2016 McGill South Pole Blog

Background: A blog describing our team's adventures installing and commission the new South Pole Telescope third generation camera. This experiment is designed to measure the CMB B-mode polarization, exposing the signatures of gravitational lensing and, perhaps, evidence of gravitational waves from the early universe. The camera, like its predecessor, used readout electronics developed and built by our Lab at McGill. Joshua Montgomery and Matt Dobbs are representing McGill. We’re part of a much larger team that includes our partners from across the USA. Together, we’ll log more than 1100 days at the South Pole, bringing this project to fruition. 

November 13, 2016 - Christchurch, New Zealand

Completed leg two of travel (Montreal - Vancouver - Auckland - Christchurch - McMurdo - South Pole), landing in Auckland, New Zealand. The airport had a sombre mood and every TV was tuned to the news.

An earthquake about 40 times more powerful than the one that destroyed much of Christchurch 5 years ago had struck while we were in the air. (see https://www.google.ca/…/New-Zealand-earthquake-Massive-6-3-… for photos from the quake damage) Fortunately it was centered further from any big populations. The most outrageous thing was that it triggered a landslide which dammed a river. The dam held for most of the day, then burst about 4pm, sending a huge wave of water down. Fortunately only a few homes in its path and the authorities were able to predict this and pull rafters and kayaker from the river. Impressive preparation and response.

November 14, 2016 - Christchurch, New Zealand

I was out running in the beautiful park at the center of Christchurch when a call came through from Adam Anderson, a scientist from Chicago who had just arrived, “I’m over at the airport -- they can get us on tomorrow morning’s flight, if you can get here soon”. This is a day earlier than schedule, a spin off from the earthquake. Flights to “the ice” that were scheduled for Nov 14 were delayed until the 15th, allowing us to slip on today's flight tomorrow (you may have to read that twice for full comprehension).

I raced back to my hotel and jumped in an Uber to get back to the airport. Angus, the kiwi in charge of the center, took me into the extreme weather clothing room to sign out my gear and delivered an ultra-fast private version of  the "ice training" training we all get each time we go to antarctica.

So we’re off to Antarctica tomorrow if weather cooperates. A special thanks to the excellent welcome by the local Christchurch CADC staff, who keep everything working smoothly, even in the toughest of conditions.

November 15, 2016 - Flight to Antarctica

November 16, 2016 - McMurdo Station, Antarctica

Our team made it to McMurdo station, on an island off the coast of Antarctica, yesterday. We are one day earlier than expected. Tonight we're scheduled for the 5th and final leg of the Journey - a 4 hour flight on board a C130 hercules propellor plane to the South Pole. Fingers crossed for clear weather. While we are ahead of schedule by a day (unprecedented, as far as I know), our advance crew was delayed a full week and just arrived today. Our cargo seems to be scattered amongst several flights. With some luck (and encouraging visits to our friends in cargo), hopefully we'll be regrouped and ready to start work tomorrow.

We’re here install and commission the new South Pole Telescope third generation camera. It is designed to measure the CMB B-mode polarization, exposing the signatures of gravitational lensing and, perhaps, evidence of gravitational waves from the early universe. The camera, like its predecessor, used readout electronics developed and built by our Lab at McGill. Joshua Montgomery and Matt Dobbs are representing McGill. We’re part of a much larger team that includes our partners from across the USA. Together, we’ll log more than 1100 days at the South Pole, bringing this project to fruition.

Photo: Matt Dobbs in front of the C17 transport jet, on Williams airfield, Antarctica. here on the coast is fairly warm, about -5C, with tonnes of sunshine (all day and night). Right- a view of McMurdo station, a small town of about 1000 people, from Arrival Heights where Scott’s team, their boat frozen in the sea ice, searched the horizon for ships. The monument remembers a US serviceman who lost his life when his tractor broke through the sea ice in the 1950s, when they were establishing this station. McMurdo is the main service hub for the US operations in antarctica.

November 17, 2016 - The South Pole

Writing this from the C-130 ski-equipped Hercules prop-plane that is taking us to the South Pole. We didn’t get out last night, due to weather. This final leg of our journey is the most uncertain. The planes are operated by the New York national guard. In this environment, their tolerance for risk is really, really low - any fog or bad weather on the landing strip, and the flight gets cancelled.

Today, they have 3 LC-130 planes flying, and they have scheduled flights for 7 locations. Only three of these will happen. They start by prioritizing the destinations - if there’s a field station running low on fuel or food, that destination will get highest priority. Right now, we have pretty high priority for our flight to Pole, because much of the cargo that is needed for successful installation of our instrument this year is still in McMurdo. We have people at pole that will be idle if this gear doesn’t get there, jeopardizing our chances of success this season. This allowed us to have number 2 priority for today’s list of seven flights. With the priorities established, the air ops people integrate weather information from each location and make decisions throughout the day, while passengers and cargo stands by. Fortunately, weather was good this morning at Pole, so our flight was “activated”. They packed us in to a Delta transport vehicle, and began loading our cargo on the aircraft.

Earlier in the week, our advance crew had the reverse luck. They were prioritized lower. This meant that if weather was good everywhere on the continent, then the first few priorities would fly, and their flight would be cancelled - they were getting pretty stressed hanging out in McMurdo, stuck with only their emergency carry-on gear, waiting for almost a week to get out.

Being on a flight that is scheduled, but gets cancelled, is a bit of a grunt. You start by “bag dragging” the night before. This means that you have to show up at the air ops building at a specific time, dragging all your gear and baggage up, and fully decked out in the extreme weather gear that is mandatory for all flights. They weigh and palletize your baggage, and inspect/weigh you. You’re sent back to the dorms with your carry on bag, to await transport the next day. In the morning, you suit up again and drag yourself out to the air  ops building. They give you the once over (to ensure everyone is overheating in their extreme weather gear even though we’re still inside), then drive you about 45 minutes out to the airfield. You stand around and hope your flight is activated. With each plane that takes off, you know your chances are getting lower. If you’re lucky, your priority is high enough, and the weather cooperates, you’re called onto a plane before the 3rd one lifts off. If you’re not, you pack it back to base and, hopefully, repeat the next day.

Meanwhile at the South Pole, our advance crew turned off the SPTpol camera (the predecessor to the new SPT3g camera we’re installing) for the the last time today. I was part of the crew that installed the SPTpol camera in 2010. It brought polarization sensitivity to the South Pole Telescope and allowed us to make the first detection of gravitational lensing B-mode polarization in the CMB, a paper led by McGill postdoc Duncan Hansen. The SPTpol camera used a readout system built at McGill, like the new camera does. It’ll be sad to see that beast of a camera off.

Friday November 18, 2016 - The South Pole

Saturday November 19, 2016 - The South Pole

Photos: A dozer picks up the old SPTpol optics cryostat from a hole that has been made in the side of the dark sector lab. The ops folks are great at making things happen - notice the snow ramp they have built up to the wall-hole.

We made it to the south pole Nov 17, flying over antarctica through clear blue skies. (photo: Adam Anderson walking from the transport plane to the station). The rest of the SPT crew welcomed us and we got to work immediately removing the old SPTpol camera from the telescope cabin (photo). We were all feeling a little light-headed due to the altitude, having travelled from sea level to 3000m (10,000') to quickly.

November 21, 2016 - The South Pole

Photos: Kyle Story disassembles the superconducting detectors and quantum interference amplifiers from the old SPTpol camera, readying it for redeployment back to the USA. (right) Joshua Sobrin polishes the new SPT3g camera’s cryostat, to remove any residues that may jeopardize its vacuum. This cryostat will cool the SPT3g detectors to 280 mK (about - 273C). It’s cold outside here, but its really cold in that cryostat!

Monday November 22, 2016

Photos: there's usually an hour of so of downtime after dinner each night before the satellite comes up and we can start communicating with the north and looking up all those things that remind us how dependent we are on the internet. The climbing gym, hidden out in one of the shacks behind the station, or the music room, are favourites.

Thursday November 24, 2016 - The South Pole

(left) SPT team-member Dr. Amy Bender, from Argonne Labs (formerly a McGill Cosmo lab postdoc) with an SPT3g detector focal plane element. Ten such elements tile the camera's focal plane. Each element has about 1,600 detectors, making a single element as powerful as the previous SPTpol camera was.The white "lenslets" focus microwave light onto polarization sensitive antennas. The light received by the antennas are sorted into different frequency bands (or "colors"), and the power is absorbed in a bolometric detector. Behind the detectors sits the multiplexing electronics. All of this hardware is cooled to 270 mK in the SPT3g cryostat.

(right) Brad Benson (Fermilab) and John Carlstrom (Chicago) prepare an SPT3g lens. The lens is cooled to 4 kelvin.

Friday November 25, 2016 - The South Pole

Saturday November 26, 2016 - Thanksgiving at the Pole

The Antarctic Services Contract folks at the pole work 6 day weeks providing support (the fuelies, UTs, carps, sparkies, galley staff, etc.) [translation: the ones who fuel the planes/generators, utilities technicians who keep the power plant going, carpenters, electricians, restaurant staff…], but on American thanksgiving, they get saturday off. So, naturally, the whole station comes together to throw a big party.

It’s important to get dolled up for the party. Our South Pole Telescope crew definitely raised some eyebrows with our fine dress, scavenged from the SKUA (free stuff shack, named for the scavenger bird that is native to antarctica), and modified in the craft room by Berkeley grad student Jessica Avva.

Brad, Jessica, Erik, Joshua (Sweta is his wife, don’t worry), and Adam (yes, that’s a 1985 bottle of port, imported from Portugal to Cambridge to the USA to New Zealand to the South Pole - thanks for sharing Adam!).

Photos: The Galley, decked out for Thanksgiving and the evening’s menu, prepared by chef Big Country (yup, that’s what he's called).

After dinner, the SPT crew retired to the music room - where we had quite an eclectic mix of instruments and found that all ten of us could play (or fake) something.

Monday November 28, 2016 (posted Dec 4)

Photos: McGill designs and  builds the detector readout electronics for SPT3g - top left is a crate of boards, capable of reading out about 8000 detectors (that’s a lot by 2016 standards!). Top right and bottom are circuit boards housing the cold superconducting readout hardware - these boards are co-designed by Argonne National lab and McGill. At McGill, engineers Adam Gilbert, J-F Cliche, and Graeme Smecher (who won the South Pole half-marathon a few years ago) are part of the behind-the-science special sauce that make these systems work so well.

Thursday Dec 1, 2016 (posted Dec 4)

The remaining essential components for the SPT3g camera arrived after many cancelled flights on Monday, so we’ve started working long days to put the camera together and catch up on the time we’ve lost. The team is enthusiastic and everyone is enjoyed the go-go-go attitude.

(left) Kyle, that’s a really big torque wrench. (middle) It’s like Christmas here, as we wrap key areas of the camera interior with aluminized mylar to make an radio-frequency shield that protects the most sensitive components from stray radio signals.

(right) Brad keeps receiving bulk shipments of 5lb candy bags from an anonymous sender for the team. Much of this work is fueled by Gummy-calories. Thanks, whoever you are! (Yes, Amazon delivers to the South Pole through the USAP postal service).

Saturday Dec 3, 2016 - Let the first cool-down begin! (posted Dec 4)

It’s been a busy week - with all our cargo in hand since Monday, we’ve been scrambling to put it all together. We typically gather at 8am to outline the day’s tasks and divvy up responsibilities. We trek out to the telescope (about a km walk) and work three blocks (morning, afternoon and evening), jogging back to the station for our meals. We scoot back around 11 or 12 pm to catch a little communications time through the satellite (that’s how these blog posts get to you!), and check in with the rest of the team back north, before sleeping and starting over.

After 6 days of scrambling, we’ve reached the first milestone - the SPT3g camera is assembled! The next steps are to pump it down to a good vacuum (this takes about 2 days), and then begin cooling it, which takes another 5 days. This gives us some time to catch up on everything else and put our ducks in line for the first system tests that will start as soon as its cold.

Here are some photos of the instrument and team.

The focal plane of the South Pole Telescope 3g camera. Presently we have installed 2 of its ten detector modules (the white arrays, with electronics sitting behind). Each of the white items, barely discernable in the photo, is a pixel. The white object is a small lens that focuses light down onto a small, micro-fabricated antenna. There is one antenna for each polarization of light. After the antenna, the electromagnetic wave travels down a trace and is filtered according to its wavelength. The energy from the a particular color, of a particular polarization is deposited on a small piece of metal - a superconductor held in its transition - which heats up. We measure the temperature change of the superconductor and use this to figure out how much light is coming from a particular region of the sky. The superconductors are kept at about half a degree above absolute zero and the temperature changes are small - micro-degrees.

Sunday Dec 4, 2016 -- Antarctic Running (uploaded Dec 6)

Sunday Dec 4, 2016 -- SPOT update  (uploaded Dec 6)

My run took me out past “The End of the World” - this is where the fuel is stored in train tanker-like vessels that are mounted on skis - well away from the station, just in case the unthinkable should happen. In an upcoming post I’ll take you on a tour of the South Pole Power Plant, which burns about 48 gallons per hour to keep the electricity (650 kW - about 1 CHIME!) flowing that is needed to power the Station’s science and operations. (pop-quiz for my former Energy and the Environment students - do you think the station needs to spend any energy at all to heat itself?)

Any-night December, 2016 (posted Dec 22)

After trudging back from the telescope after working late, despite being dead-tired, it’s not always easy to turn a switch and sleep. Fortunately, the South Pole Station is equiped with a Sauna. (what? The coldest establishment on earth has a sauna? - isn’t that wasteful? No, not really. The sauna is in the middle of the building. Sure, a lot of energy is spent to heat it up, but when that heat escapes, it escapes to the rest the building.).

Our crew will often head to the sauna late at night, to chill out before bed. But no sauna is complete without a pole run. A half-hour or so in the sauna, then straight outside (don’t forget your shoes), and a sprint to the geographic pole in your skimpy’s.

Dec 12-20, 2016: Commissioning the SPT3g Camera (posted Dec 22)

The last week+ has been a whirlwind of activity. The camera cooled to its base temperature Monday morning, December 12, a little ahead of schedule. This was the fastest cooling to date, and caught us off guard by half a day (we were recovering and cleaning up after the Sunday evening open house telescope dance party that has become a tradition, once a year, at the telescope. It’s our way of thanking the station staff for their help and support this season -- more on that later). We scrambled to cable-up and turn on the various systems that control and tune the camera -- and started sleeping a whole lot less.

Ready for blast-off! The SPT3g camera, pointed straight up, ready to be hoisted into the telescope cabin for a test fit. It took 11 people a full day to successfully lift and mechanically install the camera in the cabin. The camera is huge and the optics system makes use of all the space in the cabin - at some points, there’s an inch or less of clearance between the cabin wall and the instrumentation. Parking the camera on its mounting points is like trying to park a Winnebago in old Montreal. We did have to remove the cables to get the camera up, but once in place, we were able to cable it back up and it all fit.

Summer Solstice December, 2016 - McMurdo Station, Antarctica (posted Dec 25)

**: The PM-3A nuclear power plant was erected in February 1962 by the Navy and turned on in March (wow, I wish we could commission a telescope that fast!). It produced 1.8 MWatts at 72% availability. It was shut down in 1972 (I think the Antarctic treaty forbids nuclear reactors), and the site was fully decommissioned and released for use in 1979.