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</style><p>Dear David,</p><p><br></p><p>Thank you for your very detailed explanation.</p><p>I followed your instructions and was able to get the results I wanted.</p><p>By defining the bin width very small, you mean that there is only a primary x-ray there, right?</p><p>And when the bin width is quite coarse , the coordinates of (0,0) include primary and some scatter rays (Compton scattering).</p><p>Then, by subtracting the direct ray count obtained from the (0, 0) coordinates, it is possible to calculate the scattered ray count at (0, 0) when the bin width is coarse.</p><p><br></p><p>Thank you very much!</p><p>mas</p><p><br></p><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">----- Original Message -----</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><br></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>From: </strong>"David Leibold" <D.Leibold@tudelft.nl></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>To: </strong>"mas" <fight1_fight2@yahoo.co.jp></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Cc: </strong>"gate-users@lists.opengatecollaboration.org" <gate-users@lists.opengatecollaboration.org></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Date: </strong>2022/09/05 月 18:00</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Subject: </strong>RE: RE: Re: [Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><br></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><br></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Dear mas,</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">If we talk about discretized pixels/bins, then I agree: the bin size of the histogram that I chose in the example is quite coarse (depending, of course, on the source-detector-distance), so I agree that it might happen that scattered rays still end up in the centre bin.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Now let’s consider the actual intersection point of an X-ray with the detector plane, so before binning:</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">- In case of Compton scattering, the conservation of impulse dictates that the scattered photon ends up outside (0,0). </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">- In case of Rayleigh scattering, it is (I think) possible that the scattered photon ends up in (0,0) as well, but since Rayleigh scattering conserves the energy of the photon, a “Rayleigh scattered photon without change in direction” is indistinguishable from a “primary photon”. (By the way, Rayleigh scatter can usually be neglected in the energy range of diagnostic X-ray energies.)</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Coming back to the problem that a coarse pixel grid might include scatter in the centre pixel: You can then either choose a very fine pixel grid, or define your bins such that there is one very small bin around the centre (0,0) and then a large bin for the rest.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">To get a feeling for what is a good pixel/bin size, you can for example plot a histogram of the distance between the intersection point of a photon with the detector and the origin. Choose a very fine grid for the histogram. If you histogram bin size is small enough, you will then see that there is a small area around the origin without any counts in your histogram.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">I hope this answers your questions, if not, let me know!</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Best regards,</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">David</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>From:</strong> mas <fight1_fight2@yahoo.co.jp> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> <strong>Sent:</strong> Monday, 5 September 2022 9:45 AM</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> <strong>To:</strong> David Leibold <D.Leibold@tudelft.nl></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> <strong>Cc:</strong> gate-users@lists.opengatecollaboration.org</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> <strong>Subject:</strong> Re: RE: Re: [Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Dear David,</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Thank you for your very detailed explanation. And thank you for teaching me how to open root in python.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">This was very helpful!</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">I tried as you told me. Then I extracted the primary and scatter x-ray data from ”phaseSpace.root".</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">However, one question remained.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">It was assumed that the point hit by the pencil beam (eg P(0,0)) is only primary x-ray.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">However, in actually, I think that scattered rays with small scattering angles also enter (0,0).</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">As a result, the point in (x,y)=(0,0) will sum of the primary and scatter. (eg P(0,0)+S(0,0))</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">In such a case, does it mean that primary and scatter cannot be separated in the phase space actor?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">I also want to get the scatter component at coordinates (0,0).</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">I'm sorry if my thinking is wrong.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Thank you</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">mas</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">----- Original Message -----</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>From: </strong>"David Leibold" <<a href="mailto:D.Leibold@tudelft.nl" target="_blank">D.Leibold@tudelft.nl</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>To: </strong>"mas" <<a href="mailto:fight1_fight2@yahoo.co.jp" target="_blank">fight1_fight2@yahoo.co.jp</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Cc: </strong>"<a href="mailto:gate-users@lists.opengatecollaboration.org" target="_blank">gate-users@lists.opengatecollaboration.org</a>" <<a href="mailto:gate-users@lists.opengatecollaboration.org" target="_blank">gate-users@lists.opengatecollaboration.org</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Date: </strong>2022/09/02 金 16:07</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Subject: </strong>RE: Re: [Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Dear Mas,</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">You mention that you got a one-dimensional profile, and you show a screenshot of the root output. However, please note that you select only the x-coordinates of the root output, that means, you select the x-coordinate of all particles intersecting your detector plane. Since you select only one variable, you will obtain a one-dimensional output. </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">The phase space actor does not have a built-in function that separates scatter and primaries; you have to do this yourself.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">What you have to do is the following (and I hope that also answers your questions 2-3 as well): You have to extract the (x,y) coordinates for all events, and then filter the events based on their distance to the centre of the detector. (I assume that the centre of the detector is the point at which the pencil beam is directed.) To be honest, I have never really used the root object browser, so others might share more light on this. For my data analysis I use Python. There is a Python library called “</span><a style="color:black" href="https://urldefense.com/v3/__https:/uproot.readthedocs.io/en/latest/__;!!PAKc-5URQlI!4TACOtbbEWaSmINTkHUyQlT5ut0PBTLOoLSOiu362wQGtm8P0OPqzNqcB5JU8UtZY2ovvrMSeogoJOQDJq8PAEzFh4tM0w$" target="_blank">uproot</a><span style="color:black">”, which enables you to read the root files.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Here's some example code to read the root file that is output by the phase space actor; in this example the file is called “phaseSpace.root”.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">import numpy as np</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">import uproot</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">import matplotlib.pyplot as plt</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"># Load the root file:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">with uproot.open("phaseSpace.root") as rootfile:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> data = rootfile['PhaseSpace'].arrays(filter_name="*", library='np’)</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # root files have a tree structure, like a trunk with many branches.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # The “trunk” of a root file that is output by a phase space actor</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # is called ‘PhaseSpace’. With the function ‘arrays’ we can</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # access all the branches that we want. You can specify the</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # desired branches with the argument ‘filter_name’. If you use the</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # wildcard ‘*’, then all branches are loaded. If you just want the</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # x and y coordinate, you can do</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # filter_name = [‘X’, ‘Y’]</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # . The argument ‘library’ specifies whether you want to use numpy</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # or pandas. The former is better in terms of performance, the</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # latter is nicer for visualisation.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"># Create a 2D histogram:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">xbins = np.arange(-240, 241, 1)</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">ybins = np.arange(-240, 241, 1)</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">histData, histXbins, histYbins = np.histogram2d(data['X'], data['Y'], bins=[xbins, ybins])</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"># Plot the result:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">fig, ax = plt.subplots()</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">ax.imshow(histData, vmin=0, vmax=2)</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # Please note that the origin of the plot does not coincide with the</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> # data origin, you would have to shift that manually</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><img width="675" src="cid:gAfiBfs9ITIuPy6eZvvJ"></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">(That little dot in the centre of the figure is not dust on your screen, it’s actually a very faint signal…)</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Based the 2D histogram, you can now say that all events that are outside, for example, a 0.1 mm region around the origin, are scatter.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">I hope that helps! If you need more help, let me know.</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">Best regards,</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">David</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black">PS: Sorry for writing your name incorrectly in my last mail!</span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><span style="color:black"> </span></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>From:</strong> mas <<a href="mailto:fight1_fight2@yahoo.co.jp" target="_blank">fight1_fight2@yahoo.co.jp</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Sent:</strong> Friday, 2 September 2022 8:27 AM</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>To:</strong> David Leibold <<a href="mailto:D.Leibold@tudelft.nl" target="_blank">D.Leibold@tudelft.nl</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Cc:</strong> <a href="mailto:gate-users@lists.opengatecollaboration.org" target="_blank"> gate-users@lists.opengatecollaboration.org</a></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Subject:</strong> Re: Re: [Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Dear David,</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Thanks to your reply, I understood that I should use the phase space actor.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">After reading the documentation, I tried using phase space actor.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">I got a one-dimensional profile.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">It was certainly like a point spread function.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">However, some questions remained.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">1)The output is a one-dimensional profile, but how do I know which location on the detector is profiled?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">2)Which function of the phase space actor is used to separate scattered and direct lines?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">[/gate/actor/MyActor/storeOutgoingParticles true] is used?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">3)How do I output the actual values from the root file, e.g. a txt file? I am sorry that this is not the original question.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Thank you.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">mas</blockquote><pre> </pre><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">----- Original Message -----</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>From: </strong>"David Leibold" <<a href="mailto:D.Leibold@tudelft.nl" target="_blank">D.Leibold@tudelft.nl</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>To: </strong>"mas" <<a href="mailto:fight1_fight2@yahoo.co.jp" target="_blank">fight1_fight2@yahoo.co.jp</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Cc: </strong>"<a href="mailto:gate-users@lists.opengatecollaboration.org" target="_blank">gate-users@lists.opengatecollaboration.org</a>" <<a href="mailto:gate-users@lists.opengatecollaboration.org" target="_blank">gate-users@lists.opengatecollaboration.org</a>></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Date: </strong>2022/09/02 金 00:35</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><strong>Subject: </strong>Re: [Gate-users] How to measure the X-rays scattered by the phantom when they enter the detector?</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Dear Masa,</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">May I summarise your requirements:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">1) You mention that you want to simulate a CsI detector, but with 100 % detection efficiency and no interaction within the detector. </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">2) You would like to distinguish between scattered and primary rays.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">3) A monochromatic pencil beam enters a phantom.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">My suggestion:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">I would suggest using a phase space actor (see the <a href="https://urldefense.com/v3/__https:/opengate.readthedocs.io/en/latest/tools_to_interact_with_the_simulation_actors.html*phase-space-actor__;Iw!!PAKc-5URQlI!_P9nlwtwj9dIeV2hHQtSbBZiOOlf2u0klOOSbhmmNrMhNxMxAJN4SgVVz_zaiEj0SQYvfHgXq2pNEPKPSyXWmZGQZIKttg$" target="_blank">documentation here</a>), which registers each particle's energy, position, velocity etc. crossing its surface. Since you do not want to simulate interaction in your CsI detector material, there is no need to use it in the first place.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Since you are using a pencil beam, all primary photons will go straight through your phantom, intersecting your detector at, for example, point (0,0). All scattered radiation will intersect your detector away from point (0,0). Hence, you can filter out the scatter and primary rays purely based on where they end up on your detector.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">To set up your detector, use e.g. a box volume with the desired size, fill it with vacuum, and attach a phase space actor to it. </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">If you need more help, please let us know.</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Best regards,</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">David </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">On 30 Aug2022, at 00:46, mas <<a href="mailto:fight1_fight2@yahoo.co.jp" target="_blank">fight1_fight2@yahoo.co.jp</a>> wrote:</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><pre>Hi GATE users.
I am masa@japan and new to Gate.
I am currently working on a simple simulation.
I am trying to find the point spread function of the scattered rays detected by a CsI detector by injecting a pencil beam of monochromatic X-rays into an acrylic phantom.
Assuming a detector detection efficiency of 100%, I want to output the spread of scattered radiation when it enters the detector.
No interaction occurs with the detector. I also want to output scattered rays and primary rays separately.
How should I set up the detector in such a case?
Should I use Fluence Actor for detection?
Or should I use a sensitive detector?
I would appreciate it if you could help me.
Thank you.</pre><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">_______________________________________________</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)">Gate-users mailing list</blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><a href="mailto:Gate-users@lists.opengatecollaboration.org" target="_blank">Gate-users@lists.opengatecollaboration.org</a></blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><a href="https://urldefense.com/v3/__http:/lists.opengatecollaboration.org/mailman/listinfo/gate-users__;!!PAKc-5URQlI!5R6DdcwuD-nXX0bmvN3RckxZ2HEAgen9ExhbGuDcz_52hS9V1Rohx8vBP7HBR0msh9Bx0lNmj5dJ866ftlukHHjC8jk0_A$" target="_blank">https://urldefense.com/v3/__http://lists.opengatecollaboration.org/mailman/listinfo/gate-users__;!!PAKc-5URQlI!5R6DdcwuD-nXX0bmvN3RckxZ2HEAgen9ExhbGuDcz_52hS9V1Rohx8vBP7HBR0msh9Bx0lNmj5dJ866ftlukHHjC8jk0_A$</a> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"> </blockquote><blockquote style="border:0;padding-left:6px;margin-left:10px;border-left:4px solid rgb(204, 204, 204)"><br></blockquote>