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A year in Japan

Why This

An adventure in a foreign land deserves constant updates for friends and family back home (Sweden and Europe).

Thor, God of…

Science stuff Posted on Fri, April 24, 2015 09:44:14

On Saturday the 18th of April there was an Open Campus day at Riken Wako. It was estimated that about 5 000 people visited the campus that day to learn more about science, research and the Riken Wako Campus. For us this luckily didn’t mean we had to clean the office. That would be a full time job for a couple of people for a long time. However, it did demand we each put together a quick presentation about our work and what we’re doing.

Since I’m now part of the JEM-EUSO collaboration and being Swedish I thought I would do a nice twist on the presentation. I was also told that the majority of the audience would be children. Given the popularity of the Marvel films I thought I could talk about the Norse God Thor.

Thor was the Viking God of Thunder and Lightning. He had a hammer which produced the lightning and when riding across the sky in his chariot it caused the rolling thunder.
(Copyright Marvel and all that stuff)

However, today we know that this might not really be the case. In 1749 Benjamin Frankling performed his experiment with the key tied to the string of a kite and in doing so proved that the lightning actually was electricity. Today we have quite a good grasp of how the actual lightning bolt works but there are, to many peoples surprise, still some mysteries regarding lightning. The main mystery is the we actually still have no confirmed understanding of how lightning actually can be created. Here’s some more physics…

In order for lightning, or a static discharge to occur the potential difference between two opposite charged objects have to exceed a certain threshold. If the electric field is higher a discharge can occur. This is exactly what happens when you reach for the door handle and just before you can grab it there’s a spark and your finger hurts. In order for this discharge to happen the electric field in air has to be higher than about 2 MV/m (Mega Volt per meter, i.e. 2 000 000 V/m). This implies that if the discharge occurring when you reach for the door handle happens when your fingertip is about 1 cm from it the lightning bolt will measure about 20 000 V.

Here’s the strange part, measurements which have been performed in thunder clouds show that the electric field is not even near being strong enough to support the lightning discharge that actually occurs.

One theory has been put forward which could explain the lightning even though the lack of electric field strength. The theory is referred to as the Runaway Breakdown, and is an effect of cosmic radiation hitting the atmosphere and creating an Air Shower (see earlier post).
The classical depiction of an air shower from an arriving cosmic ray

Studies of this phenomenon have so far not been able to disprove a connection between lightning strikes and the arrival of cosmic rays. In fact the results show rather the opposite, that there most likely is a connection between the two phenomena.

The JEM-EUSO collaboration will be studying this by observing lightning from the International Space Station and compare the lightning strikes with the detection of arriving cosmic rays.

So the JEM-EUSO collaboration will be able to answer the question if…

Thor was the God of lightning and thunder

or in fact

the god of cosmic rays…


Science stuff Posted on Tue, April 14, 2015 10:37:44

After having built a UV filter for my camera I was able to confirm that we should, without any problems, be able to see stars in the night sky. After some small adjustments to the telescope, the stars suddenly appeared and we were all very happy to see them.

Our hope is obviously to be so lucky that we will be able to observe an Air shower. However, in order to run, we first have to learn how to walk, and before we learn how to walk we need to learn how to crawl. Basically what we just had done was making an attempt to sit up.

Located about 20 km from our telescope was a powerful laser. This laser was aimed in the zenith direction and could fire multiple bursts of laser shots into the night sky. Given the inclination of our telescope we have a time frame of about 20 µs during which a laser pulse is within our field of view. 20 µs is the same as 0.00002 s, i.e. you can have 50 000 such time frames, back to back, in a single second. This might sound very fast, and it is, but it’s no problem for our detector. The timing resolution of the telescope is 2.5 µs i.e. we should be able to see a single laser pulse in about 8 frames.

At the moment our telescope has no internal trigger, this is actually what I’m working on at the moment. So in order to see the laser we needed the trigger from the TA-FD. A “trigger” is just a signal saying “it’s time to read out the detector”.

A very intense wait followed after we were ready to try to observe the laser shot until it actually was time for the laser to fire. The seconds ticked by slowly, really slowly. But suddenly the screen started showing output that the detector was triggering the readout and shortly thereafter we could start looking at the data…

And there it was, we could clearly see the laser pulse ascending to the night sky across our field of view!!

This might not seem as much of a thing, although being able to show that we can see the laser proves that the detector principle is correct and that we’ve built it correctly! An email with the data was soon sent to the collaboration and shortly thereafter congratulatory emails started dropping in from the PIs (PI is Principle Investigator i.e. Boss) from all over the world. Below you can see how the laser pulse ascends across our focal surface on the way into the night sky.

(For some reason the gif doesn’t play so click here on it to see the animation.)

The EUSO-TA March 2015 campaign at Telescope Array could be classified as a success.


Science stuff Posted on Wed, April 01, 2015 18:09:02

I thought I also should write a bit about the work we did in Utah. Yes, we actually had time to do some work between all the sight seeing.

As I wrote last week, the reason we went to Utah was that it has good conditions to view air showers and that’s why TA – Telescope Array – has set up shop there. We have built a small detector in front of one of their optical telescopes. The main objective of our detector, EUSO-TA – Extreme Universe Space Observatory at Telescope Array – is to first show that the detector works, take measurements of two separate lasers which will be firing into the sky to simulate an air shower, take measurements on the night sky back ground and ultimately hopefully be able to observe an actual event. Now the last point is extremely difficult given how rare these events are.

This trip was actually the second campaign to Utah. The first was two years ago, and I was obviously not part of it. Although, as far as I know there was little success at that time due to problems with the electronics.
Above: Me with (R->L) the Black Rock Mesa FD Telescope, the EUSO shed and the Electron Beam Facility in the background.

When we arrived our colleagues had already been in Delta for about 10 days. So basically everything was already up and running. Although no good observations had been made.

The TA Florescent Detector (FD) can only operate during “dark time” which is night time when the moon has not yet risen. We had planed to start our work before dark time so that we could run around outside the control room with flash lights without disturbing TA operations.

We started the observations by trying to see blinking diodes and a high powered hand held laser, see picture.
Yes, I know. It does look like a light sabre from Star Wars.

We also tried to observe stars but we had some difficulties in the beginning. Therefore Marco suggested I’d build a UV-filter using the same type of UV-filter we have in the detector for my camera. However, we only had UV filter pieces about 2×2 cm² and since the diameter of the lens is 77 mm I had to MacGyver together this:
And surprisingly enough it actually worked…
I did manage to see the stars when the filter was mounted on the camera. Unfortunately I do not have any good pictures of that at the moment. I’ll maybe update the post with such a picture later.

More to follow….

Fossil hunting

Travels Posted on Tue, March 31, 2015 08:31:36

Probably the coolest thing that Marco and I did before we started a shift one day was going fossil hunting. And to quote an old MASH episode “and I didn’t even know they were in season“.

We decided one morning, on the way back from the observatory, that we should try to get up early and head out into the mountains. We had checked the internet and found three different potential sites, one being an BLM quarry. BLM stands for Bureau of Land Management and this quarry was supposed to be free to use.

Later that day, after having slept for a few hours, we got the GPS coordinates and left the motel. The fist stop was a hardware store to pick up a couple of hammers and some other supplies and then we headed out.

First we drove along I50 for about 30-40 minutes at, well let’s just say that my crazy Italian Mario Andretti wannabe boss almost kept the speed limit. Almost being the operative word. Then we left the nicely paved road and started driving on dirt roads. This went on for another 40-50 minutes, again when distance driven is estimated the crazy Italian Mario Andretti factor should be taken into account.

After about an hour and a half into our adventure we had missed the final right turn. Fortunately we’d only missed it by half a kilometre so it was no big loss doubling back. However, when we saw the (now left turn) we realised why we missed it… To begin with it was a very small road and secondly it was going down a slope into a ravine. To add to the unease I was starting to feel about taking this road we not only had do drive down into the ravine but shortly thereafter we would need to climb out of it, yes I use the word climb even if it needed to be done with a car. Now this would not have been an issue if we’d had a real car, like a Land Rover, but our rental was a Chrysler 200 or something… Definitely not an all terrain vehicle…

We were still about 1.4 km from the BLM quarry and I was thinking maybe we should walk, but Marco insisted on trying to drive up the mountainous slope. Now in my mind there were two issues with this. The first being that the car would roll over and I would have to drag Marco out of a burning wreck. Yes, I got out of the car for his cross country experience. The second thing, setting aside the explosion risk since we had an American car, was that IF something happened to the car we would be without means of transportation or communication (no mobile phone coverage) and literally in middle of nowhere. Luckily luck was on our side, so far, and Marco managed to drive up the slope of the ravine and we could continue our journey towards the quarry.

After a very bumpy ride the GPS finally told us that we were in the right place. Unfortunately there was no quarry at the coordinates… However across another ravine we saw some potential places where we surely would find some rocks. If they contained any fossil was a later problem.
So we got our hammers and started walking. It was easy to get there and we started surveying the area. This was also the time that we realised that non of us actually had any idea of what we were searching for. I only knew that the rocks we were supposed to look for were black.

So for about 20 minutes we often called out saying that there might be one in this stone. However, we were probably just going slightly crazy and seeing patterns where there were non. But then, suddenly, I found the first jack-pot! In one small stone you could clearly see the remains of three different Trilobites (see three red arrows in the picture below).
After that find more fossils started to make them selves known and we found many more. The best find of the day was mine.
The fossils we searched for and found are in the vicinity of 521 000 000 years old.

After having spent about 1.5 hours searching for fossils we decided it was time to head back. Especially if we wanted to have time to visit a fossil store in Delta before we were to meet our colleagues. The drive back from the site was not as eventful as the trig getting there. Although, it might have been but I was so used to Marcos driving by then.

The fossil shop in Delta was very nice. Lots of cool fossils and a very nice owner of the shop. We spent some time looking around and talking but finally we had to go back to the motel to start the working day.


Travels Posted on Mon, March 30, 2015 10:32:03

Last week I offered a physics lesson talking about air showers and cosmic rays. Today I thought I’d talk a bit about history.

On December 7 1941 the Japanese Imperial Navy attacked the US Navy at Pearl Harbour in Hawaii. Up until then the US had been very hesitant towards joining the war (World War 2), claiming it was an European problem. However, after Pearl Harbour America joined the fight against the Axis (Germany, Japan and Italy).

The west coast of the US had a significant population of Japanese and/or American citizens with Japanese ancestry. Now being in war with the Japanese, this gave rise to a fear of acts of terrorism and or espionage on American soil. In February 1942, President Franklin D. Roosevelt’s Executive Order
9066 sanctioned the evacuation and internment of more than 112,000
people of Japanese ancestry.

On July 4th (“independence day”), 1942 the following information was posted
explaining that “[…] all persons of Japanese ancestry, both alien and non-alien, will be evacuated from the area […]”. The “evacuees” were not allowed to bring much of their property, basically only what they could carry them selves.

The people were evacuated to different camps inland called internment camps. In total there were 10 of these camps. One of the camps, called Topaz, was located just outside the town of Delta, Utah. Between August 1942 and October 1945 over 10 000 people lived in Topaz.
During the war, the Topaz internment camp was the 5th largest city in Utah.

One might think that being incarcerated like this would make you angry at your country. But the fact is that during the war the 442nd Infantry Regiment was comprised nearly entirely of volunteers from the internment camps. Not only did they volunteer to fight, this regiment became the most decorated unit, taking its size and length of service, in the history of the American warfare, including almost 9500 Purple Heart, 8 Presidential Unit Citations, and an amazing 21 Medals of Honour.

By the end of the war the camp was closed and the evacuees were sent “home”. The reality was that even though the evacuees might have had homes and lives before the war, non of that was left and they all had to start over from scratch.

What remains of the camp today is mostly the roads and a large number of artefacts spread all over the site. The roads are clearly visible on google maps: Topaz. The camp was divided into “Blocks”, each block with a number. The numbering started (as seen on google maps) with Block 1 in the top left. The four blocks in the centre were recreational areas with a temple and a base ball field.

Above: One of the roads in the camp.
Above: Remaining artefacts.
Above: What remains of the Baseball field (Block 24)
Above: Where the camp “church” was located (Block 17)
Above: Block 17.

Currently a new museum is being finalised in the town of Delta. This is a very nice museum and I can strongly recommend a visit if you (for some strange reason) find yourself in the vicinity of Delta.
Above(2 pictures): Topaz Museum in Delta, recreation of one of the barracks where the internees were living.
Above: Topaz Museum in Delta, original barrack, this housed a gym.

As can be seen in the pictures there is not much left of the camp site. However, there is a clear historical presence when visiting the site. You can really feel it when you’re walking around the site. The site is open and you are free to walk around. However, you may not remove any artefacts from the camp site.

Japanese people living on the east coast were not sent to the camps.

Probably the most famous internee during the war was George Takei, famous for his role as Lt Sulu of original Star Trek cast. However, he and his family did not stay at Topaz but at Rohwer War Relocation Centre in Arkansas.

For more information I refer you to the following sites
Topaz Museum
Topaz on Wikipedia
Famous people interned at Topaz
Internment project

Classy living

Travels Posted on Fri, March 27, 2015 10:45:51

Having arrived in Delta in the afternoon of Tuesday the 3 of March we basically just had time to check in to the Budget Motel where we had been recommended to stay by our polish colleague. This, and the fact that it was about 30 dollars cheaper per night than the other hotel I had been told we would be staying at (when applying for the visa waiver) should have given some indication as to the quality to expect…
However, surprisingly enough, the rooms were more than ok. I only have two bad things to say about the place. First, but I think this is common all over America, is the overuse of synthetic smells. Entering the lobby I was almost worried I would pass out from the intense artificial smell. Although, it was not as bad in the room. The second thing was the breakfast, or rather “breakfast”. It was served between 6:30 and 9. Which was convenient for us since we came back from a nights work at about 6:30-7. So we could have breakfast and then go to bed. However… I am not a big drinker of coffee and unless I have lots of milk in it I think it tastes very bitter. Although I can drink it black. Again, however… The black gooey substance which they tried to pass off for coffee was totally and utterly vial. Completely undrinkable. Matter of fact, I’m not sure that it actually was coffee, needless to say, I didn’t drink more than that first zip during the first breakfast.

After having stayed at the motel for a few days I realise I have something which looks like a bullet hole in my outer (plastic) window. The hole is funnel shaped with the small opening on the outer side and the large opening on the inside.
Now, to be clear, between me and the plastic plate with the bullet(?) hole in it, there was a glass window which did not have a hole in it. So this was not new since I arrived at least. I mean, you never know what some religious zealots can do to scientists (being in Mormon country)…

Assault, why??

Travels Posted on Thu, March 26, 2015 10:54:08

I travelled from Tokyo to Salt Lake City via Denver. After arriving in Salt Lake City, I was magically able to meet Marco at the airport. Marco had arrived about an hour earlier. The reason for this was that we belong to different frequent flier programs, so unlike me he had flown from Narita via Seattle to Salt Lake City.

In any case, after meeting, we got the rental car and started driving towards Delta. We had booked a hotel in the outskirts of Salt Lake City and with the help of the GPS we were able to find it.

After having checked in we went out to get something to eat. We found a small place just across the highway and I could order a steak. Now to be honest, as Marco pointed out afterwards, it wasn’t the best steak ever. But it was a steak… After being in japan for about 4.5 months I was so pleased to be able to sink my teeth into a real steak, and not having to pay half a months salary to do so… that I at the time, didn’t really care that much that the steak was a bit charred.

The following day the plan was to first make a stop at a Walmart to buy proper clothes for spending nights in the desert. However, when we got out of the hotel this is what we saw.
Being a Swedish viking I, obviously, had to play it cool and say “I’ve seen worse”. In any case, the closest Walmart was only a few miles away so we could hide out there until the worst of the weather had passed.

Walmart is more or less like your average large scale supermarket store where you can buy anything you need. And I really mean ANYTHING…

We spent quit a lot of time getting warm boots and clothes but eventually we were done and started to check out what else they offered. After having worked our way through the DVD/BlueRay and the Toys sections we arrived at the Fish and Wildlife part. Here’s where it get interesting…

First it’s a normal Fish and Wildlife section where you can get fish tackle, camping gear etc.. But the suddenly I turned a corner and was standing face to face with this cabinet
At first I thought they were toys, like soft airguns or such. But then I realised that they were actual assault rifles… Suddenly the following dialogue does not seem so far fetched:

– Honey, I’m just going to Walmart to pick up some milk and some candy for the kids. Do you need anything?
– I’m good. No! Wait, can you pick up a AR-15 assault rifle for me. I’ve been meaning to get one but haven’t had the time. I need it for the squirrel hunt this week end.

Or something like like that. I’m sure that you’re not allowed to hunt squirrels with an assault rifle, not even in the US… Her’s Jim Jefferies giving his take on guns and gun control. Definitely worth 16 minutes of your time, for two reasons: 1) He’s funny and 2) he makes good points.

In any case. We didn’t get any assault rifles. But we did lots of other stuff and by the time we had worked our way through the entire store the snowstorm had dissipated and we could more safely continue our journey towards Delta.

A nice Shower

Science stuff Posted on Wed, March 25, 2015 11:02:36

So, again it’s been aeons since I wrote something… One would think that I’m so busy that I don’t have time to write. Frankly I have no idea where time disappears to. Probably Netflix…

However, this time I actually do have some sort of reason for not having written, at least for a few of the weeks I’ve been absent. The reason is that we have been in the great metropolitan city of Delta in Utah. Delta is a city with a population of about 3 500 and is located 50 miles past nowhere, in the middle of the desert.

The reason for us being in Delta was that since it is located in the middle of the desert it poses great opportunities for astronomical observations. Therefore one of the larges air shower telescopes, TA – Telescope Array, is located about 30 minutes drive outside Delta.

An air shower is a cascade of particles created in the upper atmosphere when extremely energetic cosmic ray particles (mainly protons) collides with air molecules. The collision is so violent that the proton breaks into a very large number of pieces. As a result a light glow can be observed in the sky. Well… If you have a very expensive type of telescope.

The glow is mainly in the UV-range of the light spectrum (300-400 nm) and last for only a fraction of a second. Therefore you need the specialised telescopes to see them.

This type of telescope is actually what the project I’m currently working with is trying to develop. However, our telescope is not intended to sit on the ground looking up into the night sky. We want to place our telescope in the International Space Station, looking down onto the night sky. In doing so, we will be able to observe a very large area. This is needed because the interesting particles (the ones with the highest energies) are extremely rare. The arrival rate is about 1 cosmic ray particle per 1 square kilometre per 100 years.

That means, if you have a 1 km² detector, it will take you on average 100 years in between seeing the interesting events. In order to collect lots of data you can either measure for a very long time or build a very large detector. Actually, you would like to do both…

So, by going into space we can increase the size of our detector volume (the atmosphere -> detector area) and we also gain the additional benefit of not being stationary, only viewing either the north or the south sky. We get what we call full sky coverage.

Most of you have probably given up already so I’ll stop for now. But I’ll continue writing about our trip to the Utah desert.

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