In the calendar today is a graph that is very important for the thorium fuel cycle...
Today I give you ETA!
ETA tells us about how many neutrons you get out for each neutron going in (to a nucleus) on average ("neutrons emitted/neutrons absorbed"). As you can see you get, on average, more neutrons from fission of uranium-233 (red line) than you get from plutonium-239 (blue line) - if the neutron going in has low energy/is a thermal neutron.
So, since uranium-233 is a better fissile material than plutonium-239 (when hit by low-energy neutrons), you can produce more new fissile material from thorium, than you can from uranium 😀 We like that <3<3<3
In Berkeley it´s 3 PM December 10th, so it´s not too late with todays calendar graph 😉
In the calendar today is a very important and very preliminary plot - of the gamma ray strength function of uranium-234. Inside the heart is a little "bump" that is actually really important, and you will get a much better plot of this later (when the analysis is finished) - and also an explanation of what it is...but be patient, and remember that the advent season is about waiting 😉
In the calendar today there´s a super nice graph I didn´t make myself, but I have of course made it even prettier than it already was 😉
Todays graph is a so called "cross section graph" for uranium-235.
The cross section sort of tells us about the probability that something will happen to a nucleus; in this case it´s about the cross section/probability that uranium-235 will fission <3
On the x-axis is the energy of the neutrons hitting the uranium-235 nucleus, and on the y-axis is the cross-section. As you can see the cross-section is much bigger for low energy neutrons than for high energy neutrons - this means that there is a much much bigger probability for a nucleus to fission when it is hit by a neutron with really low energy.
Since I´ve sort of travelled through time (at least that´s what it feels like) and now am in Berkeley I though todays advent calendar should be about why I´m really here 🙂 So today i give you fission!
Yes, again its´fission of uranium-234. This time its´gamma radiation from fission (there is always gammas when a nucleus fissions, and here you see 765 914 gammas at one time xD ), in opposition to a couple of days ago when I showed you particles from fission.
Both of the axis are energy: The x-axis is gamma-energy (so energy of the gammas that are emitted), and the y-axis is excitation energy (energy of the nucleus before it fissions - the nucleus gets so excited that it just has to split in two 😀 )
PS: I think time is very fascinating... here is a picture of me in on of SAS´ time capsules, just after we reached Canada. I´m looking down, around 12000 meters, at snow, and ice, and snow, and snow, and ice 😛
PPS: I think it´s just EXTREMELY fascinating and almost crazy that we can actually get a plane in the air - love it <3
Good morning the sweetest readers in the whole world <3
In this moment I´m at Gardermoen airport (again 😛 ), soon ready to go to Copenhagen and then to San Francisco (and from there to Berkeley). Since I´m going to spend quite some time in the air today - around 13 hours in total, or something like that - what could possibly be be better in todays calendar than a pretty dose/altitude graph?
I´m guessing nothing...;)
This graph is a little average, since the dose you get when you´re up in the air is a little different depending on where you´re flying (the dose is higher when you get closer to the poles, and lower when you get closer to the equator), and if there´s a lot of solar activity (more solar activity equals higher dose 😉 ). Anyway; let´s say I´ll be spending 13 hours at 35000 feet (35 kfeet) today, I´ll be receiving a dose of 52 micro Sievert 😀
PS: I´m much more worried about turbulense than radiation 😉
And now there´s only 17 days left ´til christmas...!
Today I´ve been working all day, and the rest of the evening I´ll be working a little more, and pack my bags to go to Berkeley tomorrow *excited*. But of course I have to share a graph today as well 😉
In the calendar today there is a typical "banana plot". The "bananas" are different particles, with different energies (energy on both the x-axis and the y-axis - they show deposited energy in two different detectors). The biggest banana is made out of protons, the middle one is from deuterons, and the upper one is made out of tritons.
(For the ones that are really really interested, the plot comes from uranium-234 and a 12.5 MeV deuteron beam 😀 )
Since it´s Friday (again!) I want to show you some fission <3<3<3
Here´s a super pretty graph of uranium-234 fissioning 😀
Yes, there it is! The red "banana plot" are particles from fission. Super cool stuff. (Edit: I wrote gammas, and not particles, first. That was wrong. It´s just that I´ve been working on gamma plots all day... )
So today´s December third, and today I´m giving my readers a not so pretty picture (but it has a very nice snowman, though <3 )...
Here´s what happens when I actually try to make everything very nice and clean (the 8 graphs are supposed to be more or less exactly on top of each other...) - but then f*** up (obviously).
I know what I´ve done, and I´ve double checked my calculations, and actually can´t really find any mistakes (even though they have to be there). Something like this will almost always happen, and that´s why you keep an "ORIGINAL"-file, with the last numbers and calculations that actually made sense (you may have to learn this the hard way :P). So for me it´s not back to basics *relief*, but back to the version of the program that made results that actually looked quite good - at least compared to this mess.
The good thing about this graph is that it´s not difficult to see that something´s "off" *staying positive* 😀
Bak luke nummer 2 i SunnivaRose-adventskalender skjuler det seg....*trommevirvel*:
EN ØDELAGT DETEKTOR! Eller, i alle fall én strip på én detektor som det er noe galt med - ingen tellinger overhodet er lik noe er galt 😛
Sånn kan det altså gå, og det er derfor det er veldig viktig å være tålmodig og gjøre et skikkelig og møysommelig arbeid - når 64 (!) detektorer skal sjekkes. 1 av disse 64 har altså ikke detektert ("talt") noen ting; vet ikke hvorfor, men akkurat nå bare vet jeg at det er sånn, og så får jeg finne ut av hva det faktisk er etter Berkley, før resultatene skal publiseres... Sånn er forskerlivet 😉
(Dette er forresten samme type plott som bak gårsdagens luke, der vi så at det var en av strippene på en av detektorene som ikke var skikkelig kalibrert. Mao så vet vi/jeg at 62 av 64 detektorer ser ut til å være gode, og så er det 2 det er noe "galt" med; og, som sagt, hva tar vi ikke nå når det er et såpass stort press på å få frem noen foreløpige resultater til neste ukes workshop 🙂 )
I dag ønsker jeg alle generelt, og lillesøster Carina spesielt, masse masse masse lykke til på EXPHIL-eksamen <3
Selv tok jeg EXPHIL først da jeg var godt i gang med å skrive masteravhandlingen min - så for min del var det lite "forberedende" over det... Skal ikke gå inn på hva jeg tenker om kurset, men, vel, jeg utsatte i alle fall å ta det så mye jeg absolutt kunne (det var den aller siste eksamenen jeg tok før jeg hadde mastereksamen).
Siden november er over er det lov å høre på denne igjen; Maria Mena "Home for Christmas" - en av mine favorittjulesanger, tror jeg 🙂