F. Millour O. Chesneau, D. P. K. Banerjee, E. Lagadec, C. Lykou, A. Meilland, N. Nardetto, M. Otulaskova, A. Spang Cannes Esterel  Monaco My workplace Nice Nice airport Antibes Mediterranean see

15/11/2013F. Millour, HTWUIII, Santa Fe 2

15/11/2013F. Millour, HTWUIII, Santa Fe 3 Binary UD + point UD Gaussian D

15/11/2013F. Millour, HTWUIII, Santa Fe 4 Binary UD + point UD Gaussian B1B1

15/11/2013F. Millour, HTWUIII, Santa Fe 5 Binary UD + point UD Gaussian B2B2

15/11/2013F. Millour, HTWUIII, Santa Fe 6 Binary UD + point UD Gaussian B3B3

15/11/2013F. Millour, HTWUIII, Santa Fe 7 Binary UD + point UD Gaussian VLTI arrayVLT (NACO) 34 mas Binary HD87643

NPOI array CHARA array 8

9 Chesneau, et al. 2008, Das, et al Chesneau et al One of the historically slowest nova observed Reached V~3.8, Monitored during 5 months by the VLTI and Mt Abu ( 1-2 and 8-13 micron observations) Sparse uv coverage (1-3 bases at a time): slow process, assuming spherical symmetry use of the DUSTY code for the interpretation. JHK light curve 15/11/2013F. Millour, HTWUIII, Santa Fe

Follow-up nova expansion from 23 days up to 5 months after outburst, Model suggests an accumulation of M ʘ of dust Expansion of 0.35 mas per day. Indications that the source is not spherical 15/11/2013F. Millour, HTWUIII, Santa Fe 10

2009, 2010, NACO , VISIR High inclination bipolar nebula No equatorial structures in IR, VLTI expansion measurements in line with major axis expansion, D>1kpc (Sadakane et al. 2009, Naito et al. 2012) A slow nova can ALSO create a striking bipolar nebula: common envelop effect? Perfect (bright) ALMA target Should now be a 1”x0.6” nebula But need continuous monitoring! 15/11/2013F. Millour, HTWUIII, Santa Fe 11

Discovered by H. Leavitt in 1913, ‘Recurrent’ nova, oubursts in … ? … 2011! Nebula deeply studied by the HST (Shara et al. 1997), ‘Slow motions’ measured (v~600km/s, Schaefer et al. 2010) Binary spectrocopic signal resolved, q=0.2, i~10 (Utas et al. 2010) 15/11/2013F. Millour, HTWUIII, Santa Fe 12

Chesneau, Meilland, Banerjee et al T Pyx outburst combined CHARA and VLTI observations Results Slow expansion (v 3.5 kpc) The source appears circular (r=1+/-0.07), Extended complex phase signal in the Br  line, thanks to: A. Meilland, G. Schaefer, S. Ridgway, T. ten Brummelaar, A. Merand, J. B. Le Bouquin, M. Wittkowski… 15/11/2013F. Millour, HTWUIII, Santa Fe 13

Are these ejecta spherically distributed? No, probably concentrated near the equatorial plane facing us. This should be checked with a careful polarization study of the clumps (see the recent controversy on RS Pup, Kervella et al.; Bond et al.) t=35d Face-on bipolar nebula! PA angle 110° well constrained Inclination not well constrained 14

15/11/2013F. Millour, HTWUIII, Santa Fe 15 Radio 40 mas 65 AU t = 22 days HST Visible 240 mas 380 AU t = 150 days Time VLTI IR 9 mas 15 AU t = 5 days O’Brien et al. 2006, Chesneau et al. 2007, Bode et al. 2008…

V1280 Sco: Chesneau et al. 2008, Chesneau et al T Pyx: a face-on bipolar nebula Chesneau et al., 2011 t=150 d RS Oph: O’Brien et al. 2006, Chesneau et al. 2007, Bode et al. 2008… t=5d t=35d V445 Pup: Woudt et al t=900 d 15/11/2013F. Millour, HTWUIII, Santa Fe 16

Why bipolarity? 1.Channeling of the outburst by dense circumbinary material? Perhaps for V445 Pup, Circumbinary density enough in the case of RS Oph? Probably not applicable for V1280 Sco, and not for T Pyx, We need to evaluate carefully the mass around many recurrent/classical novae 2.Common envelop interaction? Favors slow nova, since time scale is short, and effects might be limited Difficult to observe the effect of the companion during this phase 3.Transient jets? Would explain velocities observed and collimation, 4.Intrinsically massive ejection? Spun-up WD, rotating a P<1min  what effect on detonation/explosion? Channeling through strong magnetic field, that should be detectable And then??? Binary systems! 17

Chesneau, Clayton, Lykou et al The born-again Sakurai’s object 10 years after the outburst (1996) a disk is found in the core of the old PN (Chesneau et al. 2007) The PA. of the equatorial overdensities coincides with the old PN symmetrical axis 8 micron 10 micron 13 micron The born-again phenomenon in the frame of the evolution (Lai, De Marco et al. 2010) : -a VLTP? But the 2D aspect must be taken into account! 1D models to date… -a merger? The O16/O18 ratio is normal contrary to R CrBs (Clayton et al. 2010)… 18

The outburst of V838 Mon The prototype of ILOT The near-IR and mid-IR flux of V838 Mon remains high enough for VLTI observations. Two hypotheses that can be tested in the near/mid-IR (AMBER/MIDI) -The mid-IR flux is dominated by a late M supergiant, -The mid-IR is dominated by an expanding dusty wind, -The mid-IR source is dominated by a forming disk, whose characteristics such as the inclination, may be measured In the near-IR, we may be able to follow and measure the angular size of the supergiant. Do we expect an emerging fast rotating source when the source may eventually get smaller and hotter? Other question: - Is there an expanding bipolar nebula around? MIDI/VLTI observations ( ) 19

20 T Pyx A. Merand 15/11/2013F. Millour, HTWUIII, Santa Fe