Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 03/06/2017 - 19:34
Does anyone know of published research that analyzes planet and planetary system characteristics vs. stellar age and/or stellar spectral class of the host star? I am particularly interested in finding any analysis with regard to stellar spectral class.
Brad Walter, WBY
Like this?
https://arxiv.org/pdf/1405.3728.pdf
Blake
Or this?
http://iopscience.iop.org/article/10.3847/0004-637X/818/1/87/pdf
Blake, Thanks for these papers. I had not seen them before. Like the other papers I have found these provide individual data points that would be input data to the paper I am hoping to find which would be a much more global statistical analysis of distribution of planet and planetary system characteristics across spectral classes and/or stellar ages. Extrasolar planet encyclopedia has some plotting capabilities to do scatter plots comparing two numerical variables associated with planets and planetary systems such as comparing planet mass to stellar age or semi major axis to stellar age. It just seems to me that someone must doing research looking I know there is a stron bia
for correlations among stellar characteristics and planet/planetary system characteristics across the known population of exoplanets.
Brad Walter
I suspect you would be much more likely to find research using host star mass as the variable of choice, rather than spectral type. Spectral type is very rarely used as a variable in research for "normal" stars these days, even if some plots do still label their axes using it.
As for stellar age, this is a difficult one, simply due to how uncertain most stellar ages are! Also, I imagine that age would act as a proxy for other properties of the star, e.g. its composition, which should include more metals for stars born more recently.
When considering mass/metallicity correlation, the number of papers is much higher! Perhaps a good starting place is the Winn & Fabrycky 2014 review article, which is widely recommended as a good review of all things planet-related, although a couple years old now. The entirety of Chapter 2 is devoted to planet occurence rates: https://arxiv.org/abs/1410.4199
Johnson et al. 2010 claimed trends for giant planet occurence with both metallicity and mass (https://arxiv.org/abs/1005.3084). The metallicity trend is well accepted, but the trend with stellar mass has been debated and regularly bounces between "nonexistent" and "significant". For example, Mortier et al. 2013 did not find strong evidence for giant planet occurence rate being dependent on stellar mass (https://arxiv.org/abs/1302.1851), but I can easily find papers such as Jones et al. 2016 which do support a trend with mass (https://arxiv.org/abs/1603.03738).
Wang and Fischer 2013 found a metallicity trend for smaller planets as well, but this is much less strong than for giant planets (https://arxiv.org/abs/1310.7830), although the abstract of Wei et al. 2016 implies that this has since been debated and is difficult to determine due to the very high frequency of small planets (http://adsabs.harvard.edu/abs/2016ApJ...832..196Z).
In addition, recent surveys and studies appear to show that M dwarfs are almost entirely devoid of giant planets, with e.g. Gaidos et al. 2016 (https://arxiv.org/abs/1512.04437) finding that these stars host almost no planets greather than 4 Earth radii. Additionally, they also appear to be more likely to host small planets, e.g. Howard et al. 2012 (https://arxiv.org/abs/1103.2541).
For more papers, NASA's ADS system is really very helpful - for example, the Johnson et al. 2010 paper is listed here: http://adsabs.harvard.edu/abs/2010PASP..122..905J
By clicking on "Citations to this article" (link included below), the ADS will list every paper that has cited the Johnson et al. 2010 paper, which includes plenty of people arguing about its results! Any paper with a green "X" link is available freely on arXiv, which accounts for almost all of the journal papers (most of the exceptions are conference abstracts, books, etc.). Additionally, most arXiv pages include a link back to the corresponding NASA ADS page.
http://adsabs.harvard.edu/cgi-bin/nph-ref_query?bibcode=2010PASP..122…
Extremely helpful comments. The depth of knowledge makes me suspect that Danny252 Is Dr Daniel Evans, but in any case the input gives me a lot think about and work with. I plan to get back to observing exoplanets and EHB objects after I wind up my current CHOICE responsibility.
Thanks for the guidance and suggestions.
Brad Walter, WBY