Bernard Fleck has told me the story of that day. Sounded like an intense experience for everyone there!

Great news! I bet it’s going to be nervous and exciting few days for you and the team.

I will also (soon) post a link to a Jupyter notebook which contains an example Cryo-NIRSP spectrum and the fitting routines for those interested.

I made use of a package called JAX, which is primarily for Deep Learning but can speed up optimsation problems. Well worth checking out.

13/13

In the next post in this series, I will delve into the results in more detail. I will give a glimpse of some of the science possible with Cryo-NIRSP, with a focus on waves in the corona.

12/n

The modelling results are excellent! The data is fit extremely well which means we can extract the details of the coronal line profile (in purple).

While maybe not that exciting by itself, once we repeat this for all the spectra in the data set (over 6 million!), we get some fantastic results.
11/n

To get the infromation we want, we have to model the spectrum and extract the coronal profile. This is technical, and for those brave of heart, described in Schad et al. 2024 arxiv.org/abs/2402.09632

10/n

The dips at different wavelengths (and even where the coronal line is) are due to scattered photospheric light and absoprtion by water in the Eath's atmosphere.

Here I indicate locations of the photospheric lines and their potential source. These lines are taken from a modelled spectral atlas.

9/n

Turns out the corona was there after all! The bright strip near 1074.7 nm is a coronal emission line (Iron XIII).

The details are best seen by plotting an individual spectrum. The coronal line is indicated by the arrow.

There is lots of other information in the spectrum, not all of it wanted!
8/n

Cryo-NIRSP is a slit-based spectropolarimeter, so we only get a narrow band across a fraction of the Sun (shown by red line in previous part of post).

Hence, each data file contains the results of a slit exposure, so is wavelength verus slit location. There are two beams, so two similar images.
7/n

The first step was to provide some context for the Cryo-NIRSP data. I used data from NASA's SDO and GOES SUVI, plotting the expected location that DKIST was observing over the top.

Cryo-NIRSP observed an open field region, catching an active region and a streamer base on either edge.

6/n

I forgot about the data while the Cryo-NIRSP science team did initial processing. And 3 months later I was sent the data files. With trepidiation I dove in!

5/n

I then recieved the email saying the data had been taken 🥳

The team attached an image of the data, reporting they could see the corona....

My honest first reaction was 'What the hell?!?' 🤨

I didn't know what to make of it. I am used to working with pretty images, so felt a bit morose 😢 😂
4/n

I was fortunate to have a proposal accepted in the 2nd Observing Cycle. Needless to say, I was ecstatic 😁

It was a long 9 month wait until the data was actually taken. But the DKIST team were great at keeping me informed of preparations and discussed the details of implementing my proposal.
3/n

Getting access to Cryo-NIRSP data suitable for your science goals requires submitting a proposal during one of the dedicated calls. From what I can tell, this has been well subscribed, showing a great community interest in DKIST.

Existing gata can be accessed by the DKIST data center.
2/n

If you want to play with the solar spectral atlas, I have prepared a short Python notebook on how to do this: github.com/Richardjmort...

If you want to know more about Cryo-NIRSP, the instrument paper is at rdcu.be/d2WnH

The first results are given in a paper by Tom Schad: iopscience.iop.org/article/10.3...

What makes Cyro-NIRSP special is it can measure spectra fast (every 1s), with a high sensitivity, and a great spectral and spatial resolution. This combination opens up lots of opportunities that previous instruments could not!

In the next (extended) post I will talk about the data itself.

Cryo-NIRSP is a type of spectrometer. Its focus is on measuring coronal spectral lines that are found in the infrared.

It provides multiple spectra at different positions along a slit, so can focus only on a narrow strip of the Sun at any one time.