Astronomy twitter journal club met for the first time in 2012 last week to discuss the recent discovery of a distant, dark, dwarf galaxy which may help explain the discrepancy between the predicted and observed number of Milky Way satellites.
The original paper can be found here, our preview is here, and the full transcript of the meeting is here.
The meeting was kindly hosted (at short notice, after a minor panic on my part) by Simon from @RHULPhysics. Onto the review…
Simulations
We don’t see enough satellite gals compared to sims. How significant is this paper? Anyone see any problems with it? – @RHULPhysics
doesn’t that mean that simulations are wrong? why is that wrong? Explain … #devils_advocate – @evanocathain
Yup, I would have always started by assuming sims weren’t right yet, which is why observing more sats is so cool, no? – @RHULPhysics
Gravitational lens model
Interesting paper. I wonder how model dependent it all is… – @KarenLMasters
Do you mean model-dependent in their lensing detection? – @RHULPhysics
yes. Detection is from fitting mass model to the Einstein ring, I don’t understand how much degeneracy in that. – @KarenLMasters
And finally
IIRC there’s quite a few lenses with anomalous image flux ratios suggestive of substructure. – @StephenSerjeant
If other lenses suggest substructure, is this a better detection, or just a braver claim? – @RHULPhysics
Better detection I’d say – @StephenSerjeant
Glad to hear it. Fingers crossed for more! – @RHULPhysics
