Hello good people! Are you ready to read lots of science? Because today I'll be describing my research in more detail.
So, let’s get right to it. These past two weeks I’ve been working with a grad student, Nengyi, on the more advanced section of my project. In this part, I’m looking at the data that’s been gathered and trying to find interesting trends. Specifically, I’m finding an approximation of the total redshift at specific points based on spectrograph data, which tells us how the plasma at that point is moving. By studying this redshift we can see how the flare loops move, and whether there’s anything interesting to analyze there. This involves the data from the IRIS satellite, which has a built in spectrograph. A spectrograph separates light by its frequency.
Because different elements put out different wavelengths of light when energized,
we can isolate specific elements and analyze their bands. Here’s an example of the
different bands for some random elements (sadly there’s no magnesium, which is what I’m using):
See how the bands are very clear? That’s what happens when the element is still. However, because of redshift, when I actually get my images it looks more like this:
The waviness of the lines comes from the redshift. Each horizontal bar corresponds to a pixel on an actual image of the sun. IRIS has both the spectrograph and a camera that shows where the device is looking. Here’s a picture of that too:
The vertical line in the middle is where the slit is. I have them scaled differently here, but in reality they’re the exact same number of vertical pixels. This helps us know what exactly we’re looking at. We can pick a specific pixel on the slit jaw image (the image of the sun) and then get the exact distribution in the spectrograph along the x axis. This tells us how the band is distributed on that pixel, and through that we get information on the redshift, because we can compare that data to baseline spectra. An image following is a plot of the data along the x axis for one of the points, showing the two peaks that are also visible in the entire spectrograph image.
Using this we gain real world redshift data, as opposed to relative. In addition, there are multiple ways to analyze the spectrograph lines, while their shape also tells us about the kind of motion.
For the current phase of my project, I’m just going to be looking at one point on the flare over time, and graphing that. Then later I’ll move on to the entire spectrograph slit over time, and I will see whether there are any interesting trends in that. Right now, though, I need to automate the method for finding the redshift so I don’t need to go through it manually every time. That has been my focus for the time being (there’s a lot more intricacies to the process, but that’s a bit much to get into; I swear it’s not as simple as it sounds here, though)
The group meetings are still happening every Thursday. I’m starting to understand them more, so now I can actually provide summaries! The group meeting in the second week was a person from the department presenting on a paper they had read about using a specific sensor array to look at and model sunspots. The first section described the accuracy and parameters of how the telescopes were set up. It couldn’t look at the entire sunspot all at once (sunspots are really big!) but there’s a set scan pattern so that the the telescopes can still capture the entire sunspot. The second section was the analysis, where they took the images they got and tried to draw conclusions. They were mostly concerned with the relative brightness in different wavelengths, which are produced in the different layers of the sun. They compared their data to what was predicted by different models to see which one fit best. I asked two whole questions!! They were mostly clarification, because whoever made the graphs didn’t label their axes (well it was a histogram so the y axis was just the number but still).
The third week, the presentation was actually in the Big Bear Solar Observatory, which the department runs. We could still see it here in New Jersey, though, as we were pretty much skyped in to the meeting. A guy at the observatory was presenting about his work on automatic filament detection. It was really cool and I actually understood a lot of it because it involved a lot of computer science and image processing. He used some cool image processing stuff to recognize when separate pieces of filaments were actually the same one. He also did analysis of the individual filaments in order to see the direction of flow. Then, he did a global examination of brightness differences between the filaments and the area around them to try to find how many of them were in active regions or sunspots and how many occurred elsewhere. This is still in progress, though, as the automatic detection didn’t fully match up with the recorded data. Sadly because it wasn’t in the same room I didn’t ask a question this time. There’s always the next one though!
Life outside the lab is going well, though it’s rather uneventful. I found a Whole Foods in Newark, which honestly surprised me. But it exists, is slightly closer than ShopRite, and has a much better selection of fruit. This may be a contributing factor to why I’ve bought around 15 mangoes in my two trips there so far. In my defense, they were on sale, and I really am eating all of them. I haven’t really been spending much time in Newark itself on the weekends, as I’ve been doing a lot of stuff with friends. I visited one who lives in Pennsylvania, and met up with some others in NYC. As I mentioned in my last post, New York is a pretty great city. I really like how sparkly and safe-looking everything is, although my impression might be a bit biased because I’m used to Newark. Because this section of my article is rather lacking in photos, here’s an extremely cliche shot of the World Trade Center that I took while walking around one weekend. I feel like it really exemplifies the sparkliness of the city:
One weekend I went to see the new Incredibles movie with my new dorm friends. It was a really good movie, would recommend, except for the part where (spoiler alert) the most relatable character is evil. My new friends are pretty cool, most of them are also interns (albeit college ones) and I’ve been having fun getting to know them.
Overall, everything is going well! I’m going to meet with Ms. Cozine and Emma on Monday, which I’m sure will be interesting. I really don’t know how to end this so I’m just going to go now. Thanks for reading!
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