1. Potential Gamma-ray Emissions from Low-Mass X-ray Binary Jets
2015, ApJ, arXiv: , in press
张建福
合作者： 顾为民, 刘彤, 薛力, 卢炬甫(导师)
厦门大学 天文学系

2. Outline
★ Introduction
★ Model & Application
★ Summary

3. ★ Introduction  Relativistic radio jet  Accretion-power jet
 X-ray binary
 Relativistic radio jet
 Accretion-power jet
 Microquasar
(Mirabel et al. 1992, Nature) 1E 3

4. So far, ~300 XRBs,~20 MQs
(From Gabriela Vila’s PhD thesis, 2012)

5. The origin of X-ray emissions?
Observations & Implications:
at low energy bands
The origin of X-ray emissions?
 Jet models (e.g., Markoff et al. 2001,2003,2005, Pe’er & Markoff 2012)
ADAF models (e.g., Yuan,Cui & Narayan 2005,ApJ)
Jet + ADAF models
Jet emitting disk models (e.g., Zhang & Xie 2013,MNRAS)
Disk corona-jet models (Qiao & Liu 2015,MNRAS)

6.  Five HMMQs observed at GeV and TeV bands:
Observations & Implications:
at high energy (GeV) and very high energy (TeV) bands
 Five HMMQs observed at GeV and TeV bands:
Cyg X-1, Cyg X-3, SS433, LS 5039, LS I
 LMMQs with lacking gamma-ray signature
Cannot produce any gamma-ray emission;
Are emitting gamma-rays, but not be detected.

7. Hadronic emission models
 Photon emission: Romero & Vila (2008), A&A; Vila & Romero (2010), MNRAS; Vila, Romero & Casco (2012),A&A
Protron Epmax >10^15 eV
Electron Eemax~10^10 eV
Complex spectral distribution
 Neutrino emission:
Zhang et al. (2010), MNRAS
 Adrián-Martínez et al. (2014),
JHEAp, by ANTARES telescope

8. Ratio of proton to electron number is close to 1
1) Spectral fitting of jet emissions (Vila & Romero 2010, MNRAS, Vila, Romero & Casco 2012, A&A);
2) Neutrino observations (Adrián-Martínez et al. 2014, JHEAp);
3) Studies from other objects, such as SNRs.
PIC simulations demonstrate the presence of very strong coupling between e and p (Spitkovsky 2008; Sironi & Spitkovsky 2011), which implies that the mostly dissipated energies are converted into electrons.
Motivate us to study LMMQs by a pure leptonic radiation model
Radiation: electrons
Dynamics: Magnetic field & cold-protron matter

9. ★ Model & Application Based on our models for HMMQs:
Zhang, Xu & Lu 2014, ApJ
Zhang & Lu 2015, ApJ
1) Remove companion effect
2) Add corona component
3) Consider an irradiated disk

10. Electron Spectra
Photon Spectra

11. Application to GX 339-4
Corona dominates X-ray emissions

12. Jet dominates X-ray emissions

13. ★ Summary 1. Propose a pure leptonic radiation model for LMXRBs.
2. Synchrotron + SSC dominates broadband emissions, which is similar to BL Lac object emissions.
3. Not only can our model alternatively explain the emissions ranging from radio to X-ray bands, but also it can predict the potential gamma-ray emission.
4. Can be used to distinguish the origin of X-ray emissions.

14. Thank you!