def compton_cooling_rate(xHII, xHeII, xHeIII, T_m, rs): """Returns the Compton cooling rate. Parameters ---------- xHII : float n_HII/n_H. xHeII : float n_HeII/n_H. xHeIII : float n_HeIII/n_H. T_m : float The matter temperature. rs : float The redshift in 1+z. Returns ------- float The Compton cooling rate in eV/s. Notes ----- This is the energy loss rate, *not* the temperature loss rate. """ xe = xHII + xHeII + 2 * xHeIII return (4 * phys.thomson_xsec * 4 * phys.stefboltz / phys.me * xe * phys.nH * rs**3 * (phys.TCMB(rs) - T_m) * phys.TCMB(rs)**4)
def dyHeII_dz(yHII, yHeII, yHeIII, log_T_m, rs): T_m = np.exp(log_T_m) if not helium_TLA: return 0 if chi - xHeII(yHeII) < 1e-6 and rs < 100: # At this point, leave at 1 - 1e-6 return 0 # Stop the solver from reaching these extremes. if yHeII > 14 or yHeII < -14: return 0 # # Use the Saha values at high ionization. # if xHeII(yHeII) > 0.995*chi: # # print(phys.d_xe_Saha_dz(rs, 'HeI')) # return ( # 2/chi * np.cosh(yHeII)**2 * phys.d_xe_Saha_dz(rs, 'HeI') # ) xe = xHII(yHII) + xHeII(yHeII) + 2 * xHeIII(yHeIII) ne = xe * nH xHI = 1 - xHII(yHII) xHeI = chi - xHeII(yHeII) - xHeIII(yHeIII) term_recomb_singlet = (xHeII(yHeII) * xe * nH * phys.alpha_recomb(T_m, 'HeI_21s')) term_ion_singlet = ( phys.beta_ion(phys.TCMB(rs), 'HeI_21s') * (chi - xHeII(yHeII)) * np.exp(-phys.He_exc_eng['21s'] / phys.TCMB(rs))) term_recomb_triplet = (xHeII(yHeII) * xe * nH * phys.alpha_recomb(T_m, 'HeI_23s')) term_ion_triplet = ( 3 * phys.beta_ion(phys.TCMB(rs), 'HeI_23s') * (chi - xHeII(yHeII)) * np.exp(-phys.He_exc_eng['23s'] / phys.TCMB(rs))) return 2 / chi * np.cosh(yHeII)**2 * phys.dtdz(rs) * ( -phys.C_He(xHII(yHII), xHeII(yHeII), rs, 'singlet') * (term_recomb_singlet - term_ion_singlet) - phys.C_He(xHII(yHII), xHeII(yHeII), rs, 'triplet') * (term_recomb_triplet - term_ion_triplet) + _f_He_ion(rs, xHI, xHeI, xHeII(yHeII)) * inj_rate / (phys.He_ion_eng * nH))
def d_x_be_Saha_dz(rs, alphaD, m_be, m_bp, xi): """`z`-derivative of the Saha equilibrium ionization value. Parameters ---------- rs : float The redshift in 1+z. species : {'singlet', 'triplet'} Returns ------- float The derivative of the Saha equilibrium d xe/dz. Notes ----- See astro-ph/9909275 and 1011.3758 for details. """ x_be = x_be_Saha(rs, alphaD, m_be, m_bp, xi) T = xi * phys.TCMB(rs) B_D = get_BD(alphaD, m_be, m_bp) numer = (B_D / T - 3 / 2) * x_be**2 * (1 - x_be) denom = rs * (2 * x_be * (1 - x_be) + x_be**2) #return phys.d_xe_Saha_dz(rs, 'HI') return numer / denom
def norm_compton_cooling_rate(x_be, T_DM, rs, alphaD, m_be, m_bp, xi): """ Gamma_c where dlogT_DM/dt = Gamma_c (T_D - T_DM), in 1/s """ T_D = xi * phys.TCMB(rs) pre = 64 * np.pi**3 * alphaD**2 / 135 * T_D**4 * x_be / (1 + x_be) mass = (1 + (m_be / m_bp)**3) / m_be**3 return pre * mass / phys.hbar
def get_kappa_2s(photspec): """ Compute kappa_2s for use in kappa_DM function Parameters ---------- photspec : Spectrum object spectrum of photons. spec.toteng() should return Energy per baryon. Returns ------- kappa_2s : float The added photoionization rate from the 1s to the 2s state due to DM photons. """ # Convenient Variables eng = photspec.eng rs = photspec.rs Lambda = phys.width_2s1s_H Tcmb = phys.TCMB(rs) lya_eng = phys.lya_eng # Photon phase space density (E >> kB*T approximation) def Boltz(E): return np.exp(-E / Tcmb) bounds = spectools.get_bin_bound(eng) mid = spectools.get_indx(bounds, lya_eng / 2) # Phase Space Density of DM f_nu = photspec.dNdE * phys.c**3 / (8 * np.pi * (eng / phys.hbar)**2) # Complementary (E - h\nu) phase space density of DM f_nu_p = np.zeros(mid) # Index of point complementary to eng[k] comp_indx = spectools.get_indx(bounds, lya_eng - eng[0]) # Find the bin in which lya_eng - eng[k] resides. Store f_nu of that bin in f_nu_p. for k in np.arange(mid): while (lya_eng - eng[k]) < bounds[comp_indx]: comp_indx -= 1 f_nu_p[k] = f_nu[comp_indx] # Setting up the numerical integration # Bin sizes diffs = np.append(bounds[1:mid], lya_eng / 2) - np.insert( bounds[1:mid], 0, 0) diffs /= (2 * np.pi * phys.hbar) dLam_dnu = phys.get_dLam2s_dnu() rates = dLam_dnu(eng[:mid] / (2 * np.pi * phys.hbar)) boltz = Boltz(eng[:mid]) boltz_p = Boltz(lya_eng - eng[:mid]) # The Numerical Integral kappa_2s = np.sum(diffs * rates * (f_nu[:mid] + boltz) * (f_nu_p + boltz_p)) / phys.width_2s1s_H - Boltz(lya_eng) return kappa_2s
def Gam_pi(x_be, T_DM, rs, alphaD, m_be, m_bp, xi): B_D = get_BD(alphaD, m_be, m_bp) T_D = xi * phys.TCMB(rs) m_D = m_be + m_bp - B_D mu_D = m_be * m_bp / m_D n_D = phys.rho_DM / m_D * rs**3 denom = (3 / 2 * T_DM * n_D * (1 + x_be)) # Calculate x_2s using Hyrec's steady stateassumption # Lya_D = 3 / 4 * B_D dark_sobolev = 2**7 * alphaD**3 * B_D * n_D * phys.c**3 * (1 - x_be) / ( 3**7 * 2 * np.pi * phys.hbar * phys.hubble(rs) * Lya_D) R_D = 2**9 * alphaD**3 * B_D / 3**8 * ( 1 - np.exp(-dark_sobolev)) / dark_sobolev Lam = (alphaD / phys.alpha)**6 * (B_D / phys.rydberg) * phys.width_2s1s_H alpha_B = dark_alpha_recomb(T_DM, alphaD, m_be, m_bp, xi) beta_e = dark_beta_ion(T_D, alphaD, m_be, m_bp, xi) x_2 = (n_D * x_be**2 * alpha_B + (3 * R_D + Lam) * (1 - x_be) * np.exp(-B_D / T_D)) / (beta_e + 3 / 4 * R_D + 1 / 4 * Lam) x_2s = 1 / 4 * x_2 pre = alphaD**3 * T_D**2 / (3 * np.pi) * np.exp(-B_D / (4 * T_D)) convert = phys.hbar return pre * x_2s * n_D * F_pi(T_D / B_D) / denom * convert
def dyHII_dz(yHII, yHeII, yHeIII, log_T_m, rs): T_m = np.exp(log_T_m) if 1 - xHII(yHII) < 1e-6 and rs < 100: # At this point, leave at 1 - 1e-6 return 0 # if yHII > 14. or yHII < -14.: # # Stops the solver from wandering too far. # return 0 if xHeII(yHeII) > 0.99 * chi and rs > 1500: # This is prior to helium recombination. # Assume H completely ionized. return 0 if helium_TLA and xHII(yHII) > 0.999 and rs > 1500: # Use the Saha value. return 2 * np.cosh(yHII)**2 * phys.d_xe_Saha_dz(rs, 'HI') if not helium_TLA and xHII(yHII) > 0.99 and rs > 1500: # Use the Saha value. return 2 * np.cosh(yHII)**2 * phys.d_xe_Saha_dz(rs, 'HI') xe = xHII(yHII) + xHeII(yHeII) + 2 * xHeIII(yHeIII) ne = xe * nH xHI = 1 - xHII(yHII) xHeI = chi - xHeII(yHeII) - xHeIII(yHeIII) return 2 * np.cosh(yHII)**2 * phys.dtdz(rs) * ( # Recombination processes. # Boltzmann factor is T_r, agrees with HyREC paper. -phys.peebles_C(xHII(yHII), rs) * (phys.alpha_recomb(T_m, 'HI') * xHII(yHII) * xe * nH - 4 * phys.beta_ion(phys.TCMB(rs), 'HI') * xHI * np.exp(-phys.lya_eng / phys.TCMB(rs))) # DM injection. Note that C = 1 at late times. + _f_H_ion(rs, xHI, xHeI, xHeII(yHeII)) * inj_rate / (phys.rydberg * nH) + (1 - phys.peebles_C(xHII(yHII), rs)) * (_f_H_exc(rs, xHI, xHeI, xHeII(yHeII)) * inj_rate / (phys.lya_eng * nH)))
def Gam_pr(x_be, T_DM, rs, alphaD, m_be, m_bp, xi): B_D = get_BD(alphaD, m_be, m_bp) T_D = xi * phys.TCMB(rs) m_D = m_be + m_bp - B_D mu_D = m_be * m_bp / m_D n_D = phys.rho_DM / m_D * rs**3 denom = (3 / 2 * T_DM * n_D * (1 + x_be)) pre = 2 * alphaD**3 * np.sqrt(2 * np.pi * T_DM) / (3 * mu_D**(3 / 2)) convert = (phys.hbar * phys.c)**3 / phys.hbar return pre * x_be**2 * n_D**2 * F_pr(T_D / B_D, T_DM / T_D) / denom * convert
def Gam_R(x_be, T_DM, rs, alphaD, m_be, m_bp, xi): """ Rayleigh energy exchange rate / T_DM in 1/s """ B_D = get_BD(alphaD, m_be, m_bp) T_D = xi * phys.TCMB(rs) m_D = m_be + m_bp - B_D n_D = phys.rho_DM / m_D * rs**3 zeta_9 = 1.00201 ratio = T_D / T_DM denom = (3 / 2 * (1 + x_be)) pre = 430080 * zeta_9 * alphaD**2 * (1 - x_be) / np.pi**2 temps = (T_D / B_D)**4 * (T_D / m_be)**2 * T_D / m_D * T_D / phys.hbar return pre * temps / denom #ratio * convert
def Gam_ff(x_be, T_DM, rs, alphaD, m_be, m_bp, xi): """ free-free absorption - emission (brem) / T_DM in 1/s """ B_D = get_BD(alphaD, m_be, m_bp) T_D = xi * phys.TCMB(rs) eps = 1 - T_DM / T_D m_D = m_be + m_bp - B_D mu_D = m_be * m_bp / m_D n_D = phys.rho_DM / m_D * rs**3 g_ff = 1.33 zeta_3 = 1.20206 denom = (3 / 2 * T_DM * n_D * (1 + x_be)) pre = 16 * alphaD**3 * g_ff * x_be**2 * n_D**2 / (3 * mu_D)**(3 / 2) prnth = np.pi**2 * (1 + 2 * eps) / 6 - zeta_3 * eps convert = (phys.hbar * phys.c)**3 / phys.hbar return pre * np.sqrt(2 * np.pi * T_DM) * prnth / denom * convert
def x_be_Saha(rs, alphaD, m_be, m_bp, xi): """Saha equilibrium ionization value for H and He. Parameters ---------- rs : float The redshift in 1+z. species : {'HI', 'HeI'} The relevant species. Returns ------- float The Saha equilibrium xe. Notes ----- See astro-ph/9909275 and 1011.3758 for details. """ T = xi * phys.TCMB(rs) B_D = get_BD(alphaD, m_be, m_bp) m_D = m_be + m_bp - B_D n_D = phys.rho_DM / m_D * rs**3 #n_D = phys.nH * rs**3 mu_D = m_be * m_bp / m_D de_broglie_wavelength = phys.c * 2 * np.pi * phys.hbar / np.sqrt( 2 * np.pi * mu_D * T) rhs = (1 / de_broglie_wavelength)**3 / n_D * np.exp(-B_D / T) a = 1. b = rhs q = -rhs if rhs < 1e8: x_be = (-b + np.sqrt(b**2 - 4 * a * q)) / (2 * a) else: x_be = 1. - a / rhs return x_be
def dark_peebles_C(x_be, rs, alphaD, m_be, m_bp, xi): B_D = get_BD(alphaD, m_be, m_bp) m_D = m_be + m_bp - B_D n_D = phys.rho_DM / m_D * rs**3 #n_D = phys.nH*rs**3 T_D = xi * phys.TCMB(rs) beta = dark_beta_ion(T_D, alphaD, m_be, m_bp, xi) Lya_D = 3 / 4 * B_D dark_sobolev = 2**7 * alphaD**3 * B_D * n_D * phys.c**3 * (1 - x_be) / ( 3**7 * 2 * np.pi * phys.hbar * phys.hubble(rs) * Lya_D) R_D_fac = 3 / 4 * 2**9 * alphaD**3 * B_D / 3**8 * ( 1 - np.exp(-dark_sobolev)) / dark_sobolev Lam_2s_1s_fac = 1 / 4 * (alphaD / phys.alpha)**6 * ( B_D / phys.rydberg) * phys.width_2s1s_H ssum = R_D_fac + Lam_2s_1s_fac return ssum / (ssum + beta)
def get_elec_cooling_tf( eleceng, photeng, rs, xHII, xHeII=0, raw_thomson_tf=None, raw_rel_tf=None, raw_engloss_tf=None, coll_ion_sec_elec_specs=None, coll_exc_sec_elec_specs=None, ics_engloss_data=None, check_conservation_eng = False, verbose=False ): """Transfer functions for complete electron cooling through inverse Compton scattering (ICS) and atomic processes. Parameters ---------- eleceng : ndarray, shape (m, ) The electron kinetic energy abscissa. photeng : ndarray The photon energy abscissa. rs : float The redshift (1+z). xHII : float Ionized hydrogen fraction, nHII/nH. xHeII : float, optional Singly-ionized helium fraction, nHe+/nH. Default is 0. raw_thomson_tf : TransFuncAtRedshift, optional Thomson ICS scattered photon spectrum transfer function. If None, uses the default transfer function. Default is None. raw_rel_tf : TransFuncAtRedshift, optional Relativistic ICS scattered photon spectrum transfer function. If None, uses the default transfer function. Default is None. raw_engloss_tf : TransFuncAtRedshift, optional Thomson ICS scattered electron net energy loss transfer function. If None, uses the default transfer function. Default is None. coll_ion_sec_elec_specs : tuple of 3 ndarrays, shapes (m, m), optional Normalized collisional ionization secondary electron spectra, order HI, HeI, HeII, indexed by injected electron energy by outgoing electron energy. If None, the function calculates this. Default is None. coll_exc_sec_elec_specs : tuple of 3 ndarray, shapes (m, m), optional Normalized collisional excitation secondary electron spectra, order HI, HeI, HeII, indexed by injected electron energy by outgoing electron energy. If None, the function calculates this. Default is None. ics_engloss_data : EnglossRebinData An `EnglossRebinData` object which stores rebinning information (based on ``eleceng`` and ``photeng``) for speed. Default is None. check_conservation_eng : bool If True, lower=True, checks for energy conservation. Default is False. verbose : bool If True, prints energy conservation checks. Default is False. Returns ------- tuple Transfer functions for electron cooling deposition and spectra. See Also --------- :class:`.TransFuncAtRedshift` :class:`.EnglossRebinData` :mod:`.ics` Notes ----- The entries of the output tuple are (see Sec IIIC of the paper): 0. The secondary propagating photon transfer function :math:`\\overline{\\mathsf{T}}_\\gamma`; 1. The low-energy electron transfer function :math:`\\overline{\\mathsf{T}}_e`; 2. Energy deposited into ionization :math:`\\overline{\\mathbf{R}}_\\text{ion}`; 3. Energy deposited into excitation :math:`\\overline{\\mathbf{R}}_\\text{exc}`; 4. Energy deposited into heating :math:`\\overline{\\mathbf{R}}_\\text{heat}`; 5. Upscattered CMB photon total energy :math:`\\overline{\\mathbf{R}}_\\text{CMB}`, and 6. Numerical error away from energy conservation. Items 2--5 are vectors that when dotted into an electron spectrum with abscissa ``eleceng``, return the energy deposited/CMB energy upscattered for that spectrum. Items 0--1 are :class:`.TransFuncAtRedshift` objects. For each of these objects ``tf`` and a given electron spectrum ``elec_spec``, ``tf.sum_specs(elec_spec)`` returns the propagating photon/low-energy electron spectrum after cooling. The default version of the three ICS transfer functions that are required by this function is provided in :mod:`.tf_data`. """ # Use default ICS transfer functions if not specified. ics_tf = load_data('ics_tf') raw_thomson_tf = ics_tf['thomson'] raw_rel_tf = ics_tf['rel'] raw_engloss_tf = ics_tf['engloss'] if coll_ion_sec_elec_specs is None: # Compute the (normalized) collisional ionization spectra. coll_ion_sec_elec_specs = ( phys.coll_ion_sec_elec_spec(eleceng, eleceng, species='HI'), phys.coll_ion_sec_elec_spec(eleceng, eleceng, species='HeI'), phys.coll_ion_sec_elec_spec(eleceng, eleceng, species='HeII') ) if coll_exc_sec_elec_specs is None: # Compute the (normalized) collisional excitation spectra. id_mat = np.identity(eleceng.size) # Electron with energy eleceng produces a spectrum with one particle # of energy eleceng - phys.lya.eng. Similar for helium. coll_exc_sec_elec_tf_HI = tf.TransFuncAtRedshift( np.squeeze(id_mat[:, np.where(eleceng > phys.lya_eng)]), in_eng = eleceng, rs = -1*np.ones_like(eleceng), eng = eleceng[eleceng > phys.lya_eng] - phys.lya_eng, dlnz = -1, spec_type = 'N' ) coll_exc_sec_elec_tf_HeI = tf.TransFuncAtRedshift( np.squeeze( id_mat[:, np.where(eleceng > phys.He_exc_eng['23s'])] ), in_eng = eleceng, rs = -1*np.ones_like(eleceng), eng = ( eleceng[eleceng > phys.He_exc_eng['23s']] - phys.He_exc_eng['23s'] ), dlnz = -1, spec_type = 'N' ) coll_exc_sec_elec_tf_HeII = tf.TransFuncAtRedshift( np.squeeze(id_mat[:, np.where(eleceng > 4*phys.lya_eng)]), in_eng = eleceng, rs = -1*np.ones_like(eleceng), eng = eleceng[eleceng > 4*phys.lya_eng] - 4*phys.lya_eng, dlnz = -1, spec_type = 'N' ) # Rebin the data so that the spectra stored above now have an abscissa # of eleceng again (instead of eleceng - phys.lya_eng for HI etc.) coll_exc_sec_elec_tf_HI.rebin(eleceng) coll_exc_sec_elec_tf_HeI.rebin(eleceng) coll_exc_sec_elec_tf_HeII.rebin(eleceng) # Put them in a tuple. coll_exc_sec_elec_specs = ( coll_exc_sec_elec_tf_HI.grid_vals, coll_exc_sec_elec_tf_HeI.grid_vals, coll_exc_sec_elec_tf_HeII.grid_vals ) # Set the electron fraction. xe = xHII + xHeII # v/c of electrons beta_ele = np.sqrt(1 - 1/(1 + eleceng/phys.me)**2) ##################################### # Inverse Compton ##################################### T = phys.TCMB(rs) # Photon transfer function for single primary electron single scattering. # This is dN/(dE dt), dt = 1 s. phot_ICS_tf = ics_spec( eleceng, photeng, T, thomson_tf = raw_thomson_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot phot_ICS_tf._grid_vals = phot_ICS_tf.grid_vals.astype('float64') # Energy loss transfer function for single primary electron # single scattering. This is dN/(dE dt), dt = 1 s. engloss_ICS_tf = engloss_spec( eleceng, photeng, T, thomson_tf = raw_engloss_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot engloss_ICS_tf._grid_vals = engloss_ICS_tf.grid_vals.astype('float64') # Switch the spectra type here to type 'N'. if phot_ICS_tf.spec_type == 'dNdE': phot_ICS_tf.switch_spec_type() if engloss_ICS_tf.spec_type == 'dNdE': engloss_ICS_tf.switch_spec_type() # Define some useful lengths. N_eleceng = eleceng.size N_photeng = photeng.size # Create the secondary electron transfer functions. # ICS transfer function. elec_ICS_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) if ics_engloss_data is not None: elec_ICS_tf._grid_vals = ics_engloss_data.rebin( engloss_ICS_tf.grid_vals ) else: elec_ICS_tf._grid_vals = spectools.engloss_rebin_fast( eleceng, photeng, engloss_ICS_tf.grid_vals, eleceng ) # Total upscattered photon energy. cont_loss_ICS_vec = np.zeros_like(eleceng) # Deposited energy, enforces energy conservation. deposited_ICS_vec = np.zeros_like(eleceng) ######################### # Collisional Excitation ######################### # Collisional excitation rates. rate_vec_exc_HI = ( (1 - xHII)*phys.nH*rs**3 * phys.coll_exc_xsec(eleceng, species='HI') * beta_ele * phys.c ) rate_vec_exc_HeI = ( (phys.nHe/phys.nH - xHeII)*phys.nH*rs**3 * phys.coll_exc_xsec(eleceng, species='HeI') * beta_ele * phys.c ) rate_vec_exc_HeII = ( xHeII*phys.nH*rs**3 * phys.coll_exc_xsec(eleceng, species='HeII') * beta_ele * phys.c ) # Normalized electron spectrum after excitation. elec_exc_HI_tf = tf.TransFuncAtRedshift( rate_vec_exc_HI[:, np.newaxis]*coll_exc_sec_elec_specs[0], in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) elec_exc_HeI_tf = tf.TransFuncAtRedshift( rate_vec_exc_HeI[:, np.newaxis]*coll_exc_sec_elec_specs[1], in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) elec_exc_HeII_tf = tf.TransFuncAtRedshift( rate_vec_exc_HeII[:, np.newaxis]*coll_exc_sec_elec_specs[2], in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) # Deposited energy for excitation. deposited_exc_vec = np.zeros_like(eleceng) ######################### # Collisional Ionization ######################### # Collisional ionization rates. rate_vec_ion_HI = ( (1 - xHII)*phys.nH*rs**3 * phys.coll_ion_xsec(eleceng, species='HI') * beta_ele * phys.c ) rate_vec_ion_HeI = ( (phys.nHe/phys.nH - xHeII)*phys.nH*rs**3 * phys.coll_ion_xsec(eleceng, species='HeI') * beta_ele * phys.c ) rate_vec_ion_HeII = ( xHeII*phys.nH*rs**3 * phys.coll_ion_xsec(eleceng, species='HeII') * beta_ele * phys.c ) # Normalized secondary electron spectra after ionization. elec_spec_ion_HI = ( rate_vec_ion_HI[:,np.newaxis] * coll_ion_sec_elec_specs[0] ) elec_spec_ion_HeI = ( rate_vec_ion_HeI[:,np.newaxis] * coll_ion_sec_elec_specs[1] ) elec_spec_ion_HeII = ( rate_vec_ion_HeII[:,np.newaxis] * coll_ion_sec_elec_specs[2] ) # Construct TransFuncAtRedshift objects. elec_ion_HI_tf = tf.TransFuncAtRedshift( elec_spec_ion_HI, in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) elec_ion_HeI_tf = tf.TransFuncAtRedshift( elec_spec_ion_HeI, in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) elec_ion_HeII_tf = tf.TransFuncAtRedshift( elec_spec_ion_HeII, in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) # Deposited energy for ionization. deposited_ion_vec = np.zeros_like(eleceng) ############################################# # Heating ############################################# dE_heat_dt = phys.elec_heating_engloss_rate(eleceng, xe, rs) deposited_heat_vec = np.zeros_like(eleceng) # new_eleceng = eleceng - dE_heat_dt # if not np.all(new_eleceng[1:] > eleceng[:-1]): # utils.compare_arr([new_eleceng, eleceng]) # raise ValueError('heating loss is too large: smaller time step required.') # # After the check above, we can define the spectra by # # manually assigning slightly less than 1 particle along # # diagonal, and a small amount in the bin below. # # N_n-1 E_n-1 + N_n E_n = E_n - dE_dt # # N_n-1 + N_n = 1 # # therefore, (1 - N_n) E_n-1 - (1 - N_n) E_n = - dE_dt # # i.e. N_n = 1 + dE_dt/(E_n-1 - E_n) elec_heat_spec_grid = np.identity(eleceng.size) elec_heat_spec_grid[0,0] -= dE_heat_dt[0]/eleceng[0] elec_heat_spec_grid[1:, 1:] += np.diag( dE_heat_dt[1:]/(eleceng[:-1] - eleceng[1:]) ) elec_heat_spec_grid[1:, :-1] -= np.diag( dE_heat_dt[1:]/(eleceng[:-1] - eleceng[1:]) ) ############################################# # Initialization of secondary spectra ############################################# # Low and high energy boundaries loweng = 3000 eleceng_high = eleceng[eleceng > loweng] eleceng_high_ind = np.arange(eleceng.size)[eleceng > loweng] eleceng_low = eleceng[eleceng <= loweng] eleceng_low_ind = np.arange(eleceng.size)[eleceng <= loweng] if eleceng_low.size == 0: raise TypeError('Energy abscissa must contain a low energy bin below 3 keV.') # Empty containers for quantities. # Final secondary photon spectrum. sec_phot_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_photeng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = photeng, dlnz = -1, spec_type = 'N' ) # Final secondary low energy electron spectrum. sec_lowengelec_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) # Continuum energy loss rate per electron, dU_CMB/dt. CMB_upscatter_eng_rate = phys.thomson_xsec*phys.c*phys.CMB_eng_density(T) # Secondary scattered electron spectrum. sec_elec_spec_N_arr = ( elec_ICS_tf.grid_vals + elec_exc_HI_tf.grid_vals + elec_exc_HeI_tf.grid_vals + elec_exc_HeII_tf.grid_vals + elec_ion_HI_tf.grid_vals + elec_ion_HeI_tf.grid_vals + elec_ion_HeII_tf.grid_vals + elec_heat_spec_grid ) # Secondary photon spectrum (from ICS). sec_phot_spec_N_arr = phot_ICS_tf.grid_vals # Deposited ICS array. deposited_ICS_eng_arr = ( np.sum(elec_ICS_tf.grid_vals, axis=1)*eleceng - np.dot(elec_ICS_tf.grid_vals, eleceng) - (np.dot(sec_phot_spec_N_arr, photeng) - CMB_upscatter_eng_rate) ) # Energy loss is not taken into account for eleceng > 20*phys.me deposited_ICS_eng_arr[eleceng > 20*phys.me - phys.me] -= ( CMB_upscatter_eng_rate ) # Continuum energy loss array. continuum_engloss_arr = CMB_upscatter_eng_rate*np.ones_like(eleceng) # Energy loss is not taken into account for eleceng > 20*phys.me continuum_engloss_arr[eleceng > 20*phys.me - phys.me] = 0 # Deposited excitation array. deposited_exc_eng_arr = ( phys.lya_eng*np.sum(elec_exc_HI_tf.grid_vals, axis=1) + phys.He_exc_eng['23s']*np.sum(elec_exc_HeI_tf.grid_vals, axis=1) + 4*phys.lya_eng*np.sum(elec_exc_HeII_tf.grid_vals, axis=1) ) # Deposited ionization array. deposited_ion_eng_arr = ( phys.rydberg*np.sum(elec_ion_HI_tf.grid_vals, axis=1)/2 + phys.He_ion_eng*np.sum(elec_ion_HeI_tf.grid_vals, axis=1)/2 + 4*phys.rydberg*np.sum(elec_ion_HeII_tf.grid_vals, axis=1)/2 ) # Deposited heating array. deposited_heat_eng_arr = dE_heat_dt # Remove self-scattering, re-normalize. np.fill_diagonal(sec_elec_spec_N_arr, 0) toteng_no_self_scatter_arr = ( np.dot(sec_elec_spec_N_arr, eleceng) + np.dot(sec_phot_spec_N_arr, photeng) - continuum_engloss_arr + deposited_ICS_eng_arr + deposited_exc_eng_arr + deposited_ion_eng_arr + deposited_heat_eng_arr ) fac_arr = eleceng/toteng_no_self_scatter_arr sec_elec_spec_N_arr *= fac_arr[:, np.newaxis] sec_phot_spec_N_arr *= fac_arr[:, np.newaxis] continuum_engloss_arr *= fac_arr deposited_ICS_eng_arr *= fac_arr deposited_exc_eng_arr *= fac_arr deposited_ion_eng_arr *= fac_arr deposited_heat_eng_arr *= fac_arr # Zero out deposition/ICS processes below loweng. deposited_ICS_eng_arr[eleceng < loweng] = 0 deposited_exc_eng_arr[eleceng < loweng] = 0 deposited_ion_eng_arr[eleceng < loweng] = 0 deposited_heat_eng_arr[eleceng < loweng] = 0 continuum_engloss_arr[eleceng < loweng] = 0 sec_phot_spec_N_arr[eleceng < loweng] = 0 # Scattered low energy and high energy electrons. # Needed for final low energy electron spectra. sec_lowengelec_N_arr = np.identity(eleceng.size) sec_lowengelec_N_arr[eleceng >= loweng] = 0 sec_lowengelec_N_arr[eleceng_high_ind[0]:, :eleceng_high_ind[0]] += sec_elec_spec_N_arr[eleceng_high_ind[0]:, :eleceng_high_ind[0]] sec_highengelec_N_arr = np.zeros_like(sec_elec_spec_N_arr) sec_highengelec_N_arr[:, eleceng_high_ind[0]:] = ( sec_elec_spec_N_arr[:, eleceng_high_ind[0]:] ) # T = E.T + Prompt deposited_ICS_vec = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, deposited_ICS_eng_arr, lower=True, check_finite=False ) deposited_exc_vec = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, deposited_exc_eng_arr, lower=True, check_finite=False ) deposited_ion_vec = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, deposited_ion_eng_arr, lower=True, check_finite=False ) deposited_heat_vec = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, deposited_heat_eng_arr, lower=True, check_finite=False ) cont_loss_ICS_vec = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, continuum_engloss_arr, lower=True, check_finite=False ) sec_phot_specs = solve_triangular( np.identity(eleceng.size) - sec_elec_spec_N_arr, sec_phot_spec_N_arr, lower=True, check_finite=False ) # Prompt: low energy e produced in secondary spectrum upon scattering (sec_lowengelec_N_arr). # T : high energy e produced (sec_highengelec_N_arr). sec_lowengelec_specs = solve_triangular( np.identity(eleceng.size) - sec_highengelec_N_arr, sec_lowengelec_N_arr, lower=True, check_finite=False ) # Subtract continuum from sec_phot_specs. After this point, # sec_phot_specs will contain the *distortions* to the CMB. # Normalized CMB spectrum. norm_CMB_spec = Spectrum( photeng, phys.CMB_spec(photeng, phys.TCMB(rs)), spec_type='dNdE' ) norm_CMB_spec /= norm_CMB_spec.toteng() # Get the CMB spectrum upscattered from cont_loss_ICS_vec. upscattered_CMB_grid = np.outer(cont_loss_ICS_vec, norm_CMB_spec.N) # Subtract this spectrum from sec_phot_specs to get the final # transfer function. sec_phot_tf._grid_vals = sec_phot_specs - upscattered_CMB_grid sec_lowengelec_tf._grid_vals = sec_lowengelec_specs # Conservation checks. failed_conservation_check = False if check_conservation_eng: conservation_check = ( eleceng - np.dot(sec_lowengelec_tf.grid_vals, eleceng) # + cont_loss_ICS_vec - np.dot(sec_phot_tf.grid_vals, photeng) - deposited_exc_vec - deposited_ion_vec - deposited_heat_vec ) if np.any(np.abs(conservation_check/eleceng) > 0.1): failed_conservation_check = True if verbose or failed_conservation_check: for i,eng in enumerate(eleceng): print('***************************************************') print('rs: ', rs) print('injected energy: ', eng) print( 'Fraction of Energy in low energy electrons: ', np.dot(sec_lowengelec_tf.grid_vals[i], eleceng)/eng ) # print('Energy in photons: ', # np.dot(sec_phot_tf.grid_vals[i], photeng) # ) # print('Continuum_engloss: ', cont_loss_ICS_vec[i]) print( 'Fraction of Energy in photons - Continuum: ', ( np.dot(sec_phot_tf.grid_vals[i], photeng)/eng # - cont_loss_ICS_vec[i] ) ) print( 'Fraction Deposited in ionization: ', deposited_ion_vec[i]/eng ) print( 'Fraction Deposited in excitation: ', deposited_exc_vec[i]/eng ) print( 'Fraction Deposited in heating: ', deposited_heat_vec[i]/eng ) print( 'Energy is conserved up to (%): ', conservation_check[i]/eng*100 ) print('Fraction Deposited in ICS (Numerical Error): ', deposited_ICS_vec[i]/eng ) print( 'Energy conservation with deposited (%): ', (conservation_check[i] - deposited_ICS_vec[i])/eng*100 ) print('***************************************************') if failed_conservation_check: raise RuntimeError('Conservation of energy failed.') return ( sec_phot_tf, sec_lowengelec_tf, deposited_ion_vec, deposited_exc_vec, deposited_heat_vec, cont_loss_ICS_vec, deposited_ICS_vec )
def ics_spec( eleckineng, photeng, T, as_pairs=False, inf_upp_bound=True, thomson_tf=None, rel_tf=None, T_ref=None ): """ ICS spectrum of secondary photons. Switches between `thomson_spec` and `rel_spec`. Parameters ---------- eleckineng : ndarray Incoming electron energy. photeng : ndarray Outgoing photon energy. T : float CMB temperature. as_pairs : bool, optional If True, treats eleckineng and photeng as a paired list: produces eleckineng.size == photeng.size values. Otherwise, gets the spectrum at each photeng for each eleckineng, returning an array of length eleckineng.size*photeng.size. inf_upp_bound : bool If True, calculates the approximate relativistic spectrum that is used for fast interpolation over different values of T. See Notes for more details. Default is True. thomson_tf : TransFuncAtRedshift, optional Reference Thomson ICS transfer function. If specified, calculation is done by interpolating over the transfer function. rel_tf : TransFuncAtRedshift, optional Reference relativistic ICS transfer function. If specified, calculation is done by interpolating over the transfer function. T_ref : float, optional The reference temperature at which the reference transfer functions is evaluated. If not specified, defaults to phys.TCMB(400). Returns ------- TransFuncAtRedshift dN/(dt dE) of the outgoing photons, dt = 1 s, with `self.in_eng = eleckineng` and `self.eng = photeng`. `self.rs` is determined from `T`, and `self.dlnz` is normalized to 1 second. Notes ----- Insert note on the suitability of the method. """ if not inf_upp_bound and (thomson_tf is not None or rel_tf is not None): raise ValueError('inf_upp_bound must be True in order to use an interpolation over reference transfer functions.') gamma = eleckineng/phys.me + 1 eleceng = eleckineng + phys.me if as_pairs: if eleceng.size != photeng.size: raise TypeError('Photon and electron energy arrays must have the same length for pairwise computation.') gamma_mask = gamma eleceng_mask = eleceng eleckineng_mask = eleckineng photeng_mask = photeng spec = np.zeros(gamma) else: gamma_mask = np.outer(gamma, np.ones(photeng.size)) eleceng_mask = np.outer(eleceng, np.ones(photeng.size)) eleckineng_mask = np.outer(eleckineng, np.ones(photeng.size)) photeng_mask = np.outer(np.ones(eleceng.size), photeng) spec = np.zeros((eleceng.size, photeng.size), dtype='float128') rel_bound = 20 rel = (gamma_mask > rel_bound) if T_ref is None: T_ref = phys.TCMB(400) y = T/T_ref if rel_tf != None: if as_pairs: raise TypeError('When reading from file, the keyword as_pairs is not supported.') # If the electron energy at which interpolation is to be taken is outside rel_tf, then an error should be returned, since the file has not gone up to high enough energies. # Note relativistic spectrum is indexed by TOTAL electron energy. # rel_tf = rel_tf.at_in_eng(y*eleceng[gamma > rel_bound]) # If the photon energy at which interpolation is to be taken is outside rel_tf, then for large photon energies, we set it to zero, since the spectrum should already be zero long before. If it is below, nan is returned, and the results should not be used. rel_tf_interp = np.transpose( rel_tf.interp_func( np.log(y*eleceng[gamma > rel_bound]), np.log(y*photeng) ) ) spec[rel] = y**4*rel_tf_interp.flatten() else: spec[rel] = rel_spec( eleceng_mask[rel], photeng_mask[rel], T, inf_upp_bound=inf_upp_bound, as_pairs=True ) if thomson_tf != None: thomson_tf_interp = np.transpose( thomson_tf.interp_func( np.log(eleckineng[gamma <= rel_bound]), np.log(photeng/y) ) ) spec[~rel] = y**2*thomson_tf_interp.flatten() else: spec[~rel] = thomson_spec( eleckineng_mask[~rel], photeng_mask[~rel], T, as_pairs=True ) # Zero out spec values that are too small (clearly no scatters within the age of the universe), and numerical errors. Non-zero to take log interpolations later. spec[spec < 1e-100] = 1e-100 if as_pairs: return spec else: rs = T/phys.TCMB(1) dlnz = -1./(phys.dtdz(rs)*rs) return TransFuncAtRedshift( spec, in_eng = eleckineng, eng = photeng, rs = np.ones_like(eleckineng)*rs, dlnz=dlnz, spec_type = 'dNdE' )
def rel_spec(eleceng, photeng, T, inf_upp_bound=False, as_pairs=False): """ Relativistic ICS spectrum of secondary photons. Parameters ---------- eleceng : ndarray Incoming electron energy. photeng : ndarray Outgoing photon energy. T : float CMB temperature. inf_upp_bound : bool If True, calculates the approximate spectrum that is used for fast interpolation over different values of T. See Notes for more details. Default is False. as_pairs : bool If true, treats eleceng and photeng as a paired list: produces eleceng.size == photeng.size values. Otherwise, gets the spectrum at each photeng for each eleceng, returning an array of length eleceng.size*photeng.size. Returns ------- TransFuncAtRedshift or ndarray dN/(dt dE) of the outgoing photons (dt = 1 s). If as_pairs == False, returns a TransFuncAtRedshift, with abscissa given by (eleceng, photeng). Otherwise, returns an ndarray, with abscissa given by each pair of (eleceng, photeng). Notes ----- This function accepts the *energy* of the electron as one of the arguments and not the kinetic energy, unlike the other related ICS functions. The flag ``inf_upp_bound`` determines whether an approximation is taken that only gets the shape of the spectrum correct for :math:`E_{\\gamma,\\text{final}} \\gtrsim T_\\text{CMB}`. This is sufficient from an energy conservation perspective, and is used for building a table that can be interpolated over different values of T quickly. If ``inf_upp_bound == False``, the spectrum up to :math:`\\mathcal{O}(1/\\gamma^2)` corrections is given. This is a combination of the spectrum derived in Eq. (2.48) of Ref. [1]_ and Eq. (9) of Ref. [2]_, which assumes that electrons only lose energy, and Eq. (8) of Ref. [2]_, which contains the spectrum of photons produced electrons getting upscattered. See Also --------- :function:`.rel_spec_Jones_corr` """ print('Initializing...') gamma = eleceng/phys.me if as_pairs: if eleceng.size != photeng.size: raise TypeError('Photon and electron energy arrays must have the same length for pairwise computation.') Gamma_eps_q = ( np.divide( photeng/eleceng, 1 - photeng/eleceng, out = np.zeros_like(photeng), where = 1 - photeng/eleceng != 0 ) ) B = phys.me/(4*gamma)*Gamma_eps_q lowlim = B/T if inf_upp_bound: upplim = np.inf*np.ones_like(gamma) else: upplim = photeng/T # upplim = 4*(gamma**2)*B/T else: photeng_to_eleceng = np.outer(1/eleceng, photeng) Gamma_eps_q = ( np.divide( photeng_to_eleceng, 1 - photeng_to_eleceng, out = np.zeros_like(photeng_to_eleceng), where = 1 - photeng_to_eleceng != 0 ) ) B = np.transpose( phys.me/(4*gamma)*np.transpose(Gamma_eps_q) ) lowlim = B/T if inf_upp_bound: upplim = np.inf*np.ones_like(photeng_to_eleceng) else: upplim = np.outer(np.ones_like(eleceng), photeng)/T # upplim = np.transpose( # 4*gamma**2*np.transpose(B)/T # ) spec = np.zeros_like(Gamma_eps_q) F1_int = np.zeros_like(Gamma_eps_q) F0_int = np.zeros_like(Gamma_eps_q) F_inv_int = np.zeros_like(Gamma_eps_q) F_log_int = np.zeros_like(Gamma_eps_q) term_1 = np.zeros_like(Gamma_eps_q) term_2 = np.zeros_like(Gamma_eps_q) term_3 = np.zeros_like(Gamma_eps_q) term_4 = np.zeros_like(Gamma_eps_q) good = (lowlim > 0) Q = np.zeros_like(Gamma_eps_q) Q[good] = (1/2)*Gamma_eps_q[good]**2/(1 + Gamma_eps_q[good]) prefac = np.float128( 6*np.pi*phys.thomson_xsec*phys.c*T/(gamma**2) /(phys.ele_compton*phys.me)**3 ) print('Computing series 1/4...') F1_int[good] = F1(lowlim[good], upplim[good]) print('Computing series 2/4...') F0_int[good] = F0(lowlim[good], upplim[good]) print('Computing series 3/4...') F_inv_int[good] = F_inv(lowlim[good], upplim[good])[0] print('Computing series 4/4...') F_log_int[good] = F_log(lowlim[good], upplim[good])[0] term_1[good] = (1 + Q[good])*T*F1_int[good] term_2[good] = ( (1 + 2*np.log(B[good]/T) - Q[good])*B[good]*F0_int[good] ) term_3[good] = -2*B[good]*F_log_int[good] term_4[good] = -2*B[good]**2/T*F_inv_int[good] testing = False if testing: print('***** Diagnostics *****') print('gamma: ', gamma) print('lowlim: ', lowlim) print('lowlim*T: ', lowlim*T) print('upplim: ', upplim) print('upplim*T: ', upplim*T) print('Gamma_eps_q: ', Gamma_eps_q) print('Q: ', Q) print('B: ', B) print('***** Integrals *****') print('term_1: ', term_1) print('term_2: ', term_2) print('term_3: ', term_3) print('term_4: ', term_4) print('Sum of terms: ', term_1+term_2+term_3+term_4) print('Final answer: ', np.transpose( prefac*np.transpose( term_1 + term_2 + term_3 + term_4 ) ) ) print('***** End Diagnostics *****') print('Relativistic Computation Complete!') spec[good] = ( term_1[good] + term_2[good] + term_3[good] + term_4[good] ) spec = np.transpose(prefac*np.transpose(spec)) # Get the downscattering correction if requested. if not inf_upp_bound: downscatter_spec = rel_spec_Jones_corr( eleceng, photeng, T, as_pairs=as_pairs ) spec += downscatter_spec # Zero out spec values that are too small (clearly no scatters within the age of the universe), and numerical errors. spec[spec < 1e-100] = 0. if as_pairs: return spec else: rs = T/phys.TCMB(1) dlnz = -1./(phys.dtdz(rs)*rs) spec_arr = [ Spectrum(photeng, s, rs=rs, in_eng=in_eng) for s, in_eng in zip(spec, eleceng) ] spec_tf = TransFuncAtRedshift( spec_arr, dlnz=dlnz, in_eng = eleceng, eng = photeng, with_interp_func = True ) return spec_tf
def thomson_spec(eleckineng, photeng, T, as_pairs=False): """ Thomson ICS spectrum of secondary photons. Switches between `thomson_spec_diff` and `thomson_spec_series`. Parameters ---------- eleckineng : ndarray Incoming electron kinetic energy. photeng : ndarray Outgoing photon energy. T : float CMB temperature. as_pairs : bool If true, treats eleckineng and photeng as a paired list: produces eleckineng.size == photeng.size values. Otherwise, gets the spectrum at each photeng for each eleckineng, returning an array of length eleckineng.size*photeng.size. Returns ------- TransFuncAtRedshift or ndarray dN/(dt dE) of the outgoing photons (dt = 1 s). If as_pairs == False, returns a TransFuncAtRedshift, with abscissa given by (eleckineng, photeng). Otherwise, returns an ndarray, with abscissa given by each pair of (eleckineng, photeng). Notes ----- Insert note on the suitability of the method. """ print('Initializing...') gamma = eleckineng/phys.me + 1 # Most accurate way of finding beta when beta is small, I think. beta = np.sqrt(eleckineng/phys.me*(gamma+1)/gamma**2) eta = photeng/T # Masks, dimensions (eleckineng, photeng) if as_pairs == False. if as_pairs: if eleckineng.size != photeng.size: raise TypeError('Photon and electron energy arrays must have the same length for pairwise computation.') beta_mask = beta eta_mask = eta eleckineng_mask = eleckineng photeng_mask = photeng else: beta_mask = np.outer(beta, np.ones(eta.size)) eta_mask = np.outer(np.ones(beta.size), eta) eleckineng_mask = np.outer(eleckineng, np.ones(photeng.size)) photeng_mask = np.outer(np.ones(eleckineng.size), photeng) # Boolean arrays. Depending on as_pairs, can be 1- or 2-D. beta_small = (beta_mask < 0.01) eta_small = (eta_mask < 0.1/beta_mask) where_diff = (beta_small & eta_small) testing = False if testing: print('where_diff on (eleckineng, photeng) grid: ') print(where_diff) if as_pairs: spec = np.zeros_like(eleckineng) epsrel = np.zeros_like(eleckineng) else: spec = np.zeros((eleckineng.size, photeng.size), dtype='float128') epsrel = np.zeros((eleckineng.size, photeng.size), dtype='float128') spec[where_diff], err_with_diff = thomson_spec_diff( eleckineng_mask[where_diff], photeng_mask[where_diff], T, as_pairs=True ) epsrel[where_diff] = np.abs( np.divide( err_with_diff, spec[where_diff], out = np.zeros_like(err_with_diff), where = (spec[where_diff] != 0) ) ) if testing: print('spec from thomson_spec_diff: ') print(spec) print('epsrel from thomson_spec_diff: ') print(epsrel) where_series = (~where_diff) | (epsrel > 1e-3) if testing: print('where_series on (eleckineng, photeng) grid: ') print(where_series) spec[where_series] = thomson_spec_series( eleckineng_mask[where_series], photeng_mask[where_series], T, as_pairs=True ) if testing: spec_with_series = np.array(spec) spec_with_series[~where_series] = 0 print('spec from thomson_spec_series: ') print(spec_with_series) print('*********************') print('Final Result: ') print(spec) print('########### Spectrum computed! ###########') # Zero out spec values that are too small (clearly no scatters within the age of the universe), and numerical errors. Non-zero so that we can take log interpolations later. spec[spec < 1e-100] = 0. if as_pairs: return spec else: rs = T/phys.TCMB(1) dlnz = -1./(phys.dtdz(rs)*rs) spec_arr = [ Spectrum(photeng, s, rs=rs, in_eng=in_eng) for s, in_eng in zip(spec, eleckineng) ] # Injection energy is kinetic energy of the electron. spec_tf = TransFuncAtRedshift( spec_arr, dlnz=dlnz, in_eng = eleckineng, eng = photeng, with_interp_func = True ) return spec_tf
def engloss_spec( eleckineng, delta, T, as_pairs=False, thomson_only=False, thomson_tf=None, rel_tf=None, ): """ Thomson ICS scattered electron energy loss spectrum. Switches between :func:`.engloss_spec_series` and :func:`.engloss_spec_diff` in the Thomson regime. Also switches between Thomson and relativistic regimes automatically. Parameters ---------- eleckineng : ndarray Incoming electron kinetic energy. delta : ndarray Energy gained by photon after upscattering (only positive values). T : float CMB temperature. as_pairs : bool, optional If true, treats eleckineng and photeng as a paired list: produces eleckineng.size == photeng.size values. Otherwise, gets the spectrum at each photeng for each eleckineng, returning an array of length eleckineng.size*photeng.size. thomson_only : bool, optional If true, only returns the Thomson energy loss spectrum, and never switches to the relativistic case. thomson_tf : TransFuncAtRedshift, optional Reference Thomson energy loss ICS spectrum. If specified, calculation is done by interpolating over the transfer function. rel_tf : TransFuncAtRedshift, optional Reference relativistic energy loss ICS spectrum. If specified, calculation is done by interpolating over the transfer function. Returns ------- TransFuncAtRedshift or ndarray dN/(dt d Delta) of the outgoing photons (dt = 1 s). If as_pairs == False, returns a TransFuncAtRedshift, with abscissa given by (eleckineng, delta). Otherwise, returns an ndarray, with abscissa given by each pair of (eleckineng, delta). """ gamma = eleckineng/phys.me + 1 eleceng = eleckineng + phys.me beta = np.sqrt(eleckineng/phys.me*(gamma+1)/gamma**2) eta = delta/T # where to switch between Thomson and relativistic treatments. if thomson_only: rel_bound = np.inf else: rel_bound = 20 # 2D masks have dimensions (eleceng, delta). if as_pairs: if eleckineng.size != delta.size: raise TypeError('delta and electron energy arrays must have the same length for pairwise computation.') gamma_mask = gamma beta_mask = beta eleckineng_mask = eleckineng eleceng_mask = eleceng delta_mask = delta spec = np.zeros_like(gamma) else: gamma_mask = np.outer(gamma, np.ones_like(eta)) beta_mask = np.outer(beta, np.ones_like(eta)) eleckineng_mask = np.outer(eleckineng, np.ones_like(eta)) eleceng_mask = np.outer(eleceng, np.ones_like(eta)) delta_mask = np.outer(np.ones_like(eleckineng), delta) spec = np.zeros( (eleckineng.size, delta.size), dtype='float128' ) beta_small = beta_mask < 0.1 rel = gamma_mask > rel_bound y = T/phys.TCMB(400) if not thomson_only: if rel_tf != None: if as_pairs: raise TypeError('When reading from file, the keyword as_pairs is not supported.') # If the electron energy at which interpolation is to be taken is outside rel_tf, then an error should be returned, since the file has not gone up to high enough energies. #rel_tf = rel_tf.at_in_eng(y*eleceng[gamma > rel_bound]) # If the photon energy at which interpolation is to be taken is outside rel_tf, then for large photon energies, we set it to zero, since the spectrum should already be zero long before. If it is below, nan is returned, and the results should not be used. rel_tf_interp = np.transpose( rel_tf.interp_func( np.log(y*eleceng[gamma > rel_bound]), np.log(y*delta) ) ) spec[rel] = y**4*rel_tf_interp.flatten() else: print( '###### RELATIVISTIC ENERGY LOSS SPECTRUM ######' ) spec[rel] = ics_spectrum.rel_spec( eleceng_mask[rel], delta_mask[rel], T, inf_upp_bound=True, as_pairs=True ) print('###### COMPLETE! ######') if thomson_tf != None: thomson_tf_interp = np.transpose( thomson_tf.interp_func( np.log(eleckineng[gamma <= rel_bound]), np.log(delta/y) ) ) spec[~rel] = y**2*thomson_tf_interp.flatten() else: print('###### THOMSON ENERGY LOSS SPECTRUM ######') # beta_small obviously doesn't intersect with rel. spec[beta_small] = engloss_spec_diff( eleckineng_mask[beta_small], delta_mask[beta_small], T, as_pairs=True ) spec[~beta_small & ~rel] = engloss_spec_series( eleckineng_mask[~beta_small & ~rel], delta_mask[~beta_small & ~rel], T, as_pairs=True ) print('###### COMPLETE! ######') # Zero out spec values that are too small (clearly no scatters within the age of the universe), and numerical errors. Non-zero to take log interpolation later. spec[spec < 1e-100] = 1e-100 if as_pairs: return spec else: rs = T/phys.TCMB(1) dlnz = -1./(phys.dtdz(rs)*rs) return TransFuncAtRedshift( spec, in_eng = eleckineng, eng = delta, rs = np.ones_like(eleckineng)*rs, dlnz=dlnz, spec_type = 'dNdE', with_interp_func=True )
def get_ics_cooling_tf( raw_thomson_tf, raw_rel_tf, raw_engloss_tf, eleceng, photeng, rs, fast=True ): """Transfer function for complete electron cooling through ICS. Parameters ---------- raw_thomson_tf : TransFuncAtRedshift Raw Thomson ICS scattered photon spectrum transfer function. raw_rel_tf : TransFuncAtRedshift Raw relativistic ICS scattered photon spectrum transfer function. raw_engloss_tf : TransFuncAtRedshift Raw Thomson ICS scattered electron net energy loss spectrum transfer function. eleceng : ndarray The electron *kinetic* energy abscissa. photeng : ndarray The photon energy abscissa. rs : float The redshift (1+z). fast : bool, optional If True, uses optimized code (with very little checks) Returns ------- tuple of TransFuncAtRedshift Transfer functions for photons and low energy electrons. Notes ----- The raw transfer functions should be generated when the code package is first installed. The transfer function corresponds to the fully resolved photon spectrum after scattering by one electron. """ if fast: return get_ics_cooling_tf_fast( raw_thomson_tf, raw_rel_tf, raw_engloss_tf, eleceng, photeng, rs ) T = phys.TCMB(rs) # Photon transfer function for single primary electron single scattering. # This is dN/(dE dt), dt = 1 s. ICS_tf = ics_spec( eleceng, photeng, T, thomson_tf = raw_thomson_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot ICS_tf._grid_vals = ICS_tf.grid_vals.astype('float64') # Energy loss transfer function for single primary electron # single scattering. This is dN/(dE dt), dt = 1 s. engloss_tf = engloss_spec( eleceng, photeng, T, thomson_tf = raw_engloss_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot engloss_tf._grid_vals = engloss_tf.grid_vals.astype('float64') # Define some useful lengths. N_eleceng = eleceng.size N_photeng = photeng.size # Create the secondary electron transfer function. sec_elec_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'dNdE' ) # append_sec_elec_tf = sec_elec_tf.append # Change from energy loss spectrum to secondary electron spectrum. for i, in_eng in enumerate(eleceng): spec = engloss_tf[i] spec.engloss_rebin(in_eng, eleceng, fast=True) # Add to the appropriate row. sec_elec_tf._grid_vals[i] += spec.dNdE # Low and high energy boundaries loweng = 3000 eleceng_high = eleceng[eleceng > loweng] eleceng_high_ind = np.arange(eleceng.size)[eleceng > loweng] eleceng_low = eleceng[eleceng <= loweng] eleceng_low_ind = np.arange(eleceng.size)[eleceng <= loweng] if eleceng_low.size == 0: raise TypeError('Energy abscissa must contain a low energy bin below 3 keV.') # Empty containers for quantities. # Final secondary photon spectrum. sec_phot_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_photeng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = photeng, dlnz = -1, spec_type = 'N' ) # Final secondary low energy electron spectrum. sec_lowengelec_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) # Total upscattered photon energy. cont_loss_vec = np.zeros_like(eleceng) # Deposited energy, enforces energy conservation. deposited_vec = np.zeros_like(eleceng) # Test input electron to get the spectra. delta_spec = np.zeros_like(eleceng) # Start building sec_phot_tf and sec_lowengelec_tf. # Low energy regime first. #################################### # OLD: for loop to add identity. # # Not very clever. # #################################### # for i, eng in zip(eleceng_low_ind, eleceng_low): # # Zero out delta function test spectrum, set it correctly # # for the loop ahead. # delta_spec *= 0 # delta_spec[i] = 1 # # Add the trivial secondary electron spectrum to the # # transfer function. # sec_lowengelec_tf._grid_vals[i] += delta_spec #################################### # NEW: Just set the relevant # # part to be the identity matrix # #################################### sec_lowengelec_tf._grid_vals[:eleceng_low.size, :eleceng_low.size] = ( np.identity(eleceng_low.size) ) # Continuum energy loss rate, dU_CMB/dt. CMB_upscatter_eng_rate = phys.thomson_xsec*phys.c*phys.CMB_eng_density(T) # High energy electron loop to get fully resolved spectrum. for i, eng in zip(eleceng_high_ind, eleceng_high): # print('Check energies and indexing: ') # print(i, eleceng[i], eng) sec_phot_spec = ICS_tf[i] if sec_phot_spec.spec_type == 'dNdE': sec_phot_spec.switch_spec_type() sec_elec_spec = sec_elec_tf[i] if sec_elec_spec.spec_type == 'dNdE': sec_elec_spec.switch_spec_type() # sec_elec_spec_2 = sec_elec_tf_2[i] # if sec_elec_spec_2.spec_type == 'dNdE': # sec_elec_spec_2.switch_spec_type() # The total number of primaries scattered is equal to the total number of scattered *photons*. # The scattered electrons is obtained from the *net* energy loss, and # so is not indicative of number of scatters. tot_N_scatter = sec_phot_spec.totN() # The total energy of primary electrons which is scattered per unit time. tot_eng_scatter = tot_N_scatter*eng # The *net* total number of secondary photons produced # per unit time. sec_elec_N = sec_elec_spec.totN() # The *net* total energy of secondary electrons produced # per unit time. sec_elec_toteng = sec_elec_spec.toteng() # The total energy of secondary photons produced per unit time. sec_phot_toteng = sec_phot_spec.toteng() # Deposited energy per unit time, dD/dt. deposited_eng = sec_elec_spec.totN()*eng - sec_elec_toteng - (sec_phot_toteng - CMB_upscatter_eng_rate) print('-------- Injection Energy: ', eng) print( '-------- No. of Scatters (Analytic): ', phys.thomson_xsec*phys.c*phys.CMB_N_density(T) ) print( '-------- No. of Scatters (Computed): ', tot_N_scatter ) gamma_elec = 1 + eng/phys.me beta_elec = np.sqrt(eng/phys.me*(gamma_elec+1)/gamma_elec**2) print( '-------- Energy lost (Analytic): ', (4/3)*phys.thomson_xsec*phys.c*phys.CMB_eng_density(T)*( gamma_elec**2 * beta_elec**2 ) ) print( '-------- Energy lost (Computed from photons): ', engloss_tf[i].toteng() ) print( '-------- Energy lost (Computed from electrons): ', sec_elec_spec.totN()*eng - sec_elec_toteng ) print( '-------- Energy of upscattered photons: ', CMB_upscatter_eng_rate ) print( '-------- Energy in secondary photons (Computed): ', sec_phot_toteng ) print( '-------- Energy in secondary photons (Analytic): ', phys.thomson_xsec*phys.c*phys.CMB_eng_density(T)*( 1 + (4/3)* gamma_elec**2 * beta_elec**2 ) ) print( '-------- Energy gain from photons: ', sec_phot_toteng - CMB_upscatter_eng_rate ) print('-------- Deposited Energy: ', deposited_eng) # In the original code, the energy of the electron has gamma > 20, # then the continuum energy loss is assigned to deposited_eng instead. # I'm not sure if this is necessary, but let's be consistent with the # original code for now. continuum_engloss = CMB_upscatter_eng_rate if eng + phys.me > 20*phys.me: deposited_eng -= CMB_upscatter_eng_rate continuum_engloss = 0 # Normalize to one secondary electron. sec_phot_spec /= sec_elec_N sec_elec_spec /= sec_elec_N continuum_engloss /= sec_elec_N deposited_eng /= sec_elec_N # Remove self-scattering. selfscatter_engfrac = ( sec_elec_spec.N[i] ) scattered_engfrac = 1 - selfscatter_engfrac sec_elec_spec.N[i] = 0 sec_phot_spec /= scattered_engfrac sec_elec_spec /= scattered_engfrac continuum_engloss /= scattered_engfrac deposited_eng /= scattered_engfrac # Get the full secondary photon spectrum. Type 'N' resolved_phot_spec = sec_phot_tf.sum_specs(sec_elec_spec.N) # Get the full secondary low energy electron spectrum. Type 'N'. resolved_lowengelec_spec = ( sec_lowengelec_tf.sum_specs(sec_elec_spec.N) ) # Add the resolved spectrum to the first scatter. sec_phot_spec += resolved_phot_spec # Resolve the secondary electron continuum loss and deposition. continuum_engloss += np.dot(sec_elec_spec.N, cont_loss_vec) # utils.compare_arr([sec_elec_spec.N, deposited_vec]) deposited_eng += np.dot(sec_elec_spec.N, deposited_vec) # Now, append the resulting spectrum to the transfer function. # Do this without calling append of course: just add to the zeros # that fill the current row in _grid_vals. sec_phot_tf._grid_vals[i] += sec_phot_spec.N sec_lowengelec_tf._grid_vals[i] += resolved_lowengelec_spec.N # Set the correct values in cont_loss_vec and deposited_vec. cont_loss_vec[i] = continuum_engloss deposited_vec[i] = deposited_eng # Conservation of energy check. Check that it is 1e-10 of eng. conservation_check = ( eng - resolved_lowengelec_spec.toteng() + cont_loss_vec[i] - sec_phot_spec.toteng() ) # print('***************************************************') # print('injected energy: ', eng) # print('low energy e: ', resolved_lowengelec_spec.toteng()) # print('scattered phot: ', sec_phot_spec.toteng()) # print('continuum_engloss: ', cont_loss_vec[i]) # print('diff: ', sec_phot_spec.toteng() - cont_loss_vec[i]) # print('energy is conserved up to (%): ', conservation_check/eng*100) # print('deposited: ', deposited_vec[i]) # print( # 'energy conservation with deposited (%): ', # (conservation_check - deposited_vec[i])/eng*100 # ) # print('***************************************************') if ( conservation_check/eng > 0.01 ): print('***************************************************') print('rs: ', rs) print('injected energy: ', eng) print('low energy e: ', resolved_lowengelec_spec.toteng()) print('scattered phot: ', sec_phot_spec.toteng()) print('continuum_engloss: ', cont_loss_vec[i]) print('diff: ', sec_phot_spec.toteng() - cont_loss_vec[i]) print('energy is conserved up to (%): ', conservation_check/eng*100) print('deposited: ', deposited_vec[i]) print( 'energy conservation with deposited (%): ', (conservation_check - deposited_vec[i])/eng*100 ) print('***************************************************') raise RuntimeError('Conservation of energy failed.') # Force conservation of energy. # deposited_vec[i] += conservation_check return (sec_phot_tf, sec_lowengelec_tf, cont_loss_vec, deposited_vec)
def tla_before_reion(rs, var): # Returns an array of values for [dT_DM/dz, dy_be/dz]. # var = [T_DM, x_be] #rs = np.exp(logrs) n_D = phys.rho_DM / m_D * rs**3 #n_D = phys.nH * rs**3 #To match the SM result T_D = phys.TCMB(rs) * xi def dlogTDM_dz(y_be, log_TDM, rs): #rs = np.exp(logrs) T_DM = np.exp(log_TDM) x_be = get_x(y_be) eps = 1 - T_DM / T_D # Cooling rate due to adiabatic expansion adia = 2 / rs #Compton comp = phys.dtdz(rs) * norm_compton_cooling_rate( x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * (T_D / T_DM - 1.) #Rayleigh Rayl = phys.dtdz(rs) * Gam_R(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * (T_D / T_DM - 1) #brem heating + ion heating - recomb cooling ff_pi_pr = phys.dtdz(rs) * ( Gam_ff(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * eps + Gam_pi(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) - Gam_pr(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) - 0) deriv = Rayl + comp + adia + ff_pi_pr #Baryon-DM energy exchange V_pec = 0 fDM = 2 * x_be xsec = None #DM baryon scattering cross-section #baryon = phys.dtdz(rs) * DM_IGM_cooling_rate( # m_be, m_bp, phys.TCMB(rs), T_DM, V_pec, x_be, rs, # fDM, particle_type='DM', eps=eps #)/(3/2 * n_D * (1 + x_be)) return deriv def dybe_dz(y_be, log_T, rs): #rs = np.exp(logrs) T = np.exp(log_T) x_be = get_x(y_be) xD = 1 - x_be if x_be > 0.999 and rs > 2000: # Use the Saha value. dxdz = d_x_be_Saha_dz(rs, alphaD, m_be, m_bp, xi) return 2 * np.cosh(y_be)**2 * dxdz peeb_C = dark_peebles_C(x_be, rs, alphaD, m_be, m_bp, xi) alpha = dark_alpha_recomb(T, alphaD, m_be, m_bp, xi) beta = dark_beta_ion(T_D, alphaD, m_be, m_bp, xi) return 2 * np.cosh(y_be)**2 * phys.dtdz(rs) * ( -peeb_C * (alpha * x_be**2 * n_D - 4 * beta * xD * np.exp(-Lya_D / T_D))) nH = phys.nH * rs**3 def dlogTb_dz(yHII, log_Tb, rs): Tb = np.exp(log_Tb) xHII = get_x(yHII) xHI = 1 - xHII adia = 2 / rs denom = 3 / 2 * Tb * nH * (1 + chi + xe) comp = phys.dtdz(rs) * compton_cooling_rate(xHII, Tb, rs) / denom return adia + comp log_TDM, y_be = var[0], var[1] if both_sectors: return 0 else: return np.array( [dlogTDM_dz(y_be, log_TDM, rs), dybe_dz(y_be, log_TDM, rs)])
def get_history(rs_vec, init_cond=None, alphaD=phys.alpha, m_be=phys.me, m_bp=phys.mp, xi=1, both_sectors=False, eps=0, mxstep=1000, rtol=1e-4): """Returns the ionization and thermal history of the IGM. Parameters ---------- rs_vec : ndarray Abscissa for the solution. init_cond : array, optional Array containing [initial temperature, initial xHII, initial xHeII, initial xHeIII]. Defaults to standard values if None. mxstep : int, optional The maximum number of steps allowed for each integration point. See *scipy.integrate.odeint* for more information. rtol : float, optional The relative error of the solution. See *scipy.integrate.odeint* for more information. Returns ------- list of ndarray [temperature solution (in eV), xHII solution, xHeII, xHeIII]. Notes ----- The actual differential equation that we solve is expressed in terms of y = arctanh(f*(x - f)), where f = 0.5 for x = xHII, and f = nHe/nH * 0.5 for x = xHeII or xHeIII, where nHe/nH is approximately 0.083. """ B_D = get_BD(alphaD, m_be, m_bp) m_D = m_be + m_bp - B_D Lya_D = 3 / 4 * B_D # Define conversion functions between x and y. def get_x(y): return 0.5 + 0.5 * np.tanh(y) def tla_before_reion(rs, var): # Returns an array of values for [dT_DM/dz, dy_be/dz]. # var = [T_DM, x_be] #rs = np.exp(logrs) n_D = phys.rho_DM / m_D * rs**3 #n_D = phys.nH * rs**3 #To match the SM result T_D = phys.TCMB(rs) * xi def dlogTDM_dz(y_be, log_TDM, rs): #rs = np.exp(logrs) T_DM = np.exp(log_TDM) x_be = get_x(y_be) eps = 1 - T_DM / T_D # Cooling rate due to adiabatic expansion adia = 2 / rs #Compton comp = phys.dtdz(rs) * norm_compton_cooling_rate( x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * (T_D / T_DM - 1.) #Rayleigh Rayl = phys.dtdz(rs) * Gam_R(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * (T_D / T_DM - 1) #brem heating + ion heating - recomb cooling ff_pi_pr = phys.dtdz(rs) * ( Gam_ff(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) * eps + Gam_pi(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) - Gam_pr(x_be, T_DM, rs, alphaD, m_be, m_bp, xi) - 0) deriv = Rayl + comp + adia + ff_pi_pr #Baryon-DM energy exchange V_pec = 0 fDM = 2 * x_be xsec = None #DM baryon scattering cross-section #baryon = phys.dtdz(rs) * DM_IGM_cooling_rate( # m_be, m_bp, phys.TCMB(rs), T_DM, V_pec, x_be, rs, # fDM, particle_type='DM', eps=eps #)/(3/2 * n_D * (1 + x_be)) return deriv def dybe_dz(y_be, log_T, rs): #rs = np.exp(logrs) T = np.exp(log_T) x_be = get_x(y_be) xD = 1 - x_be if x_be > 0.999 and rs > 2000: # Use the Saha value. dxdz = d_x_be_Saha_dz(rs, alphaD, m_be, m_bp, xi) return 2 * np.cosh(y_be)**2 * dxdz peeb_C = dark_peebles_C(x_be, rs, alphaD, m_be, m_bp, xi) alpha = dark_alpha_recomb(T, alphaD, m_be, m_bp, xi) beta = dark_beta_ion(T_D, alphaD, m_be, m_bp, xi) return 2 * np.cosh(y_be)**2 * phys.dtdz(rs) * ( -peeb_C * (alpha * x_be**2 * n_D - 4 * beta * xD * np.exp(-Lya_D / T_D))) nH = phys.nH * rs**3 def dlogTb_dz(yHII, log_Tb, rs): Tb = np.exp(log_Tb) xHII = get_x(yHII) xHI = 1 - xHII adia = 2 / rs denom = 3 / 2 * Tb * nH * (1 + chi + xe) comp = phys.dtdz(rs) * compton_cooling_rate(xHII, Tb, rs) / denom return adia + comp log_TDM, y_be = var[0], var[1] if both_sectors: return 0 else: return np.array( [dlogTDM_dz(y_be, log_TDM, rs), dybe_dz(y_be, log_TDM, rs)]) if init_cond is None: #rs_start = np.exp(logrs_vec[0]) rs_start = rs_vec[0] x_Saha = x_be_Saha(rs_start, alphaD, m_be, m_bp, xi) _init_cond = [xi * phys.TCMB(rs_start), x_Saha] else: _init_cond = np.array(init_cond) if init_cond[1] == 1: _init_cond[1] = 1 - 1e-12 _init_cond[0] = np.log(_init_cond[0]) _init_cond[1] = np.arctanh(2 * (_init_cond[1] - 0.5)) _init_cond = np.array(_init_cond) # Note: no reionization model implemented. soln = odeint(tla_before_reion, _init_cond, rs_vec, mxstep=mxstep, tfirst=True, rtol=rtol) #soln = rk( # tla_before_reion, _init_cond, # rs_vec[0], rs_vec[10], step=-.01, vec=None, # rtol=1e-2 #) # Convert from log_T_m to T_m soln[:, 0] = np.exp(soln[:, 0]) soln[:, 1] = 0.5 + 0.5 * np.tanh(soln[:, 1]) return soln
def get_ics_cooling_tf_fast( raw_thomson_tf, raw_rel_tf, raw_engloss_tf, eleceng, photeng, rs ): """ Transfer function for complete electron cooling through ICS. Parameters ---------- raw_thomson_tf : TransFuncAtRedshift Raw Thomson ICS scattered photon spectrum transfer function. raw_rel_tf : TransFuncAtRedshift Raw relativistic ICS scattered photon spectrum transfer function. raw_engloss_tf : TransFuncAtRedshift Raw Thomson ICS scattered electron net energy loss spectrum transfer function. eleceng : ndarray The electron *kinetic* energy abscissa. photeng : ndarray The photon energy abscissa. rs : float The redshift (1+z). Returns ------- tuple of TransFuncAtRedshift Transfer functions for photons and low energy electrons. Notes ----- The raw transfer functions should be generated when the code package is first installed. The transfer function corresponds to the fully resolved photon spectrum after scattering by one electron. This version of the code works faster, but dispenses with energy conservation checks and several other safeguards. Use only with default abscissa, or when get_ics_cooling_tf works. """ T = phys.TCMB(rs) # Photon transfer function for single primary electron single scattering. # This is dN/(dE dt), dt = 1 s. ICS_tf = ics_spec( eleceng, photeng, T, thomson_tf = raw_thomson_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot ICS_tf._grid_vals = ICS_tf.grid_vals.astype('float64') # Energy loss transfer function for single primary electron # single scattering. This is dN/(dE dt), dt = 1 s. engloss_tf = engloss_spec( eleceng, photeng, T, thomson_tf = raw_engloss_tf, rel_tf = raw_rel_tf ) # Downcasting speeds up np.dot engloss_tf._grid_vals = engloss_tf.grid_vals.astype('float64') # Switch the spectra type here to type 'N'. if ICS_tf.spec_type == 'dNdE': ICS_tf.switch_spec_type() if engloss_tf.spec_type == 'dNdE': engloss_tf.switch_spec_type() # Define some useful lengths. N_eleceng = eleceng.size N_photeng = photeng.size # Create the secondary electron transfer function. sec_elec_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) sec_elec_tf._grid_vals = spectools.engloss_rebin_fast( eleceng, photeng, engloss_tf.grid_vals, eleceng ) # Change from energy loss spectrum to secondary electron spectrum. # for i, in_eng in enumerate(eleceng): # spec = engloss_tf[i] # spec.engloss_rebin( # in_eng, eleceng, out_spec_type='N', fast=True # ) # # Add to the appropriate row. # sec_elec_tf._grid_vals[i] += spec.N # Low and high energy boundaries loweng = 3000 eleceng_high = eleceng[eleceng > loweng] eleceng_high_ind = np.arange(eleceng.size)[eleceng > loweng] eleceng_low = eleceng[eleceng <= loweng] eleceng_low_ind = np.arange(eleceng.size)[eleceng <= loweng] if eleceng_low.size == 0: raise TypeError('Energy abscissa must contain a low energy bin below 3 keV.') # Empty containers for quantities. # Final secondary photon spectrum. sec_phot_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_photeng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = photeng, dlnz = -1, spec_type = 'N' ) # Final secondary low energy electron spectrum. sec_lowengelec_tf = tf.TransFuncAtRedshift( np.zeros((N_eleceng, N_eleceng)), in_eng = eleceng, rs = rs*np.ones_like(eleceng), eng = eleceng, dlnz = -1, spec_type = 'N' ) # Total upscattered photon energy. cont_loss_vec = np.zeros_like(eleceng) # Deposited energy, enforces energy conservation. deposited_vec = np.zeros_like(eleceng) # Test input electron to get the spectra. delta_spec = np.zeros_like(eleceng) # Start building sec_phot_tf and sec_lowengelec_tf. # Low energy regime first. sec_lowengelec_tf._grid_vals[:eleceng_low.size, :eleceng_low.size] = ( np.identity(eleceng_low.size) ) # Continuum energy loss rate, dU_CMB/dt. CMB_upscatter_eng_rate = phys.thomson_xsec*phys.c*phys.CMB_eng_density(T) # High energy electron loop to get fully resolved spectrum. for i, eng in zip(eleceng_high_ind, eleceng_high): # print('Check energies and indexing: ') # print(i, eleceng[i], eng) sec_phot_spec_N = ICS_tf._grid_vals[i] sec_elec_spec_N = sec_elec_tf._grid_vals[i] # The total number of primaries scattered is equal to the total number of scattered *photons*. # The scattered electrons is obtained from the *net* energy loss, and # so is not indicative of number of scatters. tot_N_scatter = np.sum(sec_phot_spec_N) # The total energy of primary electrons which is scattered per unit time. tot_eng_scatter = tot_N_scatter*eng # The *net* total number of secondary photons produced # per unit time. sec_elec_totN = np.sum(sec_elec_spec_N) # The *net* total energy of secondary electrons produced # per unit time. sec_elec_toteng = np.dot(sec_elec_spec_N, eleceng) # The total energy of secondary photons produced per unit time. sec_phot_toteng = np.dot(sec_phot_spec_N, photeng) # Deposited energy per unit time, dD/dt. # Numerical error (should be zero except for numerics) deposited_eng = sec_elec_totN*eng - sec_elec_toteng - (sec_phot_toteng - CMB_upscatter_eng_rate) diagnostics = False if diagnostics: print('-------- Injection Energy: ', eng) print( '-------- No. of Scatters (Analytic): ', phys.thomson_xsec*phys.c*phys.CMB_N_density(T) ) print( '-------- No. of Scatters (Computed): ', tot_N_scatter ) gamma_elec = 1 + eng/phys.me beta_elec = np.sqrt(eng/phys.me*(gamma_elec+1)/gamma_elec**2) print( '-------- Energy lost (Analytic): ', (4/3)*phys.thomson_xsec*phys.c*phys.CMB_eng_density(T)*( gamma_elec**2 * beta_elec**2 ) ) print( '-------- Energy lost (Computed from photons): ', engloss_tf[i].toteng() ) print( '-------- Energy lost (Computed from electrons): ', sec_elec_totN*eng - sec_elec_toteng ) print( '-------- Energy of upscattered photons: ', CMB_upscatter_eng_rate ) print( '-------- Energy in secondary photons (Computed): ', sec_phot_toteng ) print( '-------- Energy in secondary photons (Analytic): ', phys.thomson_xsec*phys.c*phys.CMB_eng_density(T)*( 1 + (4/3)* gamma_elec**2 * beta_elec**2 ) ) print( '-------- Energy gain from photons: ', sec_phot_toteng - CMB_upscatter_eng_rate ) print('-------- Deposited Energy: ', deposited_eng) # In the original code, the energy of the electron has gamma > 20, # then the continuum energy loss is assigned to deposited_eng instead. # I'm not sure if this is necessary, but let's be consistent with the # original code for now. continuum_engloss = CMB_upscatter_eng_rate if eng + phys.me > 20*phys.me: deposited_eng += CMB_upscatter_eng_rate continuum_engloss = 0 # Normalize to one secondary electron. sec_phot_spec_N /= sec_elec_totN sec_elec_spec_N /= sec_elec_totN continuum_engloss /= sec_elec_totN deposited_eng /= sec_elec_totN # Remove self-scattering. selfscatter_engfrac = ( sec_elec_spec_N[i] ) scattered_engfrac = 1 - selfscatter_engfrac sec_elec_spec_N[i] = 0 sec_phot_spec_N /= scattered_engfrac sec_elec_spec_N /= scattered_engfrac continuum_engloss /= scattered_engfrac deposited_eng /= scattered_engfrac # Get the full secondary photon spectrum. Type 'N' resolved_phot_spec_vals = np.dot( sec_elec_spec_N, sec_phot_tf._grid_vals ) # Get the full secondary low energy electron spectrum. Type 'N'. # resolved_lowengelec_spec_vals = np.dot( # sec_elec_spec_N, sec_lowengelec_tf._grid_vals # ) # The resolved lowengelec spectrum is simply one electron # in the bin just below 3 keV. # Added directly to sec_lowengelec_tf. Removed the dot for speed. # resolved_lowengelec_spec_vals = np.zeros_like(eleceng) # resolved_lowengelec_spec_vals[eleceng_low_ind[-1]] += 1 # Add the resolved spectrum to the first scatter. sec_phot_spec_N += resolved_phot_spec_vals # Resolve the secondary electron continuum loss and deposition. continuum_engloss += np.dot(sec_elec_spec_N, cont_loss_vec) deposited_eng += np.dot(sec_elec_spec_N, deposited_vec) # Now, append the resulting spectrum to the transfer function. # Do this without calling append of course: just add to the zeros # that fill the current row in _grid_vals. sec_phot_tf._grid_vals[i] += sec_phot_spec_N sec_lowengelec_tf._grid_vals[i, eleceng_low_ind[-1]] += 1 # Set the correct values in cont_loss_vec and deposited_vec. cont_loss_vec[i] = continuum_engloss deposited_vec[i] = deposited_eng check = False if check: conservation_check = ( eng - np.dot(resolved_lowengelec_spec_vals, eleceng) + cont_loss_vec[i] - np.dot(sec_phot_spec_N, photeng) ) if ( conservation_check/eng > 0.01 ): print('***************************************************') print('rs: ', rs) print('injected energy: ', eng) print( 'low energy e: ', np.dot(resolved_lowengelec_spec_vals, eleceng) ) print('scattered phot: ', np.dot(sec_phot_spec_N, photeng)) print('continuum_engloss: ', cont_loss_vec[i]) print( 'diff: ', np.dot(sec_phot_spec_N, photeng) - cont_loss_vec[i] ) print( 'energy is conserved up to (%): ', conservation_check/eng*100 ) print('deposited: ', deposited_vec[i]) print( 'energy conservation with deposited (%): ', (conservation_check - deposited_vec[i])/eng*100 ) print('***************************************************') raise RuntimeError('Conservation of energy failed.') return (sec_phot_tf, sec_lowengelec_tf, cont_loss_vec, deposited_vec)
def compton_cooling_rate(xHII, T_m, rs): """SM Compton cooling rate. dE/dVdt""" ne = xHII * phys.nH * rs**3 pre = 4 * phys.thomson_xsec * 4 * phys.stefboltz / phys.me return pre * (phys.TCMB(rs) - T_m) * phys.TCMB(rs)**4