ImpactX
RFCavity.H
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1 /* Copyright 2022-2023 The Regents of the University of California, through Lawrence
2  * Berkeley National Laboratory (subject to receipt of any required
3  * approvals from the U.S. Dept. of Energy). All rights reserved.
4  *
5  * This file is part of ImpactX.
6  *
7  * Authors: Chad Mitchell, Axel Huebl
8  * License: BSD-3-Clause-LBNL
9  */
10 #ifndef IMPACTX_RFCAVITY_H
11 #define IMPACTX_RFCAVITY_H
12 
15 #include "mixin/alignment.H"
16 #include "mixin/beamoptic.H"
17 #include "mixin/thick.H"
18 
19 #include <ablastr/constant.H>
20 
21 #include <AMReX.H>
22 #include <AMReX_Array.H>
23 #include <AMReX_Extension.H>
24 #include <AMReX_REAL.H>
25 
26 #include <array>
27 #include <cmath>
28 #include <stdexcept>
29 #include <tuple>
30 #include <vector>
31 
32 
33 namespace impactx
34 {
45  {
47  0.1644024074311037,
48  -0.1324009958969339,
49  4.3443060026047219e-002,
50  8.5602654094946495e-002,
51  -0.2433578169042885,
52  0.5297150596779437,
53  0.7164884680963959,
54  -5.2579522442877296e-003,
55  -5.5025369142193678e-002,
56  4.6845673335028933e-002,
57  -2.3279346335638568e-002,
58  4.0800777539657775e-003,
59  4.1378326533752169e-003,
60  -2.5040533340490805e-003,
61  -4.0654981400000964e-003,
62  9.6630592067498289e-003,
63  -8.5275895985990214e-003,
64  -5.8078747006425020e-002,
65  -2.4044337836660403e-002,
66  1.0968240064697212e-002,
67  -3.4461179858301418e-003,
68  -8.1201564869443749e-004,
69  2.1438992904959380e-003,
70  -1.4997753525697276e-003,
71  1.8685171825676386e-004
72  };
73 
75  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
76  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
77  0, 0, 0
78  };
79  };
80 
87 namespace RFCavityData
88 {
90  static inline int next_id = 0;
91 
93  static inline std::map<int, std::vector<amrex::ParticleReal>> h_cos_coef = {};
95  static inline std::map<int, std::vector<amrex::ParticleReal>> h_sin_coef = {};
96 
98  static inline std::map<int, amrex::Gpu::DeviceVector<amrex::ParticleReal>> d_cos_coef = {};
100  static inline std::map<int, amrex::Gpu::DeviceVector<amrex::ParticleReal>> d_sin_coef = {};
101 
102 } // namespace RFCavityData
103 
104  struct RFCavity
105  : public elements::BeamOptic<RFCavity>,
106  public elements::Thick,
107  public elements::Alignment
108  {
109  static constexpr auto name = "RFCavity";
111 
128  amrex::ParticleReal ds,
129  amrex::ParticleReal escale,
130  amrex::ParticleReal freq,
131  amrex::ParticleReal phase,
132  std::vector<amrex::ParticleReal> cos_coef,
133  std::vector<amrex::ParticleReal> sin_coef,
134  amrex::ParticleReal dx = 0,
135  amrex::ParticleReal dy = 0,
136  amrex::ParticleReal rotation_degree = 0,
137  int mapsteps = 1,
138  int nslice = 1
139  )
140  : Thick(ds, nslice),
141  Alignment(dx, dy, rotation_degree),
142  m_escale(escale), m_freq(freq), m_phase(phase), m_mapsteps(mapsteps)
143  {
144  // next created RF cavity has another id for its data
146 
147  // validate sin and cos coefficients are the same length
148  m_ncoef = int(cos_coef.size());
149  if (m_ncoef != int(sin_coef.size()))
150  throw std::runtime_error("RFCavity: cos and sin coefficients must have same length!");
151 
152  // host data
153  RFCavityData::h_cos_coef[m_id] = cos_coef;
154  RFCavityData::h_sin_coef[m_id] = sin_coef;
157 
158  // device data
162  cos_coef.begin(), cos_coef.end(),
163  RFCavityData::d_cos_coef[m_id].begin());
165  sin_coef.begin(), sin_coef.end(),
166  RFCavityData::d_sin_coef[m_id].begin());
168 
169  // low-level objects we can use on device
172  }
173 
175  using BeamOptic::operator();
176 
191  amrex::ParticleReal & AMREX_RESTRICT x,
192  amrex::ParticleReal & AMREX_RESTRICT y,
193  amrex::ParticleReal & AMREX_RESTRICT t,
194  amrex::ParticleReal & AMREX_RESTRICT px,
195  amrex::ParticleReal & AMREX_RESTRICT py,
196  amrex::ParticleReal & AMREX_RESTRICT pt,
197  [[maybe_unused]] uint64_t & AMREX_RESTRICT idcpu,
198  [[maybe_unused]] RefPart const & refpart
199  ) const
200  {
201  using namespace amrex::literals; // for _rt and _prt
202 
203  // shift due to alignment errors of the element
204  shift_in(x, y, px, py);
205 
206  // intialize output values
207  amrex::ParticleReal xout = x;
208  amrex::ParticleReal yout = y;
209  amrex::ParticleReal tout = t;
210 
211  // initialize output values of momenta
212  amrex::ParticleReal pxout = px;
213  amrex::ParticleReal pyout = py;
214  amrex::ParticleReal ptout = pt;
215 
216  // get the linear map
218 
219  // symplectic linear map for the RF cavity is computed using the
220  // Hamiltonian formalism as described in:
221  // https://uspas.fnal.gov/materials/09UNM/ComputationalMethods.pdf.
222  // R denotes the transfer matrix in the basis (x,px,y,py,t,pt),
223  // so that, e.g., R(3,4) = dyf/dpyi.
224 
225  // push particles using the linear map
226  xout = R(1,1)*x + R(1,2)*px + R(1,3)*y
227  + R(1,4)*py + R(1,5)*t + R(1,6)*pt;
228  pxout = R(2,1)*x + R(2,2)*px + R(2,3)*y
229  + R(2,4)*py + R(2,5)*t + R(2,6)*pt;
230  yout = R(3,1)*x + R(3,2)*px + R(3,3)*y
231  + R(3,4)*py + R(3,5)*t + R(3,6)*pt;
232  pyout = R(4,1)*x + R(4,2)*px + R(4,3)*y
233  + R(4,4)*py + R(4,5)*t + R(4,6)*pt;
234  tout = R(5,1)*x + R(5,2)*px + R(5,3)*y
235  + R(5,4)*py + R(5,5)*t + R(5,6)*pt;
236  ptout = R(6,1)*x + R(6,2)*px + R(6,3)*y
237  + R(6,4)*py + R(6,5)*t + R(6,6)*pt;
238 
239  // assign updated values
240  x = xout;
241  y = yout;
242  t = tout;
243  px = pxout;
244  py = pyout;
245  pt = ptout;
246 
247  // undo shift due to alignment errors of the element
248  shift_out(x, y, px, py);
249  }
250 
256  void operator() (RefPart & AMREX_RESTRICT refpart) const
257  {
258  using namespace amrex::literals; // for _rt and _prt
259 
260  // assign input reference particle values
261  amrex::ParticleReal const x = refpart.x;
262  amrex::ParticleReal const px = refpart.px;
263  amrex::ParticleReal const y = refpart.y;
264  amrex::ParticleReal const py = refpart.py;
265  amrex::ParticleReal const z = refpart.z;
266  amrex::ParticleReal const pz = refpart.pz;
267  amrex::ParticleReal const pt = refpart.pt;
268  amrex::ParticleReal const s = refpart.s;
269  amrex::ParticleReal const sedge = refpart.sedge;
270 
271  // initialize linear map (deviation) values
272  for (int i=1; i<7; i++) {
273  for (int j=1; j<7; j++) {
274  if (i == j)
275  refpart.map(i, j) = 1.0_prt;
276  else
277  refpart.map(i, j) = 0.0_prt;
278  }
279  }
280 
281  // length of the current slice
282  amrex::ParticleReal const slice_ds = m_ds / nslice();
283 
284  // compute intial value of beta*gamma
285  amrex::ParticleReal const bgi = sqrt(pow(pt, 2) - 1.0_prt);
286 
287  // call integrator to advance (t,pt)
288  amrex::ParticleReal const zin = s - sedge;
289  amrex::ParticleReal const zout = zin + slice_ds;
290  int const nsteps = m_mapsteps;
291 
292  integrators::symp2_integrate_split3(refpart,zin,zout,nsteps,*this);
293  amrex::ParticleReal const ptf = refpart.pt;
294 
295  // advance position (x,y,z)
296  refpart.x = x + slice_ds*px/bgi;
297  refpart.y = y + slice_ds*py/bgi;
298  refpart.z = z + slice_ds*pz/bgi;
299 
300  // compute final value of beta*gamma
301  amrex::ParticleReal const bgf = sqrt(pow(ptf, 2) - 1.0_prt);
302 
303  // advance momentum (px,py,pz)
304  refpart.px = px*bgf/bgi;
305  refpart.py = py*bgf/bgi;
306  refpart.pz = pz*bgf/bgi;
307 
308  // convert linear map from dynamic to static units
309  amrex::ParticleReal scale_in = 1.0_prt;
310  amrex::ParticleReal scale_fin = 1.0_prt;
311 
312  for (int i=1; i<7; i++) {
313  for (int j=1; j<7; j++) {
314  if( i % 2 == 0)
315  scale_fin = bgf;
316  else
317  scale_fin = 1.0_prt;
318  if( j % 2 == 0)
319  scale_in = bgi;
320  else
321  scale_in = 1.0_prt;
322  refpart.map(i, j) = refpart.map(i, j) * scale_in / scale_fin;
323  }
324  }
325 
326  // advance integrated path length
327  refpart.s = s + slice_ds;
328  }
329 
336  std::tuple<amrex::ParticleReal, amrex::ParticleReal, amrex::ParticleReal>
338  RF_Efield (amrex::ParticleReal const zeval) const
339  {
340  using namespace amrex::literals; // for _rt and _prt
341 
342  // pick the right data depending if we are on the host side
343  // (reference particle push) or device side (particles):
344 #if AMREX_DEVICE_COMPILE
345  amrex::ParticleReal* cos_data = m_cos_d_data;
346  amrex::ParticleReal* sin_data = m_sin_d_data;
347 #else
348  amrex::ParticleReal* cos_data = m_cos_h_data;
349  amrex::ParticleReal* sin_data = m_sin_h_data;
350 #endif
351 
352  // specify constants
354  amrex::ParticleReal const zlen = m_ds;
355  amrex::ParticleReal const zmid = zlen / 2.0_prt;
356 
357  // compute on-axis electric field (z is relative to cavity midpoint)
358  amrex::ParticleReal efield = 0.0;
359  amrex::ParticleReal efieldp = 0.0;
360  amrex::ParticleReal efieldpp = 0.0;
361  amrex::ParticleReal efieldint = 0.0;
362  amrex::ParticleReal const z = zeval - zmid;
363 
364  if (std::abs(z) <= zmid)
365  {
366  efield = 0.5_prt*cos_data[0];
367  efieldint = z*efield;
368  for (int j=1; j < m_ncoef; ++j)
369  {
370  efield = efield + cos_data[j]*cos(j*2*pi*z/zlen) +
371  sin_data[j]*sin(j*2*pi*z/zlen);
372  efieldp = efieldp-j*2*pi*cos_data[j]*sin(j*2*pi*z/zlen)/zlen +
373  j*2*pi*sin_data[j]*cos(j*2*pi*z/zlen)/zlen;
374  efieldpp = efieldpp- pow(j*2*pi*cos_data[j]/zlen,2) *cos(j*2*pi*z/zlen) -
375  pow(j*2*pi*sin_data[j]/zlen,2) *sin(j*2*pi*z/zlen);
376  efieldint = efieldint + zlen*cos_data[j]*sin(j*2*pi*z/zlen)/(j*2*pi) -
377  zlen*sin_data[j]*cos(j*2*pi*z/zlen)/(j*2*pi);
378  }
379  }
380  return std::make_tuple(efield, efieldp, efieldint);
381  }
382 
392  void map3 (amrex::ParticleReal const tau,
393  RefPart & refpart,
394  [[maybe_unused]] amrex::ParticleReal & zeval) const
395  {
396  using namespace amrex::literals; // for _rt and _prt
397 
398  // push the reference particle
399  amrex::ParticleReal const t = refpart.t;
400  amrex::ParticleReal const pt = refpart.pt;
401 
402  if (pt < -1.0_prt) {
403  refpart.t = t + tau/sqrt(1.0_prt - pow(pt, -2));
404  refpart.pt = pt;
405  }
406  else {
407  refpart.t = t;
408  refpart.pt = pt;
409  }
410 
411  // push the linear map equations
413  amrex::ParticleReal const betgam = refpart.beta_gamma();
414 
415  refpart.map(5,5) = R(5,5) + tau*R(6,5)/pow(betgam,3);
416  refpart.map(5,6) = R(5,6) + tau*R(6,6)/pow(betgam,3);
417  }
418 
428  void map2 (amrex::ParticleReal const tau,
429  RefPart & refpart,
430  amrex::ParticleReal & zeval) const
431  {
432  using namespace amrex::literals; // for _rt and _prt
433 
434  amrex::ParticleReal const t = refpart.t;
435  amrex::ParticleReal const pt = refpart.pt;
436 
437  // Define parameters and intermediate constants
440  amrex::ParticleReal const k = (2.0_prt*pi/c)*m_freq;
441  amrex::ParticleReal const phi = m_phase*(pi/180.0_prt);
442  amrex::ParticleReal const E0 = m_escale;
443 
444  // push the reference particle
445  auto [ez, ezp, ezint] = RF_Efield(zeval);
446  amrex::ignore_unused(ez, ezint);
447 
448  refpart.t = t;
449  refpart.pt = pt;
450 
451  // push the linear map equations
453  amrex::ParticleReal const s = tau/refpart.beta_gamma();
454  amrex::ParticleReal const L = E0*ezp*sin(k*t+phi)/(2.0_prt*k);
455 
456  refpart.map(1,1) = (1.0_prt-s*L)*R(1,1) + s*R(2,1);
457  refpart.map(1,2) = (1.0_prt-s*L)*R(1,2) + s*R(2,2);
458  refpart.map(2,1) = -s*pow(L,2)*R(1,1) + (1.0_prt+s*L)*R(2,1);
459  refpart.map(2,2) = -s*pow(L,2)*R(1,2) + (1.0_prt+s*L)*R(2,2);
460 
461  refpart.map(3,3) = (1.0_prt-s*L)*R(3,3) + s*R(4,3);
462  refpart.map(3,4) = (1.0_prt-s*L)*R(3,4) + s*R(4,4);
463  refpart.map(4,3) = -s*pow(L,2)*R(3,3) + (1.0_prt+s*L)*R(4,3);
464  refpart.map(4,4) = -s*pow(L,2)*R(3,4) + (1.0_prt+s*L)*R(4,4);
465  }
466 
476  void map1 (amrex::ParticleReal const tau,
477  RefPart & refpart,
478  amrex::ParticleReal & zeval) const
479  {
480  using namespace amrex::literals; // for _rt and _prt
481 
482  amrex::ParticleReal const t = refpart.t;
483  amrex::ParticleReal const pt = refpart.pt;
484  amrex::ParticleReal const z = zeval;
485 
486  // Define parameters and intermediate constants
489  amrex::ParticleReal const k = (2.0_prt*pi/c)*m_freq;
490  amrex::ParticleReal const phi = m_phase*(pi/180.0_prt);
491  amrex::ParticleReal const E0 = m_escale;
492 
493  // push the reference particle
494  auto [ez, ezp, ezint] = RF_Efield(z);
496  zeval = z + tau;
497  auto [ezf, ezpf, ezintf] = RF_Efield(zeval);
499 
500  refpart.t = t;
501  refpart.pt = pt - E0*(ezintf-ezint)*cos(k*t+phi);
502 
503  // push the linear map equations
505  amrex::ParticleReal const M = E0*(ezintf-ezint)*k*sin(k*t+phi);
506  amrex::ParticleReal const L = E0*(ezpf-ezp)*sin(k*t+phi)/(2.0_prt*k)+M/2.0_prt;
507 
508  refpart.map(2,1) = L*R(1,1) + R(2,1);
509  refpart.map(2,2) = L*R(1,2) + R(2,2);
510 
511  refpart.map(4,3) = L*R(3,3) + R(4,3);
512  refpart.map(4,4) = L*R(3,4) + R(4,4);
513 
514  refpart.map(6,5) = M*R(5,5) + R(6,5);
515  refpart.map(6,6) = M*R(5,6) + R(6,6);
516  }
517 
520  void
522  {
523  // remove from unique data map
528 
533  }
534 
535  amrex::ParticleReal m_escale;
536  amrex::ParticleReal m_freq;
537  amrex::ParticleReal m_phase;
539  int m_id;
540 
541  int m_ncoef = 0;
542  amrex::ParticleReal* m_cos_h_data = nullptr;
543  amrex::ParticleReal* m_sin_h_data = nullptr;
544  amrex::ParticleReal* m_cos_d_data = nullptr;
545  amrex::ParticleReal* m_sin_d_data = nullptr;
546  };
547 
548 } // namespace impactx
549 
550 #endif // IMPACTX_RFCAVITY_H
#define AMREX_FORCE_INLINE
#define AMREX_GPU_HOST_DEVICE
#define AMREX_GPU_HOST
static constexpr auto c
static constexpr amrex::Real pi
void copyAsync(HostToDevice, InIter begin, InIter end, OutIter result) noexcept
static constexpr HostToDevice hostToDevice
void streamSynchronize() noexcept
constexpr std::enable_if_t< std::is_floating_point< T >::value, T > pi()
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void ignore_unused(const Ts &...)
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE GpuComplex< T > pow(const GpuComplex< T > &a_z, const T &a_y) noexcept
const int[]
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE GpuComplex< T > sqrt(const GpuComplex< T > &a_z) noexcept
i
static std::map< int, std::vector< amrex::ParticleReal > > h_cos_coef
host: cosine coefficients in Fourier expansion of on-axis electric field Ez
Definition: RFCavity.H:93
static std::map< int, std::vector< amrex::ParticleReal > > h_sin_coef
host: sine coefficients in Fourier expansion of on-axis electric field Ez
Definition: RFCavity.H:95
static std::map< int, amrex::Gpu::DeviceVector< amrex::ParticleReal > > d_sin_coef
device: sine coefficients in Fourier expansion of on-axis electric field Ez
Definition: RFCavity.H:100
static std::map< int, amrex::Gpu::DeviceVector< amrex::ParticleReal > > d_cos_coef
device: cosine coefficients in Fourier expansion of on-axis electric field Ez
Definition: RFCavity.H:98
static int next_id
last used id for a created RF cavity
Definition: RFCavity.H:90
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void symp2_integrate_split3(RefPart &refpart, amrex::ParticleReal const zin, amrex::ParticleReal const zout, int const nsteps, T_Element const &element)
Definition: Integrators.H:51
Definition: ImpactX.cpp:33
@ t
fixed t as the independent variable
s
c
int nsteps
int count
Definition: RFCavity.H:45
amrex::Vector< amrex::ParticleReal > default_sin_coef
Definition: RFCavity.H:74
amrex::Vector< amrex::ParticleReal > default_cos_coef
Definition: RFCavity.H:46
Definition: RFCavity.H:108
amrex::ParticleReal m_escale
Definition: RFCavity.H:535
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void map2(amrex::ParticleReal const tau, RefPart &refpart, amrex::ParticleReal &zeval) const
Definition: RFCavity.H:428
amrex::ParticleReal * m_cos_h_data
number of Fourier coefficients
Definition: RFCavity.H:542
amrex::ParticleReal m_phase
RF frequency in Hz.
Definition: RFCavity.H:537
void finalize()
Definition: RFCavity.H:521
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void operator()(amrex::ParticleReal &AMREX_RESTRICT x, amrex::ParticleReal &AMREX_RESTRICT y, amrex::ParticleReal &AMREX_RESTRICT t, amrex::ParticleReal &AMREX_RESTRICT px, amrex::ParticleReal &AMREX_RESTRICT py, amrex::ParticleReal &AMREX_RESTRICT pt, [[maybe_unused]] uint64_t &AMREX_RESTRICT idcpu, [[maybe_unused]] RefPart const &refpart) const
Definition: RFCavity.H:190
amrex::ParticleReal * m_cos_d_data
non-owning pointer to host sine coefficients
Definition: RFCavity.H:544
int m_mapsteps
RF driven phase in deg.
Definition: RFCavity.H:538
RFCavity(amrex::ParticleReal ds, amrex::ParticleReal escale, amrex::ParticleReal freq, amrex::ParticleReal phase, std::vector< amrex::ParticleReal > cos_coef, std::vector< amrex::ParticleReal > sin_coef, amrex::ParticleReal dx=0, amrex::ParticleReal dy=0, amrex::ParticleReal rotation_degree=0, int mapsteps=1, int nslice=1)
Definition: RFCavity.H:127
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void map1(amrex::ParticleReal const tau, RefPart &refpart, amrex::ParticleReal &zeval) const
Definition: RFCavity.H:476
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void map3(amrex::ParticleReal const tau, RefPart &refpart, [[maybe_unused]] amrex::ParticleReal &zeval) const
Definition: RFCavity.H:392
std::tuple< amrex::ParticleReal, amrex::ParticleReal, amrex::ParticleReal > AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE RF_Efield(amrex::ParticleReal const zeval) const
Definition: RFCavity.H:338
static constexpr auto name
Definition: RFCavity.H:109
amrex::ParticleReal * m_sin_d_data
non-owning pointer to device cosine coefficients
Definition: RFCavity.H:545
ImpactXParticleContainer::ParticleType PType
Definition: RFCavity.H:110
int m_id
number of map integration steps per slice
Definition: RFCavity.H:539
amrex::ParticleReal * m_sin_h_data
non-owning pointer to host cosine coefficients
Definition: RFCavity.H:543
amrex::ParticleReal m_freq
scaling factor for RF electric field
Definition: RFCavity.H:536
int m_ncoef
unique RF cavity id used for data lookup map
Definition: RFCavity.H:541
Definition: ReferenceParticle.H:30
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE amrex::ParticleReal beta_gamma() const
Definition: ReferenceParticle.H:79
amrex::ParticleReal pt
energy, normalized by rest energy
Definition: ReferenceParticle.H:39
amrex::Array2D< amrex::ParticleReal, 1, 6, 1, 6 > map
linearized map
Definition: ReferenceParticle.H:44
amrex::ParticleReal t
clock time * c in meters
Definition: ReferenceParticle.H:35
Definition: alignment.H:27
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void shift_out(amrex::ParticleReal &AMREX_RESTRICT x, amrex::ParticleReal &AMREX_RESTRICT y, amrex::ParticleReal &AMREX_RESTRICT px, amrex::ParticleReal &AMREX_RESTRICT py) const
Definition: alignment.H:91
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE amrex::ParticleReal dx() const
Definition: alignment.H:120
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE void shift_in(amrex::ParticleReal &AMREX_RESTRICT x, amrex::ParticleReal &AMREX_RESTRICT y, amrex::ParticleReal &AMREX_RESTRICT px, amrex::ParticleReal &AMREX_RESTRICT py) const
Definition: alignment.H:61
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE amrex::ParticleReal dy() const
Definition: alignment.H:130
Definition: beamoptic.H:149
Definition: thick.H:24
Thick(amrex::ParticleReal ds, int nslice)
Definition: thick.H:30
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE amrex::ParticleReal ds() const
Definition: thick.H:53
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE int nslice() const
Definition: thick.H:43
amrex::ParticleReal m_ds
Definition: thick.H:58