AARP @ Beams Channeling: from the Past to the Future

15 Nov 2022, 15:00 → 15 May 2023, 17:00 Europe/Zurich

CERN

Sultan Dabagov

 

 

The AARP series of international meetings - Advanced Accelerator & Radiation Physics seminars -  is dedicated to frontier topics in fundamental and applied research associated with new techniques of beam acceleration, novel powerful radiation sources, and applications based on radiation physics. Previous events were held at NRNU MEPhI and  the National Laboratories of Frascati (LNF INFN), at CERN, at the Naples' Institute of Engines (IM CNR), the CEA Cadarache Research Center, and many Universities in Europe. They were dedicated to novel techniques for electron beam acceleration, to advanced methods for free electron lasing, to Compton scattering of relativistic electrons in a strong laser field, to the laser-plasma wakefield acceleration technique, advanced X-ray optical solutions for studying both fundamental and applied physics (e.g., incoherent and coherent X-ray imaging by tabletop facilities), novel X-ray spectroscopy instrumentation, powerful X-ray source studies by means of polycapillary optics, etc., as well as research performed in the framework of various international collaborations.

 

This series of the online seminars will be formed by the invited lectures dedicated to the selected topics of the beams channeling physics and related researches as defined at the international conference "Charged & Neutral Particles Channeling Phenomena". The list of the topics as well as other details are available at the official websites of the last past event Channeling 2018 /Ischia, Italy/ and planned one - Channeling 2020/21/22...23 /Riccione, Italy/  (to be updated for the period of June 4-9, 2023). We are planning several lectures in one-two weeks distance between them. 

 

At the first seminar on November 15, 2022 there will be presented two lectures:  

 

• The introductory notes by Sultan Dabagov (INFN Laboratori Nazionali di Frascati)
  • "Advanced Beams Channeling: from Crystal to Laser/Plasma/Capillary Based Guides"
• Laura Bandiera (INFN Ferrara) 
  • "Crystal Channeling Studies at Modern Accelerator Facilities"

 

Next seminars will be formed by the lectures of Prof. Vladimir Baryshevsky, Prof. Nikolay Kalashnikov, Dr. Robert Chehab, Dr. Giuseppe Dattoli, Prof. Wolfgang Wagner - who already confirmed their lectures, Dr. Frank Zimmermann, Dr. Vladimir Shiltsev, Dr. Sebastien Corde - who confirmed their availability, and others invited by your recommendations and proposals.

 

As planned we will have at least one seminar every two weeks, with the possibility of a slight shift both in days of the week and in time due to the large time difference for potential seminar participants.

 

We invite all interested colleagues to join the seminar at a zoom-service available via the following link: https://cern.zoom.us/j/68853121074?pwd=emZmYXUwTDQ5NGhVMWZEN1BUeXVXZz09

 

 

Tuesday 15 November

1 Advanced Beams Channeling: from Crystal to Laser/Plasma/Capillary Based Guides

Some introductory notes on present main topics of channeling physics

Speaker: Sultan Dabagov

dabagov_aarp-channel2022.pdf

2 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

@ Xavier ARTRU:

Is it possible to have a dedicated lecture on a plasma channeling?

 

@ Sultan DABAGOV:

• We are going to propose one lecture on the features of the formalism of beams channeling for a wake-field acceleration technique, so called a plasma channeling. Indeed, as shown, main peculiarities of the beam dynamics in a plasma channel could be successfully described within the phenomenology of a beam channeling in such a channel.

 

3 Crystal Channeling Studies at Modern Accelerator Facilities

Recent results on channeling of relativistic charged beams in crystals within several international collaborations performing studies at European and US accelerator facilities will be presented.

Speaker: Laura Bandiera (INFN Ferrara, Ferrara (IT))

AARP@BeamsChanneling-15Nov2022-v2.pdf

4 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Additionally to the "vivo" online discussion, a post-discussion is opened here:

 

Tuesday 22 November

5 Channeling tools for high-energy and particle physics

Speaker: Prof. Vladimir Baryshevsky (BSU)

BARYSHEVSKY- 2022 Дабагов 22 November.pdf

6 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Additionally to the "vivo" online discussion, a post-discussion is opened here:

Tuesday 6 December

7 Classical and Quantum Description of Channeling Effect as Mutually Complementary Approximations

Basic principles of channeling phenomenon will be discussed based on classical and quantum features of the projectiles interaction in the structured fields for channeling paying attention to:
1. The models of averaged planar and axial channeling potentials.
2. Approaches that help to obtain analytical results without numerical calculations:
- co-moving reference system (CMRS);
- mixed quantum–classical approaches;
- interpreting the crystal lattice potential as a flow of ‘photons’ in CMRS;
- re-using known results from quantum and atomic physics.
3. Examples of applying simplified analytical approaches:
- calculations of energy levels for transverse motion and radiation spectra;
- estimations of radiation intensity by channeled electrons;
- inverse Compton scattering in crystals, resulting in conversion of electron energy into one photon.

Speakers: Prof. Nikolay Kalashnikov, Dr Andrey Olchak

2022_Channeling_Quant-Classic.pdf

8 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Additionally to the "vivo" online discussion, a post-discussion is opened here:

Tuesday 13 December

9 Theoretical and Phenomenological Aspects of Compton Back-Scattering Light Sources - Lecture 1

Along with the development of FEL X-ray sources, the design and the construction of Compton Back-Scattering (CBS) devices for different applications, are being pursued. These sources are designed to provide monochromatic, high peak brightness tunable light beams, with photon energies above 10keV.
The source brightness is the most significant figure of merit, which specifies the suitability of X-ray beams for their application in a specific field of interest and also reflects the quality of the electron beam itself, which in turn depends on the charge, emittance, energy spread…
In this seminar we review the theory of Thomson and Compton backscattering in intense laser waves, discuss the analogies with the emission in static undulators and discuss the possibility of observing a new phenomenology in extreme QED conditions. We show how simple theoretical considerations and few analytical formulae provide straightforward tools for the design of CBS X-ray sources. The attempt we foresee is analogous to previous efforts, put forward to model Free Electron Laser devices, using scaling relations accounting for the entanglement between the different physical quantities contributing to the output beam performances.
We benchmark the reliability of the method making a comparison with more general computations (including the numerical option) and data available in the dedicated literature.

Speaker: Dr Giuseppe Dattoli

Giuseppe Dattoli.pptx-2.pdf

Tuesday 20 December

10 Theoretical and Phenomenological Aspects of Compton Back-Scattering Light Sources - Lecture 2

Along with the development of FEL X-ray sources, the design and the construction of Compton Back-Scattering (CBS) devices for different applications, are being pursued. These sources are designed to provide monochromatic, high peak brightness tunable light beams, with photon energies above 10keV.
The source brightness is the most significant figure of merit, which specifies the suitability of X-ray beams for their application in a specific field of interest and also reflects the quality of the electron beam itself, which in turn depends on the charge, emittance, energy spread…
In this seminar we review the theory of Thomson and Compton backscattering in intense laser waves, discuss the analogies with the emission in static undulators and discuss the possibility of observing a new phenomenology in extreme QED conditions. We show how simple theoretical considerations and few analytical formulae provide straightforward tools for the design of CBS X-ray sources. The attempt we foresee is analogous to previous efforts, put forward to model Free Electron Laser devices, using scaling relations accounting for the entanglement between the different physical quantities contributing to the output beam performances.
We benchmark the reliability of the method making a comparison with more general computations (including the numerical option) and data available in the dedicated literature.

Speaker: Dr Giuseppe Dattoli

Giuseppe Dattoli.pptx-2.pdf

11 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Additionally to the "vivo" online discussion, a post-discussion is opened here:

 

@ Anton BABAEV

The formula for luminosity in slide 22 is exact for Gaussian beams only. So, it is interesting what beams are used in a practice (the remark is more relevant for laser beam than for electron one, I guess).

This formula can be used for estimation of the order of the effect, but it should be modified taking into account real beam profiles for more or less precise calculations.

 

@ Giuseppe DATTOLI:

 

The formula in slide 22 is valid, but it is just the result of a wise collection og physical quantities. 

In slide (35) I have reported what that formula misses. A very accurate and thoghtful calculation is reported in the article Hartemann, F. V. ; Brown, W. J.; Gibson, D. J.; Anderson, S. G. ; Tremaine, A. M. ; Springer, P. T.; Wootton, A. J. ; Hartouni, E.P. and Barty, C. P. J., High-energy scaling of Compton scattering light sources., Phys. Rev. Accel. Beams,vol. 21(8), pp. 100702 (2005) - https://doi.org/10.1103/PhysRevSTAB.8.100702, In which the various steps for a complete account of the electron and laser beam profiles is included. 

 

The calculations are however limited to the spatial parts, including the 4-D phase space, in terms of Gaussian distributions.

 

A more general calculation should however be based on the use of the Wigner transform with the inclusion of the whole 6-D phase space structure. 

The analysis with non-gaussian profiles has not yet been done (as far I know), I have the impression that long tail electron beams as those from plasma acceleration, could provide significant differences. However if distortion are not significant an expansion in terms of Gauss Hermite beams, could, in principle be used, to infer possible deviations.

Tuesday 10 January

12 Significance of Singularities for Channeling of Ions into Nanostructured Materials

The analysis of channeling of classical particles through nanostructured materials starts with examination of Newton’s equations. The ion – material interaction potential is constructed from the thermally averaged ion – atom interaction potential. Small angle scattering approximation is used, thus nanostructured material can be considered as a collection of the continuously charged atomic strings and planes. Newton’s equations were solved numerically with initial conditions derived from the initial positional and angular distributions of the ion beam.
Trajectories generate mappings of the ion impact parameter to the final transmitted angle and final transverse position, respectively. It will be shown that singular lines of these mappings, called rainbows, correspond to the singular peaks of the differential cross-sections and transmitted yields, respectively. The analysis of the associated Jacobian will show that the rainbow effect is a collective or gestalt effect. The inverse mappings of the final transverse spatial and angular position to the initial position, called equilibrium surfaces, are multivalued. Locally, change of the multiplicity and, subsequently, change of the rainbow lines is modeled by the catastrophe theory. Moreover, it is possible to find an appropriate catastrophe of higher order which is globally valid model of rainbow lines. It will be shown that all important features of the rainbow channeling effect are related to the morphological properties of equilibrium surfaces. Long time dynamics of the rainbow lines will be also examined.
When transmitted particles show quantum behavior, it has been shown that the rainbow channeling effect still exists. The developed morphological method is applied to families of the probability density and phase function, obtained from the numerical solution of the corresponding Schrödinger equation. Initially, each particle is represented by the Gaussian wave packet with the mean value and variance derived from the initial positional and angular distributions of the ion beam. It has been shown that classical Hamilton’s principal function and corresponding family of quantum Hamilton’s principal functions share the same behavior – the cusp singularities, which are distinctive signature of the rainbow effect.
Some applications of the rainbow channeling: deducing the correct ion-atom interaction potential, realization of subatomic microscopy, characterization of the nanotubes, will be also discussed.

Speaker: Prof. Marko Ćosić (University of Belgrade)

cosic_presentation.pdf

related papers

• Cosic-Petrovic-Bellucci-Rainbow channeling of protons in very short carbon nanotubes with aligned Stone–Wales defects.pdf
• Cosic-Petrovic-Neskovic-Quantum primary rainbows in transmission of positrons through very short carbon nanotubes.pdf
• Petrovic-Cosic-Neskovic-Quantum rainbow channeling of positrons in very short carbon nanotubes.pdf
• Petrovic-Neskovic-Berec-Cosic-Superfocusing of channeled protons and subatomic measurement resolution.pdf
• Petrovic-Neskovic-Cosic-Proton–silicon interaction potential extracted from high-resolution.pdf

13 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Additionally to the "vivo" online discussion, a post-discussion is opened here:

 

@ Serguei Fomin:

 

Dear Sultan and Marko,

Thanks a lot Sultan for organizing these seminars and a great opportunity to communicate with colleagues and friends. It was very pleasant and interesting to listen to Marco's presentation on rainbow scattering in crystals and nanotubes, which reminded me of my early works on the physics of the interaction of relativistic electrons and positrons with crystals in 70th years. At that time we did not have computers yet, and at first the calculations were carried out only analytically. Just in case, here are links to our somewhat pioneering work 😄 :
- S.P. Fomin, N.F. Shul’ga, Rainbow scattering and orbiting of fast particles in crystal. Phys. Lett. A73 (1979) 131-133.
- N.F. Shul’ga, V.I. Truten’, Interference effects in string scattering of fast particles in crystal. Phys. Lett. A96 (1983) 107-110.
- N.F. Shul’ga, V.I. Truten’, Orientation effects in interaction of high-energy particles with strings of atoms in a crystal. Sov Phys JETP 60 (1984) 145-152.
When nanotubes appeared, we considered similar effects for them as well (see our review X. Artru et al. ‘Carbon_nanotubes …', Physics Reports 412 (2005) 89-189 (see Figs 17-20). In our papers, we considered the scattering mainly of over-barrier relativistic electrons and positrons.

Marco, you have obtained very interesting results, which may also be of great practical importance. Asking you about the influence of thermal oscillations and the incoherent scattering associated with them, I had in mind the influence of the corresponding fluctuations of the continuous field of SWNT, leading to nonconservation of the energy of the transverse motion of particles, and which can have a destructive effect on interference picture. In a diamond crystal, the amplitude of thermal vibrations is, of course, very small, however, in the case of SWNT, this may not be the case due to the significant anisotropy of thermal vibrations of atoms in transverse direction to the "graphene" wall of the nanotube.

For the last twenty years I have been engaged in the physics of innovative nuclear reactors. But I know that in recent years, Nikolai and Sergey Shul'ga from my institute, NSC KIPT, have been studying quantum effects in the scattering of fast particles in thin and ultrathin crystals... I told him (N. Shul'ga) about your work and gave a link to the presentation and your publications. He said that he knows the earlier work of your colleagues N. Neškovič and B. Petrovič and refers to their work in his monograph on scattering theory.

 

 

@ Marko Cosic:

Dear Sultan,

Sorry for the late response. I have received the invitation and the confirmation letter... I was honored to be invited to give a talk and exchange scientific ideas with Sergei Fomin and others. I believe this result should be valued more than simple participation in some ordinary conference.

After the online seminar, I was in Croatia performing experiments on the rainbow channeling of protons in thin silicon Crystals. We have successfully detected the change of the angular distribution from an “x” like shape to a “+” like, followed by observation of the intense maximum at the center at the point of the transition. In other words, we have finally experimentally confirmed the existence of the zero-degree focusing effect that was theocratized to exist many years ago. 

Tuesday 31 January

14 Use of Channeling Radiation for New Positron Sources

We are reporting, hereafter, the works initiated at Orsay more than thirty years ago and developped further in LAL-Orsay and in other laboratories. They are concerning the use of crystal effects which are of interest for a new kind of positron source. After short considerations on some crystal effects which are providing gamma rays able to generate e-/e+ pairs in a converter, emphasis is put on axial channeling radiation : its characteristics like the radiated energy and the photon yield appeared important enough to be chosen as the source of photons to generate e-e+ pairs. Two configurations are, then, considered : in the first one the axially oriented crystal is the converter : radiation and pair production are both occuring in the crystal. The second one separates the radiation and the conversion using a thin crystal for the radiation and a thick amorphous material for the conversion. Such combination of a radiator and a converter led to the hybrid scheme. The challenges, as heating and radiation damages, met by the two configurations are analysed.

A review of the experiments worked out at LAL- Orsay, CERN, KEK and SLAC is given. These experiments provided informations on the specificity of the radiated photons (Orsay), the positron yield, positron spectrum and the phase space for a thick crystal-converter (CERN), the yield for a crystal converter and for an hybrid scheme (KEK) and the radiation damages (SLAC). Recent improvements on the hybrid scheme using a granular converter instead of a bulk converter leading to some tests at KEK are also described.

A short presentation of the projects of positron sources for linear and circular colliders which have involved IJCLab in collaboration with other laboratories is also given. Tests related to the studies of the challenges met by the positron sources started and are in development at MAMI (Mainz), DESY (Hamburg) and KEK (Tsukuba) and CERN. These tests are carried out with the involvement of large collaborations including IJCLab, INFN-Ferrara, CERN, PSI and KEK and with the technical support of MAMI, DESY and CERN. A short review of these tests is also given.

Summarising, the interest of such way to generate positrons is underlined and some perspectives indicated.

Speaker: Robert Chehab (INSTITUT DE PHYSIQUE NUCLEAIRE DE LYON-IN2P3/CNRS (France))

15 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

Babaev_2016_J._Phys._Conf._Ser._732_012030.pdf

babaev3-rep.pdf

  

Additionally to the "vivo" online discussion, a post-discussion is opened here:

@ Anton BABAEV:

 

Dear Sultan,

 

just remark about thermal stress in diamond target. Indeed, diamond is pespective material for targets/detectors due to its highest thermal conductivity (it means reduced demands for external cooling).

There is just reference to the paper on the subject (not for hybrid positron source conditions, though). Probably, it could be of interest for Prof. Chehab. 

https://iopscience.iop.org/article/10.1088/1742-6596/732/1/012030
 

 

Best regards,

Anton.

 

@ Sultan DABAGOV:

 

Dear Anton,

Thank you so much for active participation in the work of our seminar!

I’m grateful for your comment with a link to rather interesting paper, that in cc now becomes available also to Robert (below, after my mail). 

Next days your note will be published also in the lecture’s minutes.

 

Dear Robert, you can reply to the comment either directly writing in the minutes or sending me your answer. Thanks again for your very attractive lecture!

 

With kind wishes,     Sultan

 

 

@ Robert CHEHAB:

 

Dear Colleagues,
 

                           Thank you for this messge. I shall look trough the article of Anton and communicate later on. Thanks again , Sultan, for these nice meetings where it is the occasion to hear many colleagues already met at RREPS or Channeling symposia. 
 

                                                  With best regards
 

                                                 Robert

 

 

Dear Sultan, Dear Anton,
 

                                       I read the  interesting article of A.A.Babaev and A.S.Gogolev. The problematics are the same as in positron targets where the reliability is depending from the possible damages due to intense power deposition in small volumes of the target. In the attached note I tried to present an approach to this problem. I must underline that I found some discrepancies in the documentation concerning the diamond. As , for instance, for the tensile strengths. That is why this note is more qualitative than quantitative.
 

                                                                  With best regards
 

                                                                   Robert

 

 

@ Anton BABAEV:

 

Dear Robert,

 

thank you for your note.

Indeed, we calculated waves of deformation with COMSOL (that is like ANSYS) and published results in Russian-language journal in 2018 (I thought we published them in the paper I’ve sent….)

We found that the first bunch produced maximal von-Mises stress 2.2 GPa (that is close to your estimation; although I am not sure our approaches are completely the same), so we decided the target was broken.

 

Best regards,

Anton.

Tuesday 14 February

16 Energy Recovery Linacs - a Way Towards Energy Sustainability of Particle Accelerators

Energy Recovery Linacs (ERL) are emerging as a new generation of particle accelerators that promises the maximum energy sustainability. Based on Super-conducting Radio-Frequency cavities, and a smart multiple propagation of the electron beam through the Linear accelerator, they aim at reaching beam average current levels typical of storange rings (from tens up to hundreds of mA), normally forbidden to linear accelerators (Linacs) due to the large beam power levels involved (well above the MW scale). In fact ERLs will be able to deliver high brightness electron beams, as requested by advanced radiation sources like FEL’s or ICS, together with very large average beam current/power, while recovering after use (by means of beam deceleration in the Linac) the large amount of power stored in the beam. They grant users/experiments with full access to the beam phase space, but only perturbative acess to the beam power (no fixed target experiments allowed): the user can degrade the beam quality but cannot waste the particles in the beam. Consequently, only radiation emission and/or beam collisions experiments can be carried out with ERLs. A discussion of the basics of acceleration/deceleration process will be presented, followed by an overview of ongoing projects that are demonstrating the basic ERL principle, and future designs of large scale ERLs for the high energy frontier (electron-positrons or electron-hadron collisions for Higgs factories and fundamental physics, secondary muon beams for muon colliders, etc).

Speaker: Luca Serafini (INFN-Milan/LASA & Univ. of Milan)

17 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.

  

Additionally to the "vivo" online discussion, a post-discussion is opened here:

Tuesday 14 March

18 Radiation of Surface Polaritons in Cylindrical Waveguides

We discuss the emission of surface polaritons by a charged particle propagating on a cylindrical interface between two media. Two cases of the charge motion are considered: a charge rotating around the cylinder and a charge moving parallel to the axis of the cylinder. The corresponding radiation intensities are presented and the features of the radiation are discussed. The radiation is present in the spectral range where the dielectric permittivities of the cylinder and surrounding medium have opposite signs. The spectral range of the emitted surface polaritons becomes narrower with decreasing energy of the particle. The general results are illustrated for a special case of the Drude model for dispersion of the dielectric permittivity of the cylinder. In addition to surface polaritons, the Cherenkov and synchrotron radiations are discussed as well.

Speaker: Prof. Aram Saharian (IAPP NAS RA & Uni Yerevan)

19 Discussion

Additionally to the "vivo" online discussion, a post-discussion is opened. Any questions and comments are welcome - please, submit them directly to sultan.dabagov@cern.ch
They will be published directly via the Minutes option of the Discussion.