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Posts Tagged ‘QuarkNet’

Editor’s note: Bob Peterson ends his month-long journey in the Atlantic Ocean with two cosmic ray muon detectors, collecting data for science and education programs that use similar detectors. Look for future Quantum Diaries posts explaining how the data gets used and how the two detectors get used on dry land. Hopefully, you’ll also get to see some of the photos from the journey, which Peterson couldn’t send from the ship.

Follow the 10-part journey 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, Cosmic ray detector weathers sea mount survey and storms.

18 May 2011
R/V Polarstern
Latitude: 51-30.8 N
Longitude: 2-17.3 E
English Channel
Ship course 40° T
Ship velocity 10.3kt

18 May: Bob’s Last Polarstern Blog

France just showed up off the starboard rail. We’ve been in the soup since entering the English Channel, fog so thick you can’t see the toes in front of your feet. All the surrounding ships disappeared and the onboard birds are staying close. The only means of verifying location is the radar and the navigator’s chart. The ships had to trust the captains and the captains had to trust their charts. Scary for the ships; they have no eyes. But, there is France. We will be off Calais in an hour and half. Hope the visibility holds.

This will be the last blog installment as the radio officer shuts down the mail server tomorrow at 1200 ship time; not 1201.

There is much activity onboard as data-taking has stopped and instruments are finding their way to packing cases. The experiments I’ve talked about in these posts are finished: no more LIDAR, no more microwave cloud measurements, no more deep-echo sounding,. But the cosmic ray muon detector keeps clicking over. I’m going to take data all night; shut down and pack up tomorrow morning.

Arrival at Bremerhaven will occur at 0600 Friday morning assuming the pilot is on time (remember Las Palmas?). Quick good byes as the German scientists want to get home. The crew waits for their “pay-off” as in the old days before they depart the ship. Then the Polarstern goes to dry dock for “haul-out” and maintenance. It will have three weeks out of the water and then departure for the Arctic. Much of the same crew will sail again including Max and Klaus in the weather office.

It’s been a truly amazing trip for me. I recommend a new book, “Atlantic” by Winchester. It captures some of the scale of this body of water. The book covers history, oceanography, geology, sea battles, survival stories and sea life. I started reading it in Cape Town; finished it off of Gibraltar It’s a
worthwhile read.

Ship’s bell just rang for dinner. Thanks to all for reading and sending me mail. It was nice to feel the connection from friends, family and colleagues when so far away.

— Bob Peterson

Glossary

*Starboard: The right side of the ship.

*Soup: Fog

*Pay-off: After a ship’s arrival in port, the captain would meet the crew (who had spent the night on the town) the next morning to pay the crew in cash or gold.

*Haul-out: In the old days, a ship would be pulled out of the water using a railway and cradle; now ships use dry-docks, which pump the water out of the basin containing the ship.

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Balloon launch busted by boat

Friday, June 3rd, 2011

Editor’s note: Bob’s most excellent particle detector adventure, part 9.

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 previous posts:  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, Cosmic ray detector weathers sea mount survey and storms.

17 May 2011
R/V Polarstern
Latitude: 48-29.8 N
Longitude: 5-50.9 W
Bay of Biscay
Ship course 033° T
Ship velocity 11.2 knots

17 May:
That was quite a storm starting the early morn on Saturday, and it didn’t abate ’til Monday morn. The Polarstern was caught between a high-pressure system to the north and a low-pressure system south of us. The two conspired to “blow like stink” straight on the nose into the direction we needed to go. So, pound away we did, making progress at about 3-5 knots. You can walk that fast. (Well, not on the Atlantic Ocean in the midst of a storm, but you get the idea.)

At the height of the storm, it blew at 45 knots and Klaus estimated wave heights at 20 to25 feet tall. (As a weather technician, that’s what Klaus does; estimate the wave conditions. He also launches the weather balloons. More on that later.) My bunk runs fore to aft, which made the ship motion easier to bear; athwart ship and I would have gotten rolled out of my bunk. Still, I did not sleep well for two nights. But, Max and Klaus said that was nothing. They shared stories and pictures of hurricane force winds in the southern ice.

By Monday afternoon the storm had blown itself out and the waves had gone away and wind had gone away and the entire ship’s company had a nice pleasant BBQ dinner: well- deserved with roast pig and all the trimmings.

The cosmic ray muon detector (CRMD) ignored the storm and keep on taking data. An important data set that we hope to couple our data to is the upper-level balloon soundings. This requires a once-a-day balloon launch and faithful to his charge, Klaus proceeded in the midst of the storm. He has recruited a small group of graduate students to assist. (Well, I recruited, and he pretended to resist assistance Tom-Sawyer style.)

On the Saturday when Julia launched the balloon, it got caught in the slip stream behind the ship and forced down and toward the large A- frame mounted on the transom. The ship stern pitched up; the balloon went down and zoomed under the A- frame. Klaus said, “Hmmmm, never did that before!” Unfortunately, the radiosonde dipped in the water and the entire signal was lost. A busted flight.

Cosmic ray muon detector. Credit: Fermilab

The ship board pulse has quickened as we are a couple hours from entering the English Channel. This is a controlled water way. So, ships are under guidance and obliged to stay on the right-hand side of the road. And just as the second mate predicted, many ships are now on the horizon converging to take their turns through the Channel. I count eight within view, and they are BIG ships. Home is not far. We will arrive in Bremerhaven at 0600 Friday morn.

Michael Walter will meet me and proceed with one cosmic ray muon detector to DESY, a physics laboratory in Germany, for use by education groups in the area. Tomorrow, I will disassemble the detector marking the end of the data session. My cosmic ray muon detector will end up at CERN, the European high-energy physics laboratory in Switzerland.

Glossary

*Fore: Forward

*Aft: The opposite of forward. Tricky, eh?

*Athwart ship: If fore and aft runs the length of the ship, then athwart ship is across the width of the ship.

*Transom: The flat surface forming the stern of a vessel.

*Pitch: A swaying or oscillation of a ship, aircraft or vehicle around a horizontal axis perpendicular to the direction of motion.

*Stern: The rearmost part of a ship or boat

*Radiosonde: An instrument carried by balloon or other means to various levels of the atmosphere and transmitting measurements by radio.

–Bob Peterson

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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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A cosmic ray shower.

Editor’s note: Bob’s most excellent particle detector adventure, part 7.

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.

11 May 2011
R/V Polarstern
Latitude: 30-56.1 N
Longitude: 14-27.0 W
off the Moroccan coast
Ship course 017° T
Ship velocity 10.8 knots

10 May:
Dawn; the forecast called for a sunny day? What’s that cloud bank out my cabin window? Oh, wait, that’s land! Ah, the Canary Islands right on schedule just as the navigator predicted, and we approach Las Palmas harbor from the south.

The Polarstern receives the pilot at 0945 (he’s late), and the ship proceeds cautiously into the slip. Forty-five minutes later, dock lines are thrown and we are winched tight to the quay and the gangway lowered.

We are here to receive new scientists from Alfred Wegner Institute, or AWI, coming onboard for special training in echo acoustics and bottom profiling. And it gives some of us a chance to feel land. Shore leave is two hours; be back by 1400 or the captain will not be happy. So, I escape. Sure enough the land is moving in a wave-like motion. I must have sea-legs.

Underway again at 1745. The pilot was late again. By 1830, the Canary Islands are falling behind and slipping into the sunset haze.

How IceCube works. Credit: IceCube collaboration

11 May:
Daily, the Polarstern weather technician, Klaus, launches a weather balloon for upper-atmosphere soundings. Michael Walter, my contact from DESY/IceCube, needs these data. I’m intrigued, so Klaus gladly offers to train me to ready and launch the balloons. This will be fun.

All over the world, weather stations and ships launch these balloons simultaneously, and they need to be at 10 kilometers, or 6 miles, altitude by 1200 Coordinated Universal Time, or UTC. So, Klaus prepares and launches the balloon one hour before because it takes that long to reach 33,000 feet. The balloons are filled with helium to about five feet diameter and carry a small data collection transponder called a radiosonde.

Launchings on land are straight forward; the technician steps out of the filing garage and let’s go. On ship, it’s anything but simple. The deck is pitching and rolling, the forward speed sweeps the deck with maybe 35 knots of wind, and the tall crow’s nest in the center of the ship is definitely in the way. There will be no end of grief from the crew if I hang the balloon there. So, Klaus coaches (and laughs) as I learn to manage the recalcitrant, reluctant object, but I’ve now mastered the preparation and launch. Launchings are analogous to a young boy throwing a rock off a cliff; except, it defies gravity. What fun to watch it sail away. I wonder how long I can still see it before it disappears into the haze.

The data returns to the ship in one-second intervals, showing the profiles of atmosphere parameters. The soundings return data on altitude, pressure, temperature, humidity and wind speed and these data might couple to the QuarkNet cosmic ray muon detector (CRMD) data. Michael Walter will use this to correlate to the cosmic ray flux, or flow rate of cosmic ray remnant particles passing through various areas of the sky. I hope that QuarkNet students can do the same. I, too, will return home with the large data sets to compare to the onboard QuarkNet detector.

Glossary:

*Quay: Pronounced “key”. A concrete, stone or metal platform lying
alongside or projecting into water for loading and unloading ships. Similar to a
pier.

*Pilot: a master mariner hired by the captain to guide a big ship into confined harbors. They have special local knowledge and training. Still the ship’s captain is ultimately responsible. A pilot job is nice if you can get it, because all have to wait for the pilot. They are notoriously late.

*Winch: A hauling or lifting device consisting of a rope, cable or chain winding around a horizontal, rotating drum, turned by a crank or by a motor or other power source.

*AWI: Alfred Wegner Institute – Research facility that owns and manages the R/V Polarstern.

*UTC: Coordinated Universal Time

*Radiosonde: An instrument carried by balloon or other means to various levels of the atmosphere and transmitting measurements by radio.

*Crow’s nest: A shelter or platform fixed near the top of the mast of a vessel as a place for instruments or lookout.

–Bob Peterson

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A teaching moment on the sea

Wednesday, May 18th, 2011

Cosmic rays collide with the Earth's atmosphere and rain down secondary particles.

Editor’s note: Bob’s most excellent particle detector adventure, part 6.

 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

8 May 2011
R/V Polarstern
Latitude: 23-13.3 N
Longitude: 20-29.1 W
off the coast of Mauritania
Ship course 21° T
Ship velocity 6.1 knots

8 May:
The ship, scientists, officers and crew have settled into routines. All have learned where things are located, the best time to get tasks done and whom to ask for help. Unfortunately, no one can help the cosmic ray muon detector.

The photo multiplier tube connected to channel four finally gave up the ghost, and I had to put it to sleep. I unplugged it.
The severed wires refused to stay connected even with jury-rigged foam, tape and flotsam. Channel four would record for a short while then would drop off line and the data flow would stop. So, data-taking will continue with three channels and three-fold coincidence. That should hold through the end of the voyage.

Part of the ship’s routine includes evening science talks given by researchers on board. I was the first and surprised everyone. Instead of talking about cosmic-ray science, I spoke about QuarkNet and how it supports authentic learning by helping students study cosmic rays in the classroom. After all, I am a teacher.

One example of how a cosmic ray detector can transfer data to a computer and upload to the e-Lab. Credit: Fermilab

The room full of scientists resonated with the QuarkNet approach, which provides support for particle physicists at universities and national laboratories to form long-term collaborations with local high school teachers. High school students analysis real-time cosmic ray muon data and share their results online with students around the globe in e-Labs, just like today’s international science collaborations.

My onboard companions understood immediately the value of giving teachers and students genuine research experiences Students build their detectors from scratch just as physicists do. You won’t find the step-by-step directions you find on furniture or toys such as “part A goes in slot A.” Students learn problem-solving skills they’ll use in everyday life as they figure out how to put the detector together, finding the best location in the high school for it and forging partnerships with groups at school. One group had to work with its IT department to figure out how to get approval to put a hole in a wall so that they could get their antenna on the south side of the building where the GPS satellite signal was best for connecting to the data acquisition system. It takes ingenuity to make it work. But that’s what makes the program so great.

It was an easy talk to give as I have beena happy warrior for QuarkNet since joining the program In 2004. From colleagues Tom Jordan and Marge Bardeen, I quickly learned the worth of letting QuarkNet users “ask their own questions” and design their research approaches. It is nice to offer such a rich project as cosmic-ray research because there remain many open-ended questions for teachers and students to chew on.

Teachers in Idaho transport a cosmic ray detector to various altitudes on a mountain to compare the number of particle interactions. Courtesy of Bob Peterson

Part of my purpose onboard the R/V Polarstern is to gather a unique data set to add to the Cosmic Ray e-Lab where students can analyze data. This data will join data contributed from IceCube at the South Pole and other data from the Polarstern on previous trips.  The e-Lab offers friendly data-analysis tools, guides teachers and students to develop quality research questions and encourages them to support conclusions with evidence. We modeled the approach on the professional life of scientists, especially particle physicists. Students upload data from their classroom cosmic ray muon detector. The e-Lab provides analysis tools and lowers the threshold to understanding the physics embedded in the data. The hardware and e-Lab couple tightly together as a complete science education experience.

Right now, over 200 cosmic ray muon detectors s have been distributed in the United States; another 100 international. You can find QuarkNet participants in: Brazil, Canada, China, France, The Republic of Georgia, Great Britain, India, Mexico, Japan, Poland, Puerto Rico, Russia, Singapore and Thailand.

All this data offer students plenty of research options. For example, during the last solar maximum QuarkNet had no cosmic ray detectors in classrooms. With detectors now in place, users are ready to examine the effect of solar storms on cosmic-ray flux. Many other questions are possible, such as looking for cosmic-ray shower coincidence or how well a detector is performing.

The Polarstern seems to be ahead of schedule for we have slowed down and changed course headed for Las Palmas in the Canary Islands. We arrive on 10 May for a quick stay to pick up additional science crew; no shore leave allowed. Too bad.

The sea state has continued “on the nose”. With the northeast trade winds of 15-18 knots and a forward speed of 12 knots, that makes it 30 knots over the deck. That’s hard to stand with the ship’s motion. The Atlantic remains immense in my view. 19 days at sea and I saw my first jet contrail today. I have yet to see another ship. They promise there will be plenty as we approach the English Channel.

Glossary:
*Flotsam: the wreckage of a ship or its cargo found floating on the sea.

*Coincidences: The cosmic ray muon detector looks for what we call coincidences, two signals, one from each photo multiplier tubes, 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

*Jet contrail: The condensation trail left behind jet aircraft.

Related information:

A blog written by Wisconsin university students on the first data taking boat trip.

Read how they explained their trip while visiting Washington DC.

—  Bob Peterson

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Editor’s note: Bob’s most excellent particle detector adventure, part 5.

 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

4 May 2011
R/V Polarstern
Latitude: 9-47.1 N
Longitude: 19-46.2 W
off the coast of Guinea
Ship course 320 ° T
Ship velocity 10.1 knots

4 May 2011:
Two days ago, the R/V Polarstern stopped mid-ocean at latitude: 00-00.053S, longitude: 11-39.259W.

By my reckoning, that’s 318 feet south of that east-west line “painted” in the water. Guilty parties were forced into very little rubber rafts and pointed in obscure directions and told to “cross the line”. Only one actually knew which way to go. After circular paddling, which amounted to three times the distance required to cross the line, those guilty of being equator-crossing newbies were initiated as shellbacks .

And what an initiation it was.

Water color painting Lord Neptune by Shakti Prasad Srichandan.

Neptune, lord of the sea, and his court rose up out of the Atlantic for the ritual baptism of those who had violated his domain. A trial was held and renaming of the pollywogs was required. Much fun and antics was had by the entire crew as they put on a real show of cruel and dastardly deeds. I could almost hear them cackling like the pirates of days past: “Arrrghhh! Avast ye maties!”

Bathing in stinky slop ensued, ceremonial memorizing of creeds was demanded and kissing of the feet of Neptune’s wives was enjoyed. Men in drag wearing clown shoes slathered in mustard and horseradish sauce stood in for Neptune’s wives. Lovely. I was also assisted by large, burly men with tattoos into a baptismal font made from a large fish basket. Four times I went in it; I must have been extra sinful. Each dunking got nastier as more people were “baptized”.

Finally they branded our stomachs with Neptune’s trident. This was a bit scary because they covered our faces with hoods execution-style and we could hear the metal trident heating in a charcoal grill and sizzling as it pressed onto flesh. Thankfully, when it came to my turn I found out the sizzle was the trident branding a raw piece of meat that then got slapped onto my stomach.  The crew got a great laugh out of our initiation.

We earned certificates for our ceremonial passage and a feast at sunset. Neptune felt the ceremony was befitting and left without taking the ship with him. So I am now the shellback known as Cosmic-Ray Rider, and I have pictures and a certificate to prove it.

Those will have to do because I skipped one of the most permanent parts of the ceremony. While I appreciate all the suggestions of earring types from friends and family, I decided to forego that little ritual. It’s the burly men that punch the hole, and they’re none too delicate.

So, the cosmic ray muon detector gave me my shellback name, but it’s also been my source of grief. Sometimes delicate instruments refuse to cooperate. For me, the trouble has been channel four and a scintillator counter that drops off line. Of course, it’s the one on the bottom of the stack, and it chooses to act up in the middle of the night. Several times in the morning I find it asleep, and that no data was taken during the night. Suspecting a light leak, I rewrapped it twice. Nope; that’s not it. Then I discover a flakey wire into the photo multiplier tube. There must be a short inside that photo multiplier tube. To compensate, I have lowered the coincidence to 3-fold from four so that a particle signal recorded in the three working sections of the detector will count as cosmic ray remnant event. Now, I will at least get some data. A replacement wire is some 8,000 miles away at Fermilab and the parts you can find along our route are pretty wet wheeling, as they say.

Bob Peterson holds part of the electronics for the cosmic ray muon detector. Credit: Tona Kunz

After many days in the southeast trade winds, we pushed through the doldrums, an area of still air near the equator that seems to rise rather than blow, and into the northeast trade winds. Other than the stop for the equator crossing, our course and speed have been relentless: 320 ° T, 11 knots; however, the following winds and swell have now turned on the nose and have become quite lumpy. Max, the weather guesser, promises it will get worse. In several days we make a turn to the north and a planned stop at the Canary Islands to pick more scientists.

Glossary:
*Pollywog: Some no good, inexperienced mariner who has never crossed the equator.

*Shellback: The opposite of a pollywog.

*Coincidences: The cosmic ray muon detector looks for what we call coincidences, two signals, one from each photo multiplier tubes, 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.

— Bob Peterson

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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 rpeterson.p@awi-polarstern.de. 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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Bob Peterson has agreed to forfeit a month of his time and his non-sea-loving stomach, for a briefer period, in the name of science.

Bob Peterson

This Fermilab employee and QuarkNet instructor will shepherd a cosmic ray muon detector through rolling ocean waves around the edge of Africa to gather data to help the world’s largest frozen particle detector, the IceCube neutrino observatory at the South Pole. The detector is the same type as those built and used by high school students in cosmic ray study projects, including QuarkNet program, which allows students throughout the world to collect and share particle physics data. QuarkNet gives students a chance to interact with physicists and get a taste of what it would be like to work on a global experiment such as IceCube.

IceCube serves as a neutrino telescope peering at neutrino particles that cascade out of collisions of high-energy cosmic rays with the Earth’s atmosphere. The trick is that IceCube only wants to look at these cosmic neutrino remnants coming from a certain direction, from the opposite hemisphere and through the Earth, not those falling directly overhead of the detector.

The data Peterson collects will help IceTop, a smaller detector set a top IceCube, to give the most precise data to the IceCube collaboration so that it knows it is focusing on the right particles. His data will be combined with data collected on a similar trip last year in Antarctica by a group of Wisconsin college physics students. This combined data will tell researchers the varying intensity levels of cosmic ray remnants as you travel from the equator to the poles. This will help the IceTop collaboration calibrate its detector to compare data to IceCube and help IceCube reject background particles from downward cosmic ray remnants that can obscure the detectors’ views of neutrinos moving upward through the Earth.

Sketch of the IceCube detector. Each cross on the surface represents two IceTop tanks. Credit: IceTop Collaboration

Studying neutrinos in one of the coldest places on Earth will help scientists get a better picture of where high-energy neutrinos originate and how they contribute to the universe’s most violent events, exploding stars called supernovaes. These explosions spit out the heavy elements necessary for the creation of life on Earth. Without these neutrino-fed explosions the universe would look very, very different.

And so Peterson, an avid sailor, who gets sea sick for the first few days of every journey, packed up his gear and headed out to learn about the universe and its most distant, violent objects by riding on a boat.

He is blogging his adventures in science and seafaring here at Quantum Diaries. A glossary of sailing terms will appear at the bottom of each post to aid readers.

23 Apr 2011, R/V Polarstern
Lat: 24-50.5S
Long: 9-42.7E
somewhere off the Namibia coast
Heading: 320degT
Speed: 12 knots

Bob’s Blog begins wherein Bob is on a voyage aboard a German research vessel to the Southern Hemisphere and discovering that using the Internet aboard a ship isn’t that simple.

–April 18: I had a really nice blog written yesterday, but the mail server timed out, and poof. No more. Then I found out from others that, oh yes, that happened to them, too. Well, I won’t do that again.

–April 19 AM: I arrived in Cape Town, South Africa, late Monday night after a 26-hour flight. The trip took me through Dulles Airport and then through Dakar across the Atlantic. I recommend South Africa Airlines; they are good with comfort and food. But still, there I was standing in CPT wondering who was picking me up. After a few nervous minutes, the driver for the ships’ agent, Randal, found me contemplating my next move. Ah, now I’m in good hands as we visit the immigration office where there is much stamping of documents.

I was somewhat foggy after such a long trip. Finding my ship proved not so simple because another ship on the quay was bunkering at the time of my arrival. But I finally made my way down the narrow quay to the gangway and the R/V Polarstern. My question, “Permission to board?” was met with a blank stare, and by then Randal was long gone so retreating was not an option. Just when I thought I would have to take my chances on the neighboring rust bucket (the one that was bunkering), the 2nd Mate, Philipp Gumtow, appeared welcoming me aboard; he took charge of the situation. Soon, I was surveying my cabin and eyeing a nice bunk.

–April 19: My wake-up alarm came from a departing tanker from the next quay over (not from the rust bucket). The traditional departure signal is one long blast, and they care not who is sleeping. Fine, I’m awake. Time for breakfast. Where’s the galley? I find it, and there I meet Philipp again. He tells me, “No, this table is reserved for crew; you sit over there at the science table”.  Ah, the world on the Polarstern is segregated: crew, officers, scientists. I think I fall somewhere in between. A ship is like a summer camp. It is all about procedures and everyone must abide or chaos ensues. The trick is find a friendly party that will explain those procedures before I step over the unseen boundaries. Tina was just that person. She is a biology grad student studying the effect of ocean warming on pelagic fish.

Then I try a quick tour of the ship, but within three turns of a corner I’m completely turned around. The Polarstern has seven decks connected by a central stairs and many doors with inscrutable labels all written in German. This is my handicap. Still, my exploration starts from my cabin to the galley and back and expands from there.

–April 19 AM: The Cape Town harbor sits at the bottom of the continent where 5,000-foot mountains loom. It shelters many ships bound for ports to the West, but not the East because of the threat of pirates. Cape Town traffic has increased as cargo is off loaded to rail and truck to avoid the east side of Africa, and likewise cargo is received for the journey west.

There are big ships here: tankers, container ships, general cargo, oil rigs, crew boats for the rigs and rust buckets. There are some tied to a remote pier called the graveyard. They will soon become target practice or cut up for scrap. One ship stands out; so I go ashore for pictures. With its many derricks and lots of deck plumbing, I want to get a closer look at the Peace in Africa. No kidding, that’s the name. Immediately a shore officer wants to confiscate my camera. “No way,” I say. Then I notice the owner: DeBeers. This ship mines the ocean bottom for diamonds; think Howard Hughes and magnesium nodules. Peace in Africa my foot. I beat a hasty retreat back to the safety of the Polarstern.

QuarkNet detector taken on ship. Credit: Fermilab

— April 19 AM: All the while, I’m wondering: Where is my cosmic ray muon detector? I ask Sonja who is the agent handling all the Polarstern logistics, whether she has seen it. She says that she will check and let me know.

— April 19 PM: Whoops, my first surprise. The money onboard is the euro……. I knew that, but they require cash. Now I’m in trouble; my credit card will do me no good. I must come up with cash; Sonja offers help and a driver to a downtown bank. But, this quickly goes bust as the banks refuse to exchange dollars for euros especially for someone on a ship. You must have an account and a permanent address. Hmmmm, I think they’ve been burned before? What to do?

–April 19 PM: Sonja has found my box. It’s in Cape Town. Closer, but still not onboard.

–April 19 PM: All ships use an agent for logistics and paper work. The Polarstern uses Meihizen International. They are skilled at problem solving, including my cash shortage problem, and they gladly offer help. First, I will retrieve South African rands from an ATM; then the agent will go to his bank for euros because he has permanent-resident status. My money goes from credit card dollars to rands to euros and I can feel a slice out of my funds at every step.

Still, the snafu gave me a tour of Cape Town and a genial meeting with the president of the agent company. He’s a sailor; I’m a sailor. We get along famously; I’m invited back for a cruise on his yacht. Nice yacht.

–April 19, much later PM: The day is getting late, and I learn we will depart at exactly 2000 (8 p.m.) on Wednesday with or without my cosmic ray muon detector. Sonja says the box is now at the agent’s office. It’s closer and will be delivered late afternoon. Sure enough, I see it come out of the delivery truck and get hoisted via the ship’s crane (I think: Please don’t drop it boys) to the receiving deck.

But, still I can’t have it. I am told that the cargo mate must verify the box on his manifest list. The officer will release it tomorrow morning.

GLOSSARY:

*quay: pronounced “key”.  A concrete, stone, or metal platform lying
alongside or projecting into water for loading and unloading ships. Similar to a
pier.

*bunkering: fueling a ship.

*galley: kitchen

*manifest: A document giving comprehensive details of a ship, its cargo
and other contents, passengers,and crew for the use of customs officers.

— Bob Peterson

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