Sudipta Does the oscillation frequency coincide with anything in your discretization? Is it related to your time step size or to the size of a grid cell?
What happens if you change the spatial resolution? -erik On Thu, Mar 21, 2024 at 8:28 AM Sudipta Hensh <[email protected]> wrote: > > Hi Erik, > > Sorry for the delay, I have written below the answers. > > 1. What is the size of the simulation domain? > > Simulation domain along x and y direction is [-1000,1000] and along z > direction is [0,1000]. > > 2. At which radius do you evaluate the angular momentum? > > There are two extraction radii, 200 and 300. The plot that I sent was for 300. > > 3. What is the spatial resolution there? > > Spatial resolution is 5. > > 4. What is the time resolution there? > > The time resolution is 0.75. > > 5. Is there any matter nearby? > > There is no matter during the inspiral. > > 6. What happens if you change the evaluation radius? What if you make it > smaller or larger? > > For smaller radius the amplitude of oscillations is comparatively smaller. > > 7. How close is this to the outer boundary? > > The extraction radius is far from the outer boundary. > > 8. Do you have a visualisation of the geometry (e.g. the imaginary part > of the Weyl scalar Psi_2)? > > I am afraid that I do not have Psi_2 in the output. If necessary then I can > output it. > > 9. In which direction does the angular momentum point? > Does this change over time? > > The plot I sent was for the angular momentum along z direction. > > 10. What is the magnitude of the angular momentum? How does this compare > to the mass? > > The initial magnitude of the angular momentum is 7.3 and total gravitational > mass of the system is 2.75 M_Sun. > > I am leaving below some information from the parameter file that maybe > relevant. > > CoordBase::xmin = -1000 > CoordBase::xmax = 1000 > CoordBase::ymin = -1000 > CoordBase::ymax = 1000 > CoordBase::zmin = 0 > CoordBase::zmax = 1000 > CoordBase::spacing = "numcells" > CoordBase::ncells_x = 200 > CoordBase::ncells_y = 200 > CoordBase::ncells_z = 100 > > Carpet::max_refinement_levels = 8 > Carpet::time_refinement_factors = "[1,1,2,4,8,16,32,64,128,256,512]" > > > CarpetRegrid2::num_centres = 3 > CarpetRegrid2::regrid_every = 128 > CarpetRegrid2::snap_to_coarse = "yes" > CarpetRegrid2::freeze_unaligned_levels = "yes" > CarpetRegrid2::freeze_unaligned_parent_levels = "yes" > > # ----------- Region 1 -------------------- > CarpetRegrid2::active_1 = "yes" > CarpetRegrid2::num_levels_1 = 7 > CarpetRegrid2::position_x_1 = 15.2365094091 > CarpetRegrid2::position_y_1 = 0.0 > CarpetRegrid2::radius_1[1] = 300.0 > CarpetRegrid2::radius_1[2] = 160.0 > CarpetRegrid2::radius_1[3] = 80.0 > CarpetRegrid2::radius_1[4] = 40.0 > CarpetRegrid2::radius_1[5] = 20.0 > CarpetRegrid2::radius_1[6] = 10.0 > > # ----------- Region 2 -------------------- > CarpetRegrid2::active_2 = "yes" > CarpetRegrid2::num_levels_2 = 7 > CarpetRegrid2::position_x_2 = -15.2365094091 > CarpetRegrid2::position_y_2 = -0.0 > CarpetRegrid2::radius_2[1] = 300.0 > CarpetRegrid2::radius_2[2] = 160.0 > CarpetRegrid2::radius_2[3] = 80.0 > CarpetRegrid2::radius_2[4] = 40.0 > CarpetRegrid2::radius_2[5] = 20.0 > CarpetRegrid2::radius_2[6] = 10.0 > > # ----------- Region 3 -------------------- > CarpetRegrid2::active_3 = "yes" > CarpetRegrid2::num_levels_3 = 3 > CarpetRegrid2::position_x_3 = 0 > CarpetRegrid2::radius_3[1] = 320.0 > CarpetRegrid2::radius_3[2] = 160.0 > CarpetRegrid2::radius_3[3] = 80.0 > CarpetRegrid2::radius_3[4] = 40.0 > CarpetRegrid2::radius_x_3[5] = 30.0 > CarpetRegrid2::radius_y_3[5] = 30.0 > CarpetRegrid2::radius_z_3[5] = 25.0 > CarpetRegrid2::radius_3[6] = 20.0 > CarpetRegrid2::radius_3[7] = 5.0 > # ----------------------------------------- > > Thanks for your time. I would look forward to hearing from you. > > Thanks, > Sudipta > > Sudipta Hensh > JSPS Postdoctoral Researcher > Pronouns: He/Him > Graduate School of Science > Osaka University > 1-1 Machikaneyama-cho, Toyonaka > Osaka 560-0043, Japan > > Erik Schnetter wrote: > > > Sudipta > > What is the size of the simulation domain? > At which radius do you evaluate the angular momentum? > What is the spatial resolution there? > What is the time resolution there? > Is there any matter nearby? > What happens if you change the evaluation radius? What if you make it > smaller or larger? > How close is this to the outer boundary? > Do you have a visualisation of the geometry (e.g. the imaginary part > of the Weyl scalar Psi_2)? > In which direction does the angular momentum point? > Does this change over time? > What is the magnitude of the angular momentum? How does this compare > to the mass? > > -erik > > > On Tue, Mar 19, 2024 at 9:35 AM Sudipta Hensh <[email protected]> wrote: > >> >> Dear all, >> >> I hope this email finds you well. >> >> I am performing simulations of BNS mergers and utilizing the >> QuasiLocalMeasures thorn to plot the total angular momentum of the >> spacetime. However, I have noticed high-frequency oscillations in the >> plotted data, as shown in the attached plot. I was wondering if we should >> expect such oscillations. I would also like to know the reason behind such >> oscillations. I would appreciate if you kindly help me to understand this >> issue. >> >> I am looking forward to hearing from you. Many thanks in advance! >> >> Regards, >> Sudipta Hensh >> JSPS Postdoctoral Researcher >> Pronouns: He/Him >> Graduate School of Science >> Osaka University >> 1-1 Machikaneyama-cho, Toyonaka >> Osaka 560-0043, Japan >> _______________________________________________ >> Users mailing list >> [email protected] >> > http://lists.einsteintoolkit.org/mailman/listinfo/users > > > > -- > Erik Schnetter <[email protected]> > http://www.perimeterinstitute.ca/personal/eschnetter/ > > -- Erik Schnetter <[email protected]> http://www.perimeterinstitute.ca/personal/eschnetter/ _______________________________________________ Users mailing list [email protected] http://lists.einsteintoolkit.org/mailman/listinfo/users
