Sazhin et al, discusses the statistics of close pairs of faint extended sources in the field, and the possibility of multiple other lenses along the string trajectory - they claim 11 source pairs (7-9 expected for a straight string, more for a curved string, so implication is a lightly curved string). Too early to tell if these are real, of course, but if they are, they've not only found a string but mapped it...
Still a long shot, but not crazy. Certainly worth some followup.
By someone.
This quasar has a well studied time delay, used to get an independent estimate of Hubble's constant, H0. or equivalently, the expansion rate of the universe. Analysis shows a second time scale for the time delay between the two images, which has been suggested is due to microlensing in the lensing galaxy. The new claim is for a third time scale, at low amplitude variability, with zero time delay offset - consistent with string lensing.
Sorry, but I don't believe it. The model parameters are implausible (if I read it correctly they require the lensing string be in the Milky Way, only 10,000 light years away), and the alignment with a classic lens is a priori very unlikely. Likely there's some instrumental systematic here, problem with baseline photometry.
Back to CSL-1: quick glance at the spectrum does not show any obvious AGN emission lines, so maybe x-ray observation is not a good bet - though if there were identical luminosity x-ray emitting nuclei in both images, it would strengthen the case, and there could be room for a low luminosity AGN, but one still detectable with Chandra. Similarly radio observation looking for low frequency radio emission would be a test, if both images had identical emission.
astro-ph/0406516, but Sazhin et al, discusses the statistics of close pairs of faint extended sources in the field, and the possibility of multiple other lenses along the string trajectory - they claim 11 source pairs (7-9 expected for a straight string, more for a curved string, so implication is a lightly curved string). Too early to tell if these are real, of course, but if they are, they've not only found a string but mapped it...
Still a long shot, but not crazy. Certainly worth some followup.
By someone.
posted by Steinn at 4:35 PM
1 Comments:
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http://groups.yahoo.com/group/AstroDeep/17
CSL-1 cosmic string Hubble view due 2006 February,
T Vachaspati, D Huterer, C Hogan: James Renner, freetimes.com:
primordial H filaments easily visible in HUDF background, Murray 2005.12.27
http://www.freetimes.com/modules.php?op=modload&name=
News&file=article&sid=2809
Free Times: Ohio's premium news, arts and entertainment weekly
Tuesday, December 27, 2005 01:41 AM
Master of the Universe:
A local professor’s legacy hinges on a galaxy far, far away
By James Renner jrenner@freetimes.com 216-479-2033 X 253
Vachaspati : [ photo ]
The cosmic string “could be one of the greatest discoveries in history.”
NORMALLY, debating the nature of the universe happened in the afternoon.
That’s when Tanmay Vachaspati stepped into the office next to his —
the one occupied by postdoctoral student Dragan Huterer —
armed with a bag of almonds and an open mind.
Other times these discussions happened over Friday dinners
at some East Side restaurant with the other
Case Western Reserve University physicists.
Occasionally, they would rant about things like “dark energy”
over drinks at the bar.
But one morning in August 2003, routine was discarded.
Vachaspati was too excited to wait for lunch.
The physics department at Case was buzzing with conversation.
He met up with Huterer over a cup of coffee to talk about the news.
A team of European scientists had just announced a tantalizing discovery.
A photograph appeared to show two identical galaxies sitting side by side
in the heavens. Upon closer inspection, though, it seemed they were actually
one galaxy, its image split in two by some massive invisible object
floating in the void between Cleveland and the edge of the universe.
It could be only one thing: a fabled “cosmic string.”
“What can we do to verify this?” asked Vachaspati.
Huterer understood his mentor’s excitement and desire for quick confirmation.
Cosmic strings are remnants of the early universe,
strange gossamers formed just after the Big Bang.
If the universe is a giant lake,
think of these cosmic strings as the cracks that form in the ice
when it freezes over.
They are millions of miles long and thinner than a spaghetti noodle.
Each centimeter of a cosmic string weighs as much as Mount Everest;
they are so heavy they bend light traveling near them.
Cosmic strings gave structure to the early universe,
binding it together, forming galaxies in their gravitational wake.
Vachaspati had been searching for one for nearly 20 years.
Albert Einstein died still searching for a single theory to explain
how the universe works. If the experiment Huterer and Vachaspati
devised in their offices at Case goes as planned,
Einstein may finally be able to rest in peace.
It’s four miles from Vachaspati’s house in Shaker Heights
to his office on the campus of Case Western Reserve University,
but the physics professor likes to walk.
Along the way, he listens to tracks of classical Indian vocals
he downloads from the Internet.
“This is a great invention,” says Vachaspati, showing off his iPod.
“Just beautiful.”
During these walks he finds inspiration, new theories
to explain the mysteries of the universe.
“It’s undisturbed time. I can just think. That’s when the best ideas come.”
His office at Case is spartan.
Vachaspati sits behind a large wooden desk, leaning forward
so his dark bangs hang out over eyes wide-open with excitement.
He looks 25, but is really 46.
On the wall is a letter from his 4-year-old daughter.
It reads: “Dear papa you are a hard working man.
You wright long things. I wish I could read Pheseces.”
It’s her attempt to spell physics, a word she already associates with dad.
Hanging by the door is a framed photograph of Vachaspati’s father
standing next to Niels Bohr, the father of quantum mechanics,
a celebrity in the world of theoretical physics. It was Vachaspati’s father —
and a magazine subscription — that propelled him to America in 1980.
In Allahabad, India, it was expensive to subscribe to magazines
from the United States. But Vachaspati’s father, also a physicist,
wanted a subscription to a particular science magazine that came free
to new members of the American Physical Society.
So Vachaspati joined APS as a student member to get the magazine
for his father. At the time, information on student members of APS
was given to universities. Soon, Vachaspati was sifting through
brochures from American colleges. He filled out and returned
the applications on a whim. Stony Brook in Long Island and
Tufts in Boston responded with scholarships.
“The only American in town was a psychology professor,”
says Vachaspati. “I asked him which college I should go to.
He said, ‘Oh, I like Boston better.’”
When it came time to write his Ph.D. at Tufts,
he devised theories to detect cosmic strings.
These ideas formed the basis of the European discovery.
The team cited Vachaspati in a paper
they published in a Russian science journal.
Vachaspati’s work in Cleveland is not limited to hunting cosmic strings,
though. During a recent commute, the physicist thought up a way
to detect Hawking radiation — energy that is ejected from black holes —
in the lab. It involved the creation of something called a “dumbhole,”
an object that gobbles up sound instead of light.
A five-minute-long conversation with this man will blow your mind.
And he has the patience to explain his theories
to the average armchair nerd. He wants people to understand his work
because he’s so excited about the possibilities —
especially this potential piece of cosmic string floating in the void of space.
“I think it could be one of the greatest discoveries in history,” he says.
There is no doubt that CSL-1, the name given to the image
of these two identical galaxies, is something odd.
Skeptics say that’s all it is, just a pair of galaxies
with remarkable similarities that happen to be nearby each other.
Vachaspati and Huterer hope to silence the opposition
with a new theory they devised in their offices at Case.
“If it’s a string, it must be running through this whole region,”
says Vachaspati, pointing to a star chart.
“If you look closely, you should be able to see more pairs,” says Huterer.
Simple by concept, but this pair of scientists wanted to make it testable.
So they crunched numbers. Huterer understood the capabilities
of telescopes like the Hubble Space Telescope
from his experience searching the skies for signs of dark energy.
Vachaspati understood the nature of cosmic strings.
Working together, a testable theory presented itself.
According to their equations, if a telescope was pointed
in the direction of CSL-1,
five out of 100 objects nearby should also be split,
appearing as identical twins or fractured images.
In February, their theory will put to the test by an independent team
led by Craig Hogan, a physicist at the University of Washington.
His team has reserved time on Hubble.
The satellite will take detailed photographs of CSL-1
during the course of three orbits, using two different light filters.
“Conceivably, if it really is a string, we could see something spectacular,”
says Hogan. “We’re looking for more objects that are doubled
or have sharp edges. That would be the smoking gun.
It’s an important bit of fundamental physics that might be staring us in the face.”
And if the images prove Vachaspati’s theories?
“All the telescopes in the world will be pointing at the thing,” says Hogan.
Huterer is more to the point.
“It will certainly win a Nobel prize,” he says from his office
at the University of Chicago. Ultimately, the laurels will go
to the European team that discovered CSL-1,
but his mentor’s work in Cleveland set them in motion.
“I’m just waiting for the results,” says Vachaspati.
“I theorized about these things 20 years ago. Now, they’re getting hot.”
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http://www.cwru.edu/
http://www.phys.cwru.edu/faculty/index.php?vachaspati
Tanmay Vachaspati Professor of Physics
Ph.D., Tufts University (1985)
txv7@cwru.edu ; Phone: 216-368-0222
Cosmology, Particle Physics and Astrophysics
Interests Publications
RESEARCH INTERESTS:
Using cosmological observations to search for topological defects
and primordial magnetic fields,
including Cosmic Microwave Background Radiation
temperature anisotropy and polarization, gravitational lensing,
and gravitational waves.
Cosmology of topological defects.
Topological defects in particle physics
especially the standard electroweak model and their role in baryogenesis.
Classification of topological defects. Defect interactions.
Generation of primordial magnetic fields.
The topology of such magnetic fields.
Inflation, eternal inflation and quantum cosmology.
Cosmology in the laboratory and the design of experiments
to test ideas in quantum field theory in curved spacetime
such as Hawking radiation.
A dual model of the known fundamental particles.
http://kicp.uchicago.edu/~dhuterer/
Dragan Huterer
Astronomy and Astrophysics Department
University of Chicago 5640 S. Ellis Ave. Chicago, IL 60637
dhuterer[at]kicp.uchicago.edu ; Office phone: (773) 834-0392
I am an NSF postdoctoral fellow at Kavli Institute for Cosmological Physics
and the the Department of Astronomy and Astrophysics
at the University of Chicago. My field of research is theoretical cosmology.
Before this, I was a postdoc in the Particle-Astrophysics Group
at Case Western Reserve University,
before that a graduate student at the University of Chicago,
before that an undergraduate at MIT,
and still before that a student at Gimnazija "Ognjen Prica"
in Sarajevo, Bosnia and Herzegovina (then Yugoslavia).
I work on trying to understand the nature and properties of "dark energy",
a mysterious component that makes up about 70%
of the energy in the universe and makes it accelerate.
This includes using type Ia supernova measurements,
large-scale structure surveys and weak and strong gravitational lensing
as tools of precision cosmology.
I am also interested in testing the gaussianity and isotropy
of the cosmic microwave background radiation.
And I am a member of the SNAP collaboration,
a team that proposes to study dark energy using an ultimate probe --
a new space telescope, custom-built for this purpose.
http://www.phys.cwru.edu/projects/mpvectors/#contact
Craig J. Copi mpvectors@www.phys.cwru.edu
http://www.phys.cwru.edu/projects/mpvectors/#paper3
Paper 3 August 2, 2005
A paper collecting much of the work involving
multipole vectors performed by us and by others.
It provides a review of the multipole vector formalism and extensions to it.
We focus mainly on the lowest cosmological multipoles (l=2 and 3)
and show that alignment between the planes they define
and the ecliptic persists at > 99.9% C.L.
We explore many other alignments and extend the analysis
in ways to address some systematics.
This paper can be found on astro-ph and has been submitted
to Monthly Notices of the Royal Astronomical Society.
You can download the paper with high resolution (and thus large)
figures as either hi-res postscript (compressed, approximately 980kB)
or hi-res pdf (approximately 850kB).
http://www.arxiv.org/abs/astro-ph/0508047/
Astrophysics, abstract
astro-ph/0508047
From: Craig Copi cjc5@cwru.edu ;
Date: Mon, 1 Aug 2005 20:07:39 GMT (282kb)
On the large-angle anomalies of the microwave sky
Authors:
C. J. Copi (1), cjc5@cwru.edu ;
D. Huterer (2), dhuterer[at]kicp.uchicago.edu ;
D. J. Schwarz (3), dominik.schwarz@cern.ch ;
G. D. Starkman (1) glenn.starkman@case.edu ;
Dominik J. Schwarz, Glenn D. Starkman, Dragan Huterer, and Craig J. Copi
(1) Case Western Reserve University,
(2) University of Chicago,
(3) Universitat Bielefeld)
Comments: 26 pages, 7 figures. High resolution figures,
multipole vector code and other information can be found at this http URL
[Abridged] We apply the multipole vector framework to full-sky maps
derived from the first year WMAP data.
We significantly extend our earlier work
showing that the two lowest cosmologically interesting multipoles, l=2 and 3,
are not statistically isotropic.
These results are compared to the findings obtained using related methods.
In particular, the planes of the quadrupole and the octopole
are unexpectedly aligned.
Moreover, the combined quadrupole plus octopole is surprisingly
aligned with the geometry and direction of motion of the solar system:
the plane they define is perpendicular to the ecliptic plane
and to the plane defined by the dipole direction,
and the ecliptic plane carefully separates stronger from weaker extrema,
running within a couple of degrees of the null-contour
between a maximum and a minimum over more than 120 deg of the sky.
Even given the alignment of the quadrupole and octopole with each other,
we find that their alignment with the ecliptic is unlikely at >98% C.L.,
and argue that it is in fact unlikely at >99.9% C.L.
We explore the role of foregrounds showing that the known
Galactic foregrounds are unlikely to lead to these correlations.
Multipole vectors, like individual a_lm, are very sensitive to sky cuts,
and we demonstrate that analyses using cut skies induce relatively large errors,
thus weakening the observed correlations
but preserving their consistency with the full-sky results.
Finally we apply our tests to COBE cut-sky maps
and briefly extend the analysis to higher multipoles.
If the correlations we observe are indeed a signal of non-cosmic origin,
then the lack of low-l power will very likely be exacerbated,
with important consequences for our understanding of cosmology on large scales.
Full-text: PostScript, PDF, or Other formats
Anne M. Green
Stefan Hofmann shofmann@perimeterinstitute.ca ;
Lidia Pieri lidia@physto.se ;
http://www.astro.washington.edu/hogan/
Dr. Craig J. Hogan Professor of Astronomy Professor of Physics
University of Washington PO Box 351202 Seattle, WA 98195
206-685-2112 voice 206-685-0403 fax hogan@u.washington.edu ;
Craig Hogan graduated from Harvard College and went on to
King's College, Cambridge, where he earned his Ph.D. in 1980.
He held postdoctoral prize fellowships at the University of Chicago
and Caltech, and was on the faculty at the University of Arizona's
Steward Observatory before moving to Seattle in 1990.
From 1995 to 2001 he served as Chair of Astronomy
and in 2001-2002 as Divisional Dean of Natural Sciences
in the College of Arts and Sciences.
From 2002 to 2005 he served as UW's Vice Provost for Research.
He has served on boards and advisory committees
for many agencies, laboratories, and research organizations.
Hogan's scholarship in cosmology has been recognized
by an Alfred P. Sloan Foundation Fellowship
and an Alexander von Humboldt Research Award.
As a member of the High-z Supernova Search Team
he was a co-discoverer of the cosmic "Dark Energy"
causing the expansion of the universe to accelerate.
Currently, he is a member of the International Science Team for LISA,
a space mission under development to detect gravitational radiation.
Hogan's current theoretical research centers
on the astrophysical phenomenology of string theory and quantum gravity,
for example in the cosmic background radiation anisotropy,
and the generation and detection of stochastic
gravitational wave backgrounds from events in the early universe
such as phase transitions and the formation of our 3-dimensional space.
Recent technical papers are posted at the astro-ph archive.
His primer on cosmology, "The Little Book of the Big Bang" ,
published by Springer-Verlag, has been translated into
Dutch, Portuguese, German, Italian, Polish, and Greek.
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http://groups.yahoo.com/group/AstroDeep/16
skeptical note re "RML-1" photo # 31, 3.75 arc-sec wide, from Hubble
Ultra Deep Field, on www.Flickr.com AstroDeep site: Motl:
Murray 2005.11.21
http://motls.blogspot.com/2005/11/cosmic-string-or-dark-matter.html
Lubos Motl's Reference Frame blog
http://schwinger.harvard.edu/~motl/sf/frames.html
Lubos Motl motl@feynman.harvard.edu
(pronounce: "Loo-bosch Maw-tull")
Friday, November 11, 2005
Cosmic string or dark matter
I just received a mail from Rich Murray who has taken many pictures of the
region near CSL-1, the "cosmic string lensing" candidate.
See his pictures at flickr.com
For example, the newest picture #31 at the top includes "RML-1" which
stands for "Rich Murray Lens 1", but I remain somewhat unconvinced
that this rather amateurish picture proves anything.
The primary recipient of the e-mail was Malcolm Fairbairn who just
posted an interesting paper arguing that if the CSL-1 event is caused
by lensing, it is likely to be a cosmic string rather than a dark
matter filament because in the latter case, the corresponding tidally
disrupted dark matter halo would have to be as heavy as the Milky Way
-- and such a halo seems to be absent in other data.
This was always our primary worry -- that CSL-1 could be caused by
lensing by something that just acts as a string but can be of a rather
conventional origin.
posted by Lumo at 11:18 PM
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November 21, 2005
Well, "...I remain somewhat unconvinced that this rather amateurish
picture proves anything." is the highest praise that this absolute
amateur has so far received since June.
I was surprised to see the number of visits to the 31 photos on
www.Flickr.com site, AstroDeep , jumping from just over 200 to now
866, so I am grateful to know who to credit -- Thanks!
Only the first 17 photos are from the CSL-1 field, the next two are
from the Millenium Simulation, then 20 to 31 are selected and imaged
processed from the Hubble Ultra Deep Field. More important than the
possibility that the double blue galaxy in #31 is lensed by a cosmic
string, are the myriad bright blue 1-2 pixel (0.03 arc-sec) sources,
which are always on a faint, but obvious upon scrutiny, fractile 3D
dark mesh, that is backlit by a uniform faint maroon glow.
Just 104 views so far of this one -- I welcome all feedback -- no need
to be positive or even polite, though humor is always appreciated....
Rich Murray rmforall@comcast.net
1943 Otowi Road, Santa Fe, New Mexico 87505 505-501-2298
http://groups.yahoo.com/group/AstroDeep/
http://groups.yahoo.com/group/AstroDeep/15
two classes of readily noticeable common, ubiquitous, uniform bright
blue sources in deep background (Murray mesh) of HUDF, dwarf galaxy
luminous bare clumps, hyper novae?: 2005.04.01 BG and DM Elmegreen:
Malcolm Fairbairn: Murray 2005.11.11
[ You can search the title on Google Groups to find this post. ]
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http://groups.yahoo.com/group/AstroDeep/15
two classes of readily noticeable common, ubiquitous, uniform bright
blue sources in deep background (Murray mesh) of HUDF, dwarf galaxy
luminous bare clumps, hyper novae?: 2005.04.01 BG and DM Elmegreen:
Malcolm Fairbairn: Murray 2005.11.11
November 11, 2005 Hello Malcolm,
I hope it best answers your questions to give a long,detailed answer
that shows you how to access the 31 images on my Flickr.com archive,
and quotes the complete notes I wrote for each image,
moving in three steps from deepest closeup to the HUDF.
The public HUDF uses blue to represent received blue light.
It happens that RML-1 and many very similar pairs, are bright blue,
which I have emphasized by shifting the colors to emphasize blue,
without losing significant data for the red.
As a layman, I am guessing that these are very bright UV sources,
redshifted to blue.
Are they large ellipticals like CSL-1, small early galaxies,
or smaller "bare", "clump luminous masses", "gas-rich dwarf galaxies",
"small field objects are more the size of the z ~6 galaxies
studied by Bunker et al. (2004)."?
"These galaxies are members of a class dominated
by 5 to 10 giant clumps, and having no exponential disk or bulge.
The redshifts are found to be in the range from 1.6 to 3.
The clump emission is typically 40% of the total galaxy emission and
the luminous clump mass is 19% of the total galaxy mass.
The clump colors suggest declining star formation
over the last ~0.3 Gy, while the interclump emission is redder than
the clumps, corresponding to a greater age.
The clump luminous masses are typically 6 × 10E8 M(Sun) and their
diameters average 1.8 kpc, making their average density ~0.2 M(Sun)
pc-3......
.....or they could be captured as gas-rich dwarf galaxies,
flaring up with star formation at first and then dispersing.
Support for this second possibility comes from the high abundance of nearly
identical clumps in the UDF field, smaller than 6 pixels, whose
distributions on color-magnitude and color-color plots are the same as the
galaxy clumps studied here." 2005.04.01 Elmegreen BG, Elmegreen DM
From their text:
"4.2.2. Bare clumps in the UDF
What is the evidence for clumps like these outside of clump-cluster
galaxies, where they presumably existed before the accretion?
The UDF contains many isolated objects that resemble our clumps in both
luminosity and color.
The right-hand side of Figure 11 shows color-magnitude and color-color plots
of all the UDF objects smaller than 6 pixels in FWHM, as given in the
tabulation on the UDF web site (1).
This size limit was chosen because it roughly corresponds to the size of a
clump in a clump-cluster galaxy.
The left side of the figure shows the magnitudes and colors for the measured
clumps in the clump-cluster galaxies of this paper.
The distributions are essentially the same in the regions of overlap.
The UDF clumps can be much bluer than our clumps, suggesting either that
star formation begins to slow down once a clump is ingested into a larger
galaxy,
or the clump-cluster sample in our survey has too few clumps to include the
rare active ones seen in the general UDF field.
There are also much fainter clumps in the UDF field than those measured in
our survey, but the clump-cluster galaxies have much fainter clumps too
which we did not study.
We note that these small objects in the UDF field are not the well-studied
Lyman Break galaxies,
which tend to be more massive, blue, and luminous than our clumps even at
the same z ~2.5 - 3 (e.g., Papovich, Dickinson, & Ferguson 2001).
The small field objects are more the size of the z ~6 galaxies studied by
Bunker et al. (2004).
Most likely, most are low-mass and low-luminosity galaxies in about the same
range of redshifts as the clump-cluster galaxies studied here.....
[ Bunker, A., Spinrad, H., Stern, D., Thompson, R., Moustakas, L., Davis,
M., & Dey, A. 2000, in Galaxies in the Young Universe II, ed. H. Hippelein &
K. Meisenheimer (Berlin: Springer) ]
These considerations suggest that the clumps in some of our clump-cluster
galaxies could have been accreted as whole objects from the field."
The distance is greater, if the sources are smaller.
Predictions are that there are many more cosmic strings at earlier epoches.
The CMB is hotter with distance, and is ~3,000 deg K at age 380,000 years.
The initial H filaments have to cool down in order to collapse by gravity,
but then the first stars are ultramassive, ultrahot, short-lived extreme UV
sources that become hypernovae, quasars, and black holes.
As a layman, I conjecture that they are the myriad uniform bright blue
sources, 1-2 pixels,
always on a background fractile 3D dark mesh,
backlighted by a faint reddish glow,
which then would be redshifted CMB
prior to the formation of the mesh of H filaments.
The HUDF pixels are 0.03 arc-sec.
In that case, repeated exposures every few months of large fields
should show the rate of appearance and disappearance
of these extreme sources,
which have a lifetime on the order of 1 to 10 million years.
These are exciting vistas to appreciate,
immediately openning up a major frontier in astrophysics.
In mutual service, Rich
Rich Murray, MA Room For All rmforall@... 505-501-2298
1943 Otowi Road Santa Fe, New Mexico 87505 USA
http://groups.yahoo.com/group/AstroDeep/
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http://groups.yahoo.com/group/AstroDeep/12
more candidate cosmic string lens pairs in HUDF (re comment by Levon
Pogosian on astro-ph/0506400); also myriad minute bright blue sources,
always on dark background mesh: Murray 2005.11.10
http://groups.yahoo.com/group/AstroDeep/11
subtle background structure in deep astronomy photos; CSL-1 cosmic string
gravitational lens in Capodimonte Deep Field; Millennium Simulation of
evolving cosmic structure; AstroDeep group; Murray mesh; www.Flickr.com
photo archive: Murray 2005.06.10
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http://www.flickr.com/photos/rmforall/
31 images with detailed comments and links
Click in the lower left area just below Your Photos on Your Photo Page
Then click on the top photo #31 (#21) astrodeep200407aecb
Here is the text for this image,
the most magnified closeup I give from HUDF,
a view 3.75 X 3.75 arc-sec, with RML-1 0.4 X 0.2 sec --
ten times less long than CSL-1 :
#31 (#21) Closeup of possible cosmic string gravitational lens,
the blue galaxy pair, very similar to CSL-1,
just above yellow galaxy in lower left corner of #20 and #22,
magenta in #23. I call it RML-1, Rich Murray Lens 1.
The 125 X 125 pixel field was cropped from #23,
and expanded to fit the page,
and saved as tif 2.25 MB and this png .087 MB image.
The pixels are .03 arc-second each, so that the original
Hubble Ultra Deep Field, 6200 X 6200 pixels, is 186 X 186 arc-seconds,
3.1 X 3.1 arc-minutes, a tenth of the diameter of the Full Moon or the Sun,
0.5 degrees, 30 arc-minutes.
This view is 125 X 125 p, 3.75 X 3.75 sec.
The length of the dumbell shape of the two blue galaxies is
1/9 of the 125 p width of the view, 14 X 7 p, 0.4 X 0.2 sec. --
ten times less long than CSL-1.
Notice the background scatter of bright blue sources, 1 to 2 pixel size,
and the dark background 3D mesh.
The bright blue sources, like tiny Christmas lights,
are always on the dark 3D mesh.
The coding at some stage in the image processing
has produced prevalent vertical straight line artifacts.
hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
Hubble reaches the final frontier: the dawn of galaxies
The Universe expanded from a tiny point 13.7 billion years ago.
By 380,000 years, time 0.000380 BY, the expanding hot atomic plasma,
made of electrons and protons, which had been opaque to light,
had cooled enough, 3,000 deg Kelvin,
to allow the free electrons to bind with the free protons
to form atoms of H, becoming a transparent gas --
by now these photons have cooled and redshifted
with the expanding space-time of the Universe
to become the ubiquitous 2.7 deg Kelvin cosmic microwave background, CMB.
But without stars, the universe was without light - the dark ages.
Gravity, very slowly at first, then faster and ever faster,
started pulling the initially slightly denser volumes of gas inward
to form complex fractile networks of increasingly dense filaments and nodes.
The first stars each formed within a single cloud
of about a million solar masses,
contracting to ignite a central mass of about 100 to 1000 solar masses.
These huge stars burned hotly and quickly for short lifespans
of a few million years,
and their intense ultraviolet light started to reionize the gas.
Many exploded as hypernovae, illuminating the Universe,
and venting huge amounts of heavier elements, called 'metals', into the
galactic gas.
Later stars, with increasing metal contents, were able to form more quickly
and were smaller, cooler, less bright, and much longer lived,
and so the masses of contracting gas
became clusters of hot, crooked dwarf galaxies.
This view may show this,
with the ultraviolet light from the early hyper novae
redshifted to the maroon color of the far background,
highlighting the complex 3D fractile dark network of condensing darker
filaments and nodes, which in turn give birth
to the hot, ultraviolet bright,
crooked dwarf galaxies, closer to us,
and so redshifted a lesser degree to bright blue.
arxiv.org/PS_cache/hep-th/pdf/0508/0508135.pdf
arXiv:hep-th/0508135 v2 25 Aug 2005
Cosmic strings: progress and problems. Alexander Vilenkin,
Institute of Cosmology, Department of Physics and Astronomy,
Tufts University, Medford, MA 02155, USA
' Another intriguing new development is the observation
of two nearly identical galaxies at redshift z = 0.46
with angular separation of 1.9 arc seconds [33].
The spectra of the two galaxies coincide at 99.9% confidence level [34].
The most plausible interpretation of the data appears to be
lensing by a cosmic string with Gµ ~ 4 × 10-7.
This estimate assumes a slowly moving string
orthogonal to the line of sight at a relatively low redshift (z <~0.1).
The issue is likely to be resolved by
Space Telescope observations later this year.
The next larger view is astrodeep200407aecc #30 (#24),
61 X 61 arc-sec :
[ astrodeep200407aecd # 25 is the same view, twice as dark ]
#30 (#24) field from Hubble Ultra Deep Field 832 X 833 p
tif 2.72 MB png 1.86 MB
This field is 61 sec wide = 1 minute wide.
RML-1 is the probable cosmic string gravitational lens,
the double blue spots just above the large magenta galaxy in the lower left.
There are six more suggestive blue spot pairs in this field.
Rich Murray Lens 1, closeup view in #21, is very like CSL-1,
only blue and more separated,
but with the tell-tell equality of size and color.
It turns out that there are so many easily found pairs of all sizes,
down to single pixel bright spots separated by a pixel space,
that statistical studies are appropriate.
Views # 20 to 29 will explore the HUDF, and provide many helpful links.
The colors have been adjusted to reveal a few faint distant red sources,
as well as a background of tiny blue sources, 1-2 pixel size,
which are always on the background of dark tangled Murray mesh --
easier to see at first behind the red light scattered inside the
Hubble Space Telescope by the much nearer bright star,
and also behind the large blue white galaxy in the upper right.
Click on All Sizes to view the Original.
I used an excellent low cost image processing program,
MGI PhotoSuite 4.0, to adjust the colors
to bring out the subtle background details:
Touchup feature: Soften: reduced from 3 to 0,
as I wanted to maximize the raw detail.
Color Adjustment: Cyan-Red +100 Magenta-Green +25 Yellow-Blue +50,
as empirically this created a pleasing,
easy to view image with maximum detail.
Brightness: increased from 0 to 50, to increase the dark background details.
Gamma: reduced from 1.00 to 0.80, to increase the dark background details.
Fix Colors: Hue: shifted 0 to -60,
to accentuate the background of myriad minute bright blue sources
without losing information from the red end of the spectrum.
www.aip.de/groups/galaxies/sw/udf/index.php# The UDF Skywalker
allows you to scan the entire HUDF with a movable magnifying glass
that shows about this scale of detail. You can discern Murray mesh with it.
www.damtp.cam.ac.uk/user/gr/public/cs_interact.html
Cosmic String Dynamics and Evolution
'After formation, an initially high density string network begins
to chop itself up by producing small loops. These loops oscillate rapidly
(relativistically) and decay away into gravitational waves.
The net result is that the strings become more and more dilute with time
as the universe expands.
From an enormous density at formation, mathematical modelling suggests
that today there would only be about 10 long strings stretching
across the observed universe, together with about a thousand small loops!
In fact the network dynamics is such that the string density will eventually
stabilize at an exactly constant level relative to the rest of the radiation
and matter energy density in the universe.
Thus the string evolution is described as `scaling' or scale-invariant,
that is, the properties of the network look the same at any particular
time t if they are scaled (or multiplied) by the change in the time.'
If you inspect this carefully, especially holding a 4 inch reading glass
close to both of your eyes, focussing on the tiny bright blue sources,
you will easily discern many suggestive pairs,
right down to the limit of two single pixel spots separated by a pixel,
or even the many double pixel spots.
The two sides of the convex reading glass function as opposed prisms,
separating the reds and blues in such a way as to make the reds appear
about a centimeter closer, creating a lovely, revealing 3D image,
while moving the glass back and forth can flexibly adjust
the smoothness and the sharpness of the image.
I found that using a 6"X5" concave glass, which in effect has prisms
opposed in the opposite direction of a convex lens,
makes a smaller overall image
in which the blues appear closer than the reds,
which I surmise is the actual reality
for these images for the background.
astrodeep200407aec # 23, 97.65 X 97.65" = 1.63 X 1.63'
#23 Part of bottom half of Hubble Ultra Deep Field,
255 X 255 pixels in the original HUDF,
[ cropped from its original 823 X 823 p when saved on
MGI PhotoSuite 4.0 as tif 112.618 MB ]
become 1911 X 1912 pixels in this expanded view,
tif 14.3 MB, uploaded as this png 9.83 MB,
just below the 10 MB Flickr limit.
Click on All Sizes to select Large and Original for much higher resolution.
The HUBF is described as 10,500 X 10,500 pixels,
at 0.03 arc-seconds/pixel,
giving a width of 315 arc-seconds = 5.25 arc-minutes,
oriented North at top and East to the left, with the center at
Right Ascension 03 hours 32 minutes 39.0 seconds
Declination -27 degrees 47 minutes 29.1 seconds
The previous photos #1-17 give the CSL-1 lens
and its subtle background in the Capodimonte Deep Field.
This field is 0.310 X 0.310 of the HUDF, 0.096 of its area,
the largest I could upload into Flickr. 97.65 X 97.65" = 1.63 X 1.63'
The 1-2 mm red and blue sources are much closer galaxies,
with their apparent colors determined by their actual temperature
and the amount of redshifting, which grows linearly with distance.
Much nearer to us, of course are the three 1-5 cm galaxies,
while the lower left red star is very much closer, in our own galaxy.
astrodeep200407aea # 20, the same view,
with the color settings of the public HUDF,
a freely available 110 MB TIFF image:
'In this image, blue and green correspond to colors that can be seen
by the human eye, such as hot, young, blue stars
and the glow of Sun-like stars in the disks of galaxies.
Red represents near-infrared light, which is invisible to the human eye,
such as the red glow of dust-enshrouded galaxies.'
hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
highest resolution available public image 6200 X 6200 pixels TIFF 109.99 MB
#20 Part of bottom half of Hubble Ultra Deep Field,
255 X 255 pixels in the original HUDF,
[ cropped from its original 823 X 823 p
when saved on MGI PhotoSuite 4.0 as tif 112.618 MB ]
become 1911 X 1912 pixels in this expanded view, tif 14.3 MB,
uploaded as this png 9.83 MB, just below the 10 MB Flickr limit.
Click on All Sizes to select Large and Original for much higher resolution.
RML-1 is a tiny bright blue galaxy pair
just above the large yellow galaxy by the lower left edge.
Rich Murray Lens 1, closeup view in #21, is very like CSL-1,
only blue and more separated,
but with the tell-tell equality of size and color.
It turns out that there are so many easily found pairs of all sizes,
down to single pixel bright spots separated by a pixel space,
that statistical studies are appropriate.
Views # 20 to 29 will explore the HUDF, and provide many helpful links.
The previous photos #1-17 give the CSL-1 lens and its subtle background
in the Capodimonte Deep Field.
This field is 0.310 X 0.310 of the HUDF, 0.096 of its area,
the largest I could upload into Flickr. 97.65 X 97.65" = 1.63 X 1.63'
http://hubblesite.org/newscenter/newsdesk/archive/releases/
2004/07/text/">hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
Hubble's Deepest View Ever of the Universe Unveils Earliest Galaxies
Release date: 2004.03.09 Images made 2003.09.24 -- 2004.01.16
'In this image, blue and green correspond to colors that can be seen
by the human eye, such as hot, young, blue stars
and the glow of Sun-like stars in the disks of galaxies.
Red represents near-infrared light, which is invisible to the human eye,
such as the red glow of dust-enshrouded galaxies.'
hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
highest resolution available public image 6200 X 6200 pixels TIFF 109.99 MB
hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
The Large view of the HUDF is a JPG size .0681 MB,
which shows RML-1 as a blue dot.
Enlarging it gives a 4 X 4 p white grey object
that has only a hint of something to its right.
hubblesite.org/newscenter/newsdesk/archive/releases/2004/...
This gives a fine TIFF view from HUDF of the RML-1 field,
a little smaller than my view here, 2.87 MB,
saved on my computer as a tif 2.942 MB.
A closeup of RML-1 in their view clearly shows a double galaxy,
with the L side slightly larger, about 12 X 12 pixels maximum,
and a brighter core of about 6 X 6 pixels: blue, green, brown.
Click on All Sizes to view Large and Original.
Notice the many bright blue pairs, and in Original the background haze
of myriad tiny blue spots, which I call Bright Blue Blazers,
with many pairs of BBB.
If you hold a 4 inch reading glass close to your face
and look through it with both eyes closely
at the monitor screen or a color print,
with the background lights turned off in your room,
you will see the different colors separated out as an apparent 3D image
about a centimeter deep, with red spots closer and the BBB in back,
against a 3D fractile network of tangled dark filaments.
Look close to the bright yellow-red star and the large blue-white galaxy
to see the dark background filaments.
The galaxy has many blue clumps inside it,
indicating that it grew by absorbing many blue dwarf galaxies.
xxx.lanl.gov/PS_cache/astro-ph/pdf/0504/0504032.pdf
arXiv:astro-ph/0504032 v1 1 Apr 2005 Stellar Populations in Galaxies
*************************************************************
From: "Malcolm Fairbairn" malc@physto.se
To: "Rich Murray" rmforall@comcast.net
Subject: Re: more candidate cosmic string lens pairs in HUDF
(re comment by Levon Pogosian on astro-ph/0506400);
also myriad minute bright blue sources, always on dark background mesh:
Murray 2005.11.10
Date: Friday, November 11, 2005 2:38 AM
Hello Rich Murray,
I don't have time to look in detail at all your information, so I'll focus
on one little point, apologies.
Regarding the image on your website page
http://www.flickr.com/photos/rmforall/19726818/astrodeep200407aecd ,
where you claim to identify cosmic string lens candidates
in the Hubble deep field.
The reason why CSL-1 a is compelling is because we have spectra for
both images.
However, if there is a cosmic string then it will give rise to lensing
with a specific angle.
Do you know the angular separation of the objects or their redshifts?
best, Malcolm
--------------------------------------------------
http://www.physto.se/~malc/
Cosmology, Particle astrophysics and String theory
Department of Physics Stockholm University
AlbaNova University Center SE-106 91 Stockholm
Sweden Telephone +46 8 55 37 87 30
--------------------------------------------------
*************************************************************
http://arxiv.org/PS_cache/astro-ph/pdf/0511/0511085.pdf
arXiv:astro-ph/0511085 v2 3 Nov 2005
CSL-1: Lensing by a Cosmic String or a Dark Matter Filament?
Malcolm Fairbairn malc@physto.se
Cosmology, Particle astrophysics and String theory, Department of Physics,
Stockholm University,
AlbaNova University Centre, SE-106 91, Stockholm, Sweden
The lens candidate CSL-1 has been interpreted
as evidence for a cosmic string.
Here we test the hypothesis that the lensing comes
from a tidally disrupted dark matter halo.
We calculate the mass-density relationship
that one would expect from structure formation theory
and come to the conclusion
that in order to explain the lensing using dark matter,
the halo would have to have a mass greater than the Milky Way.
There is apparently no such object seen in the data.
If the follow up observations confirm that the two objects
are indeed images of the same galaxy, then it seems
difficult to explain the lens using dark matter.
*************************************************************
ten clump-cluster galaxies in Hubble Ultra Deep Field, BG & DM Elmegreen
2005.04.01
arXiv: astro-ph/0504032 v1 1 Apr 2005
Stellar Populations in Ten Clump-Cluster Galaxies of the Ultra Deep Field
Bruce G. Elmegreen
IBM Research Division, T.J. Watson Research Center, P.O. Box 218,
Yorktown Heights, NY 10598, USA, bge@...
Debra Meloy Elmegreen
Vassar College, Dept. of Physics & Astronomy, Box 745, Poughkeepsie, NY
12604; elmegreen@...
ABSTRACT
Color-color diagrams for the clump and interclump emission in 10
clump-cluster galaxies of the Ultra Deep Field are made from B,V,i, and z
images and compared with models to determine redshifts,
star formation histories, and galaxy masses.
These galaxies are members of a class dominated by 5 to 10 giant clumps,
and having no exponential disk or bulge.
The redshifts are found to be in the range from 1.6 to 3.
The clump emission is typically 40% of the total galaxy emission and the
luminous clump mass is 19% of the total galaxy mass.
The clump colors suggest declining star formation over the last ~0.3 Gy,
while the interclump emission is redder than the clumps,
corresponding to a greater age.
The clump luminous masses are typically 6 × 10E8 M(Sun) and their diameters
average 1.8 kpc, making their average density ~0.2 M(Sun) pc-3.
Including the interclump populations, assumed to begin forming at z = 6,
the total galaxy luminous masses average 6.5 × 10E10 M(Sun)
and their diameters average 19 kpc to the 2 sigma noise level.
The expected galaxy rotation speeds average ~150 km s-1 if they are
uniformly rotating disks.
The ages of the clumps are longer than their internal dynamical times by a
factor of ~8, so they are stable star clusters,
but the clump densities are only ~10 times the limiting tidal densities,
so they could be deformed by tidal forces.
This is consistent with the observation that some clumps have tails.
The clumps could form by gravitational instabilities in accreting disk gas
and then disperse on a ~1 Gy time scale,
building up the interclump disk emission,
or they could be captured as gas-rich dwarf galaxies,
flaring up with star formation at first and then dispersing.
Support for this second possibility comes from the high abundance of nearly
identical clumps in the UDF field, smaller than 6 pixels, whose
distributions on color-magnitude and color-color plots are the same as the
galaxy clumps studied here.
The distribution of axial ratios for the combined population of chain and
clump-cluster galaxies in the UDF is compared with models and shown to be
consistent with a thick disk geometry.
If these galaxies evolve into today's disk galaxies, then we are observing a
stage where accretion and star formation are extremely clumpy and the
resulting high velocity dispersions form thick-disks.
Several clump-clusters have disk densities that are much larger than in
local disks, however, suggesting an alternate model where they do not
survive until today, but get converted into ellipticals by collisions.
Subject headings: galaxies: formation - galaxies: evolution - galaxies: high
red-shift - galaxies: irregular
*************************************************************
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