1. 黎卓 HB Perets, JC Lombardi Jr, SR Milcarek Jr JUNO会议，南京，2016/4/17-18
微型潮汐瓦解事件 (Micro-TDE) 黎卓
HB Perets, JC Lombardi Jr, SR Milcarek Jr
JUNO会议，南京，2016/4/17-18
Perets et al ApJ, arXiv:

2. Tidal disruption events

3. Observed TDEs
ROSAT
Swift: jetted TDE

4. What about TDEs by stellar mass compact objects?
Stellar mass COs
smaller by >> 106  micro-TDE
Radiation properties?
Timescale, energy, luminosity, event rate…

5. Fall-back time . Low mass-ratio TDE: planet
High mass-ratio partial TDE: star
Remnant object affects the dynamic of marginally bound debris
StarSmasher code: SPH . CO

6. BH: 10 Msun
Star: 1 Msun, ~ 1 Rsun
BH: 10 Msun
Planet: 10-3 Msun, ~ 0.1 Rsun
Decay faster: -7/3
Earlier: few ks
-5/3
Sub Ms

7. Partial disruption

8. Accretion time circularization of bound debris
disk/torus forms at rc=2Rp
accretion time
thick disk h~1
tmin~ a few 103 s

9. Light curve and energy
Light curve could be more relevant to mass accretion rate
tmin>>tacc: planet
accretion rate = fall-back rate
tmin<<tacc: star
accretion rate << fall-back rate
Released energy

10. CO+star/planet encounters may happenin
dense stellar cluster: randomly
binary/planetary system: natal kick of CO
wide binary: multiple-scattering with field stars  highly eccentric orbits
Quasi-stable triple system: secular evolution  close encounter

11. Dense cluster TDE happens once the closest distance is smaller than Rt
The TD rate for one CO
typically
The TD rate for a stellar cluster
For ~150 globular clusters in Milky Way
BH: 10 Msun
NS: 1.4Msun

12. Natal kick of CO Supernova kick; CO-merger kick
TD probability after kick
Core-collapse SN rate ~3/100yr per galaxy; TDE rate is
1.4E-6/yr for BHs (10Msun) per galaxy
3.4E-7/yr for NSs (1.4Msun) per galaxy
(Neglect poorly known compact binary case, a<10AU)

13. Micro-TDE radiation Duration ~1E4s (True) energy ~ 1E52erg
Super-Eddington: >1010Ledd; jetted
Non-thermal
Rate ~ a fewE-6 per yr per galaxy
10’s/yr Gpc3 (tens times GRB rate)
X/gamma sky monitors may observe many micro-TDEs.

14. Ultra-long GRBs
Liso ~1E49 erg/s
T~1E4 s

15. Application: Ultra-long GRB 111209A
SN 2011kl
Short SN-GRB delay: <day
compact binary; post common-envelope phase
Greiner et al. 2015

16. Application: Short GRB 050709
x-ray flare 16 d after GRB
NS-NS + planet:
BH kick at birth  planet disruption
Fox et al. 2005

17. Neutrino from micro-TDE accretion disc
High mass accretion rate  hot disc  ignite neutrino production
JUNO detection rate
Neutrino energy/spectrum comparable to SN
JUNO can detect 1 nu for SN at <~1Mpc
1 Micro-TDE per <108yr
much rare  diffuse neutrino from micro-TDE
Stacking search for EM-detected micro-TDE?
X/gamma monitor – JUNO
Nearby micro-TDE (lucky?)

18. Observations help to narrow down the large uncertainties.