This is not a blog post as such, it’s the notes that I took during the conference split up into sections. Unfortunately there is no reference to the talk content itself; this is kept in the booklet which I have sitting next to me as I type this.

Session 1

Detecting and characterising via direct imaging

• More than 2Gyr gas giants more than 10⁸ times fainter than primary
• Young stars are 10⁴ – 10⁷ times better than this
• Chronograph for increasing contrast
• Speckle noise a big problem
  • for speckle based data S/N does not increase with time
  • angular differential imaging
    • speckles oscillate while image rotates, but keep similar shape
    • real objects will move in the frame
• A stars good targets despite being bright
  • higher hosting fraction for giant planets for A stars (not sure about this)
  • high profile detections
  • Nielsen show low host fraction despite this
• M stars also good targets
  • despite low independent host fraction
• Typical contrasts – 10⁵ at 1 arcsecond (with NICI)

Physical properties (atmospheres)

• Direct photons detected from these objects
  • reflected light and background contaminants surely?
• Colours in infra-red shows deviations from the predicted T dwarf type sequence (brightness vs colour)
  • more like L dwarfs
  • much lower surface gravity
• Direct spectra taken (!)
• Huge spectral diversity for planets even in same system
• Surface gravity strongly affecting the spectra
• Orbits of Beta Pic 2 – Chauvin et al. 2012
  • most probable semi major axis

Architecture

• Upper limits to abundance
• Cold start – less than 10% for separations 20 – 630 AU
• Hot start – less than 10% for separations 10 – 810 AU
• Gravitational instability planets rare at more than 10 AU
• Scattering planets also rare
• Sphere project – 10 – 80 more planets
• Possible detection of Super-Earth around nearby M dwarf (Crossfield, Goyon et al. 2013)

Summary

• Young exoplanets have red colours consistent with dusty clouds and non-equilibrium chemistry
• Hot start gas giant planets more than 4 MJup rare at more than 10AU

International deep planet survey

• Homogeneous analysis methods

SEEDS

• Strategic Explorations of Exoplanets and discs with Subaru
• Variety in morphology of protoplanetary discs
  • gaps, non-uniform shapes
• IRD – IR doppler instrument on Subaru
  • could be good for follow up for NGTS, investigate this
  • paper

Hershell dust evolution in discs

• SED modelling and Herschel tracing dust evolution in discs

Planet formation in evolving protoplanetary discs

• Gas dominates planetary formation
• Planets form in evolving discs
• Disc dispersal quick and efficient
  • relatively few systems found with partial discs
• Accretion in disc core, with photoevaporation at higher disc heights
• Changes in disc structure can form traps for dust or planets
• Final gas disc dispersal halts planet migration
• Giant planet migration can be halted if the disc gas is dispersed
• RDA & Armitage 2009, RDA and Pascucci 2012
• Pile up observed in models and data at 1-2AU
  • looks like a possible pile up at smaller separations also

Disc inhomogeneities and the origins of planetary system architectures and observational properties

• Discs have 3 types of planet trap

HST/STIS imaging of Fomaulhaut: New main belt structure and confirmation of Fomalhaut b’s eccentric orbit

• Highly eccentric 0.8
• A ~= 1.77
• Periastron: 32AU
• P ~= 1700 years
• Dynamically linked with belt
  • mutual inclination (planet – belt) ~ 17 degrees
  • Periastron linked
• Gap in main belt of ~50AU
• Inner belt detected
• Planet planet scattering: Chatterjee et al. 2008

Highlights of Exoplanet Characterization

• Planets are diverse in Teff(planet) vs IR colour, no clear pattern yet
• Uranus and Neptune heavily enriched in carbon (50x)
  • also very old, about 50K
• Consistent non-detection of CO in GJ436
• Featureless atmosphere of GJ1214b suggests high mean molecular weight
  • dramatic cloud obscuration
  • high water constituent
• Low mass planets may have high Zenv (metal fraction of the envelope)
• GJ3470b – Uranus analogue
• GJ436b has dayside and transit data breaking atmospheric degeneracy
• Comparisons of C/O ratio for star and planet v. interesting

Planets around low mass stars (PALMS) high contrast imaging survey

• Link with microlensing
• Snapshot program – breadth not width
• Gravity-dependant L to T dwarf transition

Session 2

Review

• Radio maps more than 95% of mass
  • good for structure

Triggered planet formation in action: resolved gas and dust images of a transitional disk and its activity

• Surface density excess after a planetary body traps large dust particles in a potential maximum
• Increased density leads to planet formation

Session 3

Review – The story of planets: anchoring numerics to reality

• Hubble protoplanetary disk atlas – nice pictures
• Disc gaps depend on grain size – different wavelengths probe grain size and gap width
• Grain growth drives planetessimal (~km sized) formation
  • not reliable
• Pairwise accretion – slow, turbulence high, has issues
  • requires velocity dispersion/distribution in simulations
    • mean velocity is not enough for an accurate simulation
  • requires grain size distribution
• Pressure bumps trap dust
  • leads to further processes, gravitational instability, accretion
• Accretion very low fraction of simulated collisions
• Dust distribution dependant on planetessimal eccentricity

Zooming in on protoplanetary discs

• Magnetic fields in star forming region does not create planar disc initially
  • vertical structure is created
• Free-fall accretion guided by magnetic field

Planetessimal formation

• Disc cross section
  • core stable
  • edges suffer instability
• Planet trend with instability
  • mostly requires local Disk metalicity, could be super-solar

Session 5

A decade and a half of AngloAustralian Planet Searching

• 240 stars sample over 15 years
• 2.5 meters per second precision
• HD 20782 – highest eccentricity 0.952
• Wittenmyer et al., 2011, apj – reference for false rv signal testing
• R ~ 60000 – S/N needs to be 5000
• FunnelWeb – spectra of all stars V less than 12, delta less than 20, 390-800nm Very nice talk

The Debiased Kuiper Belt: Our Solar System as a Debris disc

• 20% large KBOs more than 100km are in resonance with Neptune

Planets and Stellar Activity: Hide and Seek in the CoRoT-7 system

• Active granulation effects for RV
  • bright blue cells dominate cool red cells = net blueshift
  • creates RV signal of ~ 1m/s
• Use lightcurve without transits to provide activity profile
  • simultaneous observations
  • RV profile then contains both stellar noise and planet
  • use lightcurve as basis function

Properties of the young gas giant planet Beta Pictoris b

• Planet on inclined orbit around star, inclined wrt disc

Characterizing the Demographics of Exoplanet Bulk Compositions

• New kepler mass radius relations with Keck

Unveiling an exoplanetary Neptunian atmosphere through multiband transit photometry

• Infra-red used to measure bands H2O, CO, CH4

The Shocking Variability of Exoplanet Transits

• WASP-12 b bow shock in the infra-red

Session 6

Debris discs as components of extrasolar planetary systems

• Debris disc descendant of protoplanetary disc
• Proplyds
  • less than 10MYr
  • optically thick
  • more than 10 Mearth
  • ~100x dust mass
  • dust from 0.1-100AU
  • primordial?

• Debris

  • 10MYr -10Gyr
  • optically thin
  • less than 1 MEarth
  • no gas
  • ~30AU ring

• Inner holes caused by planets?

• Inner edge of disc predicted to be carved by planets
  • shape of the edge depicted by planet mass
• CO short lifetime ~100 years due to photo-disassociation
• Clump in disc
  • could be through planet orbit and gravitaitonal influence
  • could be a destruction event causing debris to pass through the same point leading to higher density
• Alma probes mm sized dust – traces planetessimals
• Scattered light probes micron sized dust
• Systems with planets are brighter (SKARPS, Herschel) than systems without implying debris discs

A Resolved Millimeter Emission Belt in the AU Mic Debris disc

• Best fit model suggests increasing surface density with radial distance
  • inner collision depletion?

Detailed model of the exozodiacal disc of Fomalhaut and its origin

Final Results of the Herschel Open Time Key Programme DUNES

• 16 resolved discs, 13 new

Session 7

Review

• Morbidelli+ 2009, planetessimal simulation
• Rafikov 2004, proposed explanation of accelerated core accretion
  • neptune in less than 10Myr

Rapid growth of giant planet cores by pebble accretion

• Pebble accretion can rapidly grow the planet mass and deal with collapse, according to the model
• Author: Lambrechts

Planet Formation and Evolution in Traps: Origins of the MassPeriod Relation

• Traps catch planets while forming
• Rapid envelope accretion process
• Model predicts that super earths are failed jovian cores
• Putdritz model looks interesting
  • predictions for hot Jupiter formation
• Giant planets start at greater than 0.7Msolar

Session 8 – evolution of planetary systems

Review

• Interesting deficit of period ratios in Kepler dataset just below 2:1
• Resonances cause oscillations of the periastron points of a multiple system
  • non-resonances cause circulation
• If the system is not stable with aligned systems (angle of periastrons equal) then all other configurations will be unstable
• No close encounter required
• Hill radius associated with circular orbits
• Dissipation acts to stabilise systems
• HAT-P-13 is multiple planet system
  • why does WASP not find any?
  • consider changing wasp pipeline to subtract the in-transit data and re-perform search N times
• MMR Lithwick
• Could the Kepler distance from pure resonances be due to unseen non-transiting bodies?

Constraining planetary migration mechanisms in systems of giant planets

• Dawson and Johnson 2012 – predicting eccentricity from Kepler lightcurves
• Metal-poor and metal-rich lead to disk migration
  • only metal rich stars form multiple systems
• Fressin et al. 2013 – kepler occurrence rates
• Possible pile up at short periods for metal rich Kepler host stars
• How do eccentric planets in the period valley between 0.1 and 1 AU form?
• Planet planet scattering possibly ejecting outer planet removing it from evidence for it

The Impact of Stellar Multiplicity on Planetary Systems

• High protoplanetary disc occurrence for wide binary planets
  • distinct decrease below binary star separations of ~40AU
• Similarly decreasing disc mass with decreasing orbital separation
• RV surveys biased against binary stars due to the stray light from the binary companion in the slit
• Only equal flux binaries at short separations
  • selection effect?
    • maybe planets form around the fainter secondary and are therefore harder to detect so we don’t find them

Orbital structure of Kepler Planetary Systems

• Low mass planets targeted for the talk
  • less than ~30Mearth
• Fortney 07 density structures
• Bimodal small radius distribution
  • can be split by the x-ray exposure
• TTV mass estimations extremely sensitive to eccentricity

Archaeology of Exo-Terrestrial Planetary Systems

• RECONS project – spectral types within 10pc

I’m currently on the plane back, flying over Canada at about 922km/h as the in-flight computer (android tablet in the back of the seat in front of me) says.

I’m sitting next to a nice chinese couple, who don’t speak a word of English. They asked me through vague hand gestures to fill out their immigration card. It was quite an ordeal!

Back home now after a good conference, got lots of nice pictures of Vancouver, but am quite tired now.

The last day has come and gone. I didn’t get time yesterday to write about it so I’m doing it now while I sit in front of the A-team in a Canadian hostel. As a side note this film looks terrible.

We had some of the most interesting talks of the day yesterday, talking about planet migration and feasibility studies. Some cool stuff but I still don’t have a disc migration based theory to explain the Rossiter-McLaughlin effect. A quite sensible talk was about the formation of hot Jupiters and how the primary migration mechanism is based on the host star (or disc) metalicity. Low metalicity stars can only cause hot Jupiters to migrate through type II migration due to lack of metals from which extra planets can be formed. High metalicity stars can support the same process, as well as dynamical formation as more planets will have formed from the protoplanetary disc. It kinda makes sense in my mind.

After the conference I met a nice Chinese man on the bus to the ferry and we traveled together until I got to my stop on the sky line. He was in educational research and worked in Ottawa, and we had a nice trip.

I got into my hostel and went to get some dinner. I went back to the same place Dave, John and I went on the last night as I knew it’d be good, and I could sit somewhere and pass the time. I ended up eating at the bar and sat next to a couple who ended up introducing themselves to me and we spent the rest of the night drinking and talking. It was a lot of fun!

I’m currently drinking my coffee, and getting ready to go out and explore Vancouver. The weather has finally turned and it looks pretty cloudy outside, but I’m English so my shorts and sandals are making a guest appearance one last time. Soon I’ll be back in England a day later than I left and probably not going to be very communicative.

Today’s lectures were about… you guessed it: discs! A lot of people find them interesting apparently! Anyway the talks were ok, some good some bad. One in particular involved formation theories that seemed to explain the observed distributions well; I wanted to ask about selection effects but thought I’d find him afterwards. I didn’t have time in the end but it was very interesting.

Coffee was taken up by talking to a postdoc at UNSW about dynamical stability. We chatted for a while and it was nice. Lunch was an amazing experience: we heard about a great fish and chips place down by the harbour. It was not more than a shack and we were warned of the queues. We thought nothing of it and with a 2 hour lunch break had plenty of time. So we went down and queued for a while. A while being 1 hour 15 minutes. In the sun. I don’t get sunburnt very much but my face is quite red right now! By the time we’d finished eating it was time to return to the conference centre and resume the day. IT was fantastic food though, I’d recommend it if you’re visiting and have a couple of hours over lunch to space.

After the sessions were over we went to the conference banquet at the Victoria museum. A very nice place, with interesting exhibits about the local history of Canada. There was a nice timeline explaining some key events in Canada’s, and Victoria’s past. The food was a buffet style affair with tables set with sushi, dumplings, meats on skewers and fish. Quite a selection, though we had one free drink each and the subsequent were quite expensive! I talked to a nice guy about his research and how one could go about observing it. A quite unusual idea for a conference banquet, not quite the formal dinner around tables that we’d expected.

So we come to the downside of the day: the price of the banquet. $90 Canadian for the dinner. Yeah.

Today’s schedule was short, we had the afternoon off to do whatever we wished. Actually the conference organisers offered to put on a trip of some sort after a vote to find out the most popular choice, but that fell through as organising such a mammoth activity would be too difficult.

This session was the most relevant to me and my work, as it involved the observational side of things. We had some great talks from some friends of mine, and other colleagues in the field.

A very interesting talk was given about statistically ascertaining the point at which planets become gassy, through probabilities. Another was about bow shocks around giant planets, and another was a method to use simultaneous RV and transit methods to reduce stellar noise effects.

But the crowning glory of today was the afternoon bike ride and subsequent dinner/pub. We cycled around 30km int he end (about 19 miles in old money) around the south of Vancouver island. Very nice scenery. We had tapas for dinner, followed by a nice pub trip;.

A good day in all

So today we learnt about discs, as the title of this post may suggest. We had protoplanetary discs (or proplyds which is a horrible portmanteau), thin discs, thick discs, transitional discs…

This mostly involved theorists and simulations working their hardest, but we did get a few observational results thrown in for good measure. To be fair it’s a simulation type topic, current methods are not powerful enough without some serious and therefore expensive time on the largest telescopes. Some nice analysis advances are being made but for once¹ observationalists have to play catch up.

We finished with a public talk from Debra Fischer and a slightly US-centred view on the history of exoplanet discovery. There was one nice picture of Mayor and Queloz by the telescope. A good day in all.

So the first day has just finished. We had some interesting talks (and some not so interesting, but that’s to be expected).

The first session – before lunch – was dedicated to direct imaging, which is really taking off as a field, with advancements in technology and analysis tools since I last updated myself on the field. Being able to directly see protoplanetary disks is a new idea for me.

The idea I liked the most was a clever way to detect a secondary body around the star. The complex optics and stellar flux removal techniques leave a noise characteristic pattern around where the star once was. This changes from frame to frame but fundamentally does not really change shape. A moving planet however does change position. The “speckle” pattern does not care about the orientation of the ccd so the field of view rotating will appear the same. By observing whilst the field rotates and then stacking the frames aligning them by the orientation of the frames provides a clear target which stands out from the background.

After lunch was a session on disks, with lots of hydrodynamical simulations and the like. All quite complex, but some ground-breaking results. An observation of an almost completely asymmetrical disk with a proposed explanation. This doesn’t sound particularly exciting when I write this but it was quite cool. IF my memory was better I’d write it up a little better.

Anyway about to go to sleep now, another busy day tomorrow with a public talk given by Debra Fischer, most likely announcing new results from Kepler which could be interesting given its current state.

The ferry from Vancouver to Vancouver island (not Victoria island, as I’ve been told) was amazing. The scenery was breathtaking, photos of which I shall upload later. The little islands around Vancouver island were amazing to see, really fantastic. The map is centred on Victoria itself but the islands are to the north east.

We’re sitting on a coach waiting to depart to Victoria town centre, ready to find our hotel and work out where the conference centre is.

So we arrived at the hostel, a very nice place too. I’d recommend it if I could be bothered to find out what it is. I’ll try and remember to insert a reference here:

Reference

So yeah nice place. Vancouver is not very exciting so far but as was pointed out to me: the area around the airport is never going to be very nice.

The public transport on the other hand seems excellent so far. I’ll not get much of a chance to test it out, but from what I’ve seen so far it’s excellent. Fantastic public transport to and from the airport, something London sorely needs.

The city itself looks pretty good too, some fancy shops with names I’ve never heard of, and Claire’s accessories of course. That infects every city it touches these days, but that’s another topic for another day.

We’re just about to go get some food and some drinks. I’ve been up since 6am which makes the writing of this post the 20th hour of being awake. It’s not really hitting me yet, but I’m sure I’ll sleep well tonight!

More astronomy to follow, probably.

So we’re at the airport. Mostly uneventful journey so far, luckily. Airports terrify me; flying doesn’t scare me at all, but the chance of being rejected for something as simple as forgetting your passport is so unnerving.

I’ve been up since 6am this morning, which is pretty tough. I’ve managed to get some free wifi at the airport, ironically from BT Openzone which have announced that they’re closing to O2 customers. This is ironic for two reasons:

1. As an O2 customer I was not aware of this ability before today (ok this is not technically irony)
2. I’m checking the internet through BT OpenZone as we speak!

In other news, much more sad this time, a co-founder of the fantastic Oculus Rift was announced to be the pedestrian who was killed recently in a police chace. I’m not sure how this will affect the company, or the development of the rift as a whole; I’ve not been following development but I’ve heard some good things about it from many sources.

About to board the plane soon, then the long flight where my laptop battery will be tested to its limits. Another post soon, providing I can get some time. So much learning to be done.