Subject: Re: xray line profiles From: luc@as.arizona.edu Date: Tue, 5 Jun 2007 14:23:46 -0700 (MST) To: "David Cohen" CC: "Stan Owocki" , "Townsend Rich" , "Leutenegger Maurice" , "Fullerton Alex" David, All is going well here, thanks! Feel free to use the X-ray line profiles I computed from the 2D LDI simulations. These are not computed analytically so bumps and wiggles just stem from the relatively low resolution (constant delta_r/r, which makes it worse for cases in which R_0 is large) for the computation. In particular, the emissivity switches on suddenly and so, when stepping along a ray, this can cause slight problems. Increasing the number of depth points gets rid of these wiggles (see attached file). All the best, Luc > > I will be mostly talking about the constraints imposed by x-ray > > spectra. One type of constraint we can derive from the data is that if > > porosity is indeed symmetrizing the x-ray line profiles, then porosity > > lengths must be big (> 1 Rstar). I will show some hydro output snapshots > > from your 2003 and 2005 papers with Stan, but I'd also like to show the > > line profiles you synthesized from these simulations (shown in the > > above-quoted figure). Please let me know if this would be OK. And if > > so, I have a specific question about the figure: The dot-dash blue > > lines are the profiles synthesized from your simulation's wind > > structure, but my interpretation of your description in your email below > > is that the black lines represent smooth-wind profiles. However, the > > black lines in your plots are in some cases a bit bumpy, and I was > > wondering why that is. Were they perhaps calculated using Monte Carlo > > techniques? > > > > Thanks in advance for your responses on this matter. > > > > David > > > > > > Stan Owocki wrote: >> >> Luc, >> >> >> >> Thanks for doing this so quickly. It's nice to have explicit >> >> confirmation of this argument that the structure in our 2D sims of the >> >> LDI is too small to have much porosity effect on the line profiles. >> >> >> >> David Cohen and others are coming up for a day of discussion tomorrow, >> >> and so we may have some further feedback and/or questions on your >> >> calculation. >> >> >> >> Regards, >> >> Stan >> >> >> >> On May 21, 2006, at 9:47 PM, luc@as.arizona.edu wrote: >> >> >>> >>> Hello Stan, >>> >>> >>> >>> I have computed the X-ray line profiles following the OC paper and >>> >>> using the hydro sims from >>> >>> the 2003 letter. I have put two figures on >>> >>> hermes.as.arizona.edu/~luc/stan >>> >>> for cases with >>> >>> q=0 and q=3. There are different panels for different R0 values, and in >>> >>> each panel three curves >>> >>> for different tau_star values. In practice, my tau_star scaling is >>> >>> analogous but different from you tau_star since I work with the rho >>> >>> from >>> >>> the hydro sims. However, the three curves would ressemble what you have >>> >>> for tau_star=1,2, and 5. >>> >>> >>> >>> For each case, there are two curves: the solid line corresponds to >>> >>> the >>> >>> spherically symmetric and >>> >>> SMOOTH case, and the broken line corresponds to the 2D structured >>> >>> wind. In >>> >>> this case, I >>> >>> mapped one hydro input (12deg wedge) 9 times to cover along a direction >>> >>> phi (cylindrical coord >>> >>> p,phi,z, with the observer along z), the plane with theta = 0 to 180 >>> >>> deg >>> >>> (angle to the line of sight) and p=0 to 10Rstar (remember that our >>> >>> hydro >>> >>> sims do not extend to vinf, which means that in >>> >>> these profiles, emission extends at most up to 90% vinf). When >>> >>> compuuting >>> >>> the total profile, I multiply by 2pi, i.e. I actually do not use >>> >>> different >>> >>> 2D hydro inputs in other phi angles to do >>> >>> the integral in this direction as well since, as you can see, the >>> >>> effect >>> >>> is really small. >>> >>> >>> >>> I tried to plot things the way you did in OC so you should find >>> >>> these >>> >>> plots familiar. Bottom line, >>> >>> using the structured outflow changes very modestly the line profiles, >>> >>> although it introduces >>> >>> some fine structure in the profiles. The skewness is not changed, nor >>> >>> the >>> >>> relative flux between >>> >>> line center and wing. As expected, not much porosity in our sims. >>> >>> >>> >>> Let me know your thoughts on this initial attempt. >>> >>> Thanks, >>> >>> >>> >>> Luc > xray_porous_q0_dz3em4_np520.ps Content-Type: application/postscript Content-Encoding: base64