From 6cc4b47709a951c2708565e009f61199813d60b2 Mon Sep 17 00:00:00 2001
From: Karthik Chandrashekara <karthik@physi.uni-heidelberg.de>
Date: Tue, 17 Jun 2025 13:53:41 +0200
Subject: [PATCH] Added manual method to isolate resonances

---
 Estimations/LinearizeScatteringLengthScan.m | 57 +++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/Estimations/LinearizeScatteringLengthScan.m b/Estimations/LinearizeScatteringLengthScan.m
index 271d2e5..38df7a6 100644
--- a/Estimations/LinearizeScatteringLengthScan.m
+++ b/Estimations/LinearizeScatteringLengthScan.m
@@ -65,6 +65,63 @@ ylim([0 150])
 set(gca, 'FontSize', 14)
 grid on;
 
+%% Isolate from spectrum manually
+
+% Get the full spectrum
+[B, a_s] = getFullFeschbachSpectrum(1, 2); % Using new FR params and middle a_bkg
+
+% Define the plotting range
+x_limits = [1.15, 2.7];
+y_limits = [0, 150];
+
+% Find indices within our x-range
+mask = (B >= x_limits(1)) & (B <= x_limits(2));
+B_plot = B(mask);
+a_s_plot = a_s(mask);
+
+% Identify resonances to mask (looking at the spectrum, we'll mask around 2.174G and 2.336G)
+resonances_to_mask = [2.174, 2.336];
+mask_width = 0.1; % Width to mask around each resonance (in G)
+
+% Create a mask for the regions to keep (1 = keep, 0 = mask)
+keep_mask = true(size(B_plot));
+for res = resonances_to_mask
+    keep_mask = keep_mask & (B_plot < (res - mask_width) | B_plot > (res + mask_width));
+end
+
+% Create masked version
+B_masked = B_plot(keep_mask);
+a_s_masked = a_s_plot(keep_mask);
+
+% Interpolate over the masked regions
+a_s_interp = interp1(B_masked, a_s_masked, B_plot, 'pchip');
+
+% Plotting
+figure(3);
+hold on;
+
+% Plot the original spectrum
+plot(B_plot, a_s_plot, 'b-', 'DisplayName', 'Original spectrum');
+
+% Plot the masked regions in red
+for res = resonances_to_mask
+    mask_region = (B_plot >= (res - mask_width)) & (B_plot <= (res + mask_width));
+    plot(B_plot(mask_region), a_s_plot(mask_region), 'r-', 'LineWidth', 2, 'DisplayName', 'Unwanted Resonance');
+end
+
+% Plot the interpolated curve
+plot(B_plot, a_s_interp, 'g--', 'LineWidth', 1.5, 'DisplayName', 'Interpolated');
+
+% Formatting
+xlim(x_limits);
+ylim(y_limits);
+xlabel('Magnetic Field (G)');
+ylabel('Scattering Length (a_0)');
+title('Dy-164 Feshbach Spectrum with Masked Resonances');
+legend('Location', 'best');
+grid on;
+hold off;
+
 %% Helper functions
 function [t, B_ramp, a_check] = generateSmoothBRamp(FR_choice, ABKG_choice, a_start, a_end, selectedResRange, T, Nt, opts)
     % Time array