1. Orsay-2014 Coherent radiation at collisions of short bunches of relativistic particles
N.F. Shul’ga
Akhiezer Institute for Theoretical Physics,
National Science Center “Kharkov Institute of Physics and Technology”
Kharkov, Ukraine

2. Radiation in thin target (TSF-effect)
F. Ternovskii, JETF 1960, N. Shul’ga, S. Fomin JETP Lett. 1978, 1996
suppression of radiation 2

3. Radiation in thin layer of amorphous medium (TSF-effect) N. Shul’ga, S
Radiation in thin layer of amorphous medium (TSF-effect) N. Shul’ga, S. Fomin, 1978 3

4. U. Uggerhøj : … we have seen the half - bare electron !
Suppression of radiation by relativistic electrons in a thin layer of matter (TSF effect), experiment
Predicted at KIPT N.F.Shul’ga, S.P.Fomin, JETP Letters, 27(1978)126.
Confirmed at CERN H.D.Thomsen et al., Physics Letters B 672 (2009) 323.
H.D.Thomsen et al., Physical Review D 81 (2010)
A.S.Fomin, S.P.Fomin, N.F.Shul’ga
Nuovo Cimento (2011)
CERN NA63 SPS E = 149 GeV
U. Uggerhøj : … we have seen the half - bare electron !

5. Evolution of electromagnetic field at electron’s scattering
E.Feinberg JETP 50(1966)202, A. Akhiezer, N.Shul’ga, S.Fomin Sov.Phys.Usp. 30(1987)197
Phys.Lett.A 114(1986)148

7. Coherent Bremsstrahlung (CB) at interaction with atomic string A. I
Coherent Bremsstrahlung (CB) at interaction with atomic string A.I. Akhiezer, N.F. Shul’ga, 1975 7

8. CB on N atoms of string A.I. Akhiezer, N.F. Shul’ga, 1975
CB suppression

9. CB in ultrathin crystal
H. Thomsen et al.
Phys. Rev. D81 (2010)
Ta, L~5μm
P.R.L. 108 (2012)
Ferrara, Italy
Construction of Si crystals
with L50nm 9

10. CB in ultrathin crystal (eikonal approximation) N. Shul’ga, S
CB in ultrathin crystal (eikonal approximation) N.Shul’ga, S.Shul’ga, Phys. Lett. A378 (2014) 3074 10

11. Scattering and CB in ultrathin crystal N. Shul’ga, S. Shul’ga, Phys
Scattering and CB in ultrathin crystal N.Shul’ga, S.Shul’ga, Phys. Lett. A378 (2014) 3074 11

12. CB and suppression of CB in ultrathin crystal12

13. Conclusions 1. Validity conditions
2. The proposed method can be also used for study of:
a) TSF-effect
b) beam-beam coherent radiation 13

14. Radiation in Coulomb field of relativistic particle

15. Coherent radiation at electron-beam collision
I. Ginzburg, G. Kotkin, S. Polityko, V. Serbo
Phys. Lett. B286 (1992) 395
Phys. Rev. E51 (1995) 2493

16. JEPT Lett. 78(2003)700., Proc. of SPIE, v. 5974(2005)60.
Coherent radiation in crystal and at electron collision with a short bunch
crystal atomic string
bunch
N. Shul’ga, D. Tyutyunnik,
JEPT Lett. 78(2003)700., Proc. of SPIE, v. 5974(2005)60.

17. Suppression of coherent radiation (analog of LPM-effect)
ε=5 Gev, L=0.1 cm, ρ=0.01 cm, N=1010,
N. Shul’ga, D. Tyutyunnik. JETP Lett. 78 (2003) 700.
NiM B227 (2005) 152

18. Thank you for
your attention!