Alessandro Sozetti chairs the day's final session, on "The Small Star Opportunity."
Says "If you are a current or former student of Dave Latham, please raise your hands." A very good showing. "If you are a long or short term collaborator, raise your hands" (most of the room has their hands up now).
"The few who have not raised hands, please pay your registration fee."
Now, the first speaker is (close AstroWright friend) John Johnson.
He says that his experiences with Dave, mostly after having given a talk, is that Dave has been "extraordinarily kind to other scientist" Dave looks incredulous until John continues "...especially to younger scientists. I've seen him be cranky with older scientists." Thanks Dave for that and says being kind to younger scientists really sets a good tone for science. This gets applause.
Problem: it's difficult to characterize M dwarfs. John is describing the work of several Jamie Lloyd students and postdocs, Barbara Rojas-Ayala, Phil Muirhead, and Kevin Covey. This gives radii of the M dwarfs, lets us get good radii for the planets.
KOI 961 is a near twin of Barnard's Star, which is very well characterized, which really helped. The KOI 961 triple system has all 3 planets smaller than the Earth, and the best figure "for scale" is not 51 Peg, but Jupiter and the Galilean Satellites.
"I love that I can say that and nobody gasps. It's just 'yeah, we've seen that.' What a great era this is."
Two undergraduate students found a strange M dwarf transit around KOI 256 -- the flat bottomed, very sharp ingress/egress. RV work at Palomar revealed that the "transit" was at the wrong phase, is actually the secondary eclipse. The true transit is at the wrong depth because of lensing effects. Kepler does general relativity!
Next up, John Swift's work on Kepler-32, a 5 planet system with the innermost planet in a 0.01 AU, 0.7 day orbit, and the next two out participate in a 3:2:1 period commensurability. Might be very typical of M dwarf systems, which dominate planets in the Galaxy.
Next, Morton & Swift's work on a period-normalized non-parametric radius function with a modified kernel density estimator. Most common size planet around M dwarfs so far: 1 Earth radius. Statistically significant bump near 2.2 Earth radius, maybe. See a real deficit in distribution at less than 1 Earth radius. Shows that MEarth will have great success with just a bit more precision (distribution falls off above 3 Earth radii = GJ 1214).
Cites Dressing's work that there are 0.15 Habitable Zone planets per star. Nearest Earth-size planet in the HZ is 21 pc away.
Next up Suvrath Mahadevan about the "challenges and opportunities" of near infrared precise radial velocities ("another tool in our toolbox in finding planets around M stars").
Starts with a detour about APOGEE: 300 fibers on the Sloan telescope doing H band velocities.
At one point, the APOGEE team said "we think we've found a planet" and sent him an RV curve that got sent to him; APOGEE was very excited because they saw a 80-day period signal around a 7th magnitude star. This sounded very familiar. [At this point Dave Latham is looking at the 2MASS ID, which has the coordinates, and says "hey, wait a minute" and the audience starts to catch on]. Suvrath* looked the star up in the literature, and it turned out to be HD 114762! They were using this as a telluric standard, and the RV pipeline had seen variation. This is the first NIR exoplanet detection! Suvrath declares that NIR can now clearly detect exoplanets.
NIR information content isn't as high as optical, but more flux means you win in Z, Y, J. Habitable Zone Planet Finder (HPF) has R~50,000, with requirement of < 3 m/s precision and goal of 1 m/s on best stars. Heritage comes from Larry Ramsey's Pathfinder tested at Hobby-Eberly Telescope. Pathfinder retired a lot of risk and concern about NIR spectrographs, including detector issues (persistence, inter-pixel capacitance) and calibration sources.
Shows actual on-sky laser fiber comb velocities, showing stability of carbon dioxide telluric lines (only stable to 5-10 m/s) and stars. Also shows Fabry-Pérot interferometer comb tested at APOGEE, which looks great.
Hand agitation of fibers seems to reduce modal noise, but this is "not practical for a five-year survey." Commercial device solves the problem: "OptoTune laser speckle remover" which does exactly what it sounds like, and combines with an integrating sphere to solve modal noise of bright calibration sources.
Octagonal fibers + double scramblers give sufficient scrambling to get sub-m/s precision.
Last speaker is Jonathan Irwin, talking about MEarth. We would like to be able to do the sorts of science we do on GJ 1214 to Earth-sized HZ planets. This makes mid- to late M dwarfs the most important targets.
MEarth has been running since 2008, original survey sensitive to 2 Earth radii.
The original MEarth building was Cold War era laser ranging station. It is bomb-proof, roof has never failed. Also housed Fairborn Observatory before MEarth.
High proper motion of M dwarfs very useful, and MEarth data can generate parallaxes. MEarth also
People are always asking "has MEarth found another planet?" Says answer is "no, and we'd like to understand why." To do this "I have to do something naughty" -- he is extrapolating from early M's in Kepler to the late M's from MEarth. GJ 1214 looks like an oddball if you do this extrapolation, but if you compare by equilibrium temperature it's not too bad. Kepler shows the planet frequencies goes up in the same dimensions that MEarth's sensitivities go down, so a bit more precision will yield a lot of new planets.
MEarth South is coming along soon!
That's a wrap for day 1. Hopefully blogging will commence for tomorrow's session, but perhaps not by me.
[* Update: Suvrath points out that it was David Nidever and Scott Fleming were the ones that made the identification. The full story is here.]