The Barney

"Nothing, and Everything, is Possimpible"

- Barney Stinson

Last updated: 11/20/2020


RSG+B Star Binaries: Binary Fraction

Using MagE and Hectospec data of M31, M33 and the MCs, determine the ratio of binary to single RSGs. We already have a pretty good handle on the number of single RSGs, so at this point it is just determining the number of binaries.

Status: working on M31 and M33. Since I'm getting a bunch of Gemini data and should also get the RSG+Be stars in the LMC, I should write another paper talking about those and comparing my results to that of Dorda's radial velocities ... (see RSG+Be stars below ...) All Gemini data has been obtained!

RSG/WR Ratio

Determining the ratio of RSGs to WRs in the Local Group Galaxies should provide an exacting test of evolutionary theory (for both single and binary star models). Using color-color cuts, UKIRT data, the LGGS, etc., and filtering the results through Gaia, we believe we have a strong list of RSGs and WRs.

This has been passed off to Phil. I'll help, but he's taking the lead

RSG+B Star Binaries: RSG+Be stars

We've found 8 RSG+Be binaries in the LMC/SMC. None have TESS, most have ASAS-SN but don't show anything too extraordinary, all Be stars *seem* to be dwarfs, and none are B[e]. Let's keep this in mind, but put it on hold for now. Maybe we can get some more spectra of these stars in the future?

RSG+B Star Binaries: Variability

The variability of single RSGs has been well studied in most of the Local Group Galaxies, but nothing has been done for the binary RSGs (since they aren't really known yet). Use ASAS-SN and PTF and other things to investigate the variability of binary RSGs.

Status: Have a bunch of PTF / ZTF data. Could also use ASAS-SN. Wrote a program in /research/variability/calcLC to determine the basic calculation of whether we could detect a binary. But, it might be wrong for the time of eclipse. I'm getting like 0.5 days when it should be on the order of years ... so, yeah, need to test this with VV Cep and other famous ones to see if stuff matches up.

Need to do this by: not time pressing, probably something short in my thesis and maybe a paper in the future.

RSG binaries in the UV

HST proposal declined, resubmit in 2021

OB stars in M31 and M33

Use PHAT/PHATTER? At the UV wavelenghts you might be able to do something ...

Merged RSG Binaries: I can't believe I ate the whole thing

Merged RSGs should have different spectral and physical properties than non-merged RSGs. Their abundances should be different, their rotational velocities should be higher and their mass loss rates should be ... different. Using high-resolution echelle spectra, try and search for the differences.

Status: currently getting LDT data. Waiting on VLT. Data obtained in Fall 2020, write-up in Spring 2021.

Maria YSG: Are they coming or going?

YSGs can either evolve to the red or back to the blue. Depending on whether they've gone through the RSG stage or not the should have different abundances and rotational velocities. Using high-resolution MIKE spectra of 100 YSGs in the LMC, identify which way they're evolving. (also, variability)

Status: Maybe I should email Maria at some point ...

M31/M33 WR/O bin masses

Using photometry to obtain lightcurves and spectra to obtain radial velocities, we should be able to directly measure the masses of a few WR+O star binary systems.

Status: Things are currently not going so well ... we weren't able to find any good systems with light curves and wilson diagrams. More DCT data happened ... needs to be reduced.

After that ... See if any of them look better. If they do, write up a paper. If not, cry.

WN3/O3s in M33

We found WN3/O3s in the LMC ... where are they in other galaxies? Maybe they are only found at some metallicites. Since M33 has a strong metallicity gradient, we want to see if a) we can find them and then b) if they only appear at one metallicity.

Status: Band II for Gemini ...

Gemini IC10

We observed candidate WRs in IC10 using Gemini a few years ago. Let's see if they're real!

Status: Reduce data! Well, Phil needs to do this.


We have good lightcurves and spectra of BAT99-77. We should be able to derive the physical masses of the two components.

Status: Basically passed off to Tomer.


Same as above for BAT99-77. Single lined binary.

Status: Some lines have been measured, but I don't think anything was ever sent to Laura Penny. Maybe this is a good summer student project? But no rush.

Of stars vs. Stripped WRs

The spectra of Of stars has weaker HeII 4686 emission like that of a weak-lined WR. But what if it also has strange hydrogen abundances? Maybe we could look at all of the Of star spectra we've accrewed and do some sort of modeling?

Status: Need to put together a list of Of star spectra. I think Tomer and maybe Emily are also interested in this project. Note: Phil thinks this is crazy he thinks it might be interesting to determine M_vs for the stars using gaia and then compare the M_vs to their 4686 emission. Maybe there will be some strange ones ...