Ejemplo n.º 1
0
	def __init__(self, mass, S_want, magprofile=False, omega=0., L_want=0., 
				temp_c=False, mintemp=1e5, composition="CO", togglecoulomb=True,
				S_old=False, mlt_coeff="phil", P_end_ratio=1e-8, ps_eostol=1e-8, 
				fakeouterpoint=False, stop_invertererr=True, 
				stop_mrat=2., stop_positivepgrad=True, stop_mindenserr=1e-10, 
				densest=False, omegaest=False, mass_tol=1e-6, L_tol=1e-6, 
				omega_crit_tol=1e-3, nreps=30, stopcount_max=5, 
				dontintegrate=False, verbose=True):

		# Stop doing whatever if user inserts rotation and B field
		if magprofile and omega != 0.:
			print "You cannot currently insert a magnetic field simultaneously with non-zero rotation!  Quitting."
			return

		maghydrostar_core.__init__(self, mass, temp_c, magprofile=magprofile, 
				omega=omega, L_want=L_want, mintemp=mintemp,
				composition=composition, togglecoulomb=togglecoulomb,
				fakeouterpoint=fakeouterpoint, stop_invertererr=stop_invertererr,
				stop_mrat=stop_mrat, stop_positivepgrad=stop_positivepgrad, 
				stop_mindenserr=stop_mindenserr, mass_tol=mass_tol, L_tol=L_tol, 
				omega_crit_tol=omega_crit_tol, nreps=nreps, 
				stopcount_max=stopcount_max, verbose=verbose)

		self.nablarat_crit = False			# This should only be used for debugging!

		# Initialize nuclear specific energy generation rate
		td = rtc.timescale_data(max_axes=[1e12,1e12])
		self.eps_nuc_interp = td.getinterp2d("eps_nuc")
		if S_old:
			self.populateS_old(S_old)
			if verbose:
				print "S_old defined!  Will use old entropy profile if new one dips below it."
		else:
			self.S_old = False
		self.S_old_reltol = 1e-6	# Relative tolerance to shoot for in connect_S_old

		self.derivatives = self.derivatives_steve
		self.first_deriv = self.first_derivatives_steve
		self.mlt_coeff = mlt_coeff	# Derivative and getconvection will need this for scaled Stevenson
		self.set_mlt_coeff(self.mlt_coeff)
		if self.verbose:		# self.verbose is implicitly defined in maghydrostar
			print "Stevenson 79 derivative selected!  MLT coefficient = {0:s}".format(mlt_coeff)

		if dontintegrate:
			if self.verbose:
				print "WARNING: integration disabled within mhs_steve!"
		else:
			if self.omega < 0.:
				self.omega = 0.
				self.getmaxomega(P_end_ratio=P_end_ratio, densest=densest, S_want=S_want, ps_eostol=ps_eostol)
			else:
				if L_want:
					self.getrotatingstarmodel_2d(densest=densest, omegaest=omegaest, S_want=S_want, P_end_ratio=P_end_ratio, ps_eostol=ps_eostol, damp_nrstep=0.25)
				else:
					self.getstarmodel(densest=densest, S_want=S_want, P_end_ratio=P_end_ratio, ps_eostol=ps_eostol)

		# Checks omega, just to make sure user didn't initialze a "dontintegrate" but set omega < 0
		assert self.omega >= 0.
Ejemplo n.º 2
0
def make_runaway_steve(starmass=1.2*1.9891e33, mymag=False, omega=0., omega_run_rat=0.8, S_arr=10**np.arange(7.5,8.2,0.25), 
						mlt_coeff="phil", uvs_k=3, uvs_s=None,
						mintemp=1e5, S_old=False, mass_tol=1e-6, P_end_ratio=1e-8, 
						densest=False, stop_mindenserr=1e-10, L_tol=1e-6, keepstars=False, 
						omega_crit_tol=1e-3, omega_warn=10., de_err_tol=[1e6, 1e7], verbose=True):
	"""Obtains runaway of a star of some given mass, magnetic field, and rotation.  Outputs an object (usually several hundred megs large) that includes run inputs as "run_inputs", as well as all stellar output curves (hence its size) under "stars".

	Arguments:
	starmass : wanted mass
	mymag : magnetic profile object.  Defaults to false, meaning no magnetic field.
	omega : rigid rotation angular velocity.  Defaults to 0 (non-rotating).  If < 0, attempts to estimate break-up omega with self.getomegamax(), if >= 0, uses user defined value.
	S_arr : list of central entropy values in the runaway track
	mintemp : temperature floor, effectively switches from adiabatic to isothermal profile if reached
	S_old : if True, uses the S_old function of StarModSteve to prevent entropy from decreasing below previously calculated entropy curve (which should not occur in a runaway and leads to unphysical "right hooks" in runaway rho-T diagrams).
	mlt_coeff : ["phil", "wwk", "kippw", "steve"]
		Sets mixing length theory coefficients for calculating velocity 
		and superadiabatic temperature gradients.  "phil" is the standard 
		faire coefficients suggested by Phil Chang; "wwk" is back-derived 
		from Woosley, Wunch and Kuhlen 2004; "kippw" is from 
		Kippenhahn & Wieigert (identical to Cox & Giuli); "steve" 
		is from Stevenson 1979.  Since Stevenson's rotational and magnetic
		corrections to convection are expressed as ratios of velocity and
		temperature gradient, they can be used with any of these mlt_coeffs.
	uvs_k : degree of the smoothing spline in scipy.interpolate.UnivariateSpline.
		Must be <= 5; default is k=3.
	uvs_s : UnivariateSpline positive smoothing factor used to choose the
		number of knots.  Default is None.
	mass_tol : fractional tolerance between mass wanted and mass produced by self.getstarmodel()
	P_end_ratio : ratio of P/P_c at which to terminate stellar integration
	densest : central density initial estimate for self.getstarmodel()
	stop_mindenserr : density floor, below which integration is halted.
		Default is set to 1e-10 to prevent it from ever being reached.  
		Helmholtz sometimes has trouble below this 1e-8; try adjusting this
		value to eliminate inverter errors.
	L_tol : conservation of angular momentum error tolerance
	omega_crit_tol : when using mystar.getomegamax(), absolute error tolerance for maximum omega
	omega_warn : stop integration within mystar.getrotatingstarmodel() if self.omega approaches omega_warn*omega_crit estimate.  Defaults to 10 to prevent premature stoppage.
	de_err_tol : densities at which relaxed error tolerances kick in.
	verbose : report happenings within code
	"""

	# Save a few details about the magnetic field (though we'll need better records for the actual paper)
	try:
		mymagsave = np.array([float(mymag.fBfld_r(0)), float(mymag.fBfld_r(2e8))])
	except:
		if verbose:
			print "Magnetic field not found!  Hopefully this is what you wanted."
		mymagsave = False

	r_in = {"mass": starmass, 
			"magprofile": mymagsave, 
			"omega": omega, 
			"omega_run_rat": omega_run_rat, 
			"S_arr": S_arr, 
			"mintemp": mintemp,  
			"S_old": S_old, 
			"mlt_coeff": mlt_coeff,
			"composition": "CO",
			"tog_coul": True,
			"P_end_ratio": P_end_ratio, 
			"ps_eostol": 1e-8, 
			"fakeouterpoint": False, 
			"stop_invertererr": True, 
			"stop_mrat": 2., 
			"stop_positivepgrad": True, 
			"stop_mindenserr": stop_mindenserr, 
			"densest": densest, 
			"mass_tol": mass_tol,
			"L_tol": L_tol, 
			"omega_crit_tol": omega_crit_tol, 
			"omega_warn": omega_warn,
			"lowerr_tol": de_err_tol[0],
			"mederr_tol": de_err_tol[1],
			"uvs_k": uvs_k,
			"uvs_s": uvs_s}

	if (omega != 0) or mymag:
		print "*************You want to make an MHD/rotating star; let's first try making a stationary pure hydro star!************"
		mymagzero = magprof.magprofile(None, None, None, None, blankfunc=True)
		hstar = Star.mhs_steve(r_in["mass"], False, magprofile=mymagzero, omega=0., temp_c=5e6, 
							mintemp=r_in["mintemp"], composition=r_in["composition"], togglecoulomb=r_in["tog_coul"], 
							mlt_coeff=r_in["mlt_coeff"], P_end_ratio=r_in["P_end_ratio"], 
							ps_eostol=r_in["ps_eostol"], fakeouterpoint=r_in["fakeouterpoint"], 
							stop_invertererr=r_in["stop_invertererr"], stop_mrat=r_in["stop_mrat"], 
							stop_positivepgrad=r_in["stop_positivepgrad"], stop_mindenserr=r_in["stop_mindenserr"], 
							densest=r_in["densest"], mass_tol=r_in["mass_tol"], L_tol=r_in["L_tol"], 
							omega_crit_tol=r_in["omega_crit_tol"], nreps=100, verbose=verbose)
		densest=0.9*hstar.data["rho"][0]

	print "*************Okay, let's make a low-temperature (MHD/rotating) star************"
	#Rest after this is identical to function call above
	mystar = Star.mhs_steve(r_in["mass"], False, magprofile=mymag, omega=r_in["omega"], temp_c=5e6,
							mintemp=r_in["mintemp"], composition=r_in["composition"], togglecoulomb=r_in["tog_coul"], 
							mlt_coeff=r_in["mlt_coeff"], P_end_ratio=r_in["P_end_ratio"], 
							ps_eostol=r_in["ps_eostol"], fakeouterpoint=r_in["fakeouterpoint"], 
							stop_invertererr=r_in["stop_invertererr"], stop_mrat=r_in["stop_mrat"], 
							stop_positivepgrad=r_in["stop_positivepgrad"], stop_mindenserr=r_in["stop_mindenserr"], 
							densest=r_in["densest"], mass_tol=r_in["mass_tol"], L_tol=r_in["L_tol"], 
							omega_crit_tol=r_in["omega_crit_tol"], nreps=100, verbose=verbose)

	if r_in["omega"] < 0:
		print "FOUND critical Omega = {0:.3e}!  We'll use {1:.3e} of this value for the runaway.".format(mystar.omega, r_in["omega_run_rat"])
		r_in["omega_crit_foundinfirststep"] = mystar.omega
		mystar.omega *= r_in["omega_run_rat"]

		mystar.getstarmodel(densest=0.9*mystar.data["rho"][0], P_end_ratio=r_in["P_end_ratio"], ps_eostol=r_in["ps_eostol"])

	if r_in["omega"]:
		if mystar.omega > mystar.getcritrot(max(mystar.data["M"]), mystar.data["R"][-1]):
			print "WARNING: exceeding estimated critical rotation!  Consider restarting this run."
		r_in["L_original"] = mystar.getmomentofinertia(mystar.data["R"], mystar.data["rho"])[-1]*mystar.omega
		mystar.L_want = r_in["L_original"]			# Store initial angular momentum for future use.

	out_dict = {"temp_c": np.zeros(len(S_arr)+1),
		"dens_c": np.zeros(len(S_arr)+1),
		"omega": np.zeros(len(S_arr)+1),
		"B_c": np.zeros(len(S_arr)+1),
		"S_c": np.zeros(len(S_arr)+1),
		"R": np.zeros(len(S_arr)+1),
		"stars": []}

	if "R_nuc" not in mystar.data.keys():	# Obtain timescale info if it's not already printed.
		mystar.gettimescales()

	out_dict["run_inputs"] = r_in
	if r_in["omega"] < 0:
		out_dict["omega_crit"] = r_in["omega_crit_foundinfirststep"]
	out_dict["S_c"][0] = mystar.data["Sgas"][0]
	out_dict["temp_c"][0] = mystar.data["T"][0]
	out_dict["dens_c"][0] = mystar.data["rho"][0]
	out_dict["omega"][0] = mystar.omega
	out_dict["B_c"][0] = np.mean(mystar.data["B"][:10])
	out_dict["R"][0] = mystar.data["R"][-1]
	if keepstars:
		out_dict["stars"].append(copy.deepcopy(mystar))
	else:
		out_dict["stars"].append(copy.deepcopy(mystar.data))

	# Obtain tau_cc = tau_neutrino equality line
	td = rtc.timescale_data(max_axes=[1e12,1e12])
	if r_in["S_old"]:
		ignition_line_f = td.get_tauneunuc_line()

	for i in range(len(r_in["S_arr"])):

		print "*************Star #{0:d}, entropy = {1:.3f}************".format(i, r_in["S_arr"][i])

		# If we turn on S_old and, during the previous step, we passed the ignition line, start recording old entropy profiles
		# and passing them on to the next star.
		if r_in["S_old"] and mystar.data["T"][0] > ignition_line_f(mystar.data["rho"][0]):
#			print "Using previous entropy profile"
#			if r_in["rezero_Sold"]:				# Bomb-proofing to keep extremely low entropy values from messing up integration
#				mystar.data["Sgas"][mystar.data["Sgas"] < 0.] = 0.
			myS_old = Star.sprof.entropy_profile(mystar.data["M"], mystar.data["Sgas"], mystar.data["v_conv_st"], spline_k=r_in["uvs_k"], spline_s=r_in["uvs_s"])
			mystar.S_old = myS_old.S_old
			mystar.dS_old = myS_old.dS_old
			mystar.vconv_Sold = myS_old.vconv_Sold
		outerr_code = obtain_model(mystar, i, r_in, omega_warn=r_in["omega_warn"], verbose=verbose)

		if outerr_code:
			print "===== RUNAWAY.PY REPORTS OUTERR: ", outerr_code, "for star", i, "so will stop model making! ====="
			break

		if "R_nuc" not in mystar.data.keys():	# Obtain timescale info if it's not already printed.
			mystar.getconvection(td=td)
			mystar.gettimescales()
		out_dict["S_c"][i+1] = mystar.data["Sgas"][0]
		out_dict["temp_c"][i+1] = mystar.data["T"][0]
		out_dict["dens_c"][i+1] = mystar.data["rho"][0]
		out_dict["omega"][i+1] = mystar.omega
		out_dict["B_c"][i+1] = np.mean(mystar.data["B"][:10])
		out_dict["R"][i+1] = mystar.data["R"][-1]
		if keepstars:
			out_dict["stars"].append(copy.deepcopy(mystar))
		else:
			out_dict["stars"].append(copy.deepcopy(mystar.data))

	return out_dict
Ejemplo n.º 3
0
	def getsimmermodel(self, S_want, S_old, Mconv, Lconvrat=False, densest=False, out_search=False):
		"""Obtains star at end of convective simmering, where (super-)adiabatic temperature gradient is used before user defined mass shell M_conv, and user-defined entropy profile is used after.

		Arguments:
		S_want: central entropy
		S_old: previous entropy profile
		Mconv: enclosed mass of convection zone
		densest: central density estimate (false for code to guess)
		out_search: return trial densities and corresponding masses
		"""

 		if S_old:
 			self.S_old = S_old	#Store old entropy structure
 		else:
 			self.S_old = lambda x: S_want
 
 		if Mconv:
 			self.Mconv = Mconv
 		else:
 			self.Mconv = 1e100

		if Lconvrat:
			self.Lconvrat = Lconvrat
			td = rtc.timescale_data(max_axes=[1e12,1e12])
			self.eps_nuc_interp = td.getinterp2d("eps_nuc")
		else:
			self.Lconvrat = False

		if not densest:
			densest = 3.73330253e-60*self.mass_want*self.mass_want*3.	#The 3. is recently added to reduce the time for integrating massive WDs from scratch
		stepmod = 0.1*densest

		i = 1
		[Mtot, outerr_code] = self.integrate_simmer(densest, S_want, outputerr=True)
		beforedirec = int((self.mass_want - Mtot)/abs(self.mass_want - Mtot))	#1 means next shot should have larger central density, -1 means smaller)
		stepmod = float(beforedirec)*stepmod	#Set initial direction (same notation as above)
		if self.verbose:
			print "First shot: M = {0:.5e} (vs. wanted M = {1:.5e})".format(Mtot, self.mass_want)
			print "Direction is {0:d}".format(beforedirec)

		#Minor additional test
		M_arr = np.array([Mtot])
		dens_arr = np.array([densest])
		checkglobalextreme = False

		#If we incur hugemass_err the first time
		if outerr_code == "hugemass_err":
			if self.verbose:
				print "hugemass_err is huge from the first estimate.  Let's try a much lower density."
			densest = 0.1*densest
			[Mtot, outerr_code] = self.integrate_simmer(densest, S_want, outputerr=True)

		#If we incur any error (or hugemass_err again)
		if outerr_code:
			print "OUTERR_CODE {0:s}!  EXITING FUNCTION!".format(outerr_code)
			return outerr_code

		while abs(Mtot - self.mass_want) >= self.mass_tol*self.mass_want and i < self.nreps and beforedirec != 0 and not outerr_code:

			[stepmodchange, beforedirec] = self.checkdirec(beforedirec, self.mass_want - Mtot)	#For the first time, this will give stepmodchange = 1, beforedirec = 1
			stepmod *= stepmodchange
			densest += stepmod
			if densest <= 1e1:	#Central density estimate really shouldn't be lower than about 1e4 g/cc
				densest = abs(stepmod)*0.1
				stepmod = 0.1*stepmod
			if self.verbose:
				print "Old density estimate rho = {0:.5e}; new rho = {1:.5e}".format(densest - stepmod, densest)

			[Mtot, outerr_code] = self.integrate_simmer(densest, S_want, outputerr=True)
			if self.verbose:
				print "Current shot: M = {0:.5e} (vs. wanted M = {1:.5e})".format(Mtot, self.mass_want)
			M_arr = np.append(M_arr, Mtot)
			dens_arr = np.append(dens_arr, densest)

			#Check for extreme circumstances where a solution might be impossible
			if int((dens_arr[i] - dens_arr[i-1])/abs(dens_arr[i] - dens_arr[i-1])) != int((M_arr[i] - M_arr[i-1])/abs(M_arr[i] - M_arr[i-1])) and not checkglobalextreme:
				print "Density and mass don't have a positive-definite relationship in the regime you selected!"
				if i == 1:	#Check that increasing (decreasing) central density increases (decreases) mass
					print "We're at the beginning of mass finding (i = 1), so reversing direction!"
					stepmod *= -1.0
				checkglobalextreme = True
				stopcount = 0

			#If we've already activated checkglobalextreme, we should only integrate up to stopcount = stopcount_max
			if checkglobalextreme:
				stopcount += 1
				if stopcount > self.stopcount_max:		#If we've integrated one times too many after checkglobalextreme = True
					outerr_code = self.chk_global_extrema(M_arr, Mtot - self.mass_want, self.mass_want)

			i += 1

		if beforedirec == 0:
			print "ERROR! checkdirec is printing out 0!"
		if i == self.nreps:
			print "WARNING, maximum number of shooting attempts {0:d} reached!".format(i)

		#If we incur any error (or hugemass_err again)
		if outerr_code:
			print "OUTERR_CODE {0:s}!  EXITING FUNCTION!".format(outerr_code)
			return outerr_code

		if self.verbose:
			print "Final shot!"
		Mtot = self.integrate_simmer(densest, S_want, recordstar=True)

		if abs((Mtot - self.mass_want)/self.mass_want) > self.mass_tol:
			print "ERROR!!!! (M_total - mass_want)/mass_want = {0:.5e}".format((Mtot - self.mass_want)/self.mass_want)
			print "THIS IS BIGGER THAN YOUR TOLERANCE!  CHECK YOUR ICS!"
		else:
			print "(M_total - mass_want)/mass_want = {0:.5e}".format((Mtot - self.mass_want)/self.mass_want)

		if out_search:
			return [M_arr, dens_arr]