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Publisert 2 kommentarer til Facts on a Friday: 10 reasons why neutrons are really cool
Today I just wanted to tell you a little bit about neutrons, and why I think they're the coolest. You know, in a way they're like a Chanel purse - classical, and never out of style 😉
speaking of Chanel: I've been thinking that I should buy a black Chanel purse as a gift for my self when I have finished my PhD, but maybe I should consider the pink one instead...?
So here are my ten reasons why I think neutrons are really cool:
  1. Neutrons have no charge
  2. They decide if an atom is stable or radioactive
  3. A single neutron can sneak its way into a nucleus and make fission <3
  4. It's an unstable particle with a half life of a little bit more than 10 minutes
  5. I sort of envision them as white dots, or tiny billiard balls...
  6. A free neutron turns into hydrogen (meaning that the neutron is actually a radioactive particle - radioactivity is just soooo fascinating 😀 )
  7. Neutrons are the "flame" in the fuel of a nuclear reactor
  8. Neutrons gives different doses (of radiation) depending on their  energy 
  9. You can make a neutron from a proton and a proton from a neutron (almost sounds like witchcraft, or something)
  10. If neutrons have the right energy, they can do quite a lot of damage - but you can just use normal water as a shield, and you're fine 😉
I just love them - neutrons are without doubt my favorite. They're fabulous ✨

Do you have a favorite particle?

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PS: I am working on Question of the month (which is actually not a nuclear physics one this first time) - the plan was to publish it yesterday, but since I (unfortunately? 😛 ) have another job than just being a blogger, I haven't been able to finish it yet , and I'm really sorry :/ However, I'm still inside my own "limits", since I said it would come this week, and even though it's Friday, it's not the end of the week just yet 😉

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Publisert 8 kommentarer til Upset and annoyed

 

Today I was part of the "panel of scientists" on Abels Tårn - the radio show that airs on Friday mornings at NRK P2 (this particular show will not air until December; probably December 4th). This time was sort of a "special edition", where the audience were all high school students (and their teachers), and all the questions were from these students.
So far, so good: GREAT FUN! (For the first time, I was on the show together with Anders - that didn't make it any less fun <3 )
After the show, one teacher came up to me (at least I think tha's what she was), and told me she had two questions. 
Great, I thought...
But  they weren't questions, they were more like "questions":
The first one was if a Molten Salt Reactor will release less radioactivity during normal operation than today's reactors, and the second one I'm not sure if she ever asked; except she was asking me about all these Germans that had written stuff in German, and I said (several times - at first I was polite) that I don't speak German, so, no, I have not read these things (but I should, according to her). She was laughing in my face when I said that there are no radioactive releases during normal operation of reactors even today (and of course not in the future), and just told me I was wrong (and said that if I just read these German things I would know that I was wrong...). Still I didn't just leave (that would be rude), I tried to talk about radiation doses and limits - it wasn't very successful.

This teacher pretended to have questions, but was not interested in listening to what I said, and just went on and on and on about new German titles that I should (have) read. It was annoying and rude, and I'm still kind of upset, actually :/

all photos: Yngve Vogt

Maybe the worst part is that this teacher (if that's what she was) was stealing time from the students that had several questions for me, and that I would really have wanted to talk to - not to tell them so much about nuclear physics, but about science, and research, and all the amazing possibilities...
BTW: Thank you so much to the student who just wanted to tell me that she really enjoyed my TEDxOslo talk <3 The talk from LeRosey, last year, is HERE, and the one from Bergen, a couple of weeks ago will come very soon (stay tuned).
PS: It's TOTALLY OK to disagree with my view on nuclear power, but please don't pretend to ask me questions when you have no intensions of listening to what I say, and not respect me as a scientist. I try very hard not to pretend to be an "expert" on stuff taht I'm not working on, so don't pretend that I know nothing about my own f*****g field of science. Thank you <3 
PPS: Besides the behavior of this teacher, it was a great day, and I had a lot of fun being part of Abels Tårn today!

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Publisert 2 kommentarer til Nuclear force, nuclear power…

One thing that is kind of funny is that in Norwegian the word for "nuclear force" and "nuclear power" is the same - "kjernekraft".
It's the same word that describes the force that holds the atomic nucleus together and the way of producing power by splitting atoms. So in Norwegian you just can't be against kjernekraft, because it makes no sense: If you're against kjernekraft you're against atomic nuclei, and basically more or less everything, since there is nothing bigger than elementary particles - there wouldn't even be bigger particles like protons or neutrons, since they are made up from quarks that need kjernekraft to exist...
(PS: Of course I'm not really that pedantic - I do understand what people mean when they say they're against kjernekraft. But as I've said earlier, I actually don't understand how it is possible to worry about climate change, and not be pro nuclear, so I guess in a way I'll still say it makes little sense to be against kjernekraft 😉 )

no flowers, no sun, no sunset without kjernekraft...

#thinkaboutthat
#tenklittpådet

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Publisert 2 kommentarer til Ten facts about nuclear weapons and the "Megatons to Megawatts" program

Friday again!

This week that means Bergen, and as (almost) always that means FACTS. This week I want to give you ten facts about nuclear weapons and the "Megatons to Megawatts" project - a little "taster" of what my talk tomorrow will be about (I don't know if there will be a live stream yet, but at least the entire confernce will be filmed, and go on-line later - I will of course share the link when it's ready 😉 )

 

  1. nuclear weapons have been used against humans two times; Hiroshima August 6th and Nagasaki August 9th, 1945 - hopefully NEVER again
  2. both "Little Boy" and "Fat Man" were fission bombs (getting their energy from fission); "Little Boy" was made of highly enriched uranium (uranium-235), and "Fat Man" was made of plutonium(-239)
  3. after WWII a nuclear arms race begun between the US and the Sovjet Union, and at one time there were more than 60 000 nuclear weapons in the world
  4. a nuclear weapon is ugly, but by mixing the fissile material in it with uranium or thorium, it can be changed into beautiful nuclear fuel (100% normal nuclear fuel for normal reactors) <3
  5. the "Megatons to Megawatts" program was an agreement between US and Sovjet/Russia that lasted from 1993 to 2013, where Sovjet made fuel out of their weapons (unfortunately not all of them) and US bought it
  6. during those 20 years (1993-2013), 500 tonnes of highly enriched uranium, from 20 000 Russian nuclear weapons have been converted into nuclear fuel and "burned" in reactors (more than 2 weapons destroyed every day!)
  7. the electricity generated from these weapons is the same amount as all the electricity in the US in two years(!)
  8. weapons uranium (highly enriched uranium) could be mixed with natural uranium to make fuel (as has been done in the program) - or, even better, with thorium
  9. if you mix weapons uranium with thorium, you can also recycle the spent fuel; this means that not only do you get rid of horrible weapons, you also get rid of a lot of nuclear waste (WIN WIN 😀 )
  10. today there are around 16 000 nuclear weapons in the world - much better than 65 000 (or whatever the peak number was), but still that's definitely 16 000 too many...:/
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(I bite my lip when I concentrate - haha)

 

 Now I'm soon off to NHH, where the conference tomorrow will be held, for sound check, and just "feel" the stage. And when I come back to the hotel again, Anders will be here! I'm so incredibly happy he could join me here in Bergen this weekend!!! We're here until Sunday afternoon, so hopefully we'll have time to actually experience something while we're here - any recommendations from my readers?
Anyway: happy weekend to everyone <3

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Publisert 1 kommentar til Trinity, Little Boy, and Fat Man
Today is the last day of August - last day of summer 2015.
This August marked the 70 year anniversary for the end of WWII, the very first atomic bomb testing, and the first (and hopefully last!) time nuclear weapons were used against humans.

 

This picture is of Trinity - the first ever test of an atomic bomb/nuclear weapon. The picture is taken around 1 hundredth of a second after detonation of the bomb. The big grey thing is actually a fireball, which is around 200 meter in diameter. Inside the pink circles are trees. Trinity was tested on July 16 1945, and it was the same kind of bomb as the one in Nagsaki (on August 9 1945) - called Fat Man - except it was a little bit smaller.
Little Boy was a uranium bomb (made of highly enriched uranium), and Fat Man was a plutonium bomb (made of plutonium that they produced from natural uranium in a reactor). Together they destroyed the cities of Hiroshima and Nagasaki, and killed around 130 000-250 000 people...
When an atomic bomb explodes, the nuclear force is released, and that is why they are so powerful - and even though it is a horrible and really scary device, it is also extremely fascinating (the nuclear force, that mostly is responsible for keeping all nuclei everywhere together, IS fascinating). Often people believe that nuclear weapons are dangerous because of radioactivity, but it is mainly the extreme explosive force, and the heat that kills people - not radiation.

 

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Last year I went to Japan to make the short film Sushi and Nuclear (Sushi og Kjernekraft). Going to Hiroshima and actually see the Atomic Bomb Dome made a very strong impression... You can see the English version of the film HERE, and the Norwegian version HERE.

Publisert Legg igjen en kommentar til Fission on a Friday – 10 facts
It’s been a long time since I did a “10 facts” blog post (last one was about heavy water) - too long, I think, so it’s about time I do it again now 😉
I can’t promise there’ll one every week (I’ve tried those every week kind of blog posts before, and there’s always some reason - like my PhD work - why it’s difficult to see it through ), but it would have been fun if 10 facts could be like a Friday thing. Anyway, we’ll see how it goes, but today is Fission Friday; here are ten facts about fission:
  1. fission is when a (heavy) nucleus splits into two (lighter) nuclei
  2. an example of fission is when uranium-235 is hit by one neutron and becomes barium-144, krypton-90, and 2 free neutrons (same number of particles before and after fission: 1+235 = 144+90+2 = 236 :D)
  3. the light nuclei (like barium and krypton) are called fission products
  4. fission can be induced, which means that it happens because a neutron hits the nucleus (like in the picture) - a little bit like the neutron is a knife that cuts the nucleus into two pieces <3
  5. fission can be spontaneous, which means it just happens - no neutron or other particle hitting the nucleus - the nucleus just suddenly splits
  6. fission is my favourite decay mode (I think) <3<3<3
  7. a nucleus that will fission when it’s hit by a neutron is called (a) fissile (nucleus)
  8. the energy that is released in fission (when one nucleus splits) is 200 mega electron volts - which is the same as if 50 million carbon atoms burns and produces CO2 (yes, 1 versus 50 million to get the same amount of energy!)
  9. most of the energy released in fission comes from kineticc energy of the fission products - which is energy from motion of the fission products (they are moving fast away from each other)
  10. I think the energy release in fission is really really fascinating
If you think it's a good idea to do more "10 facts" blog posts, please tell me what you what you want to read about <3

Ok, I gotta run now, to catch my flight back to Oslo - since I've been giving a talk about motivation for science in Bodø today. If you follow me on Snapchat (sunnivarose), you can see the super cool LEGO rose i got after the talk (the talk was for First Lego League, so it was 100% right to get a rose made out of LEGO :D).

Publisert Legg igjen en kommentar til OSCAR #happy
So we just finished our group meeting, and let me just say YEAY!!!! The group meeting today was really nothing else but drinking Cava and eating (a very rich) chocolate cake (all meetings should be like this 😉 )...
The reason? Today it's official: the Norwegian Research Council has approved our application for new detectors at the Oslo Cyclotron Laboratory ❤️ We are getting 21 million NOK for replacing all of our old sodium iodide detectors (CACTUS - may you rest in peace), with new lanthanide bromide detectors (OSCAR - we welcome you!).
Read more about here (we are the "NEW GENERATION SCINTILLATOR DETECTORS FOR NUCLEAR RESEARCH IN NORWAY")
This is soooo exciting - experiments in Oslo will be better in aboslutely every way! 

Publisert Legg igjen en kommentar til Nuclear physics *heart*

Nuclear physics is often thought of as nuclear power, but nuclear physics is really the investigation and understanding of (atomic) nuclei, and nuclear power is just one of the applications of nuclear physics. 
The nucleus (that we study) is the heart <3 of the atom, and it's where almost all mass of matter resides. Nuclei consist of neutrons and protons; ranging from the smallest one ("normal" hydrogen) with just one proton (and zero neutrons), to the biggest with a few hundred neutrons and protons. (You can't make a nucleus with just one neutron, you have to have at least one proton). The nucleus is small, but large enough to do stuff like vibrate and rotate (what the nuclear physicist would call "show collective degrees of freedom").
A major motivation for studying the atomic nucleus is to gain a fundamental understanding of our world; its origin and future, and its current state. Nuclear physics can explain how stars work to release more or less all the useful energy in the world, while they at the same time produce the different elements - from hydrogen to iron. (Therefore there is today a lot of collaboration between nuclear physicists and astrophysicists.)
In addition to nuclear power, nuclear medicine (medical diagnosis and treatments) is another important application of nuclear physics <3 <3 <3

Publisert Legg igjen en kommentar til Getting there…
My talk is tomorrow.
It's not finished yet.
I feel nervous, but also excited...
Nervous, because I wish I had come further than I have, and that I understood "everything". Excited, because I actually do have results, and they are nice, and they make sense. They make me believe that I will actually do this; not just the talk tomorrow, but I will finish my next paper (article/publication) in June (or maybe July - but hoping for June). After that I will start directly to analyse the second part of the uranium experiment, and hopefully it will be much "easier" since I have already done it once 😉 
I'm in my bed right now, working on the presentation for tomorrow, which is around 11. Think I will work for around 30 more minutes, and then go to sleep. I'd rather get up at 5 tomorrow morning, and finish it then.
Wish me luck <3

Publisert Legg igjen en kommentar til #oslogamma
Good morning everyone <3
I'm at the University, attending the second day of the "5th Workshop on Nuclear Level Density and Gamma Strength" - the conference/workshop that our research group is arranging. Nuclear Level Densities and Gamma Strength (Functions) are fundamental properties of the atomic nucleus, and they are sort of the main goal of my data analysis just now.
I think my favourite talk so far was the one called "Neutron capture cross sections for the astrophysical r-process" by professor Artemis Spyrou from Michigan State University. Nuclear astro physical applications are really exciting <3 Unfortunately I missed the first talk this morning (stupid rain), which was by Luciano Moretto - I really regret this, because he always gives great talks...:/
Anyway; I'll be spending the rest of the week in this same auditorium, listening to talks - together with around 60 other nuclear physicist from around the world (West Coast of US, South Africa, and India, for example 🙂 )
I just realized that a hashtag has occured; #oslogamma! I don't think it will be the most popular hashtag on twitter, but at least it's there, if you want to follow 😉
Ok, now I have to pay close attention to all the talks - or, if there's something I don't understand ANYTHING of, I need to prepare my own talk that I'm giving on Thursday. Also, I need to work more on the actual analyzis of my data, so that I have more than just one plot to show...that would be a very short talk 😉