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Posts Tagged ‘Cosmic Frontier’

The cleanup of the MINOS cavern and the rest of the Soudan Underground Laboratory is complete.

This article first appeared in

Fermilab Today May 25.

Two months after a fire broke out in the access shaft of the Soudan mine, the Soudan Underground Laboratory is again open for operation. Safety officers inspected the mine and laboratory last week and issued a permit for normal occupancy. The officers identified a short list of additional repairs, which will be carried out in the upcoming months. Work also continues on the Soudan mine shaft.

“The cleanup of the laboratory is complete, and the MINOS far detector is ready to take beam data with full magnetic field,” said Fermilab physicist Rob Plunkett, co-spokesperson for the MINOS neutrino experiment. “The small number of components we had to replace was consistent with a normal power outage.”

The 5,000-ton MINOS far detector is located a half mile underground in the Soudan laboratory. In March, fire-fighting foam covered parts of the detector and the lowest part of the magnet coil was partially immersed in water. Laboratory staff gently heated the coil over the past two weeks to dry it out.

The CDMS experiment, located in a cavern adjacent to the MINOS detector, experienced no damage to its equipment except to a backup generator. Its cryogenic system recovered unscathed from the power outage triggered by the fire. CDMS scientists have removed the new particle detectors they were testing before the fire, and they will begin operation of an expanded experiment with more dark-matter detectors in September.

University of Minnesota building code inspectors and ES&H personnel from the university and Fermilab inspected the laboratory last Wednesday. The University of Minnesota manages the Soudan Underground Laboratory.

— Kurt Riesselmann

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Editor’s note: Bob’s most excellent particle detector adventure, part 8.

Bob Peterson continues to travel with his QuarkNet particle detector around the edge of Africa recording remnants of cosmic rays. This offers a chance to study how cosmic ray recordings differ on land and sea and at different latitudes. The data will be accessible to high school students and teachers in several countries who use similar detectors to learn about particle physics.

Read his previous posts here: The voyage begins, Turning the detector on, Other science on the sea, Particle detectors don’t like light, Enduring a branding for science A teaching moment on the ocean, Using ballons to study the sky to help IceCube and QuarkNet.

14 May 2011
R/V Polarstern
Latitude: 40-22.8 N
Longitude: 11-22.4 W
off the Portugal coast
Ship course 009° T
Ship velocity 7 knots

12 May:
The Polarstern plans a stop in the middle of nowhere for 24 hours. The ship is conducting a bottom survey using new echo-sounding hardware and new software to “paint the picture”. The scientists have chosen a sea mount that rises from 5,000 meter, or 3 mile, depth to 57 meter, or a little more than one-quarter of a mile. There’s a damn big mountain out here. Funny, the top looks just the same: flat with few waves. The ship will run a survey course that looks like a search and rescue pattern; back and forth runs the ship across the sea mount. Frustrating to those sunning on deck; they have to keep switching sides.

Clearly, the fishermen know about the rise. They are out here in numbers setting their nets.

By the way, several birds have hitched a ride. They try to escape, but don’t go far before returning. How did they get here if there is nowhere to go?

14 May:
Just as Max, the weather forecaster predicted the Force 8 gale arrived in the middle of the night. That meant winds of 39 to 45 mph and moderate waves with lots of spray. Good. I wanted a good Atlantic Ocean storm before the
voyage was over; I got a doosey.

Looking out the weather-office window, I stand 55 feet off the water. Spray passes me by and the waves look, oh,
20 to 25 feet tall. It’s blowin’ 40 knots and Max thinks it will increase to 45-50 knots. I haven’t seen this in 30 years. The ship is literally “pounding into the teeth of it”. Hmmmm, where is everyone for breakfast? I’m doing fine after three weeks to acclimate to the rolling boat.

Overnight I seized on extra lashings for the cosmic ray muon detector (CRMD) to keep the hardware on the table, and it continues to count those cosmic rays. The muons don’t seem to have retreated to their bunks. My mantra is “take that data”. Though typpimtntg is a bit difgucilt. This blog installment will be short.

Maybe, I will go to my bunk after all.

Glossary
*Knot: A nautical term for miles per hour.10 knots equals12 mph.

–Bob Peterson

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Editor’s Note:  Fermilab is getting ready for its annual meeting that draws together many of the 2,311 scientists across the U.S. and globe that work with Fermilab as well as staff physicists and engineers. While it could be a time of sadness and reflection with the Tevatron set to shutdown, physicists are finding that Fermilab still has a lot to offer in terms of exciting, ground-breaking science as Fermilab Director Pier Oddone outlines in his weekly column.

This article first appeared in Fermilab Today May 24.

The 44th edition of the Users’ Meeting will take place on June 1 and 2, and it should be very exciting. The Users’ Meeting is a well-established tradition at Fermilab. Every year it showcases results from the entire Fermilab experimental program, alongside discussions of the lab’s future program and presentations from government officials about policies applicable to particle physics. This year we are very fortunate to have the Secretary of Energy, Dr. Steven Chu, presenting the Meeting’s public lecture at 8 p.m. on June 2.

This year has a special edge as we approach the end of data collection at the Tevatron. This remarkable machine is achieving luminosities considered impossible decades ago with antiprotons — more than 4 x 1032 cm-2sec-1 instantaneous luminosity, with 11 femtobarns of accumulated luminosity recently celebrated.

The Tevatron’s two international collaborations CDF and DZero have many achievements of their own, including major discoveries that have established our Standard Model of particle physics. There is still juice left in the Tevatron and we may yet establish processes beyond the Standard Model if some of the collaborations’ recent results are confirmed. We also have hints of unexpected results in the neutrino sector, with neutrino oscillation data from MiniBooNE and MINOS.

Looking to the future, MINERvA is laying the foundation for understanding different nuclear targets, NOvA construction is proceeding well, and there are new proposals to extend MINOS running. The Dark Energy Survey is nearing completion, better detectors are in development for the Cryogenic Dark Matter Search, and the COUPP dark matter search is operating a small prototype at Sudbury and a larger 60 kg prototype in the NuMI tunnel. Pierre Auger continues to provide interesting results with ultra-high-energy cosmic rays. And the LHC is working splendidly and results are coming out at a fast pace.

We are also in a critical year for two long-term projects, LBNE and Project X. In addition to Project X’s broad Intensity Frontier physics program, it can serve as a foundation for a neutrino factory if one is needed to fully understand the physics of neutrinos. Looking even farther ahead, we are studying the feasibility of muon colliders as a path back to the Energy Frontier.
All this activity augurs a great Users’ Meeting next week.

–Pier Oddone, Fermilab director

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 Editor’s note:
Bob’s most excellent particle detector adventure, part 4.

 Bob Peterson continues to travel with his QuarkNet particle detector around the edge of Africa recording remnants of cosmic rays. This offers a chance to study how cosmic ray recordings differ on land and sea and at different latitudes. The data will be accessible to high school students and teachers in several countries who use similar detectors to learn about particle physics.  

Read his previous posts here:
*The voyage begins

*Turning the detector on

*Other science on the sea

 27 April 2011
R/V Polarstern
Latitude: 11-15.6 S
Longitude: 2-13.2 W
Ship velocity 10.9 knots
Ship course 322.9 ° T

Progressively, over the last three days, the data from the cosmic ray muon detector has become more problematic.

How a QuarkNet detector reads a cosmic ray remenant. Credit: Fermilab/QuarkNet

Here’s how our system works. Plastic scintillator is covered with aluminum foil and then with black paper and tape to make it “light-tight.” Any light leaking in will incorrectly be recorded as a particle interaction and make the data unreliable. A photo multiplier tube, or PMT, is attached to the wrapped scintillator; this assembly is called a counter. Up to four of these can be connected to the data acquisition card. The data acquisition system, or DAQ, sends data to the computer via the USB port. When a cosmic ray muon passes through the scintillator it causes a few photons to be emitted in the scintillator material. These are picked up by the photo multiplier tube, converted to an electrical pulse and amplified. Each photo multiplier tube sends its signal to the data acquisition system.

It is not working like that today.

One of the counter channels has become variable; first rising in counts and then falling. We look for what we call coincidences, two signals, one from each photo multiplier tube, received within a short time. These are reported to the computer; all other signals are vetoed as likely background noise from the photo multiplier tubes

I have been seeing far fewer coincidences than the data acquisition system should be recording. This has affected the overall data flow, causing it sometimes to fall to zero.

Looking back over the several days, I seemed to notice a day/night dependency. So, I decided to disassemble the counter “stack” and see if there was a possible light leak in the fourth counter; of course, that was the bottom counter. Sure enough, the bottom counter had been poorly assembled and much of the wrapping tape had let go and opened several “seams”. There were not major gaps, but they were large enough to let light leak into the photo multiplier tubes. I’m glad I found this out. I inspected all the counters and found a few other suspect areas.

QuarkNet cosmic ray muon detector tool kit. Credit: Fermilab

With the gaps addressed, the detector is back on the air and the data looks healthy.

Meanwhile, the Polarstern progresses north and west. The weather is now warm and sticky with humidity. We approach the Inter Tropical Convergence Zone where the global circulation cells collide causing an upwelling of air. Showers can be expected in a day or two.

Also, expected is the equator. When we cross over, the “pollywogs”, or people who have never crossed the equator, will be “baptized” by Neptune. I’ve been warned to wear old clothes and be prepared to throw them away. I suppose I really can’t be considered a sailor ’til I submit.

Wonder if I should get an earring? What do you think?

— Bob Peterson

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Editor’s note:
Bob’s most excellent particle adventure, part 3

Bob Peterson continues to travel with his QuarkNet particle detector around the edge of Africa recording remnants of cosmic rays. This offers a chance to study how cosmic ray recordings differ on land and sea and at different latitudes. The data will be accessible to high school students and teachers in several countries who use similar detectors to learn about particle physics.

His first post explains why he’s taking his science to the seas and how getting a detector on a boat sounds easier than it is.  In Bob’s second post the boat gets going and so does the detector.

26 April 2011
R/V Polarstern
Lat: 13-40.8 S
Long: 0-8.6 W
Ship velocity 11.0 knots
Ship course 322.7 ° T

After six days out, we just crossed back to the Western Hemisphere. I wondered what that bump was. Home still feels a long way away. The first days of the heavy swell have passed and everyone, including myself, is resting easier. The voyage has started to focus on the science to be done.

However, every onboard science group is experiencing problems with data collection including myself and the QuarkNet cosmic ray muon detector. After a successful plateauing while in Cape Town, South Africa, now one data channel is acting up with changeable counts of cosmic ray remnants interacting with the detector. The rate on that one channel will rise and fall unexpectedly and I cannot find a cause. It’s happened over the past two nights. If it happens again, I will switch the power cables and see if I can isolate the cause.

It occurred to me that anything done on a ship complicates procedures. Ship environments do not make data collection easy. There is constant motion from swell and wind, and this slows just putting hardware together. Tools are not close at hand, and if ship personnel get involved, then the chain of command comes into play. And to search for anything means climbing flights of stairs. My legs are getting stronger, but the stairs are so steep that I tread carefully. Ship personnel go up and especially down like cats.

One group from the Leibniz Institute of Tropospheric Research has two large containers bolted to the top deck over the bridge. This deck is 85 feet above the water. Extending out the forward side of one container is an intake pipe that is “sniffing” the air in the lower atmosphere for particles. Not high-energy particles, rather things such as soot and sea salt and organic compounds. They need to avoid any ship-generated contaminates as they are trying to correlate the low-level atmospheric particles with the upper atmosphere. The upper atmosphere is measured using a Light Detection and Ranging, or LIDAR, laser system from the second container. So, at night you can see a rich green laser projecting vertically over the ship. Well, we are sailing in the southeast trade winds and our heading is due northwest so the relative wind over the deck is from the stern. Unfortunately, they are “sniffing” the engine exhaust coming out of the stack, and they can even tell when the galley starts cooking. Their sampling is so accurate that they can tell what is for dinner. I can tell what’s for dinner by reading the menu.

Glossary:

Plateauing a detector: This means that the detector has hit the sweet spot where the photo multiplier tubes are recording the optimal amount of photons. Below that spot we would be missing valuable data and above it the data would get muddy.

*Stern: The rearmost part of a ship or boat.

*Trade winds: A wind blowing steadily toward the equator from the northeast in the Northern Hemisphere or the southeast in the Southern Hemisphere, especially at sea. Two belts of trade winds encircle the Earth, blowing from the tropical high-pressure belts to the low-pressure zone at the equator.

*Stack: A chimney or a vertical exhaust pipe.

— Bob Peterson

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Bob Peterson continues to travel with his QuarkNet  particle detector around the edge of Africa recording remnants of cosmic rays. This offers a chance to study how cosmic ray recordings differ on land and sea and at different latitudes. The data will be accessible to high school students and teachers in several countries who use similar detectors to learn about particle physics.

 
His first post explains why he’s taking his science to the seas and how getting a detector on a boat sounds easier than it is.

–April 20: Breakfast at 0730 and you better be on time. The galley crew frowns on late comers and they clear the tables whether you are done or not. Other scientists have boarded in preparation of our departure. There is a group of atmospheric chemists studying particles that nucleate clouds. They had a gigantic shipping container lifted aboard last night, and spent the night setting up. They look a bit bedraggled. Soon, I will be too. I want to get the detector on the air before we depart. But, still, the cosmic ray muon detector sits on the cargo deck and I can’t carry it up seven flights of stairs.

Cosmic ray muon detector aboard ship. Credit: Fermilab

–April 20, 1200: It’s noon and finally the cosmic ray muon detector (in a box) is sitting in front of the ship’s weather office. My contact, Michael Walter, from the high-energy physics laboratory DESY/Zeuthen in Germany,  does outreach with students using cosmic ray detectors and is a collaborator on IceCube. He  previously installed his own detector. My detector will live directly above. By having two detectors of the same type we can double check data and also have a backup for when one of the detectors malfunction, which has happened at times on previous trips. The afternoon will be busy: assemble, plateau, capture data, record data.

–April 20, 1950: Didn’t quite make collecting data. The cosmic ray muon detector is alive and healthy and all counters plateaued. That means that the detector has hit the sweet spot where the photo multiplier tubes are recording the optimal amount of photons. Below that spot we would be missing valuable data and above it the data would get muddy. While all this is great, I lack a computer to record data. I need drivers installed to talk to the data acquisition system, and the computer I’m using doesn’t have drivers. No driver; no data recorded. I must have the data. I will work on this problem
tomorrow.
Right now, the pilot has arrived to shepherd the R/V Polarstern out of Cape Town and underway. I will hide in the dark corners of the bridge and stay out from under foot.

— April 20, 2001: Much is going on. The gangway has been taken in, the springs are loosed and weare headed north and west. The pilot departs with the briefest of words. It’s dark and the Southern Cross constellation  is rising in the east; Orion is settling in the west. We clear the breakwater at 2020, and, oh my, what a westerly swell. The weather officer warned me: Be ready. I am not, and my stomach rolls over. It’s been 30 years since I have felt such a thing, and I’m as green as the wreaths of Christmas. It’s going to be an unpleasant night. Quickly I retire to my bunk.

–April 21AM: The Polarstern is a big ship, but it is getting pushed around by 6-to 8-meter swells. After all we are near the roaring forties winds and the dominate westerlies. The weather guys have quickly become my friends as they point out that this will pass soon enough as we enter the southeast trade winds.
But, I can’t wait. I have to get that cosmic ray muon detector data recorded no matter my condition. If you need friends, look to your weathermen, named Klaus and Max, and your systems administrator, named Felix. Installing the driver has proven problematic for the available Ubuntu machine. Felix enters with a brand new Mac: “Can you use this?” Within minutes, I have data sliding neatly into the open file, and now I can relax. Back to my bunk where I will spend the afternoon.

–April 21 PM: Klaus was right. Slowly the swell subsided and so did my constitution. I managed to attend dinner and felt better. Not great; just better. More good news: the cosmic ray muon detector is behaving.

— April 23: I’m managing many things now. I’ve figured out the meal schedule. I’ve learned who to go to with questions: Klaus and Max and Felix are always willing but steer clear of the cargo mate. He’d just as soon bite your head off. I’m always welcome on the bridge and Philipp is good at providing details. I know much of this, though I’m a bit rusty. It’s all coming back. And still the cosmic ray muon detector data flows. Good thing.

— April 23 PM: The crew relaxes with a movie and the bar is open. Everyone settles into the routine. Tomorrow is Easter. I will have to think about how to worship. I suspect I’ll be all alone about it.

— Bob Peterson

 

Related information:

You can follow the journey at:
http://expedition.awi.de

You can e-mail Bob questions at [email protected] Please send only text, no images.

Glossary

*Galley: A ship’s kitchen.

*Bridge: The elevated, enclosed platform on a ship from which the captain
and officers direct operations.

*Springs: Dock lines

*Breakwater: A barrier built out into a body of water to protect a coast or
harbor from the force of waves.

*Swell: A slow, regular movement of the sea in rolling
waves that do not break.

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Last week was yet another exciting moment for those of us who are researching the nature of dark matter. The long-awaited XENON(100) results were released. XENON, is the biggest rival to my own experiment, the Cryogenic Dark Matter Search, or CDMS.  In the world-wide race to discover dark matter, XENON and CDMS have been leading the pack over the past few years. These two experiments have been taking turns nudging ahead of each other, only to have the other pull ahead within about a year’s time.  This time around, XENON has made a fairly big leap ahead. While the XENON collaboration did not report a discovery, their data does provide significant new constraints on the many theories that aim to explain dark matter.  Their new result has lowered the possibility for dark matter interactions by a factor of ~4 over previous world limits.

I’m certain two of the big questions many now have for CDMS, are: What are our plans for the future and will we be taking the next jump that puts us in the lead? Though we’ve had a setback recently, I’m optimistic about CDMS.  We are in the process of starting a new phase of the experiment named SuperCDMS.  For SuperCDMS, we will implement a new detector design which will significantly increase our sensitivity to WIMPs. Last month, we were in the middle of testing these detectors when a fire broke out in the mine where the experiment resides. We are now waiting while the mine infrastructure is repaired. Once that is completed, we will begin our first physics run with the new detectors, which may be as soon as this summer. In the meantime, we are planning a much bigger version of the experiment at a much deeper underground site, SNOLAB in Canada. Both of these endeavors have planned sensitivities that exceed the current XENON limits.  

In the meantime, of course, the XENON collaboration will be continuing to gather more data and working on their next-generation experiment. However, based on their reported results, it is clear that they cannot simply improve their sensitivity with more of the same data. To push their sensitivity further, they must reduce intrinsic radioactive contaminants in their detector. Though they claim to have started a new run with higher purity levels, it’s unclear how long they can sustain the current conditions of the detector.  

So the worldwide race has tipped toward XENON for the time being, but meanwhile, the future of CDMS is bright. We don’t yet know what nature has to reveal or what the future will bring. This makes the world of dark matter research fascinating. No matter what happens, we all look forward to learning what the final outcome will be. For me, these are great reasons to push forward in the race to understand dark matter.

— Lauren Hsu

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DES First Light Countdown, seven months to go

At the time of my first post in the countdown to first light series, some people suggested that I write more on what I really do and what it is like to be a postdoc in the Dark Energy Survey, DES. And as much as I feel hesitant to turn the spotlight to myself, I would hate to let my very first readers down. So read along and you will learn, from a very particular perspective, how much progress we have made in the last two months.

DECam focal plane at Fermilab almost full of CCDs. Credit: Marcelle Soares-Santos

 Being a postdoc is like being a photon. You have a wave function and, while your career momentum may be well determined, your location in the multiverse of projects, working groups, meetings and responsibilities is very uncertain.

 During the Dark Energy Camera, DECam, test phase on the telescope simulator my wave function nearly collapsed around the Fermilab Silicon Facility, or SiDet. I was sitting right next to the camera, testing the ever evolving data acquisition system and the new components (shutter, filter changer, hexapod…) as they came online. This phase was completed in February and since then my wave-like behavior is more evident again. We have changed gears towards filling the focal plane with our brand new CCDs and preparing the camera for shipment to the Blanco telescope at Cerro Tololo Inter-American Observatory, or CTIO, in Chile. This week I am in Chile, attending the DECam integration meeting. It is my first time at the observatory and not only I am having a great time, but I am also learning a lot!      

Cerro Tololo Inter-American Observatory in Chile. Credit: NOAO

But being a photon also means that your rest mass is zero and your wave length is inversely proportional to the energy you dedicate to each particular task. Supervisors and project managers seem to know this very well and deliberately loosen or tighten their grip as they see fit. But it actually depends on the time scale of each project. The fact is that from time to time you feel the stress decrease in one area and your wave function automatically stretches to other activities.

DES simulated image. Credit: DES collaboration

I am also working on the cluster finders comparison project, which will help DES identify, with high efficiency, a sample of more than 100,000 galaxy clusters, the largest gravitationally bound objects in the universe. This area is where most of my science interest lies. I developed

a galaxy cluster finder and tested it on DES simulations, computed the selection functions to be applied to our data and studied the systematics. That meant time in front of a computer terminal, programming instead of testing camera components. I find programming a lot more fun and I like the flexibility to work from virtually anywhere. My office (well, it is a cube really) is the natural choice, but I do a lot of this work at home too (yes, work-life balance is that concept from the seventies that I haven’t internalized yet).

Last week we finished the installation of the software framework for the cluster finders comparison project — we have a handful of cluster finding algorithms in our collaboration.  This fall we will conduct a comprehensive test of our pipeline, through what is called the Blind Cosmology Challenge. The idea is to verify that we can recover the right answer in a simulated data set. This would prove our ability to measure the dark energy parameters DES wants to study. A great overview of this challenging project was presented by one of our collaborators in a talk at the KITP Conference last month.

So here is where we stand, at the seven-month mark. Integration and commissioning phases are imminent. And we are working hard to get ready on several fronts simultaneously. This requires a very broad wave function!

— Marcelle Soares-Santos

 

 

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A replica ring of the top-end of the Blanco telescope built at Fermilab to test assembly and operation of the dark energy camera before shipment to Chile. Credit: Fermilab/Cindy Arnold

This article ran in DOE Pulse April 4.

Building and installing one of the world’s largest digital cameras to solve the mystery of dark energy requires the collaboration of scientists and industry from across the globe. The Dark Energy Survey’s combination of survey area and depth will far surpass the scope of previous projects and provide researchers for the first time with four search techniques in one powerful instrument. More than 120 scientists are collaborating to determine the true nature of dark energy, the mysterious force that accelerates the expansion of the universe. Taking images of galaxies from the time the universe was only a few billion years old, the DES will trace the history of the expanding universe roughly three-quarters of the way back to the time of the Big Bang.

But first researchers needed to build the 570-megapixel camera at DOE’s Fermi National Accelerator Laboratory and make sure it works. Nearly all of the camera’s parts made their way to Fermilab for assembly and testing during the last 12 months. The components were assembled and operated on a full-size replica of the front end of the 4-meter Blanco telescope in Chile, built by Fermilab and Argonne National Laboratory.  Testing finished successfully in February. During the next few months, physicists will be putting the finishing touches on pieces of the camera and shipping them to the Cerro Tololo Inter-American Observatory in Chile where they will receive another round of tests before installation.

The high-tech supply chain tapped the expertise at four DOE Office of Science national laboratories and more than two dozen institutions and universities in the United States and abroad.  More than 120 companies in the United States contributed know-how and parts. Fermilab took the lead in the assembly and testing of the camera and building a cryogenics system several times larger than those used in previous ground-based sky surveys, while Berkeley and Argonne national laboratories played key roles in the camera development.

Berkeley Lab developed the Charge Coupled Devices used in the camera and did some of the processing of the silicon for the CCDs before sending the pieces to Fermilab for packaging of CCD chips. The unique design of these CCDs will give the camera unprecedented sensitivity for red and near-infrared wavelengths, allowing it to record more light for a given exposure time. The camera contains 62 CCDs for observing with 8 million pixels each, plus 12 CCDs with 4 million pixels each for guiding and focusing.

Argonne National Laboratory helped construct the calibration camera to conduct a mini-sky survey last year from a telescope adjacent to the Blanco telescope. This scaled-down version of the dark energy camera allowed for testing of the experiment hardware, software and observing strategies as well as created a baseline of celestial objects for Dark Energy Survey. Argonne also constructed several smaller components for the full-size camera and some large mechanical systems, including the heavy apparatus that installs and removes a 1-ton mirror from the front of the camera.

SLAC National Accelerator Laboratory took the lead in constructing a separate, small telescope with an infrared camera that will sit on a mountain near the Blanco telescope in a separate enclosure. This telescope will monitor cloud coverage so that the Dark Energy Camera can adapt its survey modes to various atmospheric conditions.

The DES collaboration expects to take its first astronomical images with the installed Dark Energy Camera before the end of 2011.

— Tona Kunz

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Lots of interesting particle physics news recently on the Cosmic Frontier front.

Science News reports that the National Research Council’s March 7 report for science in the coming decade recommends completion of the Large Synoptic Space Telescope.

…which will not only probe the nature of dark matter and dark energy but aid in tracking near-Earth asteroids.

LSST  is a huge public and private partnership, which includes many of the national labs, among them Fermilab, which hopes to build on its computing experience with the Sloan Digital Sky Survey to help manage the unprecedented flow of data expected from LSST. The February issue of symmetry magazine outlines the partnership needs the experiment will require.

…the LSST camera will produce 3.2-billion-pixel images and generate, on an average viewing night, about 15 terabytes of raw data, or 25,000 CDs worth. To display one of the LSST full-sky images on a television would require not just a high-definition screen, but 1500 of them.

While LSST is not expected to take data for quite sometime, its predecessor the Dark Energy Survey should start its first sky survey in October. The blog dark matter, dark energy, dark gravity explains how DES will be the first experiment to use four different methods at once to search for dark energy. Medill news services uses a great video to show physicists at Fermilab wrapping up tests on camera components before shipping the final parts to Chile for assembly on the 4-meter Blanco telescope. Sadly, the New York Times reports that the driving force behind making the telescope a bastion of U.S. science in Chile, Victor Blanco, passed away. 

Unlike DES and LSST, the holometer experiment aims not to record the sky as we see it but as Fermilab theorist Craig Hogan thinks it really is: a giant hologram.  The Little India newspaper explains Hogan’s theory and how it relates to black hole science.

Scientists have known for long time that information plays a key role in the creation of a system. Our computers and robots are just metals and wires if no information is exchanged in the form of bits. Our brain is inanimate if no information is carried by the neurons. Our genes are futile if no information is available from DNA that instructs how to function. In everything we know information is the key.

Similarly the entire information about our universe must be encoded elsewhere. Like a hologram on our credit cards, which contains the information in a thin film, and can generate 3D objects when viewed in proper light, the reality we tempt to believe is actually just one way of viewing information printed on a distant cosmic film. What we see and experience as reality are the shadows of the truth.

–Tona Kunz

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