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Post Info TOPIC: Hubble Ultra Deep Field


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ALMA Explores the Hubble Ultra Deep Field

International teams of astronomers have used the Atacama Large Millimeter/submillimeter Array (ALMA) to explore the distant corner of the Universe first revealed in the iconic images of the Hubble Ultra Deep Field (HUDF). These new ALMA observations are significantly deeper and sharper than previous surveys at millimetre wavelengths. They clearly show how the rate of star formation in young galaxies is closely related to their total mass in stars. They also trace the previously unknown abundance of star-forming gas at different points in time, providing new insights into the "Golden Age" of galaxy formation approximately 10 billion years ago.
The new ALMA results will be published in a series of papers appearing in the Astrophysical Journal and Monthly Notices of the Royal Astronomical Society. These results are also among those being presented this week at the Half a Decade of ALMA conference in Palm Springs, California, USA.

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Title: Serendipitous discovery of a massive cD galaxy at z=1.096: Implications for the early formation and late evolution of cD galaxies
Authors: F. S. Liu, Yicheng Guo, David C. Koo, Jonathan R. Trump, Guillermo Barro, Hassen Yesuf, S. M. Faber, M. Giavalisco, P. Cassata, A. M. Koekemoer, L. Pentericci, M. Castellano, Edmond Cheung, Shude Mao, X. Y. Xia, Norman A. Grogin, Nimish P. Hathi, Kuang-Han Huang, Dale Kocevski, Elizabeth J. McGrath, Stijn Wuyts

We have made a serendipitous discovery of a massive cD galaxy at z=1.096 in a candidate rich cluster in the HUDF area of GOODS-South. This brightest cluster galaxy is the most distant cD galaxy confirmed to date. Ultra-deep HST/WFC3 images reveal an extended envelope starting from ~10 kpc and reaching ~70 kpc in radius along the semi-major axis. The spectral energy distributions indicate that both its inner component and outer envelope are composed of an old, passively-evolving stellar population. The cD galaxy lies on the same mass-size relation as the bulk of quiescent galaxies at similar redshifts. The cD galaxy has a higher stellar mass surface density but a similar velocity dispersion to those of more-massive, nearby cDs. If the cD galaxy is one of the progenitors of today's more massive cDs, its size and stellar mass have had to increase on average by factors of 3.4±1.1 and 3.3±1.3 over the past ~8 Gyrs, respectively. Such increases in size and stellar mass without being accompanied by significant increases in velocity dispersion are consistent with evolutionary scenarios driven by both major and minor dry mergers. If such cD envelopes originate from dry mergers, our discovery of even one example proves that some BCGs entered the dry merger phase at epochs earlier than z=1. Our data match theoretical models which predict that the continuance of dry mergers at z<1 can result in structures similar to those of massive cD galaxies seen today. Moreover, our discovery is a surprise given that the extreme depth of the HUDF is essential to reveal such an extended cD envelope at z>1 and, yet, the HUDF covers only a minuscule region of sky. Adding that cDs are rare, Our serendipitous discovery hints that such cDs may be more common than expected.

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Hubble census finds galaxies at redshifts 9 to 12

Astronomers using the NASA/ESA Hubble Space Telescope have uncovered seven primitive galaxies from a distant population that formed more than 13 billion years ago. In the process, their observations have put forward a candidate for the record for the most distant galaxy found to date (at redshift 11.9), and have shed new light on the earliest years of cosmic history. The galaxies are seen as they were when the Universe was less than 4 percent of its present age.
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Hubble Ultra Deep Field 2012
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Hubble Provides First Census of Galaxies Near Cosmic Dawn

Using NASA's Hubble Space Telescope, astronomers have uncovered a previously unseen population of seven primitive galaxies that formed more than 13 billion years ago, when the universe was less than 3 percent of its present age. The deepest images to date from Hubble yield the first statistically robust sample of galaxies that tells how abundant they were close to the era when galaxies first formed. The results show a smooth decline in the number of galaxies with increasing look-back time to about 450 million years after the big bang. The observations support the idea that galaxies assembled continuously over time and also may have provided enough radiation to reheat, or reionise, the universe a few hundred million years after the big bang.
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Title: The 2012 Hubble Ultra Deep Field (UDF12): Observational Overview
Authors: Anton M. Koekemoer, Richard S Ellis, Ross J. McLure, James S. Dunlop, Brant E Robertson, Yoshiaki Ono, Matthew A. Schenker, Masami Ouchi, Rebecca A. A. Bowler, Alexander B. Rogers, Emma Curtis-Lake, Evan Schneider, Stephane Charlot, Daniel P. Stark, Steven R. Furlanetto, Michele Cirasuolo, V. Wild, T. Targett

We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128-orbit Cycle 19 HST program aimed at extending previous WFC3/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an additional F140W filter, and extending the F160W exposure time by 50%. The principal scientific goal of this project is to determine whether galaxies Reionised the universe; our observations are designed to provide a robust determination of the star formation density at z\gtrsim8, improve measurements of the ultraviolet continuum slope at z~7-8, facilitate the construction of new samples of z~9-10 candidates, and enable the detection of sources up to z~12. For this project we committed to combining these and other WFC3/IR imaging observations of the UDF area into a single homogeneous dataset, to provide the deepest near-infrared observations of the sky currently achievable. In this paper we present the observational overview of the project, motivated by its scientific goals, and describe the procedures used in reducing the data as well as the final products that are produced. We have used the most up up-to-date methods for calibrating and combining the images, in particular paying attention to correcting several instrumental effects. We release the full combined mosaics, comprising a single, unified set of mosaics of the UDF, providing the deepest near-infrared blank-field view of the universe obtained to date, reaching magnitudes as deep as AB~30 in the near-infrared, and yielding a legacy dataset on this field of lasting scientific value to the community.

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Title: The Tumultuous Formation of the Hubble Sequence at z > 1 Examined with HST/WFC3 Observations of the Hubble Ultra Deep Field
Authors: C. J. Conselice, A.F.L. Bluck, S. Ravindranath, A. Mortlock, A. Koekemoer, F. Buitrago, R. Grützbauch, S. Penny

We examine in this paper a stellar mass selected sample of galaxies at 1 < z < 3 within the Hubble Ultra Deep Field, utilising WFC3 imaging to study the rest-frame optical morphological distribution of galaxies at this epoch. We measure how apparent morphologies (disk, elliptical, peculiar) correlate with physical properties, such as quantitative structure and spectral-types. One primary result is that apparent morphology does not correlate strongly with stellar populations, nor with galaxy structure at this epoch, suggesting a chaotic formation history for Hubble types at z > 1. By using a locally defined definition of disk and elliptical galaxies based on structure and spectral-type, we find no true ellipticals at z > 2, and a fraction of 3.2±2.3% at 1.5 < z < 2. Local counterparts of disk galaxies are at a similar level of 7-10%, much lower than the 75% fraction at lower redshifts. We further compare WFC3 images with the rest-frame UV view of galaxies from ACS imaging, showing that galaxies imaged with ACS that appear peculiar often contain an 'elliptical' like morphology in WFC3. We show through several simulations that this larger fraction of elliptical-like galaxies is partially due to the courser PSF of WFC3, and that the 'elliptical' class very likely includes early-type disks. We also measure the merger history for our sample using CAS parameters, finding a redshift evolution increasing with redshift, and a peak merger fraction of ~30% at z~2 for the most massive galaxies with M_*> 10^{10} M_sol, consistent with previous results from ACS and NICMOS. We compare our results to semi-analytical model results and find a relatively good agreement between our morphological break-down and the predictions. Finally, we argue that the peculiars, ellipticals and peculiar ellipticals have similar properties, suggesting similar formation modes, likely driven by major mergers.

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70 enhanced color and gamma public HUDF views, 1 -- 20 MB at rmforall at Flickr.com
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70 enhanced color and gamma public HUDF views, 1 -- 20 MB at rmforall at Flickr.com

I've been putting them up since 2005 -- viewed by over 10,000.

They may each be viewed at different scales, and, being public domain, are freely downloadable.

Colors have been shifted and enhanced, and gamma raised from 1 to 2 or 3, to bring out subtle details on all scales, in views from a few percent to 100 percent of the HUDF, including 8 20 MB rectangles that cover the entire field in png format.

I think many fundamental discoveries await anyone who takes some time to gaze open mindedly into them.

It really helps to use a 24" monitor or project onto a large screen -- their appearance varies a lot from computer to computer, or from laptop view to larger.
I've shown them projected onto 10X10' screens to groups. The computer visual display can be easily adjusted to find the most revealing settings.

I've copied out many research reports to accompany the photos.

I describe how and what I discern, and welcome critical sharing in the spirit of genteel rational discussion on specific facts and observations to develop shared understandings for the common welfare.

HUDF center top left, #90 astrodeep200407aab10ada.png 3.68 MB 1244X1243 1 of 4 identical views with different color schemes 2008.12.12 #88-91 on rmforall at flickr.com: Rich Murray 2011.01.09
http://rmforall.blogspot.com/2011_01_01_archive.htm
Sunday, January 9, 2011[ at end of each long page, click on Older Posts ]
http://groups.yahoo.com/group/astrodeep/message/80
[you may have to Copy and Paste URLs into your browser]
____________________________________________________________

for viewing -- click on Actions to get different sizes and for free download

http://www.flickr.com/photos/rmforall/3103426063/in/photostream/

#89 astrodeep200407aab10aea.png 4.14 MB 1244X1283 HUDF center top left

This image is 6.3x6.3 arc-seconds, 3.965% of the area of the Hubble Ultra Deep Field,

which is 186 arc-seconds wide and high = 3.1 arc-minutes

= 1/10 width of the Full Moon or Sun, about 0.5 degrees,

so the HUDF is about 1% of the area of the square that holds the Full Moon or Sun,

short introduction re viewing lovely subtle earliest structures in HUDF: AstroDeep, Rich Murray 2009.02.23

I've found since 2005 myriad ubiquitous bright blue sources, always on a darker fractal 3D web, along with a variety of sizes of irregular early galaxies, in the Hubble Ultra Deep Field, simply by increasing the gamma from 1.00 to 2.00 and saturating the colors, while minimizing the green band to simplify the complex overlays of complex fractal structures.

Dozens of these images, covering the entire HUDF in eight ~20 MB segments, are available for viewing at many scales [ To change the size of images on Windows PCs, use Control - and + ] on www.Flickr.com at the "rmforall" photostream. Try #86 for the central 16% of the HUDF.

ubiquitous bright blue 1-12 pixel sources on darker 3D fractal web in five 2007.09.06 IR and visible light HUDF images, Nor Pirzkal, Sangeeta Malhotra, James E Rhoads, Chun Xu, -- might be clusters of earliest hypernovae in recent cosmological simulations: Rich Murray 2008.08.17 2009.01.20
rmforall.blogspot.com/2008_08_01_archive.htm
Sunday, August 17, 2008
groups.yahoo.com/group/AstroDeep/25
groups.yahoo.com/group/rmforall/85

www.flickr.com/photos/rmforall/1349101458/in/photostream/

The 5 closeups are about 2.2x2.2 arc-seconds wide and high, about 70x70 pixels.
The HUDF is 315x315 arc-seconds, with N at top and E at left.
Each side has 10,500x10,500 pixels at 0.03 arc-second per pixel.

Click on All Sizes and select Original to view the highest resolution image of 3022x2496 pixels, which can be also be conveniently seen directly at their Zoomable image:

www.spacetelescope.org/images/html/zoomable/heic0714a.html

Notable in the deep background of the five closeups are ubiquitous bright blue sources, presumably extremely hot ultraviolet before redshifting, 1 to a dozen or so pixels, as single or short lines of spots, and a few irregular tiny blobs, probably, as predicted in many recent simulations, the earliest massive, short-lived hypernovae, GRBs with jets at various angles to our line of sight, expanding bubbles, earliest molecular and dust clouds with light echoes and bursts of star formation, and first small dwarf galaxies, always associated with a subtle darker 3D random fractal mesh of filaments of H and He atomic gases.

As a scientific layman, I am grateful for specific cogent, civil feedback, based on the details readily visible in images in the public domain.

www.spacetelescope.org/images/html/heic0714a.html

Hubble and Spitzer Uncover Smallest Galaxy Building Blocks

Rich Murray, MA Room For All rmforall@gmail.com 505-819-7388
1943 Otowi Road, Santa Fe, New Mexico 87505
groups.yahoo.com/group/rmforall/messages
groups.yahoo.com/group/AstroDeep/messages
www.sfcomplex.org Santa Fe Complex

You are welcome to visit me and share your comments as I share these images at home on a 4X8 foot screen -- no fee.

Anyone may view and download for free 91 images, presenting the HUDF in eight 20 MB pieces at rmforall at www.FlickR.com -- #86 is about 20% of the HUDF in their red and blue colors, as leaving out the green greatly simplifies interpreting the overlapping layers of transparent fractal webs of gas with a wide range of sizes of rather distant sources, beyond z = 5.







-- Edited by Rich Murray on Friday 21st of January 2011 04:08:02 AM

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Using the recently updated Hubble Space Telescope (HST) two teams of UK astronomers have identified galaxies which are likely to be the most distant yet seen.
The UK teams, one led by Andrew Bunker and Stephen Wilkins at the University of Oxford and the other by Ross McLure and Jim Dunlop at the University of Edinburgh, analysed infrared images from the new Wide Field Camera 3 (WFC3) instrument on the HST, installed during the most recent Space Shuttle servicing mission in May 2009.

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An amazing video about the Hubble Deep Field, ending with a fly-through of its representation in 3D, rendered using the measured redshift of the picture.

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