M101 writeup
The M101 writeup is more than just another homework assignment, it
is a holistic presentation of a research project that goes from raw
data to scientific understanding. You should focus not only on
getting the technical analysis correct, but also on framing the
scientific background and previous work, presenting your analysis in
a through and clear manner (written descriptively in words, not in
math and code), and interpreting your results in the "big context"
of galaxy evolution and how it fits in with other studies. Think of
it as putting together a complete scientific story that describes
not just your specific analysis, but shows also how it fits into and
contributes to the overall context of astronomical research on
spiral galaxies.
Paper Format:
The format for your writeup should be that of an
Astrophysical Journal paper. The following elements are necessary
(page lengths refer to single spaced 12-point font, with 1-inch
margins):
1. Title/author
2. Abstract: a short
paragraph summarizing the goals, results, and scientific
implications of your project.
3. Introduction: ~ 1.5-2
pages of text, giving the scientific context: what is it that you
are studying, why is it scientifically important, what have other
similar studies shown, and how your project will address the
scientific questions.
4. Data and Analysis: ~ 2
pages of text, describing the details of the imaging data and how
you processed the raw images into the final product.
5. Results: ~ 2-3 pages
of text describing quantitative results of the data analysis.
Specific things you should describe here:
- Your final B image of M101.
- Surface brightness profile for M101, along with a fit to an
exponential disk model. Decide how best to fit the surface
brightness profile, and describe your reasoning.
- B-V color profile for M101
- Derived properties of M101's disk, all determined from your
fit to the surface brightness profile:
- exponential scale length (expressed both in arcminutes and
in kiloparsecs),
- the approximate radius of the 25th mag/arcsec^2 isophote
(called R25) in both arcmin and kpc,
- the disk central surface brightness (in B mag/arcsec^2),
- the total brightness of the galaxy (in apparent and
absolute V magnitude, and also in solar luminosities).
- Give quantitative error estimates on your parameters
(derived scale length, central surface brightness, and total
magnitudes). Use the uncertainties in your fit to calculate
uncertainties on the parameters.
- Give qualitative discussion of uncertainty -- any
systematic or random uncertainty (not included above) that you
think may be affecting your results.
- Comparison of your results to previously published
measurements for M101 (you should compare to at least two
different previous works).
6. Discussion: ~ 2 pages
of text discussing the implications of your results. In
particular, what do the morphology, surface brightness profile,
and color profile tell you about the stellar populations in M101
and the galaxy's evolution history? Think about things like the
star forming history of the galaxy, the environment of the galaxy,
how it compares to other spiral galaxies (either individual spiral
galaxies or spiral galaxy populations in general).
7. Conclusion/Summary: ~ 0.5 page of text, summarizing
your results and conclusions.
8. References: A listing
(ApJ style) of references you've cited in your paper. You should
have ~ 12-15 references from refereed scientific journals or
monographs (not textbooks, educational websites, or popular
magazines).
Analysis Code:
You should also upload your jupyter notebook in which
you've constructed the surface brightness profile, and done the
fits and calculations. This should be completely separate from
your writeup, and there should be no code in your actual
paper.
Notes and suggestions:
- Counting up the suggested page lengths for each section, your
total paper should be about 8-10 single spaced pages, not
including figures or references.
- Equations should be used very minimally, if at
all. For example, we all know what an exponential profile is,
you dont need to take up space typesetting the equation.
- Figures in the body of the text are fine, but the page counts
above refer to the amount of text. You can also put your figures
at the end if you prefer. And remember, figures always need
figure captions to explain them!
- You should cite ApJ style. That means that when you refer to
someone else's work in your paper, you cite it in the text as
"(Dewey et al 2010)" and then list it in the references as
"Dewey, C., Cheatem, A., and Howe, J., ApJ, 454, 12 (2010)". In
the reference list, that first number is the journal volume, and
the second number is page number (for older papers) or paper
number (for newer ones).
- Astrophysical Journal format refers to overall structure, not
specific typesetting layout. You do not have to
use LaTeX or the astrophysical journal LaTeX templates.
- Spelling, punctuation, and grammar all count. Spellcheck and
proofread your paper! Revise as necessary.
Research Starting Points: